if you look at the effective compression ratios the Ruf system has a slightly lower effective compression.

using 1999's equation:
((boost psi / 14.7) + 1) x motor compression = effective compression

EVO effective compression = 15.91

Ruf effective compression = 15.64

it's only slightly lower.


EDIT: of course, there's more to it than just compression.

 

just picking your brain here.... how does lowering the compression add to longevity if you go ahead and nearly double the psi of a comparable kit, forcing it to produce just as much, if not more power on still stock internals?

 

Power is not just a result of the effective compression ratio. Many cars with a higher ratio produce less power. Look at some of the turbos.

 

with the effective compression rations only being slightly different (with the nod to the Ruf) and everything else being equal, does this mean both kits should produce similar (give or take 10HP or so) power?

 

of couse. i was grossly generalizing.

yes an engine with even higher compression does not equal more power, especially with poor mapping.

ya, look at some of the turbos. they can keep boosting and boosting but fuel delivery, ecu mapping, may not be able to cope.

 

check my math but i think the EVO came out slightly higher.

i suppose with programming, intake temps, exhaust and the same supercharger being the same then there should be similar HP numbers.

with different programming and a different supercharger, who knows. WE won't know until Ruf Auto center shows us those plots .

 

I saw the dyno for you car... Yummy! Damn it's fast and not even boosting all that much either Did you see it yet?

 

Guys to just be sure here and to compare apples and apples I'm going to throw out some info here before we go comparing the EVO 3.4L or 3.6L kit to the RuF 3.8L kit, which isn't really fair How's about comparing the 3.8L EVO kit to the RuF kit... If it's "just north" of 400RWHP let's just say the last dyno I saw for the 3.8L car was 448rwhp Now _that_ is quite a bit different!

I would really love to see/check out one of the RuF kit. I'm sure it's an awesome set up. We've only worked on 3 RuF vin cars before and those were all Turbos but we had a lot of fun doing so....

Karlooz, we're doing another 3.4L NON-Egas C2 with the blower in 10 days time.... Can't wait. Those take to the kit so well. I really hate E-Gas

 

isn't the kit they're talking about here a 3.6 liter 997?

 

you were right. i looked at it wrong.

if the HP is approx the same and the power is applied in a similar fashion, what advantage has the RUF kit gained by lowering the compression with more boost? i still don't really understand that.

i know we're still speculating since RUF won't post the numbers.

 

aw damn, no replacement for displacement .

 

don't think the Ruf SC was on a 997S. thought it was a installed on a plain jane 997

448RWHP for the 3.8L EVO kit is INSANE... that's ~527HP!


sweet! another 3.4L non-egas car. egas sucks that bad huh? gotta start thinking how to put a 3.8L bottom end onto my motor/SC . doesn't help that i have an early '99

 

Ah ok.. well then the 3.6L car just ran an 12.01 @121mph and _if_ I remember right on the 997 3.6L car the dyno was 424rwhp? I'll have to check. In that case I stand SAE corrected:P

I honestly am not a fan of Egas. When I push the pedal I want it to darn well be instant intead of being ECU-aided.... 3.8L bottom end? Oh man you guys are crazier than me...

 

I talked to Mike @ Evo and he said something like 440-460.. wasn't sure if he meant at the crank or wheels. I guess the awe tuning headers and cats helped increase power another 40hp. UNBELIEVABLE!!... can't wait to get her back this week!!!

 

Isn't the supercharged car supposed to put down 450 through the stock exhaust system? In which case, with all the awe parts you should be close to the 500 wheel range?