stroker 318

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I ported and gasket matched a set of 318 heads that I had the larger 1.88 intake and 1.60 ex valves put in. I realize these may not be the best heads for a stroker engine, but I was wondering if anyone knows there power potential. The engine is bored .40 with a 4 inch scat crank, rods, and forged icon dished pisons. Any help would be appreciated.
 
Just my opinion, but regardless of the level of porting, the engine will be out of power around 4500rpm tops and I'd be surprised if it makes much power. With a typical cam in the 225-230 range if it makes 400 hp I'd be surprised. There's just not near enough port to feed the longer stroke.
 
Thanks, I did buy these heads awhile back but they where on the motor before I stroked it , they were'nt intended for the stroker kit. I just have'nt had the extra cash to upgrade after spending it on the kit. The pistons are dished to keep the compression down, I am looking to upgrade, after the first of the year, u know christmas and all. Without buying aluminum or some high priced head do u think 360 heads would work with a decent porting and blending?
 
I think bone stock 360 heads with a performance valve job will be an improvement over ported 318 heads. However, with no porting, I'd expect it again to have peaky power, and be down a little. If you plan to upgrade later, I wouldnt put a ton of cash into the heads beyond good parts and good machine work. Maybe the basic "stage one" blending and gasket matching.
 
Are you talking about a 390 cube motor?

IMO, considering the size of the engine, I would be looking at a set of Edelbrock heads with the bowl area ported. The head is about sized right for the popular 360 engine. I think it needs just a little help for the extra cubes.

I don't muc of the RHS head.

What cam and C-ratio? What is the build for? Power wise, your looking for what?
 
I beg to differ. i know a guy running a 408 with J heads and cast intake that is running mid 11's. The cam is massive though. i would think 400hp is very doable and not bad #'s for any small block.
 
Hot rod magazine made 400hp on a 318 with magnum heads. Im sure with the right set up a stroker 318 will make more than 400hp. Not with stock heads and valves though
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It's a 318 with a .40 overbore and a 4 inch stroke scat crank and rods with icon forged dish pistons to keep compression down, small comp magnum 270 series cam, the heads have 360 intake and exhaust valves in them with a port and gasket match. I have read the magnum heads were'nt much better then the original ones other then they have a smaller combustion chamber, but need alot of porting to make them flow well? Just what I read.. I do know the heads I have are small for a stroker engine but I was hoping with the larger valves and port work they would work until I could get another set. I have read the articles on 400hp 318's an I was'nt trying to get 400 but it would be nice if I was somewhere close within 50hp or so. As for the compression ratio I think icon dish pistons have 9.5 with 62cc chambers but I'm not sure and I'm not saying that's what I have.
 
They'll work. Just not real great. Even in spite of the very small cam for a 390 cube engine and the heads it should still make 350 hp and be real torquey. As Moper said it'll probably be all done by 4500 rpm, kinda like a stock engine's rpm range. If I were you I wouldn't spend money on a set of 360 heads. They are an improvement but you'd be much much better off with aftermarket heads. Drive it with the teeny heads until you have the cash for aftermarkets. And get a bigger cam to feed it when you do the head swap.
 
To answer your question, there's no way to tell what power numbers the heads will make without having them on a flow bench. Everything else is just bench racin. The FACT is, you don't know how it will run until you flow the heads and then assemble the engine and put fire in the hole. It might surprise you.
 
StrokerScamp said:
To answer your question, there's no way to tell what power numbers the heads will make without having them on a flow bench. Everything else is just bench racin. The FACT is, you don't know how it will run until you flow the heads and then assemble the engine and put fire in the hole. It might surprise you.
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TAH-DAH, I'm with ya Rob. I've seen 318 heads flow over 270 cfm.
 
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