N/A or Turbo

[Pettersen]

So i have a turbo engine with streetport but i needs a lot of work to get it finished, nothing on the shortblock, just on the attached parts.
Need to fix some oil leaks.
Make a new downpipe and port up the wastegate pipe on the manifold to allow for a bigger wastegate.
Mount the universal Fmic kit i got.
Either mount my Rtek 2.1 and be limited to 0.5Bar boost, since i can't remove the MAF and the Garrett T66 outflows that pretty early according to someone on this forum, or get a Haltech sprint RE and do it proper.
+++
And in order to get the car street legal with the turbo engine i need to get a lot of papers from mazda stating that the car is approved with the amount of HP i have(at very low boost ofcourse ), but getting the papers and dealing with the people that aprove cars is a pita!

I just bought a N/A engine wich is legal to have in the car, wich i will put in and use while i finish the turbo engine and get all the paperwork done.

But it would be so much easyer to just stick with the NA engine. It's harder to spot tuning on the NA than the enourmous T66 turbo, so i wouldn't haveto get it approved. + i could sell my turbo stuff to partly finance rebuilding the T2 4port to a fully buildt NA engine
Two other reasons i want to go the NA route is that less stuff on the engine means less stuff that can fail = less downtime, and i actually like NA more than i do turbo, i can live with less hp than my turbo engine as long as it's not to little.

+ the standard stupid newb question
How much hp can i expect to get out of a 4port 13B, streetport, true dual headers with little restriction in the exhaust, standalone and ITB's? Ballpark number ofcourse.

[Raksj04]

If you want to go N/A why not use a 6 port engine? I am pretty sure the port timing is different on a T2 engine then a N/A engine. I would guess 200whp ish depending on porting and injectors. But I am not 100% sure. Most people use a 4 port engine without a turbo because it was what they had to get the car driviable.

[Pettersen]

Cause i have a 4port engine, and with itb's i won't use the 6 port system anyway. But i have put the T2 engine up for trade with a NA engine on a Norwegian mazda forum, so i'll see if anybody bites :)

If i get another 6 port engine i will just go ahead and bridgeport it.

[infernosg]

What you're describing is exactly what I'm currently building although my engine is a bit of a cluster...

S4 TII irons
S5 N/A rotor housings with turbo exhaust sleeves
S5 N/A rotating assembly

Port is Defined Autoworks "Circuit Port." They're also going to be making an intake manifold for me and I'll be using EFI Hardware's 55 mm IDA-style throttle bodies. I'll also be using Defined Autoworks' header and everything will be tuned with a Haltech Sprint RE. I have no idea what the final power will be, but Defined did 230+ whp with a naturally aspirated 13B-RE with the same port and header combination in a 1st Gen.

N/A is definitely more difficult to make power as it's not as forgiving to setups that aren't optimized. That being said the average person will always make more power with a turbocharged car. I'm relying heavily on Logan's knowledge to optmize my setup.

I'm not sure why you say turbo would be easier to spot considering the N/A setup you've described will also stick out quite a bit.

[Raksj04]

Does a N/A benifit from a higher redline then a turbo engine?

[RETed]

There's no need to raise the redline if the engine doesn't significantly make more power at the higher RPM's.


-Ted

[Pettersen]

I'm not sure why you say turbo would be easier to spot considering the N/A setup you've described will also stick out quite a bit.

I know what you mean, but it would still be NA, people that doesn't know rotarys can't say for shure they didn't come with itb's, but turbo and fmic, you don't need to know rotarys to know they don't belong in NA cars.

[infernosg]

Does a N/A benifit from a higher redline then a turbo engine?
Depends on the port but typically turbocharged cars will make more HP and at lower engine speeds (just look at stock FC HP numbers). With accompanying modifications N/A power is increased through displacement and/or engine speed, which do you think is the easier to go after? That's not saying you can't have a 10,000 RPM turbocharged car but that's a lot of stress (and heat) on the turbo.

[Libor]

Most people use a 4 port engine without a turbo because it was what they had to get the car driviable.No. They use 4 port engine because its superior for power and torque production, no matter what porting is applied to irons...

Does a N/A benifit from a higher redline then a turbo engine?Its quite strange question. Turbo engine is very same as NA engine, it just operates in different absolute pressures. Certainly, once you reach maximum torque you can produce in NA engine, only way to increase power is to carry this torque to higher rpms and high rpms=huge stress and wear on everything. So in case of turbo engine, its always better to turn up the boost then trying to spin it to the moon:rofl:

There's no need to raise the redline if the engine doesn't significantly make more power at the higher RPM's.

-Ted
+1

To the OP, if your system will be really optimized, it could go over 250 HP@crank. That being said, most streetported 13Bs are probably making around 220 HP... It depends on to much things...

[Pettersen]

What would i need to do in order to run RX8 rotors?

[Libor]

What would i need to do in order to run RX8 rotors?

A few things which aren´t worth a hassle given the fact, that RX8 rotors were already proved to be inferior to S5 NA rotors in any measurable aspect, mainly in power pruduction...

You don´t even need high comp rotors, great power can be made on lower CR ratio, you just tune accordingly...

[Pettersen]

Well a few things have been decided.

I'm going semi pp and with 9.7 Rotors, and all the nececary machining and parts to get it able to run high rpm's.