TitaniumTT's I hope I make it to DGRR '09 Build

[TitaniumTT]

Originally Posted by Turbo II Rotor

How loud are those 044's? I'm gonna have 2 of them in my hatch feeding off a surge tank. Sounds like I might have to make an insulation box around them.

LOUD! They make the Walbro seem silent..... seriously. To bad you already bought two, I would've sold you mine. Wait, two Scott? Seriously? That's a ton of flow man!

[NoDOHC]

The injectors aren't that bad, ~$65 each I think? Although they are getting replaced over the winter I believe. We were touching 89% duty cycle on the 403 run with another pound to add. i may be upgrading the injectors and the ignition over the winter as well. We'll see what happens if we can ever get a clean dyno day out of her

First: What size injectors are you running ?
Second: Where did you steal them?
Third: 89% slightly high, even for peak and hold (are they linear at that Duty cycle)?

I am currently throwing a lot of ideas around so I may not get to the Twin Turbo idea for a while.
Idea #1 Semi-PP (to be daily driven).
Idea #2 Attempt to get 200+ WHp from 6-port
Idea #3 Try for 300 WHp NA out of my 4-port (Street port only)
Idea #4 Install Twin Turbos (or GT37) and try for 432 WHp (2X NA HP) at 14.5 psi boost (even if, by then, it will have been done before).

Hey, if you want to get one of these off my list for me, I would be content with your word on the feasibility of the 200+ WHp 6-port. (You know you always wanted another project).

The Turbo mod can be done (as you have so illustriously proved), so I mostly would just do it because I want a 432 WHP RX7, the Semi-PP is also because I want one, and the 300 WHp NA streetport is because I think I can.

[TitaniumTT]

Originally Posted by WE3RX7

I go away to paradise and have to come back to this crap! J/K man.. I'm totally stoked you nailed that 400whp with room left!

Of course, this means I'll have to make 450whp, but thats ok. I was going to mention to you at some point, maybe get a locking gas cap, lol. Hopefully the lab gets you some news you can use on the clogging!

That's alright, make your 450RWHP, I'll still have 2x your power down low

If I can ever find a lab that will test filters, I'll be all set. Although now I'm starting to think that it wasn't sabotage, but instead the pump starting failing along time ago and the "Clogging" is due in part to the pump sucking down 2x the amount of Amps that it should, running hot, running slow, and puking parts of magnet, armature, etc, out of itself.

Originally Posted by NoDOHC

First: What size injectors are you running ?

750/1000 - original power goal was to be 350-380. We're beyond that so they're a little short on duty right now.

Originally Posted by NoDOHC

Second: Where did you steal them?

Marren Fuel Injection.

Originally Posted by NoDOHC

Third: 89% slightly high, even for peak and hold (are they linear at that Duty cycle)?

No, which is why I want to go a little bigger. I'm shopping around and will probably change out both primary and secondary but stick to 750. I'm looking into some Paul Yaw injectors to swap out over the winter. Also thinking about swapping fuel rails too. We're not entirely sure.

Originally Posted by NoDOHC

I am currently throwing a lot of ideas around so I may not get to the Twin Turbo idea for a while.
Idea #1 Semi-PP (to be daily driven).
Idea #2 Attempt to get 200+ WHp from 6-port
Idea #3 Try for 300 WHp NA out of my 4-port (Street port only)
Idea #4 Install Twin Turbos (or GT37) and try for 432 WHp (2X NA HP) at 14.5 psi boost (even if, by then, it will have been done before).

I like the semi p-port idea. I think 200whp from a 6-port is feasible, I've seen 187rwhp. Although the 13 extra will probably require a MAP based system and a custom intake, but I bet it's doable. 300whp from a 4-port would be sweet though, I bet you'd have to spin the bejeezus out of it, and run a custom mani. I think it's a stretch though. The highest N/A hp I've ever heard of, strait from the mouth of the guy that did it was 380BHP in a P-Port.. 380BHP would equate to ~315 wheel.

