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-   -   For MOTORHEADS. CA motor build question (https://www.corvetteforum.com/forums/c3-tech-performance/3508991-for-motorheads-ca-motor-build-question.html)

rayluka 07-30-2014 10:35 PM

For MOTORHEADS. CA motor build question
 
Well as we all know the smog nazi's are alive and well in Southern CA. So I have a thought. My car is a 1976 with 49 federal smog regulations. It has a cat ,egr but no air pump. This is my question. Do you think this combo would be smogable.

L-48 motor
Crane Cams 113801 w/carb E.O
Duration Advertised 278° Intake/290° Exhaust
Duration @ .050" Lift 222° Intake/234° Exhaust

Pro comp heads
Aluminum-Cylinder-Heads-190cc runners -64cc-2.02-1.94

New Low restriction cat
Eagle 383 stroker kit

I would like to think based on the fact that stroking wont effect smog, cam has a carb eo, and heads are slightly better (lighter) than factory that this may pass smog.
Would it add enough horses to be worth it?

Comments?:crazy:

Shark Racer 07-30-2014 10:50 PM

Overlap is 0 deg, should be OK.

Pro comp heads are junk. That said... the pics I can find of them looks like they don't have exhaust crossover ports which are required for functioning EGR.

You wouldn't be able to pass a *stringent* smog check with them, but may get by. Depends on how you do on NOx emissions. I'd just get heads with exhaust crossovers.

Personally, I'd go AFRs instead of pro comps. You'll be limited to an intake that will cull power over 5k.

I'd also go roller cam.

I just built a 451hp/485tq (flywheel) smog legal engine. It's fun so far. Haven't had a smog test but the cam is milder than the one you picked, roller though.

rayluka 07-30-2014 11:00 PM

Well Im just trying to get about 300 and pass smog. What would go best with 383 and keep it legal.

76CSRvette 07-30-2014 11:04 PM

the truth I have run cars on smog machine that were modified and passed all hc/co/co2/nox numbers but failed visual. Your car should be able to pass smog if you adjust everything right and and put it back to performance tune after. It depends on the tech checking your car and with the star program now everyone is scared thinking everyones a nark. I had a buddy take a failed car 3 times to same shop first didn't even check timing but passed everything on checklist but failed for running rich and mil light turned on due to faulty wire the second tech checked everything and failed everything so it all come down to really where you take it. The third I just told him what to fix and change and voila pass. they failed my car 10 years ago for having a cai and another shop I took it too just did it and done.

76CSRvette 07-30-2014 11:05 PM

LS1 engine swap bar approved just a suggestion. just make sure intake is has EO carb has eo headers have eo. make sure you have egr and thermo switches and flaps and if its a non California you don't need the AIR pump.

Shark Racer 07-31-2014 12:43 AM


Originally Posted by rayluka (Post 1587483763)
Well Im just trying to get about 300 and pass smog. What would go best with 383 and keep it legal.

Depends on budget; Edelbrock Trick Flow and AFR all make legal heads.

I'd go TFS or AFR myself. I went AFR195 on me. AFR195 if you're doing a 383, AFR180 if you're doing a 350.

You can probably hit the 300 hp number or pretty close w/ a modern cam, up the CR to 9, 9.5:1 and do full headers/exhaust. Heads worth 75-100 hp though, not to mention the weight, cooling and improvement to detonation sensitivity.

Hedman sells legal long tube headers.

My 451 / 484 was with a lightly modified QJet (air bleeds, jetting).

http://elucidus.smugmug.com/photos/i...ZDh4stf-X2.jpg

rayluka 07-31-2014 12:46 AM

If I could get 75 or 100 just with heads and exhaust, that'll work.

rayluka 07-31-2014 12:54 AM

as far as an LS swap, chevy has an erod LS3 smog compliant kit now.

dugsgms74 07-31-2014 01:14 AM

Im a smog tech in cali, heres what youre gonna have to deal with. 1. Visual: the engine is going to have to have all the smog equipment it had on it when built meaning that whatever it equipment it says it has on the emission sticker under the hood or in the motor manual(smog reference book) had better be on the car. 2. Tailpipe test: california has determined what the tailpipe emmisions should be and it cant exceed that. The way the tailpipe emissions are measured differs depending on what zip code your vehicle is registered in, it may be a rolling test at 15 and 25 mph on a dyno or a static test at idle and 2500 rpm.

If youd like to post a pic of the emissions sticker Ill let you know what you need or I can look in up in the motor manual. As far as the cam goes, you cant see it so as long as its mild enough to not pour out HCs youll be fine. Anything else(intake/carb/headers) had better have a CARB E.O.#. Heads..if youre worried about them just paint em engine color and noone will be the wiser.

rayluka 07-31-2014 02:23 AM

Its a 49 federal. Will get pics posted tomorrow. Catalytic converter egr no pump.

Shark Racer 07-31-2014 02:31 AM


Originally Posted by rayluka (Post 1587484509)
Its a 49 federal. Will get pics posted tomorrow. Catalytic converter egr no pump.

Yup, no air pump is nice. :)

FWIW, the AFR heads are EO'd. So even if you did get caught, they're legal.

If you have AC and alternator, the heads are pretty much invisible.

You can't hide not having an exhaust crossover though, a good mech will actuate the EGR diaphragm and if the motor doesn't stumble you'll fail the visual.

rayluka 07-31-2014 02:40 AM

With all that said, How would this combination do? both have eo's

http://www.jegs.com/i/Crane-Cams/271/113801/10002/-1

http://www.airflowresearch.com/index...7ihkrr0hikkue2

Shark Racer 07-31-2014 03:05 AM


Originally Posted by rayluka (Post 1587484535)

I think it would pass but probably a little too aggressive on the cam. The intakes that are available for passing smog legally will cut that cam off. I'd go w/ something with 5-10* less duration on either side.

The closest one I can see by Crane is the Energizer 272 H10 (100052). I ran that one in my old engine iteration, with an auto, a bad tune and old style AFR 195s it made 243 rwhp / 280 rwtq. This was running a real low static CR too. With the alums you can probably go 9.5-10.0 with this cam.

If you're running a 383, go up to the AFR 195s. If you can eke out a few more dollars in your build, switch to a roller cam, aside from the added costs there really aren't any drawbacks.

With that cam and those heads you'd hit your goal though, esp if you keep the CR up. I'd imagine at least 350 hp, maybe 375.


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