351 to 302 - Location Differences

[ERA2076]

Are the engine mounts for a 302 and 351 located at the same place i.e. are the horns the same and located the same for all SB's?

My headers are stamped 351. Will I be able to use them with a 302? What are the differences?

Anyone run Trick Flow heads? Do the headers fit and properly locate with the ports.

Any other differences I should be aware of with respect to converting to 302.

x-cliff

[ERA Chas]

Dunno about the mounts but the 302 is a 8.2" deck height and the 351 is 9.5". Exhaust ports higher on 351. See if T/F heads are 'standard' or raised exhaust ports on top of that.

[tcrist]

The header bolt pattern for the 302 & the 351 are the same but the deck height on the 351 is around 1" taller than the 302.

I believe the motor mount location is the same.

What this means is that if you install a 302 where the 351 was and use the 351 headers, the headers should be about 5/8" to 3/4" closer to the ground. That does not mean that you could not raise up the 302 to be higher in the frame. Do not know what else that might impact on an ERA though.

[ERA2076]

My understanding is the TF exhaust ports are raised 3/8" (1/2"?) maybe it will work out. I was wondering about any change of angle with the collector coming away from the flange or any change in tube length. I am hoping I can correct at the elbow if need.

x-chr

[ERA Chas]

Raising the 302 would change your Cg-you don't want to do that.

[ERA2076]

Originally Posted by ERA Chas

Raising the 302 would change your Cg-you don't want to do that.

Exactly - hence my question on the height of the frame horns. I'm not raising the engine. TF rotates the valves towards the center of the chamber and then raises the exhaust port for flow reasons.

x-chr

[ERA Chas]

Bob P. would know this-they build both deck-height motors into their cars.

[strictlypersonl]

All the chassis stands are the same. Since the 351 primaries are built to compensate for their higher ports (relative to the 302's), putting them on a 302 might put them on top of the chassis rail. Higher-port heads would help and, while not ideal, I might consider shimming the engine up another 1/4". That might fit.

[ERA2076]

x-chr