And it begins.... 4.2L
#166
#167
Race Director
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seems the E39 M5 is a gateway drug to a GT3, I've now known at least 6-7 GT3 owners that had M5's...
Quick update, Bosch Motorsports 5bar FPR will be here Tuesday/Wednesday and the tuning cable is here already. Should have things tuned up a bit better by the end of next week...
Quick update, Bosch Motorsports 5bar FPR will be here Tuesday/Wednesday and the tuning cable is here already. Should have things tuned up a bit better by the end of next week...
#168
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Do you have any Pix of FPR and part nr
I've tried with 5 bars but it gave a rise of pressure from 3 bar to 5 bar but it does not give so much more fuel after that injecktor will be sluggish for the higher pressure. results more hp on between lo to mid registry but it does not get enough fuel on top.
Regards
Robin
I've tried with 5 bars but it gave a rise of pressure from 3 bar to 5 bar but it does not give so much more fuel after that injecktor will be sluggish for the higher pressure. results more hp on between lo to mid registry but it does not get enough fuel on top.
Regards
Robin
0 280 B02 722-02. As soon as I'm near my car (could be a bit yet) I'll get a picture of it for you.
When I do the math, looking at BFSC of 0.5 (pretty normal for NA cars), Fuel pressure of 73.5psi (5bar) our stock injectors are good for just shy of 600 crank HP at 85% injector duty. (600 crank HP is a dream, if we get to 500whp on our dyno that reads stock 3.6's at 360, I'll do back flips!)
I know real life doesn't always follow the approximations and rules of thumb, but, to your point, as long as the injector doesn't get lazy with the fuel pressure being so high, we should be OK...
I did some digging and the injectors in 997 GT3/RS are Bosch Part 0280158128, 443cc, twin spray 27degree, extended spray end,49mm Oring to Oring, 90mm spray deviation from connector
Looks like a direct higher flowing replacement is 0280158123, 613cc, twin spray, 25 degree, extended spray end, 49mm Oring to Oring 90mm spray deviation from connector. Found some on ebay, but I never trust ebay as fuel injectors are constantly being copied in china...
Out of curiosity what injectors (part number) did you go with?
Last edited by Jamie_GT3; 02-27-2014 at 12:22 AM.
#169
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Just as a FYI, the 997.2 Cups run with 5 bars pressure, returnless system (FPR inside the fuel pump, unless fitted with a fuel cell, then it uses the same FPR as mentioned above). The injectors have R numbers, which means it not the same as the roadcar.
Don't know if this info helps you out with anything, but just to let you know.
Don't know if this info helps you out with anything, but just to let you know.
#171
Rennlist Member
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I think most people on here like the idea of a big bore metzger in the back of their GT3. For most of those that step up to the plate and do it, the engine will come from one of the vendors that have a plug and play engine package available. You've chosen a brave road, can't wait to hear how good she is when you get it all dialed in. Great thread!
Last edited by The Mick; 04-05-2014 at 10:43 PM.
#173
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Breaking in the engine and working on tuning. I had a few tuners lined up and a stand alone, all of posed troublesome. So, I called a friend of mine that's a factory consultant and race engineer to lend a hand with the factory engine mapping. I bought all the tools to do it myself and with his help will be now tuning it on my own...
I'm kind of a DIY guy at heart. The goal at the start was to put together a complete package for others to be able to duplicate at some point. Without having to send the car somewhere. We're getting there slowly, but there are a lot of "moving parts" to get nailed down. Some bumps in the road when you're doing it by yourself. I called Alex at Sharkwerks the other day just to commiserate that it always takes 5 times longer than you thought it would when you do it yourself. He had some good advice to not rush it as I'll have the car forever at this point...
Most important part is to work with people you trust and everyone involved, sans some tuners that shall remain nameless, have been top notch!
CF body panels are just about done, supposed to ship this week (doing a full wide body front end in Carbon, RSR wing etc...). JRZ pro's with an Umbrella Design front lift will be ready in a few weeks and all my tools for tuning this thing will be here next week. In the mean time we drive it on the base tune (which isn't great), to continue getting some miles on the engine and go from there.
I'll do a big write up on it once the engine is tuned with some final numbers. May end up in a magazine if the timing works out...
Yes yes, Mezger...
I think most people on here like the idea of a big bore metzger in the back of their GT3. For most of those that step up to the plate and do it, the engine will come from one of the vendors that have a plug and play engine package available. You've chosen a brave road, can't wait to hear how good she is when you get it all dialed in. Great thread!
Most important part is to work with people you trust and everyone involved, sans some tuners that shall remain nameless, have been top notch!
CF body panels are just about done, supposed to ship this week (doing a full wide body front end in Carbon, RSR wing etc...). JRZ pro's with an Umbrella Design front lift will be ready in a few weeks and all my tools for tuning this thing will be here next week. In the mean time we drive it on the base tune (which isn't great), to continue getting some miles on the engine and go from there.
I'll do a big write up on it once the engine is tuned with some final numbers. May end up in a magazine if the timing works out...
Yes yes, Mezger...
