DeTomaso Mailing List: July 97, Message #114
     



From: "D.Jones" <m203253@ws2200.mdc.com>

Subject: 351C - reply

Date: Mon, 07 Jul 1997 13:07:59 CDT



> What's the 351C stroking story ?



Assuming an 0.040" overbore (I'm using an Assie block), here are

a few possibilities:



 351C crank, KB112 pistons, Chrysler rods, 3.64 stroke = 373 CID



 400 crank, 1.14 pistons, Chrysler rods, 3.88 stroke = 398 CID



 400 crank, 1.14 pistons, Olds rods, 4.120 stroke = 422 CID



 351C crank, 1.14 pistons, 6.200 Eagle rods, 3.71 stroke = 380 CID



A 'net friend is an engine builder who has done a number of strokers.

He recently finished up a 430 cube 351W and it took a lot of hand

profiling to make everything fit.  However, he claims the 422 cube 

351C would be quite a bit easier. 



He also mentioned the option of the high-deck 400 block with Weiand 

adapter plates to mate the 351C manifold.  Length is exactly the same 

as a 351C.  While most 400 blocks have 429/460 bellhousing bolt patterns,

a few have smallblock patterns and will bolt right up to the ZF transaxle.

Starting with the 400 you could go to a 4.3" stroke and a .060 overbore.  

That'd be, oh, 445 CID...  or just run a stock 400 reciprocating assembly 

and the spacers for the 4V intake and heads and save a chunk of cash.



That remind me, Mike Drew (or was it Jack?) mentioned some one who 

bought a bunch of parts to do a big inch 400 and found things didn't

fit.  I mentioned this to Dave (the engine builder) and he says this 

is not uncommon and that with the right hand work everything can be

made to work.  He offered to finish that motor up for a small fee :-)



> How do you unlock the high-end breathing potential of the 351C ?



Either increase the displacement or spin it to higher rpm.

Increasing the compression helps too.

 

> What about OHC conversions ?



Why?  An engine doesn't know and doesn't care where the cams are located.



> What are all the differences between the various heads available ?



Among the iron heads there are two major differences - ports and chambers.

The 4V heads have good intake ports and bad exhaust ports.  The 2V intakes 

flow almost as much, with considerably higher velocity, and have much 

better exhausts.  The flow balance across the ports dramatically affects

the engine's camshaft requirements.



 The second difference is the combustion chamber shape.  The open

chamber head burns well, has low emissions, and is reasonably resistant

to detonation at low (under 10:1) compression ratios.  The closed

chamber heads are more sensitive to octane, but the shorter flame path

helps reduce required spark lead and makes more power.  The fuel and

timing requirements for open and closed chamber heads are much

different.



> Or, basically, how do you build a high-rpm, reliable, clean, broad

> power band killer motor on a 351C platform ... seriously,

> somebody out here should be able to provide some references for

> us newbies to read on this subject ... 



I'm leaning towards a 4V closed chamber stroker but haven't decided on

the displacement yet.  I may also play with the Aussie heads on my 

stock displacement 351C.  It only has 16,000 miles so it's kind of hard

to just yank it in favor of the stroker. 



Later,

Dan Jones



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