In my opinion, in order to get 2x N/A power running just about 2x N/A "boost" you would need a turbo whoes "plugging" effect is equal to the very small amount of power that's missing from the vac @ WOT. It would be interesting to dyno this engine N/A.

Originally Posted by NoDOHC

Hey, if you want to get one of these off my list for me, I would be content with your word on the feasibility of the 200+ WHp 6-port. (You know you always wanted another project).

I think I found one actually - I may be picking up an FD roller in the very near future I think 200 whp in a 6-port is entirely possible.

Originally Posted by NoDOHC

The Turbo mod can be done (as you have so illustriously proved), so I mostly would just do it because I want a 432 WHP RX7, the Semi-PP is also because I want one, and the 300 WHp NA streetport is because I think I can.

Semi P-Ports are cool. I would be much more impressed with a 2 rotor, 300 whp N/A though... that would be badass.

[WE3RX7]

I go away to paradise and have to come back to this crap! J/K man.. I'm totally stoked you nailed that 400whp with room left!

Of course, this means I'll have to make 450whp, but thats ok. I was going to mention to you at some point, maybe get a locking gas cap, lol. Hopefully the lab gets you some news you can use on the clogging!

[NoDOHC]

Originally Posted by TitaniumTT

It would be interesting to dyno this engine N/A.

You can say that again!! I would love to see that (0.91L and 38 BTDC timing FTW)

Originally Posted by TitaniumTT

I think I found one actually - I may be picking up an FD roller in the very near future I think 200 whp in a 6-port is entirely possible.

Do you intend to take the Twin Turbo out and put it in the FD and then build the 6-port for the '88? If so, I would hope that most of the beautiful intercooler work would port over to the FD (although I think you like doing that kind of thing anyway).

Originally Posted by TitaniumTT

Semi P-Ports are cool. I would be much more impressed with a 2 rotor, 300 whp N/A though... that would be badass.

Originally Posted by TitaniumTT

300whp from a 4-port would be sweet though, I bet you'd have to spin the bejeezus out of it, and run a custom mani. I think it's a stretch though. The highest N/A hp I've ever heard of, strait from the mouth of the guy that did it was 380BHP in a P-Port.. 380BHP would equate to ~315 wheel.

I won't know until I see what I get for power from an E8 (Yukon Coil packs) and 9.5:1 rotors. According to my calculations:
Actual Power: 216 WHp @ 7500 rpm and 160 Wlb-ft @ 6100 rpm
Power based on VE with 8.2:1 rotors (if ignition is really an issue and it isn't something else) = 248 WHp @ 8500 rpm and 176 Wlb-ft@7700 rpm
Power based on no VE change going to 9.5:1 rotors (11% increase) = 277 WHp @8500 rpm and 195 Wlb-ft @ 7700 rpm
Power based on lower dynamic head loss from shorter-runner custom intake manifold (Shifting power band 1000 rpm) = 195 Wlb-ft@ 8500 rpm = 315 WHp @ 8500 rpm

Bear in mind that none of these calculations require VE in excess of 108%, nor do they require revving in excess of 9,000 rpm, so they should be completely feasible. Of course, this relies on piston-engine rules of thumb holding true. Namely:
Torque is a direct function of VE
Compression ratio improves performance by about 8% per full number in the 9:1 range
Intake runner loss calculations (relying on relative surface smoothness, number of bends and length) are similar for a rotary.

We will find out in the spring (if I ever get the high compression rotors in the engine and an E8 for in the car).

(I am expecting the streetport to exceed my P-port power, actually) I am going to build the P-port using Renesis housings so that I can locate my exhaust port differently.

[TitaniumTT]

Originally Posted by NoDOHC

You can say that again!! I would love to see that (0.91L and 38 BTDC timing FTW)

HA! That's ballsy for an engine that's so pristine I would have to build an entirely new exhaust system and I seem to be getting overloaded with projects this winter. Altough, I think the RE mani would be the best suited for an N/A - least amount of bends.

Originally Posted by NoDOHC

Do you intend to take the Twin Turbo out and put it in the FD and then build the 6-port for the '88? If so, I would hope that most of the beautiful intercooler work would port over to the FD (although I think you like doing that kind of thing anyway).

