rotrex c38r spec sheet
 

Attachment 131291

whos good at math lol

So I’ve been trying to do the math myself with the info I have from the spec sheet, hoping someone on here can correct me if Iam wrong, I’ve been trying to figure out roughly how much boost the new c38r can produce, I came up with 17.75lbs of boost at sc units max.

Someone correct me if Iam wrong please. Not saying that’s correct but it’s what I came up with.

I did the math as well came out to about 18 lbs with the 85mm pulley ..I was gonna change pulley size back up to bring it down ....however ...I removed the supercharger kit and sold the white nismo and made the turbo car my main project ...as much as I loved the supercharger even with the new c38r the TQ of a turbo is hard to beat

So my math was close, great.

And yes Iam toying with the idea to go turbo but if this c38r puts out some good results I may just upgrade the sc because yes the torque of the turbos can’t be beat but my sc setup has been nothing but great and reliable with zero issues in 3 years, iam gona switch to e85 next season and see what I can get out of my current setup, I’ve realized over the years that the power will be never enough lol

The c38r will be a big improvement ....the things that concerned me with it was ...1) 17-18 lbs would be too much for stock bottom end so you would be increasing pulley size to bring boost down to 14-15 which would contradict the supercharger upgrade by around 50% ...2) you would still lack in TQ for the expense 3k for new supercharger for around 2lb boost ...3) you could modify your supercharger kit over to boosted performance kit very easy ....remove supercharger and put everything back stock .leave motor mount in ...flip the intercooler around to put BOV on driver side ..use intercooler and upper intake pipes ...and everything else from supercharger kit .....buy the Comp turbo...exhaust piping ...lower charge pipes..wastegates ..and retune

Leaving motor mount opens up the area to run the air filter to the front above the sway bar for easier filter change ..right now you have to remove the turbo to change it

Interesting.

I’ve entertained the turbo idea a few times but I think I’ll stick with the sc for now, I have planned to build the motor even before I boosted it, I can do all the work myself which saves lots $$$, and have part supplier nearby here in Canada, might even give the jwt cams a try to, e85 will be a huge difference with the lower combustion temps, reduced detonation etc, my friend converted to e85 on his supra with amazing results, and seb at specialty z recommended it even on my current setup and ecutek will give even better results. I’ll post my e85 experience once converted

Nice ... I just put my meth kit on and will be getting retuned on sept 12 ... hoping for some good numbers

I thought you might be interested

oh nice numbers, how many psi of boost?

I stopped at 14 and didn’t get too aggressive with the tune ..had room for more timing and little more boost but didn’t feel it was worth it right now ..gonna focus on traction issues and look into rear diff upgrade

ya stock bottom end and you are making good torque,dont wana ruin it,are u using ecutek?

traction is a big issue with these cars, re71s in the rear and a camber adjust helped alot on my car, ive been researching diffs also.

I’m using uprev ....and run MSS 305/35/19 and I just got some mickey Thomson ET street ss 305/35/18 for the dragstrip ....I have been looking at quiafe ...wavetrac and os gilcon but not sure which ......and yea the TQ is really good ,I didn’t want over 550 ...buddy of mine dynoed his at 16.5 lbs and made 689/608 on stock bottom end ....he turned it back down to 640/550