Modified 302 vs. Stock 302.
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From: Wingo, Ky
Modified 302 vs. Stock 302.
I have a 1979 Ford F150 with a 302, bored 30 over, edelbrock performer intake, edelbrock 600 cfm carb, double roller timing chain straight up, 268 comp cam, stock converter, rebuilt c4 with shift kit.
I have a 1973 F100 with a completely stock 302.
The 73 will burn the tires down at the line. The 79 will not even attemp to spin tires. After speed is built up the 79 will run off and leave the 73 though. Both have the same size tires/wheels. The 73 actually has higher gears(3.25). 79 has (3.50).
Does the 79 with the warmed over 302 need a different converter? If so what should I go with? I don't race the trucks, I just know im not getting out of it what I should be.
I have a 1973 F100 with a completely stock 302.
The 73 will burn the tires down at the line. The 79 will not even attemp to spin tires. After speed is built up the 79 will run off and leave the 73 though. Both have the same size tires/wheels. The 73 actually has higher gears(3.25). 79 has (3.50).
Does the 79 with the warmed over 302 need a different converter? If so what should I go with? I don't race the trucks, I just know im not getting out of it what I should be.
FTE Legend
Joined: Jun 2006
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From: Ottawa, Ontario
The heads on the '73 have tiny combustion chambers resulting in relatively high static CR.. 9.5-10:1. '79 was the smog era so the heads had large combustion chambers which resulted in very low CR.. down around 8:1. I suspect the cam in the '73 also has less duration than the one in the '79 and that all adds up to a motor that produces quite a bit more low rpm TQ.
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Joined: Jan 2009
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From: East Tennessee
What is the lift and duration of your cam, btw? I'm sure a higher stall would help, since it is a 302 with, I assume, a higher RPM cam and your new intake. It never was a torque monster, and now it's even farther lol. Just wind it out.
EDIT: Now I have looked and saw that possibly the lift is around .468 or so, and couldn't find the duration.
If this cam isn't too much of a 'top end' cam and is designed for some torque, the heads could lay to blame. Maybe it's in need of a better tune. Guess I'll wait to know the cam specs.
You could just need a higher stall to get your higher powerband engine out of the whole quicker.
EDIT: Now I have looked and saw that possibly the lift is around .468 or so, and couldn't find the duration.
If this cam isn't too much of a 'top end' cam and is designed for some torque, the heads could lay to blame. Maybe it's in need of a better tune. Guess I'll wait to know the cam specs.
You could just need a higher stall to get your higher powerband engine out of the whole quicker.
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From: Wingo, Ky
Well I think the specs on the 79 302's cam is long gone, ill try to find them. I remember that it was really a towing/everyday cam, slight lope.
The 73 seems like it has all its power whenever you want it.
The 79 floored off the line won't even set you back. Now get it up to about 30-40mph and give it to her and she will jerk you back in the seat hard. I don't race it or hotrod it all the time it just bugs me that Im not getting the full potential of the mods.
Conanski, I didn't even think about the heads being different.
The 73 seems like it has all its power whenever you want it.
The 79 floored off the line won't even set you back. Now get it up to about 30-40mph and give it to her and she will jerk you back in the seat hard. I don't race it or hotrod it all the time it just bugs me that Im not getting the full potential of the mods.
Conanski, I didn't even think about the heads being different.
Cargo Master
Joined: Dec 2004
Posts: 3,362
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From: Florence, SC
Conanski, you don't miss a trick, do you?
You really know your Ford motors and what modifications work well and what doesn't.
You have helped me in the past and it just makes me happy to know that you are still here, giving members solid advice and answering their questions.
I just PMed you, and thanks!
You really know your Ford motors and what modifications work well and what doesn't.
You have helped me in the past and it just makes me happy to know that you are still here, giving members solid advice and answering their questions.
I just PMed you, and thanks!
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From: Wingo, Ky
Well I shed some new light on the story today. The 79 F150 with modified 302 engine doesn't have a comp 268 cam. Dad found the orginal spec sheet for the cam that he put in it when he rebuilt the engine.
It is a 278 Crane Cam. So I really need to ditch the stock converter?
It is a 278 Crane Cam. So I really need to ditch the stock converter?
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