Req. for comments & questions on my turbo upgrade plan

[Pete_89T2]

Hi guys, this is a follow up to my other post, reference:

http://www.rotarycarclub.com/rotary_...ad.php?t=13083

The skinny is if I decide to purchase a BNR stage 1 upgraded turbo (vs. the stock rebuild) as discussed in the ref. thread, I need to address fuel & fuel/spark management. After a little research here & elsewhere, I've drafted a plan that should support running the upgraded turbo safely and meet my goals. What I'm looking for is your critical review & comments to the plan - pros/cons, etc. I'll also pose a few associated questions along the way that I need answers to prior to executing this plan. This will be a lengthy post, but hopefully will generate information useful to anyone starting out on the FC mod/tuning adventure.

My goals: I'll be more than satisfied if my car even comes close to producing the 300~320 rwhp BNR claims their stage 1 turbo upgrade is capable of. My philosophy is in line with "resto-mod" thinking. Meaning when replacing worn out parts, if you can improve upon stock performance & reliability without compromising the car’s original looks, its character or baseline reliability, then go for it! Reliability is orders of magnitude more important to me than the end HP #'s I achieve. Also, since I’m too lazy to be swapping out emissions components every time the state of MD orders me off to the sniff tester, I will retain the factory emissions components needed to pass the sniff test. Regarding schedule, I MUST have this done and fully tuned before I hit the road for DGRR-11 (28 Apr 11). My gut tells me finding a competent tuner to optimize my tune on a dyno within that short schedule is going to be my greatest obstacle!

Baseline car & current mod list: Car as it sits is a nearly 100% stock ’89 turbo, faithfully restored to “like new” condition. For those of you who attended DGRR ’10, it’s the black-on-black T2 that took home 1st place in show for 2nd gens. Engine was rebuilt about 50K miles & 12 years ago, all stock internals, no porting was done to it. ECU is stock N370, with no mods, but I did install a new Mazda engine wiring harness back in 2008. Currently the stock 550cc injectors are in all 4 holes, which are periodically sent out for refurb & flow testing once every other year. Fuel pump is stock, but I did the FP rewire job some 10 years ago to ensure the FP gets the voltage & current it needs. I’ll need to check my handy work to verify if it's still up to snuff. Exhaust system is a Bonez DP out the turbo (2.5" diameter pipe), going into the stock mid-pipe & main cat, then into a Borla dual cat-back exhaust. Intake is all stock, other than a K&N panel filter installed in the stock box. Other than removal of the pre-cat, all emissions equipment is installed, works and is functional; car easily passes MD sniff test. Other mods relevant to this discussion include a Koyo radiator upgrade which will soon go in (part ordered), and WRT lubrication, I did the e-shaft thermo pellet mod.

Reiterating from the referenced post, the BNR Stage 1 turbo upgrade I’m considering is basically a rebuild of all my stock S5 turbo wear parts, to include balancing. BNR replaces the stock compressor wheel with a T04b V-trim wheel, running inside the stock compressor housing which is machined to fit the new wheel. The waste gate is ported, and the turbine wheel gets some clipping to reduce back pressure. The waste gate is preset to open at 7~8 lbs. They claim this turbo is good for 300~320 rwhp with the right setup.

Planned Upgrades to support the BNR Stage 1 turbo:
Fuel Injectors: Replace all four FIs with 720cc injectors. From what I’ve read so far, these would provide more than enough fuel capacity to support my goals, and putting them in all 4 holes provides the tuner a bit more wiggle room to optimize drivability around the primary/secondary transition point, and throughout the power curve. Questions: (1) Is this true, or for my modest goals would my money be better spent elsewhere by running my stock 550’s in the primaries and just upgrade the secondary’s to 720cc? (2) Where can I source a set of 720cc injectors that are drop in replacements (mechanically and electrically) to the stock 550cc high impedance FIs currently in there? I really don’t want to mess with the stock fuel rails; but can handle the electrical mods to change FI harness connectors if needed.

Fuel Pump: Assuming that I verify I have good voltage at my rewired stock FP, will the stock FC pump be sufficient for my modest HP goals? If not, what replacement FP do you guys recommend and why?

Fuel/spark control: I’m thinking the most expedient and cost effective path for me is to send my stock N370 ECU out to DTI for the RTEK 2.x upgrade. Details of what the RTEK can do may be found here:

http://www.pocketlogger.com/index.ph...age=2&ecu=S5T2

From what I’ve read, it appears the RTEK can provide enough tuning flexibility to support my modest HP targets, and it seems to mesh well with my resto-mod philosophy (i.e., no major hacking/wiring harness work, low risk to stock functionality and drivability). But I’m not 100% convinced yet – answers to the following questions might get me there: (1) Have any of you successfully used an RTEK to wring about 300 HP out of your turbo setups? If so, please share the particulars. (2) I have zero experience tuning ECUs, so out of the box, how easy or hard will it be for me to tune my RTEK modified ECU for the first time at least well enough for me to safely drive the car to a reputable tuner for optimizing on a dyno? This drive is likely to be a 3+ hour road trip, one way, assuming I can get Dave at KD Rotary to do this for me. (3) If Dave can’t do it for me, can anyone recommend a reputable tuner with RTEK & rotary experience within a reasonable drive from the northeast corner of MD?

