'm new to this web site and need a little help. The guys on chevytalk said someone here might have a better idea on what heads to use on my 283.
I'm looking to get about 380 h.p. but I'm not sure what heads to use. I have been offered a set of 882's off of a 77 or 78 Z-28 but with the big cc chambers I can't get the compression I want. Then I was told to use 305 heads because of the smaller chambers but then someone else told me not to use them because they don't flow worth a @#*#. So here I am looking for yet another opinion on the subject.

Any help would be fantastic!!

One other thing I should mention is that I am trying toi do this on a bit of a budjet, besides I only paid $15.00 for the complete engine and I don't want to stick a fortune into it.

I am thinking of putting this in a S-10 so weight of the vehicle is pretty minimal. If anyone has DD2000 try these specs....Low performance heads ported with big valves, 9.88 compression, dual plane intake, solid cam w/ .488 lift on intake and exhaust, Small tube headers with open exhaust (will probably run glass packs, 30" at least) 750 cfm carb, and oh ya bored out .030.
This combo should just top 400h.p.
Let me kow what you think......

 

305 heads are probably a good idea on that engine. No issues with the small bore, and if they are ported the newer 305 heads flow ok, for a stock head anyway.

I'm sure someone here has some other ideas for ya. Vortec heads might be an option, as well as the vette aluminum heads.

 

Getting 380 HP out of a 283 will cost you right around twice what it would cost you to get that out of a 350.

305 heads (not swirl-port TBI type) are a good choice for heads on a 283. A basic porting job would be required to get them to flow well.

But, you're going to need a lot more than heads to get 380 HP out of a 283.

 

To get 380hp out of a 283 will mean that you will have to rev it up past 7000rpm at least; and who knows if factory 305 heads will have the intake flow to support that.

Maybe you should consider looking into aftermarket heads, just remember that 283's used 60cc chambers so you want to shoot somewhere close for that number.

 

Here's something I made up for you on DD2000. It's a combo that will get you to your goal of +380HP using a 283.

Just an FYI ...... the 283 is the dotted lines. The others are what a 350 would do. The only changes I made to the 350 were larger valves (2.02/1.6) and a 750 cfm carb.

 

well??? Where is it??

 

Excellent question. He failed Pic Posting 101.

C'mon AJ... try again!

 

Getting 380 horsepower out of a 283 can be done.
And it can be done with 305 heads.

But it will take a radical camshaft and fully ported
big valve 305 heads (1.94x 1.50 valves.)
***Fully PORTED***

This motor will require a very high stall converter (8/9")
and a high rear gear ratio (4.10/4.56) because of the higher power band of the needed radical camshaft.
A 4 or 5 speed manual trans would be better.

Power will be from 4500 to 7000+ rpm
Low rpm cruise able range will suffer.

A cam like the comp 294s solid magnum would do it.
Along with a victor jr single plane intake.
Use a 750 cfm carb.

294/294 248/248 @.050" .525" lift on 110 LSA.
Use 1-5/8" long tube headers.

Compression ratio will need to be 10:1 with 92/94 octane gas.
You can shave the 305 heads some to get the cr up to where you need it. The 305 heads have the advantage of having small 58cc chambers and respond nicely to ***FULL PORTING*** and bigger valves. They are readilly available too.

This motor will be quite radical and not good on gas.

But will go like stink......

Look for 305 head casting #'s ending in 081 or 416.
The book "How to build Chevy Small Blocks on a Budget"
by David Vizard , will explain how to prepare these heads
for high performance use.

Read it , Know it... there will be a test...

The right torque converter match up and rear gearing will be critical to the success of this combination. Plan on spending some $$$'s on the converter. This is the only big $$cost factor$$ that will be different than building a 380hp 350 ci motor.

 

It won't work..... it too big.

Right after I found that out and I got kicked off-line by a phone call and evidently I forgot to try it again.

Trying........

Phooy!!!!

It's still too big. I posted it somewhere else that has bigger pic allowance.

Oh yea....... both motors were figured at .030" over.

 

thanks AJ...I expected alot more torque difference...very interesting....