The FD will recieve a 13B-RE engine. Whether it is the engine that is in the FC, that will be determinted based on timing. Ideally I'd build an RE with twin GT28's or 32's sporting thier own wastegate and runner. They'd be parellel which is why I'm leaning towards the GT28's. I'd like to see 450 RWHP and slightly quicker spool than I'm getting with the twin's running non-sequential.

I still haven't put a deposit on the FD, although I did just call the owner to let him know that I'm ready to do so.

Originally Posted by NoDOHC

I won't know until I see what I get for power from an E8 (Yukon Coil packs)

What are you running for coils now?
I would REALLY like to see some back to back comparisions between whatever coils you're using now and the Yukon truck coils. I'm actually planning on upgrading to them over the winter. Either those or some Bosch coils that have been dyno proven to give an increase over the renni coils which the guys at MoTeC loved for a long time.

Originally Posted by NoDOHC

and 9.5:1 rotors. According to my calculations:
Actual Power: 216 WHp @ 7500 rpm and 160 Wlb-ft @ 6100 rpm
Power based on VE with 8.2:1 rotors (if ignition is really an issue and it isn't something else) = 248 WHp @ 8500 rpm and 176 Wlb-ft@7700 rpm
Power based on no VE change going to 9.5:1 rotors (11% increase) = 277 WHp @8500 rpm and 195 Wlb-ft @ 7700 rpm
Power based on lower dynamic head loss from shorter-runner custom intake manifold (Shifting power band 1000 rpm) = 195 Wlb-ft@ 8500 rpm = 315 WHp @ 8500 rpm

Bear in mind that none of these calculations require VE in excess of 108%, nor do they require revving in excess of 9,000 rpm, so they should be completely feasible. Of course, this relies on piston-engine rules of thumb holding true. Namely:
Torque is a direct function of VE
Compression ratio improves performance by about 8% per full number in the 9:1 range
Intake runner loss calculations (relying on relative surface smoothness, number of bends and length) are similar for a rotary.

If you're going for some 9.5:1's.... isn't it 9.7:1?.... why not just go for broke and rock some FE 10:1's?

Originally Posted by NoDOHC

We will find out in the spring (if I ever get the high compression rotors in the engine and an E8 for in the car).

(I am expecting the streetport to exceed my P-port power, actually) I am going to build the P-port using Renesis housings so that I can locate my exhaust port differently.

Why would you expect a street port to exceed the P-Port? The P-Port will be peakier no doubt, but it can swallow a ton more air. I would think that the P-Port would overtake the street port after a certain RPM.

[TitaniumTT]

So I thought I would give a little update.

The Supra TT pump, while it is dimensionally the same as the Cosmo pump, it is infact ever so slightly different in it's output. It produces roughly 10% more flow than the Cosmo pump at the same voltages and pressures. I am currently looking for the cheapeast place to buy them so if anyone can get them for <$200, let me know. That's the cheapest I've been able to find.

This pump, while it's basically the same as the Cosmo pump and I don't like replacing broken parts with the same parts, will give me the flow that I need if I decide to swap turbo's and go for a 450whp turbo setup. I doubt the I will though. THe car is retardedly fast as it is. I was at a autox event over the weekend on race tires and couldn't keep traction at all. Traction Control is something that I need to do over the winter. I need to work an input to turn it off though

[EJayCe996]

Originally Posted by TitaniumTT

So I thought I would give a little update.

The Supra TT pump, while it is dimensionally the same as the Cosmo pump, it is infact ever so slightly different in it's output. It produces roughly 10% more flow than the Cosmo pump at the same voltages and pressures. I am currently looking for the cheapeast place to buy them so if anyone can get them for <$200, let me know. That's the cheapest I've been able to find.

