Daytonars4

Anyone happen to know of detune/tune options that have worked for the 4RS CS? I know for BOP they use restrictor plates. But I’m looking to detune similar to what I did with my CS by just reducing max throttle. I used the Cobb Tuner before but there seems to be some doubt about it being capable for the 4RS. Ideally I want to also drop redline to around 8400. I’m starting to wonder if part of the reason 4RS’s seem to be going through motors is related to them pushing them to higher rpm’s than the Cup’s.

thuggo

Wait what? Thats the first I've heard about 4RS motors not having a reasonable life.

Daytonars4

I think if you talk to some of the pro teams running them it’s fairly common knowledge at this point. I’ve probably see 5x4RS CS’s for sale so far with over 8k miles. 100% of them had a replacement engine. From what I understand that was largely due to tune issues where the PDK was overrevving the engine. So it certainly can’t hurt to back the rpm down a little. Especially since the motor is falling flat after around 8500rpm anyway.

thuggo

Aren't the GT3 Cup engines designed for 9k rpm? If so..I'm not sure bumping them down is really going to fix that problem.

RossP

I thought that bumping down the rev-limit (even 2-300 RPM) on a cup car was a pretty easy way to extend operating life. Would that same logic not apply to the 4RSCS?

thuggo

I'm just thinking if they already bumped them down from the factory 400-500 RPM and they aren't lasting, what is another 200-300 going to do? Sounds like a bigger issue.

YMGT4

I have noticed this as well- 8k mile life out of an engine is not exactly GT4 budget...

Daytonars4

It's 9k redline on the 4RS. That's not bumped down at all. I have also heard that even a 300rpm dropped on the redline for the Cups will increase life by a good margin. So really that's more so the angle I'm focused on. With power dropping around 8500rpm anyway, there's just no reason to not take the life expectancy gain by dropping it. It really shouldn't be much if any loss in pace I would think.

shizzle

I know it's not a real solution, but what about setting the shift lights to change at lower RPM? If won't cut engine power, but could help achieve the same objective.

sonorous

If I were trying to do this, I would start by contacting M Engineering and see if they can make a custom tune to do this. I am not sure if they have the 4RS cracked yet but they are well regarded in this area.

steve0827

This is probably the best suggestion. And then you don't have to deal with any BS if you want to go into a series that requires cars to be strictly by the homologation.

Daytonars4

Dropping revs with the dash is what PMNA suggested. I’ll definitely do that. Dropping revs on the engine alone seems doable based on what tuners have said. But whether they can get the PDK to cooperate while in auto seems to be the big question mark. If I were the only one driving the car I probably wouldn’t be as concerned. But with others involved (Some DE rentals) it’s helpful to have a hard cap. I’m guessing as more of these cars get into amateur hands in the next year it’ll be more of a common thing. Someone always has to be the first!

38D

Yeah getting the PDK to know the new redline would require a PDK retune as well. Maybe just have everyone drive in manual mode, which IMO is better anyways.

cafe_racer

If these things are churning engines it, to me, defeats the purpose of not just getting a cup car. 718 clubsport might indeed be the sweet spot.

thuggo

Yup. If you have to effectively detune the engine to get it to last....that defeats the purpose of the car. You can have a 718 MR and upgrade its aero to match the RS for like 100k less than what they are going for.