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How much 383 stroker engine can I get away with?

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1-ton

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I am planning on building a 383 Small Block for My Crew Cab 4X4. How much engine is your best guess that I can get away with, and still pass the tail pipe sniffer test? I have seen some companies that offer a 383 that is guaranteed to pass smog with only 310 HP, and another that claims to be smog legal, but is not guaranteed to pass smog with 330 HP.
 
I dont think size really matters. Good piston rings, good vacuum hoses, spark plugs, and of course emissions stuff play a big part. Also the cat converter.

How well the engine is put together and how finely tuned your system is are factors for emissions.

edit: Also. Power AND emissions can both be increased by increaseing efficiency. Anyone ever tell you that you cant get mileage and power? They're wrong. Its all about efficiency. Why do you think vortec heads are so popular? They are efficient and combust the mix very well. Thats also why TBI heads were a step up from carb heads. The vortecs can just flow better, and are slightly more efficent. So if you run your engine around a 195 thermostat, a fuel system tuned to your engine, and dont have things that decrease efficiency like bad filters, crummy oil, etc. you will lose power and your motor has to work harder to get done what it needs to.
 
My main concern is how much camshaft and compression can I get away with in a 383, and still pass the tail pipe sniffer test. Can a camshaft with about 260 Degrees (advertised) lift and 9:1 compression pass the tail pipe sniffer test, or will I have to go with a 240 duration, and 8.8:1 compression in order to pass?
 
What are your plans? Roller or flat tappet cam?
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Good Question. I am planning on going with a roller, but I am not too familiar with roller cams. How do they differ in relation to specification comparisons with a hydrualic cams performance?
 
Well, if your block is set up for a roller cam, I have always been a fan of the gmpp 383/350 ramjet cam. It creates flatout crazy torque and it is relatively cheap for a roller cam. Its also a quite mild cam that creates good vaccum and economy. For flat tappet cams, lunati's Voodoo series is comperable to the gmpp cam. The benefits of a roller are numerous. For one, its reduces friction and wear on the valvetrain. Second, it creates better profiles and more area under the curve. One bad thing is the cost of the roller cam, but gmpp's cam is only about 130
 
Thanks for the camshaft recomendation. I did some research on the cam you suggested, and it does seem like a perfect cam for what I want to build.

Specifications: Part #14097395/ Roller Tappet Design. Lift .431” I / .451” E; Duration @ .050, .196° I /.207° E

This same camshaft also comes in the GM Performance HT-383. I am just wondering if an HT-383 would be computer compatable and pass smog.
 
I have never been checked, but was told by my builder that the LT1 cam I am using would pass emmissions testing. 201/208 Duration @ 0.050. This cam was fairly easy to get a chip programed that worked with the comp.
 
I have never been checked, but was told by my builder that the LT1 cam I am using would pass emmissions testing. 201/208 Duration @ 0.050. This cam was fairly easy to get a chip programed that worked with the comp.
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I was looking at that cam too. Summit Racing sells that cam with a complete kit including springs and rockers arms for $530. Summit Racing sells the Ram Jet/HT-383 cam alone for $160.
 
Passing smog

On my 383, I pull the modified chip out and swap the stock one back in a couple of blocks before I get to the testing station :waytogo: I live in Illinois, so we have dyno stations to go through. I tried it once with the modified chip, but didn't pass. My engine builder is D&L Automotive in State College,PA. Dennis Chencharick is the guy to speak with about cam selection.
 
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