This pump, while it's basically the same as the Cosmo pump and I don't like replacing broken parts with the same parts, will give me the flow that I need if I decide to swap turbo's and go for a 450whp turbo setup. I doubt the I will though. THe car is retardedly fast as it is. I was at a autox event over the weekend on race tires and couldn't keep traction at all. Traction Control is something that I need to do over the winter. I need to work an input to turn it off though

Can't help you with that one

[NoDOHC]

Originally Posted by TitaniumTT

HA! That's ballsy for an engine that's so pristine I would have to build an entirely new exhaust system and I seem to be getting overloaded with projects this winter. Altough, I think the RE mani would be the best suited for an N/A - least amount of bends.

If you polished the outside radius of each bend and equalized your cross-sectional area throughout the runner and matched that to the port. You should see significant improvements on my 216 WHp. I would expect your engine to make about 240 WHp as it sits, (given the previous assumptions based on piston engine knowledge) With the following additional assumptions:
Intake port timing has been changed to close a little later than stock.
Intake manifold has been port matched, but not blueprinted.
Non-polished rotors do not significantly impede flow past TDC cusp in the rotor housing.

If your manifold were Blueprinted (constant cross-sectional area through entire intake runner) I think you could look 260 WHp in the face.
If you didn't change stock port timing, I think you could get 285 WHp.

Believe it or not, (it seems impossible to convince turbo guys of this) 0.91L will not hurt your engine NA. 1.1L will not hurt your engine NA. You will not burn a hole in a rotor (your rotors are oil-cooled) and detonation is not a problem when you are naturally aspirated. Ignition timing is not a problem either, run whatever give peak power (34 BTDC may be better for you with 9.0:1 CR and un-polished rotors). If it makes you feel better, run 0.86L (this will give almost identical power to 0.91, these are the edges of the peak power range).

Originally Posted by TitaniumTT

The FD will recieve a 13B-RE engine. Whether it is the engine that is in the FC, that will be determinted based on timing. Ideally I'd build an RE with twin GT28's or 32's sporting thier own wastegate and runner. They'd be parellel which is why I'm leaning towards the GT28's. I'd like to see 450 RWHP and slightly quicker spool than I'm getting with the twin's running non-sequential.

Why RE and not REW? I think that the RE has bigger intake ports (could be good, if runners will match) and earlier exhaust port opening (not necessarily good for EGT). What other advantages does it have?

Originally Posted by TitaniumTT

What are you running for coils now?
I would REALLY like to see some back to back comparisions between whatever coils you're using now and the Yukon truck coils. I'm actually planning on upgrading to them over the winter. Either those or some Bosch coils that have been dyno proven to give an increase over the renni coils which the guys at MoTeC loved for a long time.

Bone Stock 200,000+ miles coils that came on the car.

Originally Posted by TitaniumTT

If you're going for some 9.5:1's.... isn't it 9.7:1?.... why not just go for broke and rock some FE 10:1's?

The rotors are 9.5:1 because they have been polished to 2000 grit and lightened to < 4kg. (CR empirically determined with sealed ports).

I have a very limited budget for this car, most of my parts were either obtained out of the scrap hopper at work, given to me by friends or custom fabricated by your's truly. I try not to spend much money on this hobby.

Originally Posted by TitaniumTT

Why would you expect a street port to exceed the P-Port? The P-Port will be peakier no doubt, but it can swallow a ton more air. I would think that the P-Port would overtake the street port after a certain RPM.

I don't intend for the P-port to be a crazy runner, I am not building it for such. It will have 9.4:1 normal rotors, minimal overlap (for a PP) and tame port sizing. My goal is not to rev it to 12,000 rpm and make power all the way, but rather to see if I can get it to be mild-mannered and street-drivable while still making 250 WHp. I see it as the poor man's PP.

The only way to make a P-Port swallow more air than a streetport is to make the intake port larger than the combined total of both intake ports on the street port and to make the exhaust backpressure absolutely minimal, while maximizing the intake pressure. High-overlap engines tend to be more finicky and make less average power than equivalently built lower-overlap engines. Building them is not really that easy. (For example, I have a combined cross-sectional area of intake ports/runners of 3.2 in2, this would be a very large P-port, slightly over 2-inch diameter). I am intending more like a 1.7-2.0 in2 port cross-section for the p-port. I want to try for max power on a later p-port, but this one will have stock internals and I will not rev it past 9,000 rpm (eliminating the need for big ports).

