MtBikR

Thanks for responding Devin, I have seen the credit show up. I understand delays in this business, and appreciate your following up on my concerns. I have only talked to one person in FL who claimed to have a failed pulley and your explaination makes sense to me. Steve's is working find and I believe that you guys to produce quality products.

scalbert

Are you talking about with the all the standard SC pulleys from Comptech?? If so that 3.5 PSI with the IMRC connected would be about right. There are multiple pulleys involved here and I wanted to verify which ones you are referring to??

paynnsx

Yes, that is a liquid/air IC. I've run 10.5 psi to date on pump gas with absolutely no knock count at all. The motor will be running this spring with 14-15 psi - I expect 475 whp at least with no problems on pump gas.

scalbert

BTW, what is the CR on that engine?? Do you have any feel for IC efficiency and what do you normally run for WOT A/F ratio?? Thanks...

paynnsx

9.5:1 CR. Not sure on the IC efficiency to be exact, but my IATs under full boost in fourth gear never climb above 125 F on a 90 F day - I have not measured pressure drop either. My air/fuels at WOT are 11.8 - 11.9.

scalbert

I assume that you lowered you CR as I beleive the NSX was above 10:1 from the factory; 10.2:1 or so??

Anyway, cool and thanks for the feedback. I am currently tuning for that same A/F range and it seems to like it. I don't plan on running any more boost over the 8 PSI peak on 93 octane. Surprisingly I am having no knock even without any retard on the timing; the IC must be doing what it was meant to do.

paynnsx

I have a fully built, low comp motor with Darton sleeves.

allmotor_2000

I would expect around 575whp @ 14-15psi on that motor - I owned one for several years.

What kind of power are you extracting at 10.5psi?

paynnsx

I'm just trying to be realistic. I'm making just over 400 whp at 10.5 on pump. I've got a couple friends hovering around the 500 mark with turbo setups at 15 psi on pump gas and no one has (honestly) blown past the 500 mark yet.

allmotor_2000

500whp must feel pretty darn nice on that car! Running 15psi on pump-gas (even if IC'd) is pretty amazing on a stock setup. At this point, what fuel modifications are they using; rising-rate regulators w/stock injectors get quite useless at this point!

Nice car BTW

I am currently working on a turbo-setup on my CL-S; did one a while ago but it wasn't the greatest - power peaked at 5400 RPM (350whp @ 5.5psi). Obviously the turbo was too small considering this motor makes most of its power from 5500RPM to 7200RPM. So, we chose a Garrett GT35R which should be ample. Hoping to hit 400+ whp at around ~7psi. Engine management involves 370cc injectors (with a low-ramp rising-rate FMU) and the Greddy E-Manage. Internals are stock, so probably 8psi is the most I will attempt considering CA's horrid 91-octane.

scalbert

After a week of testing I am going to take another step. This is based on not detecting knock when the fuel was tuned properly and without any retard.

I am going to get another pulley made. The current one works great and was of excellent quality. However, I want to see what the limits are and at what point knock occurs. With the last 3.5 inch pulley supplied, boost now peaks at 8 PSI but averages about 6.5 – 7 PSI. This was up from 5.0 - 5.5 PSI average with the base 3.8 inch pulley. In other words, boost went up about 1.5 PSI by going from the 3.8 inch to the 3.5 I am currently running. Once I tuned the A/F ratio there was no knock at all present. That is a testament to intercooling when running that boost on a 10.5:1 CR engine.

I suspect I can run an average of 8 PSI (with a quick spike to 9 PSI) after tuning the fuel and do this safely. This will require a 3.3 inch pulley from what I can tell.

So I am ordering a 3.3 inch pulley just like the previous 3.5 inch pulley I recently received.

mattg

scalbert for president.

ModAddict