#174
Drifting
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Location: Belmont Shore in Long Beach CA
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Carbon Fiber... Should have called up Wicked MotorSports. Would have done you a 12 inch wider rear end to make it that mans car it really should be.
Now that is a knee slapper
Now that is a knee slapper
#175
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Long Overdue Update:
Was tuning the car and breaking in the engine. Kept having a light throttle cruise lean condition. Added an absurd amount of fuel and got the lean condition gone, then the rpm's would hang at 3000-3500. After some consternation and swearing, figured out that the CF plenum PJS and I had made was cracked 6" at the seam behind the Throttle body... Explains the lean conditions under vacuum and the fact that the rpms would hang as more air was getting passed the throttle than we wanted or calculated...
So, I ordered a factory 4.0RS plenum (they're available now, let me know if anyone wants one...). Charles removed the CF boat anchor from the top of the engine and put the 4.0RS plenum on. Also while he had it we installed the Umbrella Designs Front Lift Kit and JRZ Pro RS coilovers, RSS LCA's, GMG Sways, etc...
Finally had ordered a full Grand AM front end, decklid and wing from RPW (hood, bumper, fenders, undertray, RSR decklid, Wing, etc...) at the end of last year. Many have heard that I had to get my credit card company involved when it all still wasn't delivered come February/March. Contacted the mfg and finally got parts in May.
We got started on the install of the parts and they were not "plug and play" as they were sold to me. Mfg told us to cook them to loosen them up and try again we did this a few times and it helped but they still weren't factory fit as promised... So I contacted him again and he sent all new fenders to try. These were better and now we're finally getting closer to getting the car into paint.
![](http://i62.tinypic.com/2na1lie.jpg)
![](http://i58.tinypic.com/2qm3x95.jpg)
![](http://i61.tinypic.com/9vdv7b.jpg)
Our headers and exhaust are next to finish up. Headers and fixtures for the headers are done, we're working on the muffler now. Design is done, parts secured, just need to build the first few.
Then the car gets corner balanced, aligned and back to me to start over tuning the engine now that it doesn't have a massive vacuum leak!
So many lessons in this. The biggest ones is work with vendors that will deliver parts on time and are of high quality. The plenum leaking cost me about 8 weeks trying to tune it, then figuring out what was wrong, then ordering the parts etc... The body work same deal. Had the parts all shipped last year when they were ordered, car would have been in paint/body over the winter when I didn't need it.
It's getting done and I'm happy that I'm working with the shops I am.
Big thanks to Charles at Gerber Motorsports
and to Hai, Zac and Jeff at Haury's Collision
Was tuning the car and breaking in the engine. Kept having a light throttle cruise lean condition. Added an absurd amount of fuel and got the lean condition gone, then the rpm's would hang at 3000-3500. After some consternation and swearing, figured out that the CF plenum PJS and I had made was cracked 6" at the seam behind the Throttle body... Explains the lean conditions under vacuum and the fact that the rpms would hang as more air was getting passed the throttle than we wanted or calculated...
So, I ordered a factory 4.0RS plenum (they're available now, let me know if anyone wants one...). Charles removed the CF boat anchor from the top of the engine and put the 4.0RS plenum on. Also while he had it we installed the Umbrella Designs Front Lift Kit and JRZ Pro RS coilovers, RSS LCA's, GMG Sways, etc...
Finally had ordered a full Grand AM front end, decklid and wing from RPW (hood, bumper, fenders, undertray, RSR decklid, Wing, etc...) at the end of last year. Many have heard that I had to get my credit card company involved when it all still wasn't delivered come February/March. Contacted the mfg and finally got parts in May.
We got started on the install of the parts and they were not "plug and play" as they were sold to me. Mfg told us to cook them to loosen them up and try again we did this a few times and it helped but they still weren't factory fit as promised... So I contacted him again and he sent all new fenders to try. These were better and now we're finally getting closer to getting the car into paint.
![](http://i62.tinypic.com/2na1lie.jpg)
![](http://i58.tinypic.com/2qm3x95.jpg)
![](http://i61.tinypic.com/9vdv7b.jpg)
Our headers and exhaust are next to finish up. Headers and fixtures for the headers are done, we're working on the muffler now. Design is done, parts secured, just need to build the first few.
Then the car gets corner balanced, aligned and back to me to start over tuning the engine now that it doesn't have a massive vacuum leak!
So many lessons in this. The biggest ones is work with vendors that will deliver parts on time and are of high quality. The plenum leaking cost me about 8 weeks trying to tune it, then figuring out what was wrong, then ordering the parts etc... The body work same deal. Had the parts all shipped last year when they were ordered, car would have been in paint/body over the winter when I didn't need it.
It's getting done and I'm happy that I'm working with the shops I am.
Big thanks to Charles at Gerber Motorsports
and to Hai, Zac and Jeff at Haury's Collision
#178
Rennlist Member
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Very cool! Can't wait to see this beast when it's done! Coming together nicely!
#180
Rennlist Member
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Jamie this looks freaking EPIC! Glad to see you're making all this progress. What front wheels are you gonna fit under those fenders? Looks like you'll beat me to fitting 275s there...