My Twin Turbo Build is Under Way
#141
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If we can "borrow" some wheels for the back of my car that will hold on the dyno, I fully expect to break the 600 hp mark on 93 octane. Now that the weather is cooler, maybe we can even get there without temp/humidity correction.
With meth injection, I hope to be able to break well into the 700 hp range. We have plenty of untapped boost left, so I'm optimistic that we can get it done.
Last edited by ttg35fort; 11-10-2008 at 01:05 PM.
#144
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FYI, Marty has been absolutely GREEAAAT to work with!!!!!!!! I couldn't count how many times I have called him over the past few months, but he never seemed bothered and has always been extremely friendly and helpful!!! Again, I REALLY APPRECIATE YOU GUYS COMING THROUGH FOR ME!!!!! Absolutely top notch customer service.
I know how hard this Cosworth plenum was to get. I feel like a kid at Christmas getting his favorite present that he has been waiting months to get.
![thumbup](https://my350z.com/forum/images/smilies/biggthumpup.gif)
![Smilie](https://my350z.com/forum/images/smilies/smile.gif)
#146
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Yes it is polished. The spacer (custom spacer from Injected Performance) is to make sure that the plenum clears the CJ Motorsports fuel rails. It is my understanding that without the spacer, you are limited to using the Cosworth fuel rails. By the time I decided to go with the Cosworth Plenum, I already had the CJ Motorsports fuel return system on order. Had I decided to go with the Cosworh Intake Plenum from the beginning, I probably would have went with the Costworth fuel rails and used a different fuel return system. Nonetheless, the spacer should suitably address the issue.
Also, I would expect that the extra length that the spacer provides to the intake runners will shift my peak torque slightly lower in the rpm band, which for me I see as a benefit. I'm not sure how much it will do so, but after it is on and we get the car back on the dyno, I'll try to post a comparison between the new dyno chart and my previous one. That also will enable us to see the performance differences between the Cosworth Plenum and the Stock Plenum with the 5/16" Motordyne spacer, at least up to the point where we had to stop the last dyno test due to the wheel spin on the dyno. I think that the Cosworth Plenum really comes alive at high boost in the higher rpms, so even that comparison will be somewhat limited since my original dyno chart stops at 6200 rpm and was performed with only 14 psi of boost.
FYI, Coach K, you were right about your suggestion a few months ago about changing to a different exhaust system!
You also may have been right about the fuel injectors. I ran into idling problems in the beginning. We weren't sure if it was due to the RC Engineering saturated fuel injectors or the stock ECU, but we did the shotgun approach and addressed both. We replaced the fuel injectors with HKS 1000cc low impedance (peak and hold) injectors, had Sam re-flash the ECU and bumped the idle to 1000 rpm. That worked. Since we did the shotgun approach, we aren't sure which change made the most difference, but now it purrs like a kitten. Again, thanks for the advice. When I upped my hp goal to over 600 hp, Nate called me to tell me that the APS 2.5" exhaust no longer would be adequate. Rather than digging into a ton of more research, I thought about what you had said and immediately told him to make the change. Again, thank you!
Originally I was concerned about the Evo TT exhaust being too loud, but its not too bad. I still like the sound of the APS 2.5" better, but I think the extra noise is worth the performance that I am now seeing. Also, running the wastegate dumps back into the exhuast really helps in keeping the noise down, and I don't think this created much of a hinderence to the performance. Since I am bringing the meth system on line, maybe with the meth we will be able to let the Greddy 18Gs completely open up in the high boost setting and keep the wastegates closed? That would be cool. However it pans out, I'll post the results.
Also, now is a good time to thank everybody in this forum. Other than the disputes about shop A being great and shop B sucking, this forum has been extremely beneficial. I have learned a he** of a lot about high performance VQ motors here, and much of the advice given herein has been very beneficial to me in guiding my build selections. Even though people oftentimes disagree, the debates sometimes help to distinguish fact from fiction.
In my opinion, though, it would be even more beneficial if the posts about problems with the various shops were moved to their own sub-forum. That way, if people want to post and/or read opinions about the various shops, both good and bad, that information will still be here, but it won't clog up the other sub-forums, which makes it that much more difficult to find useful technical information.