Piston engine guys need large overlap times to scavenge the chambers and to get air through their restrictive intake valves and runners. Rotaries don't have any of those problems with > 270 degrees of eccentric shaft rotation per intake stroke from a street port or 320 from a p-port (duration is not that much better on the P-Port)

The VE (empirical, based on fuel and AFR, probably reads 3-5% high due to injector energization delay) on my 4-port breaks 100% @ 4800 rpm, peaks at 108% @ 7700 rpm and drops to 102% @ 9,000 rpm. At tuned resonance, a P-port could achieve ~125% VE (due to overlap), but could not hold that for a broad torque curve. Peaky power bands do no good for performance, area under the Horsepower curve is your friend.

I really should be posting this in the general Rotary tech section, but most of it is already there.

[TitaniumTT]

Originally Posted by NoDOHC

If you polished the outside radius of each bend and equalized your cross-sectional area throughout the runner and matched that to the port. You should see significant improvements on my 216 WHp. I would expect your engine to make about 240 WHp as it sits, (given the previous assumptions based on piston engine knowledge) With the following additional assumptions:
Intake port timing has been changed to close a little later than stock.
Intake manifold has been port matched, but not blueprinted.
Non-polished rotors do not significantly impede flow past TDC cusp in the rotor housing.

If your manifold were Blueprinted (constant cross-sectional area through entire intake runner) I think you could look 260 WHp in the face.
If you didn't change stock port timing, I think you could get 285 WHp.

That's retarded amounts of HP.
Intake timing is slightly later on closing, intake mani port-matched but not blueprinted..... thought about going the extrude hone route but decided to save that expense for two reasons,
1-see if there actually is a difference worth the $600 or more cost
2-didn't want to spend the coin of I didn't need to in order to hit my goal

Originally Posted by NoDOHC

Believe it or not, (it seems impossible to convince turbo guys of this) 0.91L will not hurt your engine NA. 1.1L will not hurt your engine NA. You will not burn a hole in a rotor (your rotors are oil-cooled) and detonation is not a problem when you are naturally aspirated. Ignition timing is not a problem either, run whatever give peak power (34 BTDC may be better for you with 9.0:1 CR and un-polished rotors). If it makes you feel better, run 0.86L (this will give almost identical power to 0.91, these are the edges of the peak power range).

You don't have to convince me, I know for a fact that it won't. It just amazes me the difference any amount of boost makes to these engines. .85-.9 seems to be where the most power can be made though, regardless of turbo or not. There's just an extra safety margin when you tune it to .8. For example, I was looking through the datalogs from this past weekends auto-x, L were around .9 the whole time, when on the highway they were below .8....... tires were constantly breaking loose. 3rd gear pulls will read leaner than 4th gear pulls on the dyno too because everything is slowed down.

Originally Posted by NoDOHC

Why RE and not REW? I think that the RE has bigger intake ports (could be good, if runners will match) and earlier exhaust port opening (not necessarily good for EGT). What other advantages does it have?

RE has bigger runners, less of a complex UIM, and the LIM is MUCH more balanced. The only way I would do an REW would be with the GZ LIM. To fit an RE in an REW all you have to do is get the rear iron drilled and tapped to accept the stock motor mounts. You actually might not even need to do that. You could probably fabricate something off the subframe to use the RE's stock mounts and adapt some FB or FC mounts.

I like to open the exhaust up for an earlier opening but not change the closing at all. That's what I did with this RE engine and it seems to work pretty well. EGT's are just fine with this.

Originally Posted by NoDOHC

Bone Stock 200,000+ miles coils that came on the car.

Nice, I'm wondering how weak the LS1 coils are compared to the LS2 truck coils. Cleaning my fuel up from .75 to .8 nets HUGE gains in power. Much more than you would expect. I'm wondering if there isn't a problem igniting the rich mix and that's were all the stumbling comes from.

