360 build- head help

[Firelord]

I just bought a 1976 360 from a sportsman van to build up to put in my 1973 dart sport. The engine was a 2 barrel and so far I've found the heads to be casting 3769974. Does anybody know how good these are? Is it worth rebuilding them or should I just go for the 915's aerohead racing advertises in mopar muscle (915's 3 angle valve job; 2.02 x 1.60 stainless valves; .509 lift springs, new seals,locks, retainers, bronzewall valve guides, diamond honed; $600 for the pair + shipping.) These should do well with the combination I'm thinking about:

edelbrock performer rpm intake manifold (any input on the holley, the air gap, or the M1 dual plane mopar?)
750 edelbrock performer carburator
flowmaster headers
mopar hydraulic 284 .484, 108 centerline purple camshaft
2500 rpm stall converter
shift improved 727

I'm looking to make 350-450 HP on a streetable car; 13.5's or better E.T.'s


Any recommendations?

[dave571]

600 for a set of heads like that, is a smokin deal!

The stock rebuild( with new seats) on my 516 big block heads was 600 cdn(400 us). I did all the port and port match work myself.

[rumblefish360]

350-450 hp is a big spread in HP. You'll get there OK in the parts outlined. If the heads are stock, it'll stay on the lower HP end.
Go here to check out head work/porting levels/flow levels.
http://hughesengines.com/www/hughesengines/
Go stage I port level and 9.5 compres. Max! for the street.

[Fast One]

I've just finished porting a set of 974 heads, 283 cfm @ .600 lift = 582 HP of flow, is that good enough?

Way too much for what you need but just to show they do well with the usual mods.

[Firelord]

Great results!! How much porting is that? Pocket port and bowl blend or full port? Did you do it yourself or how much did it cost you.

[rumblefish360]

You can do a bowl blend/pocket port job and get good results. Little extras like port matching are good. This ia all you need to do with that cam.

[Fast One]

That is a full porting job, all areas in the runner roof , walls / short turn / bowl / guide boss / seat cut / 2.08 intake valve, takes heaps of hours in grinding, do all porting myself, my friend has a flow bench.

Rumble is right, you don't need that much porting with that cam, 220 cfm or somewhere in that area would probably get the job done, I've had 204 cfm in those heads without doing much at all, just put 2.02 valves in with a nice angle performance cut on the seats, with some very minor work in the bowl & clean a bit of casting up, working the bowl a bit more & taking that tail out to the roof at the guide boss base plus some work at the intake entrance should be enough to generate some life in the 360 heads for that cam.

[Firelord]

Thanks guys! Sounds simple enough. Is there a book or manual you reccomend for this (I'm a first timer) or am I better off at the machine shop?

[rumblefish360]

The mag's have outlined pocket porting quit a lot. Look in mags for help on what to do. They at least have pics.
A machine shop will cost $$$. If you do it yourself....some say they wished they had payed. Try it on junk heads first.

[72Challenger]

Here's a couple web articles about home porting. Yea, I know the second one is about fords, but the theory is still good.

http://www.sa-motorsports.com/diyport.htm

http://www.fordmuscle.com/archives/2...ng/index.shtml

[tooomuch2]

Not to be skeptical but 283 cfm at 6oo lift for iron heads is really pushing it...

What flow bench were those numbers on??? If it's super flow subtract at least 20 cfm. They are not very accurate and don;t adjust for admosphere, among other things.

However, assuming those are super flow numbers that means your getting a real 260 ish on iron at 600 lift... Pretty good and realistic if you know what your doing. I would agree that with the correctly match components that 260 ish would support about 575 hp on pump gas.

based on what I have seen and read you should need about 240 cfm (match with the correct compenents) to get 500 HP using 10.5 static compression.

Other thoughts???

[Fast One]

Well oh wise one I disagree with you totally, if you don't want to believe it that's up to you, the flow bench used is exactly the same as used by the best racing teams in U.S., if it's good enough for them it's good enough for me, if a piece of equipment cost $10,000 I wouldn't be in a hurry to say it's an inaccurate piece of crap & to add to that a flow bench isn't a dyno, track times show the true potential which so far have proven them themselves beyond doubt.

[tooomuch2]

Sorry FastOne - I guess you answered my question - must be a superflow.

Read a few articles...

They are great benches just very optimistic.

To each his own...

Have fun!

[Fast One]

I care not about about magazine stories, the debate about flow benches will go on forever like many other topics in the motor world, it's just a tool to me, my first experience at the track was in 1977, so I've been around long enough to decide for myself what is good & what is bad, if it works for me that's all that matters at the end of the day.

If I thought the information was inaccurate or misleading I wouldn't touch the keyboard, not in the habit of lying or over inflating numbers so I look good, the general idea of being here is to help others but if people like you just want to piss on anything that doesn't fall into line with their opinion, I'm out of here.

[rumblefish360]

Take it easy now Fast One. tooomuch2 seems to just be sayin whats on his mind.
To the both of you I say it's a tool on which you can use to improve what you have. Base readings should be taken to find out where you've been and where your at after porting. Tools are tools. There only as good as the spinner of the wrench.
Remember, don't race flow benchs! Same head on a different bech yeilds different results. Same head on a different engine bulit to mirror specs of the 1st engine will still yeild the same increase. It's just important you understand the machine and the potential of the readings it gives.
I can see that 20 cfms is alot though.

[Firelord]

Thanks guys. The February 2002 Car craft magazine has a pretty good article on do it yourself porting of 360 heads.

[Fast One]

Just for the record a set of Chevy Aluminum race heads was tested straight out of the box on this flow bench, the heads were advertised as having 315 cfm of flow at .600 lift without any porting, they in fact actually flowed 260 cfm on this bench, several emails to the company concerned haven't been answered.

Flow testing has been done of the Edelbrock small block heads also out of the box, the figures are very much what Edelbrock advertises & also match other figures from other people I have contacted in U.S. with their own flow benches etc, Steve Dulcich has no complaints about the flow figures I have passed on or said anything to the contrary, in fact, I too have read some magazine articles on flow figures & porting of the small block factory iron heads & have noticed the figures are pretty much what I have found on this flow bench.