450hp+ Smog-legal engine combos
#1
450hp+ Smog-legal engine combos
Lately, I have been getting a lot of inquiries about late-model engine builds. I'm in California, so they HAVE to pass CA State SMOG laws. I wanted to see what are some good combinations that make 450 or more hp, but still pass the strict SMOG tests. Please list your NA, head/cam/compression combos with the hp rating. Thanks for your help.
#2
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My old car with a stock LS6 longblock and a 224 cam passed the sniffer and made 425rwhp when I put the headers back on. Would probably make around 380ish with stock manifolds and cats.
My bets for most of the big power smog legal combos would be getting an LS2/3/7 swapped and BAR'd.
Check out the GMHTP website, they have been working on a smog legal build, with AFR 205's LS6 cam, and some other stuff. It made close to 400 wheel with stock manifolds and cats and all smog equipment. They just started putting an STS kit on there, as that is smog legal. As well as some of the procharger kits are.
My bets for most of the big power smog legal combos would be getting an LS2/3/7 swapped and BAR'd.
Check out the GMHTP website, they have been working on a smog legal build, with AFR 205's LS6 cam, and some other stuff. It made close to 400 wheel with stock manifolds and cats and all smog equipment. They just started putting an STS kit on there, as that is smog legal. As well as some of the procharger kits are.
#3
I was thinking about doing 6.0L, with 243 heads and of course, an aftermarket cam...just not sure about how much camshaft to run, when dealing with the smog laws...sounds as if you have a pretty stout set-up for the street...
I was trying to stay away from the forced inductions for now...most inquires come from people wanting to do heads/cam/intake/throttle-body, etc. stuff.
I was trying to stay away from the forced inductions for now...most inquires come from people wanting to do heads/cam/intake/throttle-body, etc. stuff.
#7
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Not saying it's impossible, But 400 rwhp is a more reasonable expectation. If you're going to pass a strict visual, the cats need to be in their stock location. This limits you to CARB approved shorty headers in California. With some badass heads (91 octane limits you to too much compression/milling), 224ish high lift cam on a 114, a great tune and all the supporting bolt on stuff (EWP, UD pulley, ported TB, cutout, etc.) you might top 400. I think you'll have to spray it to top 450....
Now if your car is fairly lightweight, with good suspension, gears etc. 400ish rwhp is no joke.
Now if your car is fairly lightweight, with good suspension, gears etc. 400ish rwhp is no joke.
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#9
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im interested in this one too. im aiming for 400 myself with N/A and streetable manners. of course, im not limited to cali rules though, but id like to stay as close to legal as possible stilll got my EGR and AIR hooked up to my LT headers lol and got HF cats on my y pipe... mostly for sound purposes... and smell. but 400 range would be nice to get into with heads and cam. jusst dont know which to go with.
#11
I hear you guys. I do appreciate your input. Stock Z06 'Vettes come with 405 hp. I'm thinking that with an after-market cam, re-tune and headers, 450 is way doable. I'm not really fluent in cam choices for these LSx engines, yet. Haven't built too many smog-legal, LSx vehicles either. Not too sure about how aggressive I can get with camshafts.
#15
I have the same question as well... don't have the car running yet, but I have a 224/288 cam 114 LSA +2 (or something like that) w/ heads similar to TSP stage 2.5, stock block, pistons/rods, have to run stock manis and cats, CA legal. Gonna try to have this thing on a dyno by next spring, I'll let you know how it turns out. Shooting for 350-400 whp in 2900# car ('93 Mazda rx-7). Real goal is to run the 1/4 high 11's @ ~115-120 mph.
#16
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I have the same question as well... don't have the car running yet, but I have a 224/288 cam 114 LSA +2 (or something like that) w/ heads similar to TSP stage 2.5, stock block, pistons/rods, have to run stock manis and cats, CA legal. Gonna try to have this thing on a dyno by next spring, I'll let you know how it turns out. Shooting for 350-400 whp in 2900# car ('93 Mazda rx-7). Real goal is to run the 1/4 high 11's @ ~115-120 mph.
a full bolt on car should be around 350 rwhp, cam and bolt ons should be 380-410, and cam and heads should be 410+(usually around 430 depending on cam and head choice.
#17
sounds good guys.i live in montana and do not have no smog problems.i have a stock lq4 out of a 2001 truck.i have long tube headers on it in my 69 camaro but i would like to add some other small things to try to make close to 400 crank hp any help would be great.
#19
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If I remember correctly I've seen people running a 383 stroker with a small (224ish druation) cam with a good tune, but I'm not sure how much HP they were making to the wheels. You would have to run shorty headers and some smog legal heads. You could run a P1 charger with certain mods and still be smog legal. The main thing will be the cam and the bottom end that the tech really won't be able to tell by looking at the engine if it's CARB approved or not.
Matt
CA Licensed Smog Tech
Matt
CA Licensed Smog Tech