durability of JH block internals and going turbo

[jdbubb@ix.netcom.com (Dan Bubb)]

ATS - Patrick Bureau wrote:
> 
> The JH 1.8 makes 90HP,a JH/3A (PP Head w valve Job)w/G grin Cam, Header is
> expected to pull out 130-150HP, perhaps not 200HP but for air aspired that
> is pretty damn good for an 8v, considering a 16v give out 129HP. would you
> not count that as huge difference in power?

You know I don't want to brag here ;^), but two weeks ago my 2.0 NA 8V
laid down 132 uncorrected WHP and 126 lb-ft on the NGP dyno, so I'm well
aware of the increase in power the extra 200cc with all the mods makes.
I'm just saying if you're using a turbo then you can get more than
enough power from the 1.8 JH if you have fuel and ignition right to make
more power than a Scirocco can reasonably use. So, in this case having a
2.0 isn't mandatory the way it is with an NA engine.
> 
> Yes the 10.1 compression issue is one that I am trying to figure out as
> well. the only thing I can think of is getting Forged pistons and get the
> ones that would drop the pressure to a reasonable 9/9.2:1, though I think
> this would make the turbo setup restricted in how much boost can pass
> through it before blowing something.

It is my understanding that the stock ABA piston can be machined to
lower compression to 9.2 for use in a forced induction engine.
BUT, I don't know if the same is true of the 3A piston and I also don't
know if this compromises strength and limits maximum boost.

> 
> 3a block Etka Audi model 90 car year 1992-1987
> 
> ATS - Patrick Bureau - txrocco@sbcglobal.net
> 
> =>-----Original Message-----
> =>From: scirocco-l-admin@scirocco.org
> =>[mailto:scirocco-l-admin@scirocco.org]On Behalf Of Dan Bubb
> =>Sent: Tuesday, October 29, 2002 7:01 AM
> =>To: Jeff Toomasson
> =>Cc: scirocco-l@scirocco.org
> =>Subject: Re: durability of JH block internals and going turbo
> =>
> =>
> =>As far as I know the JH and 3A rods are the same length at 144mm center
> =>to center. The extra stroke is accomodated by moving the piston pin a
> =>little higher in the piston.
> =>The JH really is a good starting point cause it's rugged and it has a
> =>low compression ratio. The 3A is good because of the greater
> =>displacement (which probably won't make a huge difference in ulitmate
> =>power, but will be alot more driveable off boost), I think it has piston
> =>oil squirters (although I can't find the 3A in ETKA to save my ass) but
> =>it's really big drawback for a turbo application is the 10:1 CR. So,
> 
> <trimmed a little.. was getting long>
> 
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