Quote:
Originally Posted by FreshFRS
i agree with most of the guys here, i mean my s2k went turbo (built motor but 11.5:1 comp) and i ran 15psi on pump gas through it with no problems and for lots of kms (<75,000) i drove it hard too and in winter. a better example in the Cobalt SS/TC 2.0 Ecotec, DI with 10.5:1 compression guys are running 400+whp out of 24Psi on the stock block with pump gas (94 here in canada), 9:1 is overkill and is going to kill off boost response. unless you want 40+psi with lots of lag anyway i really don't see anything less than 10.5:1 being viable for the street. this is all IMHO anyway.
Power on the s2k was 445whp/305tq @15psi is what we settled on, 18psi needed meth injection to be liveable. though we managed to make a couple runs without meth. This is on Engine without DI or VVT (VTEC kicked in at 4300 and only has 2 profiles) which would increase the boost threshold for sure. @ Jason@DSG
Also food for thought, s2ks that had lowered compression(8.8-9:1) are running 5-7psi more than this car to produce the same power/torque. stock 11.3:1 compression blocks have generated 520+with 93+ meth at 17-18psi, 701/450 at 27psi on 116 and 740/470 on E85 at 30psi. |
And that's without DI too! I see no reason why an FA20 with forged internals at 12.5:1 couldn't hold ~450whp on pump gas easily for a long life.
If you're after a lot more than 200hp/L, then sure you'll want lower compression but if everyone is being honest, how big of a market is that compared to the 350-450whp market in a 2800lb rwd car? Even 400whp is A LOT for these cars to put to the ground, what good would 600whp+ do you beyond bragging rights?