Just wondering if anyone knows what kind of RWHP gain i could get going from stock 1.5s to 1.7rr's with my minimal mods below... or maybe i should do a gear first

 

ask yourself this question: do you plan to mod the car farther, such as heads or a cam? if so i would get a gear. if you plan on staying a bolt on car, i would say go for the 1.7RR....because when you select your cam, get one with enough lift for your needs

does having such a big rr (1.7) make the valvetrain unstable?

Jesse

 

Since 1.6rr's put the stock springs darn close to coil bind I'd say you're not going to get away with 1.7rr's w/o replacing springs as well.

 

The only cam i would go with, would be a hotcam.. and a hotcam with 1.7rr's would be a fairly nice setup..

If i go 1.7rr's im definetly replacing almost all of the valvetrain except the lifters (pushrods, springs, retainers, etc)

Now anyways, what kind of gains should i expect?

 

If you want 1.7rr's with the hotcam, you need some srpings other than what come in the hotcam kit. Once again, they are just barely enough for what they were intended for.

 

I wouldnt buy the kit... then i would be stuck with 1.6rr's and chitty springs... i know what im talking about, i just want to know what kind of RWHP gain would i get going from 1.5 to 1.7 on stock cam/heads

 

Well since you usually hear of people gaining 10-15 rwhp from 1.6s...(most say they picked up between .1 and 1 mph to .2 and 2 mph), I dont see why you couldn't pick up 20-25 rwhp by going to 1.7s.

I hope to gain that much when I do mine in a month or two.

 

94GrayV6, whats your current best right now?

 

My best is a 13.47 @102.5 w/ a 2.03 short time. That was before the tranny rebuild, tune-up stuff, Meziere, MAF. I've had some hesitation/knock retard issues with it for a while so I don't have any recent times. Once I get it all sorted out I should be in the 13.2 range I think.

 

I see... I think my 2.73s is what's really killing me

 

All I have is an intake, Cut-out and no cat. I'd look elsewhere for what is slowing you down.

 

Hmm, well I just replaced my opti today... Its been crapping out slowly for awhile and my best (13.72) was on that crappy opti... It would have some bad low rpm misses, maybe that effected my time? Well eventually the misses were all over the rpm range and m #1cylinder wouldnt fire anymore... But wow, it feels great now, like a totally different car opti install wasnt too bad either, probably less than 3 hours

 

Just wait and get a cam with more lift... go with gears first, those 2.73's are not needed in a car trying to go fast. Don't even buy a hotcam kit, get your stuff from combination motorsports. They will make you a nice kit with a 224/230 or a 230/236 with multiple variations of each or whatever other cam you want with all the supporting cast (pushrods, lock retainers, valve springs, rr's etc. etc.)

 

A lot of the power you gain is from fresh springs replacing worn out stockers, there was a big post about this last year.

 

not to sound like an a**....... but does anyone actually have dynos proving 15 RWHP just from adding 1.6rr on a stock head/cam car??? just doesnt seem like it could

after reading all these "1.7rr" threads nobody has yet to come back and PROVE that they actually make a difference. i asked my local shop (only specialize in LT1, LS1, LS6's) about the 1.7rr. they said it would be a minimal gain, nothing you would notice. and when you think about it is going to cost about $300+ just to switch to the 1.7's.

so why do people bash the hotcam that we pay $450 for and picked up almost 90 RWHP between that and headers, and yet all you guys are willing to spend $300+ to get maybe 10hp??

id be glad to eat my words... but somebody show a before/after dyno!!