Originally Posted by NoDOHC

The rotors are 9.5:1 because they have been polished to 2000 grit and lightened to < 4kg. (CR empirically determined with sealed ports).

Gotcha, interesting that you lost so much CR from such minimal work. Were they balanced as well?

Originally Posted by NoDOHC

I have a very limited budget for this car, most of my parts were either obtained out of the scrap hopper at work, given to me by friends or custom fabricated by your's truly. I try not to spend much money on this hobby.

me too

Originally Posted by NoDOHC

I don't intend for the P-port to be a crazy runner, I am not building it for such. It will have 9.4:1 normal rotors, minimal overlap (for a PP) and tame port sizing. My goal is not to rev it to 12,000 rpm and make power all the way, but rather to see if I can get it to be mild-mannered and street-drivable while still making 250 WHp. I see it as the poor man's PP.

The only way to make a P-Port swallow more air than a streetport is to make the intake port larger than the combined total of both intake ports on the street port and to make the exhaust backpressure absolutely minimal, while maximizing the intake pressure. High-overlap engines tend to be more finicky and make less average power than equivalently built lower-overlap engines. Building them is not really that easy. (For example, I have a combined cross-sectional area of intake ports/runners of 3.2 in2, this would be a very large P-port, slightly over 2-inch diameter). I am intending more like a 1.7-2.0 in2 port cross-section for the p-port. I want to try for max power on a later p-port, but this one will have stock internals and I will not rev it past 9,000 rpm (eliminating the need for big ports).

Piston engine guys need large overlap times to scavenge the chambers and to get air through their restrictive intake valves and runners. Rotaries don't have any of those problems with > 270 degrees of eccentric shaft rotation per intake stroke from a street port or 320 from a p-port (duration is not that much better on the P-Port)

The VE (empirical, based on fuel and AFR, probably reads 3-5% high due to injector energization delay) on my 4-port breaks 100% @ 4800 rpm, peaks at 108% @ 7700 rpm and drops to 102% @ 9,000 rpm. At tuned resonance, a P-port could achieve ~125% VE (due to overlap), but could not hold that for a broad torque curve. Peaky power bands do no good for performance, area under the Horsepower curve is your friend.

I really should be posting this in the general Rotary tech section, but most of it is already there.

Interesting math on the P-port vs street port. As for the VE's, that's a ton of math man!

[WE3RX7]

Oh now you want 450whp, lol. I just plant a little seed and watch it grow

When do you start your winter projects?? More importantly the stopping part of the equation?

[TitaniumTT]

First project shows up tomorrow - and it's a boat Once that's done, time depending, the trailer gets done, then we'll see. I'd like to get my FC stripped and put back together before the end of the year so if something comes up, she's already ready for DGRR. I'm hoping for an FB resto to be here around 1/1 and if it's not, I'll prob get crackin on my FD (assuming I get it) and then back to the stoppage of the FC in early March.

[NoDOHC]

Didn't someone make 217 Dynojet WHp using an RE on the 'evil forum'

I was pretty sure that the RE was the best flowing manifold (when stock). Polishing runners decreases the boundary layer thickness in the runner, which effectively increases the cross-sectional area. I have seen visualizations (dust in air, etc.) with a significant boundary layer of 0.25 inches. This decreases the equivalent diameter to 1/2 inch less.

My stock Primaries were 1.1" minimum effective diameter, based on the surface finish they would have a 0.17 - 0.2 " boundary layer, giving a dynamic effective diameter of around 0.75"

My stock Secondaries were 1.375 minimum effective diameter, giving me about 1.0" dynamic effective diameter. This means that I had a dynamic cross-sectional area of about 1.25 in2

With a 400 grit polished surface, I have a 0.03" Boundary layer (using simplifications of eddy generation) This means that my 1.3" effective diameter Primaries have a 1.24" dynamic effective diameter, while my 1.63" Secondaries have a 1.57" effective diameter. This gives a dynamic cross-sectional area of 3.14 in2. Matching these to 2.95 in2 dynamic cross-sectional area (combined) intake ports (80 grit polished) gives a near-optimal combination (slight increase in velocity after fuel mixing).

