DeTomaso Mailing List: July 97, Message #196
     



From: GRR456@aol.com

Subject: RE................

Date: Fri, 11 Jul 1997 10:41:03 -0400 (EDT)



All



Extended Tip plugs are probably the best all around plug, especially for the

city driving...But you cannot use them if you have about a high dome

piston...probably about 12:1 or so....as Steve mentioned.  A racing gap plug

is a J type plug gap, and that is where the electrode only covers about half

of the post that protrudes thru the porcelin..The standard type gap plug is

where the electrode covers the full post....



On the high compression race engines, they are using a surface gap type plug,

real similar to the Allison Aircraft engine plugs...Does that mean we're

going backwards? No, that means that the Allison was a very well designed

overhead cam engine...The cam's were 252 Int,  254 Exh, with about .520 lift

on 106 centers...Real close to the best type all around strong street cams

that are out today....They are 4 valves per cylinder, with each cam lobe

actuating a tandem type of rocker, just like on the current Suzuki GSX and

GSXR heads...As a matter of fact, those heads are almost a copy of the

Allison Heads....The more things change....the more they stay the

same...Regards.....Gary



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