larrylom

I was wondering can I put 351 Cleveland heads on my 1969 302 engine? I am doing the engine over and was wondering. How much more power will it give me and is it worth doing? Or should I just stay with the original 302 heads.
Thanks

8v-of-fury

I've heard of 390 head on a 302 with some modification... It was a big increase... I dunno bout 351 though.. No reason why it shouldn't work same engine family right?

urban_cowboy

Yes. That is basically what a Boss302 was. It takes a little work to do it though. Look up "Clevor" and you will find a ton of info about putting Clevland heads on a Windsor family block.

That being said, there is really no point in doing this. Aftermarket heads are MUCH better suited for performance and MUCH easier to install.

67mustang302

For the time, effort and difficulty involved in it, you might as well just go out and at least get some Dart Iron Eagle heads and make more power. Or even GT40 heads. Having a "high flow" head is useless on an engine that can't utilize it. And stock Cleveland heads have poor flow quality, especially for an engine as small as a 302.

THUMPIN455

390 head will not fit a 302, pretty much nothing lines up. Cleveland heads will bolt on, and really you are an Edelbrock intake, some valve notches in the piston, and plugging a square coolant hole with a round plug away from having a clevor.

I should build one just to show they can be done relatively cheap and they will make decent power. I just might once this Trans Am is out of the shop and the next 455 is done. Maybe around October... if everything works out well. I would want 347ci though. On a roller 5.0 block... yeah, lets make it interesting.

andrewmp6

Read this http://www.themustangshop.com/clevor.cfm the intake http://www.edelbrock.com/automotive_...rpm-351c.shtml it can be done but i wouldn't unless i got the heads for free most aftermarket heads are better.Chi heads makes Cleveland style heads but you gotta use there manifolds tho.

rmodel65

trick flow is making some cleve heads now too

67mustang302

Trick Flows Twisted Wedge heads follow "Cleveland" philosophy, that is to say they use a canted valve configuration to achieve better cylinder filling. If you want the top of the food chain in C heads, the Tyrannosaurus Rex of Cleve heads if you will, go with a Brodix Neal head(if you can afford it).

madmattmustangs

Cleveland 4v heads flow MASSIVE numbers with only mild porting. there valves are just as big as the 460 police interseptor motors! way bigger than any windsor set up. But you might want a big cam, intake, headers, and free flowing exhaust. And ive already shut up some of those "theres no replacement for displacement" guys by building a smart engine not a big engine.

urban_cowboy

Madmatt, Cleveland 4v heads can flow a bunch of air, but their intake runners are WAY too big (244cc) for a 302 or 351 to generate any velocity. A 2v head has a little more appropriate 205cc runner, but that is still too big for anything below a Windsor stroker. If you were running blower, or turbo, then maybe, but naturally aspirated has been proven to be problematic with these heads. Good air is not just flow. Velocity plays a key element in how much air enters the chamber and how well the fuel is atomized in that air charge. Oversized runners could work out, if you were willing to spin the motor at max rpms all the time like a circle track motor. On the street, that is not very practical. Automotive engineers were still learning what worked well when the Cleveland was built. It was way less restrictive than the Windsor heads, so it performed better, but they basically went from a tiny coffee straw (Windsor heads) to a 1" diameter straw (Cleveland). Neither are idea for drinking soda .