just curious as to what heads you have tried on the SO lower end. I've read that you run into clearance problems with anything other than et7e heads. Im trying to convert my top end over to HO i have everything except heads right now and have found a few edelbrock and gt40 heads pretty cheap. i'm not ready to pull the engine out to change pistons yet. that is planned for later with a 347 kit. but for right now im just looking for a little extra umph, with no bog downs right off idle. also please post any prior experiences with different heads i.e. port and polished, shaving anything like that. thanks
Any heads with a max of 1.94"intake valves will work as long as you don't go over 500" lift at the valve.Trickflows are the only 2.02 valve heads that can be used with flat top pistons due to it's combustion chamber design.
So in other words if you use the stock HO cam shaft with 1.7 ratio cobra rockers you can acheive a safe .477" valve lift.
So buy up those aluminum heads,you'll be glad you did.
now that is some good news! here is another q. i was reading an article about the gt40 vs. the gt40p and it mentioned that the gt40p heads require special hedders has anyone tried these heads and is it true.
Yes, it's true. The GT40P heads use an odd spark plug angle that is not compatible -with regular 5.0 headers
What thunderchicken said.
Also if your going to build a 347 in the future you have to go with some kind of aluminum heads,otherwise you will severly be restricting you HP!
So save up for a bit and go with either twisted wedge,edelbrocks or aluminum gt40s.
I have a 5.0L magazine form the mid 90s with a head shoot out between these 3 heads on a fairly stock 93 cobra motor and the #s are as follows:
Twisted wedge 315hp
Edelbrock 311hp
Gt40 aluminums 299hp.
I have the edelbrock performer 5.0/5.8 heads with light port work sitting in my basp00get along with a slew of performane 5.0 parts,cobra upper&lower,70mmTB,76mmC&L with powerpipe,24lb injectors,kirban adj fuel pressure reg,cobra 1.7 rr rockers,3/4" intake spacer,1 5/8" shortyunegual lenght headers.
Seeing as my TC is 5.0L Ho converted already (by me) i already have the HO cam so wanted to have asome driveability with no idle problems i will just be using the 1.7rr rockers to up the lift on the stock cam to .477 at the valve but seeing you have to change the cam anyways you should maybe look into the E-cam and bump yourself upto 350hp at the crank.
yeah i have every thing except the heads and computer.(ho upper, 19# injectors, ho cam,65mm tb/egr, 70mm 19# mafs, cold air intake, pulleys, shorties, xpipe and catback duals). suprisingly enought i have been able to aquire all this in the matter of a week off ebay for 300$ buck - exhuast of course. i asked the guy at Checkers and they have a9l comps for 79.99 with military discount and core. i read you can port ho stock et7 heads to out flow the gt40's so i might just do a home port job on them. i just want something for right now untill the rebuild planned for fall or winter this year. i plan on getting the afr 185cc for the 347 but time will tell. i want to try and keep the car emission legal.
you have all this sitting in your basment or you ported the heads sitting your basment??
There's nothing wrong with cast iron heads. I have Dart sr's on my car. In fact in boosted application cast iron heads help by limiting blown head gaskets.
(as aluminum expands and contracts faster with heat disipation than cast)
I've actually made more hp with my dart's than my friends set of gt-40x's
:evilgrin: :evilgrin: :evilgrin:
Yea it's all in my basp00get,the only things i'm missing are arp head bolts and bushings for my edelbrocks,and my headers should be here next week.
Once i get that stuff,it'll be sitting underneith my hood!