302 Head Suggestions

OK, pulled the 302 yesterday and mounted it onto the stand about 30 minutes ago. No where near ready to tear it apart but my bud that helped me said that I should put 351 heads onto it. Is it worth it? Thoughts?

 

did he give you a reason to do this and any problems /cost to do it? has he done it to his Maverick?

 

Depends on which 351 heads, a set off a mid 70 351 aren't going to be any better then what you have.

 

Engine situation was previous owner played with car and stuff just didn't look "right". Rear seals were leaking and I think there's water in the oil. Plus, I want to rebuild the engine so it looks nice!

 

Spending good money on a set of 351 heads is just a waste of time. The only good 351 heads were late 69/early 70 4brl heads, and you would spend quite a chunk of change to have them redone for the 302. Making any kind of HP with a SBF............it's all in the heads. Get yourself a used/new set of aluminum aftermarket heads and you will many HP ahead................IMHO

 

For that matter, if you are trying to keep to a tight budget, try and find a 96-early 97 Explorer with a V8, and snag that motor.

It will have the GT40 heads that still have an OK spark plug location for headers and a roller cam. Rebuild that 302. You will need to use the accessories from it and get a later flexplate/flywheel ... different balance weight. But you will be ahead of the old style 302.

 

yep.. as usual.. those guys are spot on.

Because.. the ONLY reason we dumped that kind of cash into 351/4bbl heads back in the day is that we didn't have many options at that time. Now you can get cheap chinese castings that will easily make 50 more horsepower.. or even factory parts that will make 40 more than even the best 351 castings.

Plus.. the 351's still need additional port work to overcome the heavily restricted exhaust. Just putting larger Chevy valves and/or split pattern cams will not fix it completely.

Again.. if budget is a concern?.. find a good as-cast part, rebuild it, and run it. If you want more power?.. aftermarket is the way to go since they start out with better baselines and you will probably end up with more cash tied up into stock parts once they are ported well enough to flow better than average numbers. Unless you can do it yourself.. porting heads ain't cheap. Good luck on the hunt.

 

Read http://mmb.maverick.to/showthread.php?t=36034 and all the replys. You can also use all the accessories, brackets, front sump oil pan, timing cover, dip stick, intake, carb, ... from your 302 on the 5.0. If you want to rebuild an engine the roller is a better deal I think but, you can probably find a serviceable 5.0 and use the long block as is.

 

well, based on y'alls advice, I'm better off sticking with my original heads. Cool!

 

what year motor is it out of ...if its from a newer 80's 90's car then i would go with some gt40 heads NOT THE gt40p heads google them!

 

1973 Maverick. Original engine but with a few modifications that need to be removed.

 

what i do know is with the gt40 heads and stock pistons your comp will drop super low even if you shave the heads down i had a set that i ported then sold them because of that reason

 

73 motors had low compression smog heads. IMO, it's worth it to get rid of them and use another toghter quench'd head that will easily add compression to wake that little motor up.

1 single point of compression rise will easily give you across the board power and efficiency gains. Not uncommon to see(and feel).. 30-40 horsies if the engine is part matched up and tuned well. Trick is to run as much compression as you can still afford to fuel correctly and you will never ever be dissapointed with the way the motor runs.

Another option would be to take the old school path to more power by simply adding some domes into those big chambers. These days domed piston designs and metallurgy are far better than they used to be and would only cost you half of a good head setup if you're pinching for power. You'd still need to fix that pitiful stock exhaust port(plus remove the smog humps if memory serves for that year) if you decide to run with stock stuff though.

When wringing upwards of 10.5 - 10.7 compression ratio out of iron heads.. it's still completely possible to find a decent "street tune" to run premium fuel without issues. With aluminum heads and a cooler t-stat you can still tune 11.5 CR to run fine on premuim.. and upwards of 10.5 CR to run on regular. Higher compression just makes everything better.. and builds big balls even on bone stock iron. What it does on warmed over or race stuff is nothing short of a miracle, IMHO.

 

I agree. This is the way to go.

 

I think what Mr. Roberts is saying is correct for an uneducated seat, but an educated seat should be able to tell the difference in 8/10HP...........IMHO