I have a 1973 F-100. I had the motor rebuilt it and found it had a 1972 351 Cleveland in it -- 2V "H" code.

What was the original motor in my truck?


I had the motor rebuilt where they shaved the heads 0.10, bored it 30 over, I have a 600 4 barrel on it with an edelbrock 4 bbl into 2 bbl heads in-take manifold and have this cam in it:

Cam lift .281 (Int) .296 (exh)
Valve lift .486 (int) .512 (exh)
Lobe Ctr: 106 (int) 118 (exh)
SAE Duration 282 (int) 292 (exh)
.050 Duration: 204 (int) 214 (exh)

How much did all of this raise the horsepower do you think?

The original timing was 4 BTC. It seems way too retarded. What should it be now?

Alex

 

In '73 the VIN engine code "H" was for 390 2 barrel.
The 351 Cleveland was never offered in the F series trucks. The 351M wasn't available until the '77 model year.

 

The increase in HP could be +/-5%.

Could be more if the pistons were changed from dish to flat top say.

5% doesn't sound like much, but you should feel the extra power once the timing is corrected.

The cam, compared to the OE specs, will make a nice difference.

4 degrees BTDC is robbing power !

Try 10 degrees.

Then try 12 degrees and 14 degrees.

But don't let your total timing exceed 34-36 degrees.

Go for test drives after each small change, and you'll soon get a feel of what the best setting is.

 

Thank you on the timing. I set it to 10 btc. I run it on ethanol free 90 octane. The pistons are stock about 8.6 to 1. I am guessing it raised the hp about 15 or so like you said. I had a choice to go with 10 to 1 on the rebuild. I did not but should have.

The motor in there now I think is a 1972 351C 2v that was about 240 hp stock and out of a Grand Torino. My guess is the original was a 360 CI.

Thank you both.

 

You're welcome.

Did you find that 10 degrees woke the engine up out of a coma ?

Don't be afraid to play around with the settings.

For reference, my 351c is at 10.2 : 1.00 with idle timing at 14 degrees.

Hmm, I would have gone for the 10 to 1.

 

Yes at 4 BTDC it was about to stall. So I moved it ahead and then wrote the initial post above.

It would have only cost me an extra $100 for the 10 to 1's and I should have did it. It is a work truck (had 2,000 lbs in it yesterday) and I thought, stock plus a bit was all it needed. Needs vs wants.

Thank you again and happy new year.

 

Happy New Year to you too.

For the benefit of you, me, and anyone else reading this, let's say that it was $10,000 to bring it to 10 : 1, and not $100, as we can't afford to get upset on New Year's Eve !