400 guys: I have a 77 F250 that came with what looked like a beat up old 400 in it.... not clean paint etc... I planned on getting rid of the 400 and swapping over to a 460... then I pulled the 400 down and to my total shock it was a fresh motor, pistons stamped .060 over and crosshatch in the bore kinda fresh.

I then figured, since I have a complete setup, why not keep what I have.... but I have some questions about 400s and I figured you would be the place to ask.

I know about Tim Meyer and I look on his website and I found I have the MCC block, which is supposedly more desirable.

My build: either swap out the pistons for better compression with stock heads, or swap heads with aussie cleveland heads, or AL heads (leaning towards iron, not a huge fan of AL heads) and swap out the cam and lifters to a hydraulic roller. (I will not run non-rollers anymore in my engines) and have a fresh and powerful engine. This is a pump gas build for a work truck with 9 to 9.5:1 compression.

My questions are a follows:

If I keep the stock heads and swap pistons out will I have trouble with spark-knocking /knocking with the open chambers of the stock heads? Also, since I am .060 over.

If I swap out the heads to aussie cleveland heads what kinda compression ratio will I have? Will it be compatible with pump gas and .060 over.

Will I have trouble with overheating being .060 over with this motor?

Thanks guys

 

Ok I can answer the first question, no spark knock should not be a problem. I'm running Tmyer pistons with stock heads and 87 octane fuel with no problems. I'm not too sure About running aussie heads with stock pistons because of deck height issues, but I'm sure some of the other guys will chime in. Also running a roller cam is a great idea, I wish I would have. Good luck. I think you will be impressed by the power of a well built 400.

 

.. Don't know if T.Meyer stocks .060" over pistons... or just .030" over... maybe he can obtain and make up some... if KB makes them for him to use...

 

Thanks for all the input. I am trying to do the most cost efficient thing with the motor... The best option would be keep the short black intact, swap out the cam, and then put on new heads. I would like to get about a 9 to a 9.5:1 compression out of the motor....

 

I copy this post from another thread to help you Boba Fett because i thing it also fit here :"Compression ratio is actually higher with the stock pistons VS. Tim's Aussie head ones as the stocks have a smaller dish.

Tim's pistons do have the little "eyebrow" which comes up to zero deck providing much better Quench which theoretically would be more efficient and in reality you could run more ignition advance before pinging.

I consulted my $$$/gains calculator before deciding to stick with my stock pistons as they only had 4,000 miles on them.

I carefully calculated my cam choice based on the Dynamic compression ratio it would create with my static compression ratio, and I should be good to go on 91 pump gas.

Theory and reality are two different things though so we'll see what actually happens."

 

I agree with J Ballan as to the knocking and Cleveland heads. Not to mention intake differences, push rod length, rocker shims, valve train geometry....with Cleveland heads. Are you planning to dump the pedestal mounted rockers and go with studs/adjustable rockers?

Some Michigan cast M blocks - up to early March of 77 - were prone to water jacket cracks by the center lifter valley. Yours is A-OK, yes? Just something to check.

What cam and cam timing do you have in her now, if you know? And how has it been running for you? If you're determined to put in a roller cam, etc, then I guess that question is academic...hahaha.

With a 0.060 overbore, I would suggest a different/better than stock water pump - FlowKooler, etc.

 

That is a lot of bad info regarding the Aussie Cleveland heads. I'm running the 2v closed chamber versions and literally every single part from the old 400 stuff bolted right on.

My situation is a little unique though and it may be cheaper for you to go with Tim's pistons, read my thread for a breakdown of the cost to swap them out.

I had a buddy who had the Aussie heads sitting around, he sold them to me for $160, and they cost me about $350 on top of that at the machine shop. A set of those heads rebuilt and done for around $500 is gonna be real hard to duplicate.

I wish I could have gone roller cam but I just didn't have the budget combined with other mods I'm doing to the truck.

I'd tear those stock heads down first and see what kind of shape the guides and seats are. If they were re-done properly and don't need any $$$ thrown at them I think it'd be a no brainer to keep them.

FWIW my static Compression ratio with Aussie heads and stock pistons is around 10.25 : 1 but with a careful cam choice and my altitude Dynamic compression ratio is around 7.8 : 1 IIRC

Dynamic compression calculator = http://www.wallaceracing.com/dynamic-cr.php