*************Perhaps the Moderators can consider starting a new sub-forum for shop experiences and move corresponding threads to that sub-forum.*******************
Also, I would expect that the extra length that the spacer provides to the intake runners will shift my peak torque slightly lower in the rpm band, which for me I see as a benefit. I'm not sure how much it will do so, but after it is on and we get the car back on the dyno, I'll try to post a comparison between the new dyno chart and my previous one. That also will enable us to see the performance differences between the Cosworth Plenum and the Stock Plenum with the 5/16" Motordyne spacer, at least up to the point where we had to stop the last dyno test due to the wheel spin on the dyno. I think that the Cosworth Plenum really comes alive at high boost in the higher rpms, so even that comparison will be somewhat limited since my original dyno chart stops at 6200 rpm and was performed with only 14 psi of boost.
FYI, Coach K, you were right about your suggestion a few months ago about changing to a different exhaust system!
![Smilie](https://my350z.com/forum/images/smilies/smile.gif)
Originally I was concerned about the Evo TT exhaust being too loud, but its not too bad. I still like the sound of the APS 2.5" better, but I think the extra noise is worth the performance that I am now seeing. Also, running the wastegate dumps back into the exhuast really helps in keeping the noise down, and I don't think this created much of a hinderence to the performance. Since I am bringing the meth system on line, maybe with the meth we will be able to let the Greddy 18Gs completely open up in the high boost setting and keep the wastegates closed? That would be cool. However it pans out, I'll post the results.
Also, now is a good time to thank everybody in this forum. Other than the disputes about shop A being great and shop B sucking, this forum has been extremely beneficial. I have learned a he** of a lot about high performance VQ motors here, and much of the advice given herein has been very beneficial to me in guiding my build selections. Even though people oftentimes disagree, the debates sometimes help to distinguish fact from fiction.
In my opinion, though, it would be even more beneficial if the posts about problems with the various shops were moved to their own sub-forum. That way, if people want to post and/or read opinions about the various shops, both good and bad, that information will still be here, but it won't clog up the other sub-forums, which makes it that much more difficult to find useful technical information.
*************Perhaps the Moderators can consider starting a new sub-forum for shop experiences and move corresponding threads to that sub-forum.*******************
Last edited by ttg35fort; 11-11-2008 at 03:33 PM.
#147
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There have been a number of changes to my build since I started this thread, and I can no longer edit the first page. Below is my build list as it currently stands. The engine and electronic systems should be completed this week, and my new rear bumper should be going on within the next week or so. The final piece of the puzzle will be the Recaro Seats, which are on order, but will take a while since I am having them custom made with leather to match my factory interior.
*******I DO NOT WANT TO GET INTO A DISCUSSION HERE ABOUT SHOP A SUCKS, SHOP B IS THE GREATEST, ETC. PLEASE POST ANY SUCH COMMENTS IN ANOTHER THREAD *************
VQ35DE Short Block - Built by Import Parts Pro
Eagle/SCAT H-Beam Rods
ARP Rod Bolts
Wiseco 8.8:1 Pistons with Ceramic/Moly Coating
Balanced/Blue Printed Rotating Assy
ARP Main Studs
Modifications performed by Japtrix
ARP L19 Head Studs
Heads Match Ported/Polished
Ferrea Valves
JWT C2 Cams
JWT Springs
HKS Headgaskets
HKS 1000 cc Low Impedance Fuel Injectors (Custom machined by Forged Performance)
HKS Twin Power DLI II Ignition System
Cosworth Intake Plenum
Injected Performance Spacer for Cosworth Plenum
CJ Motorsports Stage 2 Fuel System