Ports that are too big are actually worse for NA power than slightly small ones (loss of velocity will cause poor fuel mixture, causing uneven charge distribution, uneven and incomplete combustion.

Some rough on the inside of each bend is good. (Maximizing turbulence on the inside actually improves air distribution in the runner). My LIM is not balanced, nor are the runner lengths any where near optimal (3300 rpm Helmholtz, 18,000 Sonic). Which is why I want to build a 9" runner intake for my engine.

HA! That's ballsy for an engine that's so pristine I would have to build an entirely new exhaust system and I seem to be getting overloaded with projects this winter. Altough, I think the RE mani would be the best suited for an N/A - least amount of bends.

Just stick a stock exhaust manifold and 2-feet of slightly bent pipe (to minimize clean air reversion to the wideband) on your engine and run it, that will give you as much power as a full exhaust with headers (Dave might not appreciate the sound). I really want to see what you make, so that I can compare my calculations with some real numbers.

DISCLAIMER:

Actual numbers for my engine have been obtained using careful measurement of the cross-sectional area of the intake runners on my manifold. All other numbers are a result of my interpretations of complex formulas, personal experience with 4 and 2 stroke piston engines, advice/suggestions from competant friends and research into this field (SAE papers, books, etc.).

I am not sure that any of the knowledge applies to rotary engines, which is why I have undergone this process, to determine if it does.
So far these NA piston engine rules of thumb have been validated:
Peak power at 0.9L = 13.3:1
Peak torque at 38 degrees BTDC
Torque is function of VE (up to 6,000 rpm, anyway).

NA piston engine Rules of thumb yet to be validated:
If Torque is not linear function of VE, ignition timing or intensity is suspect
Around 9.0:1 CR, torque increases about 8% per full CR increase (8.5:1 - 9.5:1).

My personal theory about Port overlap being unnecessary on a rotary engine as 270 degrees of duration is possible without it is yet to be validated.

SECOND DISCLAIMER:
Please don't misunderstand my continued abuse on late intake port closing. For a turbo application, it is ideal, as it allows additional boost while maintaining equivalent peak compression pressures.

I don't offer much advise to turbo engine builders, as I have very little experience with turbo cars, Snowmobiles, Small block and big block Chevy, Small block Ford, Small block Chrysler, Type 1 - 4 Volkswagen beetle, etc. is where I have experience.

[TitaniumTT]

Originally Posted by EJayCe996

Can't help you with that one

I have 2 numbers to call tomorrow

Originally Posted by NoDOHC

Didn't someone make 217 Dynojet WHp using an RE on the 'evil forum'

I was pretty sure that the RE was the best flowing manifold (when stock). Polishing runners decreases the boundary layer thickness in the runner, which effectively increases the cross-sectional area. I have seen visualizations (dust in air, etc.) with a significant boundary layer of 0.25 inches. This decreases the equivalent diameter to 1/2 inch less.

My stock Primaries were 1.1" minimum effective diameter, based on the surface finish they would have a 0.17 - 0.2 " boundary layer, giving a dynamic effective diameter of around 0.75"

My stock Secondaries were 1.375 minimum effective diameter, giving me about 1.0" dynamic effective diameter. This means that I had a dynamic cross-sectional area of about 1.25 in2

With a 400 grit polished surface, I have a 0.03" Boundary layer (using simplifications of eddy generation) This means that my 1.3" effective diameter Primaries have a 1.24" dynamic effective diameter, while my 1.63" Secondaries have a 1.57" effective diameter. This gives a dynamic cross-sectional area of 3.14 in2. Matching these to 2.95 in2 dynamic cross-sectional area (combined) intake ports (80 grit polished) gives a near-optimal combination (slight increase in velocity after fuel mixing).

Ports that are too big are actually worse for NA power than slightly small ones (loss of velocity will cause poor fuel mixture, causing uneven charge distribution, uneven and incomplete combustion.