Thanks!
Pete

[Pete_89T2]

Hi guys, this is a follow up to my other post, reference:

http://www.rotarycarclub.com/rotary_...ad.php?t=13083

The skinny is if I decide to purchase a BNR stage 1 upgraded turbo (vs. the stock rebuild) as discussed in the ref. thread, I need to address fuel & fuel/spark management. After a little research here & elsewhere, I've drafted a plan that should support running the upgraded turbo safely and meet my goals. What I'm looking for is your critical review & comments to the plan - pros/cons, etc. I'll also pose a few associated questions along the way that I need answers to prior to executing this plan. This will be a lengthy post, but hopefully will generate information useful to anyone starting out on the FC mod/tuning adventure.

My goals: I'll be more than satisfied if my car even comes close to producing the 300~320 rwhp BNR claims their stage 1 turbo upgrade is capable of. My philosophy is in line with "resto-mod" thinking. Meaning when replacing worn out parts, if you can improve upon stock performance & reliability without compromising the car’s original looks, its character or baseline reliability, then go for it! Reliability is orders of magnitude more important to me than the end HP #'s I achieve. Also, since I’m too lazy to be swapping out emissions components every time the state of MD orders me off to the sniff tester, I will retain the factory emissions components needed to pass the sniff test. Regarding schedule, I MUST have this done and fully tuned before I hit the road for DGRR-11 (28 Apr 11). My gut tells me finding a competent tuner to optimize my tune on a dyno within that short schedule is going to be my greatest obstacle!

Baseline car & current mod list: Car as it sits is a nearly 100% stock ’89 turbo, faithfully restored to “like new” condition. For those of you who attended DGRR ’10, it’s the black-on-black T2 that took home 1st place in show for 2nd gens. Engine was rebuilt about 50K miles & 12 years ago, all stock internals, no porting was done to it. ECU is stock N370, with no mods, but I did install a new Mazda engine wiring harness back in 2008. Currently the stock 550cc injectors are in all 4 holes, which are periodically sent out for refurb & flow testing once every other year. Fuel pump is stock, but I did the FP rewire job some 10 years ago to ensure the FP gets the voltage & current it needs. I’ll need to check my handy work to verify if it's still up to snuff. Exhaust system is a Bonez DP out the turbo (2.5" diameter pipe), going into the stock mid-pipe & main cat, then into a Borla dual cat-back exhaust. Intake is all stock, other than a K&N panel filter installed in the stock box. Other than removal of the pre-cat, all emissions equipment is installed, works and is functional; car easily passes MD sniff test. Other mods relevant to this discussion include a Koyo radiator upgrade which will soon go in (part ordered), and WRT lubrication, I did the e-shaft thermo pellet mod.

Reiterating from the referenced post, the BNR Stage 1 turbo upgrade I’m considering is basically a rebuild of all my stock S5 turbo wear parts, to include balancing. BNR replaces the stock compressor wheel with a T04b V-trim wheel, running inside the stock compressor housing which is machined to fit the new wheel. The waste gate is ported, and the turbine wheel gets some clipping to reduce back pressure. The waste gate is preset to open at 7~8 lbs. They claim this turbo is good for 300~320 rwhp with the right setup.

Planned Upgrades to support the BNR Stage 1 turbo:
Fuel Injectors: Replace all four FIs with 720cc injectors. From what I’ve read so far, these would provide more than enough fuel capacity to support my goals, and putting them in all 4 holes provides the tuner a bit more wiggle room to optimize drivability around the primary/secondary transition point, and throughout the power curve. Questions: (1) Is this true, or for my modest goals would my money be better spent elsewhere by running my stock 550’s in the primaries and just upgrade the secondary’s to 720cc? (2) Where can I source a set of 720cc injectors that are drop in replacements (mechanically and electrically) to the stock 550cc high impedance FIs currently in there? I really don’t want to mess with the stock fuel rails; but can handle the electrical mods to change FI harness connectors if needed.

Fuel Pump: Assuming that I verify I have good voltage at my rewired stock FP, will the stock FC pump be sufficient for my modest HP goals? If not, what replacement FP do you guys recommend and why?

Fuel/spark control: I’m thinking the most expedient and cost effective path for me is to send my stock N370 ECU out to DTI for the RTEK 2.x upgrade. Details of what the RTEK can do may be found here:

http://www.pocketlogger.com/index.ph...age=2&ecu=S5T2

From what I’ve read, it appears the RTEK can provide enough tuning flexibility to support my modest HP targets, and it seems to mesh well with my resto-mod philosophy (i.e., no major hacking/wiring harness work, low risk to stock functionality and drivability). But I’m not 100% convinced yet – answers to the following questions might get me there: (1) Have any of you successfully used an RTEK to wring about 300 HP out of your turbo setups? If so, please share the particulars. (2) I have zero experience tuning ECUs, so out of the box, how easy or hard will it be for me to tune my RTEK modified ECU for the first time at least well enough for me to safely drive the car to a reputable tuner for optimizing on a dyno? This drive is likely to be a 3+ hour road trip, one way, assuming I can get Dave at KD Rotary to do this for me. (3) If Dave can’t do it for me, can anyone recommend a reputable tuner with RTEK & rotary experience within a reasonable drive from the northeast corner of MD?

Thanks!
Pete