SP Racing Tripple Fuel Pump Hanger (2 active Walbros, 1 manually activated Walbro as a spare)
Greddy TD05H-18G Twin Turbo System
Greddy Intercooler
Custom MAF Sensor/Housing Elimination
Tial 38mm W/Gs
SGP External W/G relocation - dumps routed back into the Exhaust System
Tial BOV
54mm Koyo Radiator
Nismo Low Temp Thermostat
Pathfinder Rear Cooling Mod
2 Custom 12,000 BTU Oil Coolers
Rev-Up Oil Pump
Greddy Oil Pan
JWT Oil Pan Spacer
Nismo Rear Diff Cover/Cooler
HKS F-Con V Pro
HKS Navigator
HKS A/F Knock Amplifier - Two O2 sensors
HKS EVC Boost Controller
HKS Turbo Timer Type-1
Coolingmist Meth/Water Pump
Coolingmist 1.5 Gal. Trunk Mount Tank
Coolingmist Smart Injection Controller
Coolingmist Vari Cool Controller
2 x Coolingmist Super High Speed Valves (S-HSVs)
2 x 10 GPH Meth/Water Injectors
Coolingmist Solenoid (to bring the Injectors on-line at different boost levels)
Mike Norris Motorsports PCV Catch Can
Greddy Evo TT Exaust
Custom 3" Test Pipes
Driveshaft Shop Level 2 Axles
Carbonetics Carbon Tripple Disk Clutch
Techna SS Clutch Line
Wilwood Brakes
Tein Flex Coilovers
Tein EFDC System
Stillen Sway Bars
SPC Rear Camber Arms
SPC Front Control Arms
GT Spec Front Strut Tower Brace
GT Spec Rear Strut Tower Brace (On order)
GT Spec Rear Tie Brace
GT Spec Front Lower Tie Brace
GT Spec 4 Point Mid Chassis Reinforcement Brace
GT Spec Rear Lateral Arm Brace
Seibon Carbon Fiber Hood
Kuruma Z Front Bumper
SurfaceModZ CS-Style Rear Bumper
Greddy Side Skirts
APR GTC-300 Carbon Fiber Wing
Mercury Silver Volk GT-S Wheels 19x9.5F, 19x10.5R (30 offset front and rear)
Toyo R888 Tires 305/30/19 - Rear
Michelin Pilot Sport Cup Tires 265/30/19 - Front
Tuning by Japtrix/Horsepower Logic
*******I DO NOT WANT TO GET INTO A DISCUSSION HERE ABOUT SHOP A SUCKS, SHOP B IS THE GREATEST, ETC. PLEASE POST ANY SUCH COMMENTS IN ANOTHER THREAD *************
VQ35DE Short Block - Built by Import Parts Pro
Eagle/SCAT H-Beam Rods
ARP Rod Bolts
Wiseco 8.8:1 Pistons with Ceramic/Moly Coating
Balanced/Blue Printed Rotating Assy
ARP Main Studs
Modifications performed by Japtrix
ARP L19 Head Studs
Heads Match Ported/Polished
Ferrea Valves
JWT C2 Cams
JWT Springs
HKS Headgaskets
HKS 1000 cc Low Impedance Fuel Injectors (Custom machined by Forged Performance)
HKS Twin Power DLI II Ignition System
Cosworth Intake Plenum
Injected Performance Spacer for Cosworth Plenum
CJ Motorsports Stage 2 Fuel System
SP Racing Tripple Fuel Pump Hanger (2 active Walbros, 1 manually activated Walbro as a spare)
Greddy TD05H-18G Twin Turbo System
Greddy Intercooler
Custom MAF Sensor/Housing Elimination
Tial 38mm W/Gs
SGP External W/G relocation - dumps routed back into the Exhaust System
Tial BOV
54mm Koyo Radiator
Nismo Low Temp Thermostat
Pathfinder Rear Cooling Mod
2 Custom 12,000 BTU Oil Coolers
Rev-Up Oil Pump
Greddy Oil Pan
JWT Oil Pan Spacer
Nismo Rear Diff Cover/Cooler
HKS F-Con V Pro
HKS Navigator
HKS A/F Knock Amplifier - Two O2 sensors
HKS EVC Boost Controller
HKS Turbo Timer Type-1
Coolingmist Meth/Water Pump
Coolingmist 1.5 Gal. Trunk Mount Tank
Coolingmist Smart Injection Controller
Coolingmist Vari Cool Controller
2 x Coolingmist Super High Speed Valves (S-HSVs)
2 x 10 GPH Meth/Water Injectors
Coolingmist Solenoid (to bring the Injectors on-line at different boost levels)
Mike Norris Motorsports PCV Catch Can
Greddy Evo TT Exaust
Custom 3" Test Pipes
Driveshaft Shop Level 2 Axles
Carbonetics Carbon Tripple Disk Clutch
Techna SS Clutch Line
Wilwood Brakes
Tein Flex Coilovers
Tein EFDC System
Stillen Sway Bars
SPC Rear Camber Arms
SPC Front Control Arms
GT Spec Front Strut Tower Brace
GT Spec Rear Strut Tower Brace (On order)
GT Spec Rear Tie Brace
GT Spec Front Lower Tie Brace
GT Spec 4 Point Mid Chassis Reinforcement Brace
GT Spec Rear Lateral Arm Brace
Seibon Carbon Fiber Hood
Kuruma Z Front Bumper
SurfaceModZ CS-Style Rear Bumper
Greddy Side Skirts
APR GTC-300 Carbon Fiber Wing
Mercury Silver Volk GT-S Wheels 19x9.5F, 19x10.5R (30 offset front and rear)
Toyo R888 Tires 305/30/19 - Rear
Michelin Pilot Sport Cup Tires 265/30/19 - Front
Tuning by Japtrix/Horsepower Logic
Last edited by ttg35fort; 02-15-2009 at 10:34 AM.
