Ok so I picked up a 350 block for my RS to replace the 305. Consider this a junk yard build, the goal here is cheap cheap.

The idea now, is to make a 383 out of it, but I'm planning on keeping the compression lower (9-10:1 or so). Assuming my 305 has 1.94 intake valves in it (91 RS 305 TBI), I was planning on doing some mild porting to the heads and throwing them back on there. Camshaft will be halfway radical, decent lift, shorter duration (Still deciding on that). I have a single plane intake, but I'll probably get a more standard style aftermarket one, and top it off with a 4-barrel instead of the TBI.

I did throw a posi unit in the back and replace the 2.73s with a 3.23 ratio when I did the disc brakes on the rear.

Now both my Mustangs ran low 12.9 - 13.2 @ 109-111 leaving at idle on cheapo street tires, no cheater slicks or anything (both stick shift cars). So the Camaro needs some pepping up....

Obviously the Camaro when I'm done with it, will have less done to it and is quite a bit heavier, but what kind of 1/4 mile time would I be looking at with the 383, cam and such, but with the stock heads? My Camaro has a 700R4, stock converter, and I'd be running on street tires. Would this be good to get me into the low 14 second range?

 

Bad assumption, and bad plan. Stock LO3 heads have 1.84" intake valves, and are good for about 170 HP (well, maybe slightly more). Low-14's with those heads on a 383 would be a very, very good day, indeed.

 

Well that does put a kink in my plans, got some bad information then.

Ok still stick with my junk yard build plan here, what cars would be good donor vehicles for small block heads? There where some stock heads that came with 1.94 valves right (Are they 1.6 exhaust, or 1.54)? <-- Assuming I did hear right and I can track down some better stock heads, could I get into the 14s with them?

 

About the only decent heads you'll find with 1.94" intake valves are '87-'92 350 TPI engines, and '96-'99 350 trucks.

If you can't get into the 13's with a 350, you've done something mighty wrong. Or, don't have a lick of traction.

 

Are the 96-99 Trucks still a cast iron head, or are they aluminum?

I think I know where a 350 TransAm is at the local u-pull-it, might have to make a trip out there.

Are you saying I could probably get by without stroking the 350 ? The block I have is in really good shape, the crank I have is standard at the moment, but it should be turned, and one rod needs fixed as it spun a bearing (the rod didn't discolor or anything, just needs reconditioned).

 

The truck heads are cast iron.

I'm running mid-13's at sea level with a simple 350, 2.93 gears, higher stall, all creature comforts.

And sticky tires.

 

sense your talking about getting an intake, my vote is for the 96-99 350 Vortecs. really good heads for the price.

 

But don't ask for "Vortec" heads when you go to the JY. That tends to raise the price. Just say you're looking for '96-'99 Chevy 350 truck heads.

 

Thats the good think about a couple of the yards around here, you go pull what you want, and take it up to the office, most things they sell for scrap weight.... The downside is I have to go out in the field and pull two heads, but at least they are cheap....

 

I'm running fully ported #187 heads on my 305, with a simple tourqe cam, an Edelbrock EPS intake, Flowtech shorty headers, and a Cloyes double roller. I haven't brought the car to the dyno yet, but i'd say it makes far more than 170 horse. Yes i have rode in faster cars, but im very content with these heads. I've also heard from a very reliable source that these heads are better than double humps, due to the ease of putting 1.94" valves in these heads and the intake ports. Also i own a set of #081 heads and i don't see much advantage to these heads. The ramp on the exhaust of these paticular heads is also alot steeper than the #187s.

Check out enginekits.com for parts. They have a set of 1.94" valves around $25

 

Those reliable sources are often somebody looking to make an easy buck off the uninformed and unsuspecting.

There's nothing easier about putting 1.94" valves in 187's than in 081's. There's something to be gained by "fully porting" 187's, but as sofa might say, "lots of maze, not much cheese".

There's a big difference between the needs of a 383 and the needs of a 305.

187's for mild, something better for wild.

 

uh i wouldn't worry about this relaible source

 

One of your first statements poses a definite problem with your end goal. You said you're planning on a cheap, cheap junkyard type build. With that in mind, forget about doing a 383. That'll throw your "cheap junkyard" budget right out the window. Besides that, you can get pretty good results from one of the better 1.94/1.50, 350 factory head castings with a lot of port work on a 350, but even with major port work, they'd probably restrict a 383's performance quite a bit. In other words, there goes the "junkyard budget" again since you'd really need to pick up a set of aftermarket heads to make a 383 shine. If you pick up the deluxe porting kit from Standard Abrasives, you can get great results porting your own heads, and save a lot of money while you're at it. Make sure you know your casting #'s before you go junkyard trolling for vortec heads so you don't end up with plain old 350 truck heads. Also keep in mind you'll have to add a new intake manifold to your budget to use the vortec heads, not to mention the cost of better valve springs and machine work to the guides if you plan on running a cam over .480 lift. The spring/guide clearance problems with vortec heads and a high lift cam have been discussed in great length on the boards here. Not trying to burst your bubble by any means, just trying to give you some real world advice. Built properly, a good old 350 will make your original 305 feel like it was a 2.8 V6!

 

I'm not buying nice pieces by any means, but basically when I priced it the 383 stuff, balanced and all was under $500. The 350 I got, needs the crank turned which is $100 here in my area, the 383 crank new is $145. I either need new rods, or have at least one reconditioned, as the 350 ones I have, one spun a rod bearing.

I still need to find the numbers on the block I bought, my friend said he ran the numbers and I think he was saying it was a 70s truck block. Its a 2-bolt main block. I had planned on running studs, as I was told studs would get you 80% of the strength of a 4-bolt main block.

Since the "cheap" 383 kit comes with a bunch of stuff that I think should be replaced anyways, I thought that was a better way to go. Even if its not operating at peak performance through a set of factory heads, wouldn't it still be stronger than just a standard 350?.

Is there any problems bolting a new set of heads to my old block?

Thanks for the help so far guys!