Posted by: Ken Merring ®
2001/08/07, 18:33:42
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:I would like a recommendation for what cylinder heads to buy. I have a '73 Maverick with a stock 302 and automatic transmission. I need to replace the valves and I am going to go ahead and put on some higher performance heads. I have looked at Ford Racing's cast iron GT-40P's. They are pretty reasonably priced, but are they much of an improvement over the stock heads? If I put them on, are there any other changes I should make at the same time? Or are the more expensive aftermarket heads really worth $1k-$2k (or more). By the way, what I am after is street performance and a daily driver.
:..Considering your statement above. If no cam change is being considered that will increase the high end rpm then you donnot need a great deal more air flow. An increase in compression will do more on a stock engine to give performance as well as an increase in fuel mileage. For this you can consider the earlier
289 heads with smaller combustion chambers with cleaned up valve pockets and some exhaust port work and can mill them .015 or .020". If considering any of these heads, it is wise to have hardened vale seats installed. Your 73 engine has dished pistons as well as about .035 piston crown to deck clearence, so you need more compression. Another low cost change that will add some performance is the installation of hi lift roller rockers along with the needed hardware. What they do is axcelerate the valve lift at opening and hold open a little longer before closing. This action gives a little more air to the engine at lower lifts, from the stock cam.
Should after market heads and there cost be considered, then to get the performance they can give,a cam change needs to be considered.
If stock rpm band performance increase is desired then an RV type cam will be a great improvement even with a 2 barrel carb. But do remember that this type cam will not rev much above 5-5500 rpm and would compliment the preped 289 head very nice.
This combo will give a lot of torque and throttle response.
Good luck with what ever you decide.
Ken
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