#154
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captj, my favorite misinformed person on the forums. I have never said a bad word about japtrix. I have sent a few people back to receive refunds for the "tune" they received from jack. I have never seen anything bad that japtrix has done at all. As long a roger is tuning then the people have nothing to worry about. The cars that jack "tuned" were set up as naturally aspirated cars and I can't believe they even ran at all. Gus is a cool guy and I have talked to roger and have no issues other than same state rivalry.
Just in time for Christmas... I'm glad when I asked specifically for roger to tune my car - the other roger ASSURED me that jack was MORE than qualified.
#156
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Yeah, I wish you would have had time to see me JT.. My motor finally gave out from running on this shitty Jack "tune" today... Now I'm forced to spend thousands of dollars I wasn't quite ready to spend...
Just in time for Christmas... I'm glad when I asked specifically for roger to tune my car - the other roger ASSURED me that jack was MORE than qualified.
Just in time for Christmas... I'm glad when I asked specifically for roger to tune my car - the other roger ASSURED me that jack was MORE than qualified.
#157
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The Cosworth Plenum is now on and we hopefully will have it back on the dyno this weekend. I'm expecting increased torque throughout most of the rpm range but I'm mostly looking forward to seeing the results below 4000 rpm.
On that note, has anybody had any success using nitrous between 2500 and 3500 rpm to get the Greddy's to spool up faster and to provide extra torque until they do spool up? Specifically, I am thinking about adding nitrous to kick in at 2500 rpm, and then shut it off as soon as 8 psi of MAP is achieved. Any thoughts on this?
On that note, has anybody had any success using nitrous between 2500 and 3500 rpm to get the Greddy's to spool up faster and to provide extra torque until they do spool up? Specifically, I am thinking about adding nitrous to kick in at 2500 rpm, and then shut it off as soon as 8 psi of MAP is achieved. Any thoughts on this?
#158
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The Cosworth Plenum is now on and we hopefully will have it back on the dyno this weekend. I'm expecting increased torque throughout most of the rpm range but I'm mostly looking forward to seeing the results below 4000 rpm.
On that note, has anybody had any success using nitrous between 2500 and 3500 rpm to get the Greddy's to spool up faster and to provide extra torque until they do spool up? Specifically, I am thinking about adding nitrous to kick in at 2500 rpm, and then shut it off as soon as 8 psi of MAP is achieved. Any thoughts on this?
On that note, has anybody had any success using nitrous between 2500 and 3500 rpm to get the Greddy's to spool up faster and to provide extra torque until they do spool up? Specifically, I am thinking about adding nitrous to kick in at 2500 rpm, and then shut it off as soon as 8 psi of MAP is achieved. Any thoughts on this?
#159
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that is something the 300ZX guys do since the VG30DETT is very dependent on boost and down low it needs it, I really have not felt that need in the 350Z with Greddy unless I don't downshift, if I am in the right gear the VQ35 breaths very well and those turbos spool up fast, I thought you already had traction issues anyway
I can slip the clutch to get the engine rpms up quickly, but that is how I fried my last clutch. Even Carbonetics recommends in their manual a particular warm up procedure before launching hard, but that is not always convenient.
Thus, what I would like to do is to get more torque in the lower rpms so I don't have to slip the clutch too much to get a relatively quick launch. Also, I'm going to set the boost on the EVC to be speed dependent. For example, I can have it ramp the boost based on speed so that at 4000 rpm in first gear I only have something like 9-10 psi of boost, but by the time I hit 4000 rpm in second gear I am up to 12 psi of boost, and so on.
Last edited by ttg35fort; 11-19-2008 at 01:40 PM.