shoehorn_hands

I'm sorry if this question has been beat to death. I'm trying to put together a decent 350 on an extremely tight budget. Right now I have a good running 1977 350 with 3A heads, and I'm wondering if this cam I found on Rocket Racing will work with it. It claims to be Lunati's version of the W-31 camshaft. Here are the specs:

Advertised Duration (Int/Exh): 310/310
Duration @ .050 (Int/Exh): 232/232
Gross Valve Lift (Int/Exh): .480/.480
LSA/ICL: 113/109
Valve Lash (Int/Exh): Hyd/Hyd
RPM Range: 2800-6000

This will be in a 1985 G-body (about 3300 lbs) with a TH200-4R, stock converter, 3.73 posi, non-computer Qjet, headers and true duals. I plan to port match the heads and intake, grind out the AIR bumps, and possibly block off the exhaust crossovers.

I do have a set of 1970 #6 heads laying around but I don't know if they'll fit the '77 block since the head bolts were a different size? I'm not sure.

Does anyone have any insight about this?

olds 307 and 403

That cam is way too big. Just drill out the head bolts with a 1/2" bit and one dowel hole may need enlarged on the #6 heads, obvious when you set the heads on the block. The 3A heads are terrible flowing and crack prone. The #6 heads not only flow better but will bump compression up, 68cc chamber vs 75cc. On my 76 block with the same pistons slightly milled #6 heads and .028" Rocket Racing .028" head gaskets, now on back order, gave me 9 to 1 compression. I went with a custom cam from Cutlassefi. It was 214/214 .472/.472 on a 110, way smaller and runs great. I know Smitty had a source for .011" thick custom shim gaskets that worked well with iron heads. Those would give perfect quench and 9 to 1 compression.

Fun71

I agree, that cam is WAY WAY TOO BIG.

shoehorn_hands

Ok thanks y'all. I think I've decided to keep the 1977 motor stock except for a little bit of grinding and filling on the heads. I have a whole 1970 motor that the #6 heads go with, when I start making good money again I think I want to make a W-31 clone out of it.

olds 307 and 403

The 70 block and heads are much better starting point, what shape is it in? If there are shim head gaskets, you will lower compression when you put Felpro's or any of the replacement head gaskets on. You should have 200ish horsepower with headers and duals on a stock motor. You would have needed a 2500+ stall converter with that W-31 cam.

shoehorn_hands

The 70 motor was bought in pieces but pretty solid and no rust or anything. Missing two pistons but I'll most likely go with a set of flat tops anyway. The 77 is coming out of a Firebird, 170 HP factory but if they measure it by power to the wheels then I suspect that figure has to do with the silly 2.41 rear on the bird.

svnt442

A LONG time ago in the early 90's (time is all a matter of perspective...lol) I had a 1980 Cutlass with a 1975 350 from a 4 door Cutlass. My engine was 100% stock and running through the 1980 catalytic converter and a custom 2" y-pipe, mufflers and tail pipes....and the car had a WONDERFUL 2.28 rear gear.
There was a guy with a 403 T/A that just bugged me for months to race him so one morning at about 5:00 am we went at it....and he lost.
This is more a point about the anemic nature of late 70's engines than anything else.
I have no clue on the actual condition of his engine, but it sounded fine.
The weights of the two cars were only ab out 60 lbs apart so I discounted that.

That 1970 350 when built will wake that car up, but I suspect a gear change will be in order.

olds 307 and 403

One thing you should do is all the gasket's except head gaskets, if the factory shim head gasket's are in it. The nylon timing gears fall apart, get a Cloyes timing set. There might be 25 HP in header's and exhaust. The Hedman full length or shortie's plus the Sanderson Shortie's and 2.5" exhaust will sound awesome. The Hedman full length are the cheapest I believe, don't bother with Flowtech header's, cheap junk. You will need to notch the cross member with full length header's but you will gain the most. I ran my 2.5" duals with Sanderson shorty headers all under the passenger side hump with a compact X pipe with Hooker Areochamber Muffler's exiting behind the tires on my 88 Cutlass, it sounded amazing. I moved the system over to my 70, sounds louder and not quite as good for some reason. I have the 260 and 2" od dual exhaust and it sounds good in my 88.

shoehorn_hands

You guys are extremely helpful thanks a lot for the tips