There was a question/thread in her a few weeks ago, about decking the block and the like, to get the pistons to be at the top of the bore at TDC, instead of sitting thier 8-10mm down the bore like normal.

Has anyone tried decking the head that far AND running dished pistions to keep the compresion reasonable - how did it affect the 'quench'?


PiD v3.0

The open chamber head on the SL6 combined with the negetive deck height on a 225 makes it difficult to get any quanch out of a 225 SL6.
(170 are easier)
DD

The problem is that while zero-deck works for you, dished pistons work against you. It'd probably work out to be a zero-sum game.

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Too many people who were born on third base actually believe they've hit a triple.

So, what would encourage good 'quench' in a slantie?


PiD v3.0

My good motor has a deck height of around -.020" and pistons with a dish. It don't run bad by itself, but it really, really loves the hose.

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Official Cookie and Mater Tormentor.

Okay,.. I'll need a U.S. to Aussie translation on that one,...
(I'll assume it's not a reference to Vinnie Barbarino's 'rubber hose'.)

While I'm thinking of dished Pistions - anybody know much about 'AT-2' spec slants?
All I know so far is that they're supposed to have a few differences in the crank, cam, and dished pistons to drop the compression to 8.0:1

Somewhere in my VC Valiant Sedan's history someone has droped an AT-2 slant into it, it pulls off the line hard enough to scare motorcyclists, but is all done by about 50kph in first and 85 in second (about 35mph and around 50mph respectively) where as my stock 145hp motor in my VC Wagon was slower off the line but ran to about 65kph in first and would push 100-105 in second (about 65mph).

I figure most of the difference comes from the Cam and slightly lower compression.


PiD v3.0
(Edit: Spell/grammer corrections)

He means that the motor responds nicely to Nitrous Oxide.

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David Kight
'62 Valiant Signet, White
'98 Dodge Dakota
'06 Jeep Liberty

Growing older is unavoidable but growing up is strictly optional.

The most common performance SL6 engine build-up I see these days is the long connecting rod 225 (198 con. rod)

The long con. rod allows the use of lighter pistons and also helps rod angle and piston dwell time at TDC.

To reliably do any type of quanch / squash in a SL6 you need a special closed chamber cylinder head. Take it from someone who has tried to get quanch by sticking the piston up into the head chamber... that does not work well.
DD