OK, the title for this thread might be slightly misleading, because I haven't installed my HSR yet - but I have a question.

It seems like I've seen more than a couple people state that they've added the HSR to an otherwise mostly-stock L98 car, & it runs great, no issues with idling, driveability, etc. But my understanding is that on our cars, the computer relies at least partially on the EGR system, which the HSR has no provisions for.

So what gives? Why do the cars (apparently) run OK, even without the EGR?

(Yes, that was one of the things that's kept me from installing it yet...)

Thanks guys.

 

I would suggest at a minimum to disable the EGR in the ECM, I know you can have this done when you have a custom chip made or you can DIY. Also I should have some more info next week on my setup.

 

The reason the EGR is not an issue is because there is a temperature sensor at the base of the EGR valve. Once that temperature sensor reaches the proper temp, it tells the computer "Ok I'm warm enough now so you can enable EGR function" If you have the sensor disconnected or if it does not ever reach temperature, the computer will never enable the EGR function and it will not set a code. I did this for years on my 305 with aluminum L98 heads. aluminum vette heads do not have an exhaust crossover, so the intake never warms up and the sensor never reaches proper temp. That is why guys swap to the HSR or swap to non-crossover heads and do not have EGR issues.

 

so i can untie the egr temp sender from my wiper motor?

 

OK, that makes sense, thanks 1meanZ.

So Marc, ya wanna come over sometime soon & help me throw on the heads & HSR? Sounds like it'll run OK on the stock tune...

(On a serious note, I can't wait to see how your car runs - wouldn't surprise me too much if you got low-13s/high-12s even at this altitude!)

 

I'd love to come over and help you install yours if you will loan me your fuel adapter fittings untile mine come in. (check mhtg pm's)

 

no problem, thats what the boards are for.