New heads oval or rectangle
 

I have a 330 trs I am going to buy a set of edelbrock cylinder heads aluminum.
Should I buy the oval port or the rectangle port.
the pistons have a .103 dome for (open or closed chamber)
the motor was fresh two seasons ago.
new cam now 226 In / 236 Ex
I need an new exhaust to. what set up would be good.

Re: New heads oval or rectangle
 

older heavy boat approx. 5000 lbs
rpm under 5200 (cast crank)

Re: New heads oval or rectangle
 

I'd run with the ovals with that RPM range, I went with the performer rpm heads (oval) in my 427" camaro.. 515HP at 5500 I'm VERY happy with the midrange power. The cam I chose is most likely too radical for the water 610i-632e lift 296i-304e I'm not sure what the lobe seppation is, it was not on the cam card (CRANE 139741)
Rectangular port heads I've found to be outperformed by the large oval head coming out of the hole to midrange.. The rectangular heads really wake up over 5500RPM though...

Re: New heads oval or rectangle
 

Mr. Budget, What heads does the engine have as it sits now? If you are truely boating on a budget then you may still be able to retain the heads you already have. However, if you feel you must buy a set of heads, then I really believe the engine will respond better with oval port heads on a 454cid marine application engine at the RPM range as you desire.

A good aftermarket exhaust system would be something like a Stainless Marine.

Re: New heads oval or rectangle
 

ovals....the Merlins are better but a little more money. For what it costs to work on the heads you have you can but the edelbrocks guess I'd buy them.

Re: New heads oval or rectangle
 

What happened to your steal heads??

Re: New heads oval or rectangle
 

one of the steal heads was overheated a few years ago and replaced with a mix match set.
massive port job done on both heads i was unaware of this mix-match until recently.
So i have 2 separate boat anchors with good valve jobs.

Re: New heads oval or rectangle
 

kaama we are all boating on some what of a budget.
But I feel like I have less of a budget now! lol
Just waiting for lake st clair to eat the rest of the budget.
Dyno,
I was reading some of the old posts and I see that you are a part of team chaos ? where do you guys go for your machine work?

Re: New heads oval or rectangle
 

Dyno, may be right anyway. By the time you spend money to modify some GM heads it may be wiser to buy some new ones all done the way you want and ready to go.

Re: New heads oval or rectangle
 

Edelbrocks are a great set up! Did you just get the heads? they recently fixed some problems with the heads. Anyway, it's a great set up for the money. If you need help/advice let me know, we've got tons of experience with these things.

The oval ports create very good mid range which is what you need in your application. You can do some creative things with the rectangular ports if you stick to a duel plane manifold. It's all in the build! I like the rectangular port, duel plane manifold arrangement. Depending on the cam, you can build a nice usable motor that can spin up and make power when you want.

You need to talk to your engine builder.

Fionn