Some rough on the inside of each bend is good. (Maximizing turbulence on the inside actually improves air distribution in the runner). My LIM is not balanced, nor are the runner lengths any where near optimal (3300 rpm Helmholtz, 18,000 Sonic). Which is why I want to build a 9" runner intake for my engine.

I should buy a second RE UIM and LIM (I actually had a set, but sold it Oh well, I would want to buy an entire engine anyway to get a few extra parts as well) and send it to you to play with, then send it to be coated, then bolt it on this engine and see what the difference is. I'd be interested.

Originally Posted by EJayCe996

Just stick a stock exhaust manifold and 2-feet of slightly bent pipe (to minimize clean air reversion to the wideband) on your engine and run it, that will give you as much power as a full exhaust with headers (Dave might not appreciate the sound). I really want to see what you make, so that I can compare my calculations with some real numbers.

It's not a matter of noise on the dyno, it's a matter of driving 5 hours with it and spending a few hours taking the turbo's off and then re-installing them. I'd like to try it as well as I'm always interested in actual numbers as opposed to internet dyno's. Sadly though, I don't have the time for it right now. Next year maybe. Right now I'm scratching my head trying to find time to build a legal exhaust system so I can pass emmisions and keep the car "legal" by 11/22.... I hate CT. After this it's one more time.... ugh. Lets hope they don't pop an engine this time.

Originally Posted by EJayCe996

DISCLAIMER:

Actual numbers for my engine have been obtained using careful measurement of the cross-sectional area of the intake runners on my manifold. All other numbers are a result of my interpretations of complex formulas, personal experience with 4 and 2 stroke piston engines, advice/suggestions from competant friends and research into this field (SAE papers, books, etc.).

I am not sure that any of the knowledge applies to rotary engines, which is why I have undergone this process, to determine if it does.
So far these NA piston engine rules of thumb have been validated:
Peak power at 0.9L = 13.3:1
Peak torque at 38 degrees BTDC
Torque is function of VE (up to 6,000 rpm, anyway).

NA piston engine Rules of thumb yet to be validated:
If Torque is not linear function of VE, ignition timing or intensity is suspect
Around 9.0:1 CR, torque increases about 8% per full CR increase (8.5:1 - 9.5:1).

My personal theory about Port overlap being unnecessary on a rotary engine as 270 degrees of duration is possible without it is yet to be validated.

SECOND DISCLAIMER:
Please don't misunderstand my continued abuse on late intake port closing. For a turbo application, it is ideal, as it allows additional boost while maintaining equivalent peak compression pressures.

I don't offer much advise to turbo engine builders, as I have very little experience with turbo cars, Snowmobiles, Small block and big block Chevy, Small block Ford, Small block Chrysler, Type 1 - 4 Volkswagen beetle, etc. is where I have experience.

The rotary as it applies to port timing, overlap, VE, CR, etc etc etc is a totally different animal. Fuel will make the peak torque regardless of what engine it's it becuase it's still being ignited in the same envirornment. The Ignition timing I would have suspected would hold true as well because it takes the same amount of time (degrees of rotation based on BTDC timing) to ignite to build peak cylinder pressure. Add boost though, and all that goes out the window. I still believe that one of the reasons the rotary is so susceptable to detonation is in the overlap. Not because of a scavenging effect, but becuase hot exhaust gases can very easily make thier way into the intake charge and well, boom

[TitaniumTT]

Update -

Bought a Supra TT pump today and it's slated to arrive on Thursday.

Hopefully the final playdate with Dave is set. Like I said back in June, we're gonna get this thing all set and ready to rock and roll and I'm gonna pull her apart for the winter.

Oh, last update - I've joined the ranks of the legally insane - I bought an FD roller Picking her up sometime around the start of December after I get one boat gone, my boat winterized, and a lean-to built out of shrink wrap to keep her in for the winter. What in the hell am I thinking? Oh wait, I know

So here's a question for the people following this thread.........
I've got a bunch of things that I plan to do over the winter to the FC. The first trip will be to DGRRX. So, do I continue with this thread and re-name it, or do I start a new one titled - I hope I make it to DGRRX beginning when I pull her apart to tackle my ever expanding To-Do list?