mcm95403

As part of my research before buying a C4, I'm looking at an engine build later down the road. Right now I'm thinking a 383 with either a stock LT-4 cam, or possibly the HOT cam if it will pass tailpipe here in California. Anyone have any solid data on this? Also, this would probably be a TPI car as I prefer the styling of the early C4 to the later models - sure do like the LT-4 though.......

Thanks,
Marc

cv67

It will pass no problem. Get a tune and youre set. dont use the stock cam on a 383.

mcm95403

So, you think the stock LT-4 cam is still too mild for a 383 TPI car? I'll be keeping the build mild and will probably also end up using an automatic as my old left knee is bothering me again....

bill mcdonald

I have a 90

With the ZZ9 cam from tpis and my 355 cubes I passed 3-4 times now. I just bolt up stock exhaust (with egr) and put the stock chip in to pass. I have a super ram on mine.

If I was looking for a C4 now, I would be looking for an LT4. Only thing I hate on those cars are the opti sparks. Drove a Grand Sport a lot and I LIKE!

bill mcdonald

okay forget the lt4. I am pretty sure they are all manual trans.

mcm95403

ARGH, yes you're right - the 96 LT-4's are all manual trans only. Guess that means I'm going for an early C4.

cv67

TPI car with an auto Id use a different cam with the 383.
Maybe 219 Lingenfelter at the largest, there are a number of them out there that will work. Keep the intake duration@ /050 arounf 220ish or less and youll be fine. Being as it wont spin up high dont need a large cam just one that enhances torque. The 383 will swallow the cam up and make it act smaller anyway. Do whatever you can to upgrade the TPI. USed aftermarket runners/base, port them whatever you can its a choke point. Theres always the super ram too if you can find one. FIRST makes a real sweet TPI system but dont think they are 50 state legal.

tpi421Vette listed on from Crower the other day that looked real interesting maybe hell pipe in

mcm95403

Just looking at the specs, the stock LT-4 cam is 203/210 @ .050" and .476/.480 lift with the 1.6 rockers. The HOT cam is 218/228 and either .492 or .525 depending on the rockers. I figures it should still be fairly mild with the extra stroke of the 383, but maybe it would be a little much.

I'll definitely work the TPI system. I love the SuperRam, but may have to work with a stock TPI setup for smog reasons. I'll dig into that more when the time comes.

Anyone know if the SuperRam has EGR? I haven't seen any provision for it in the pics I've seen and without it, it's a no-go in CA.

cv67

SR is 50 state legal. With a TPI no need for a cam with much overlap like the hotcam. Sure you can use it but theres better choices for TPI/auto car.

What heads are you using?

Kool88vette

Superam has a carb number and is legal in all 50 states. It is set up for an egr.

mike100

my friend also has the zz9 in a 91 tpi and it passes, but 91 is allowed higher levels than 92 -95, but still, a warm cam will pass in a 90's car for CA...it's more about visual inspection in this state than tailpipe emissions.

with a different than stock engine size, I'd be worriedabout a higher compression level spewing more NOx levels if the EGR doesn't quell it.

CAJUN C4

I think the GM ZZ4 Cam would be an excellent choice for this application.Tons of torque great mid-range power.

208/221, 474"/510", 112 L.S.

The Green Rocket

On a TPI or SuperRam auto I too would think of the LPE 219 cam.

The HOT cam is completely smog friendly, mine passes with CLEANER tailpipe emissions now than when it was new (thanks to a great Tuned by Tad computer programming done on the chassis dyno) - except that it now has ~ 370 rwhp.

Thomas

PLRX

I use this cam and passed SMOG without a tune. I'd say a slightly bigger cam would also pass.

mcm95403

Great info guys, thanks! Also great to know that the SuperRam is CARB (smog-****) legal - woohoo!

As for heads, I'm not sure yet. The AFR street heads look good, as do the Edelbrocks.

I'll keep the CR low enough to run on pump gas. I have some "ideas" for some exhaust work I'd like to do among other things that should make it interesting.....(hint: I was the lead tech advisor at Flowmaster for 2 1/2 years)

0Paul Ruggeri

Yea, just call Accel and they will send you the CARB stickers. That's what I did

cv67

If you have a choice pass on the edelbrock, power comparison will be night and day.

Ive heard great things about Tuned by Tad also know him from another forum. Couple good guys here also.

j-vette

Kaliforniastan

mcm95403

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