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Re: please gimme some adivce! :)





On Mon, 12 Jan 1998, aventari wrote:

> I'm rebuilding a JH motor for my 81 Scirocco S, and i need some advice.
> 
> On the head side of things, i'm putting on an Audi 5000 Throttle body
> (ground away the intake manifold), gasket matched intake and exhaust, stock
> valves, autotech performance springs, Ti spring retainers, G-grind,
> adjustable cam spocket, VW motorsports head gasket (for higher compression)

Deck the head - take .040" off it or so.  I've heard of people taking up
to .090" off it, but that seems scary.  I took .030" off mine to get it to
the minimum legal limit(132.55mm tall), other people have taken more off
to get to the minimum legal limit.  As far as cam timing goes, people say
that if you machine the head, your cam timing gets screwy - way I figure,
if it is within spec, the cam timing should be OK.  I guess the Autotech
gasket does the same thing, but costs more - $100 vs $30 or so at the
machine shop.  

Why titanium spring retainers?  I guess I don't see the need for them
compared to the expense - I don't know how much they cost, but I do know
how much titanium bike parts cost, and I can only guess.  If you were
building a really crazy motor, I guess I could see it(maybe), but for what
you are doing, I'd not think them necessary.  Don't know.  I can see why
pushrod engines respond well to better rockers, but the spring retainers
are light enough to begin with, and last a long time - maybe I am missing
something, but I wonder if they are really necessary.  

 
> I was also thinking of polishing the combustion camber and tops of the
> piston. Anyone done this or have any advice on doing it?
> And what kind of cam spocket should i get? cheaper the better?

Don't know.  As far as cam sprockets, I've heard good things about TTs.
Anyone know how many degrees of advance make the most power?  Curious.

> In the block, I'm having it decked, bored 20 over, line honed, crank turned
> (spun rod bearing), and I'm putting in a autotech high flow oil pump. The
> rods are gonna be machined, then shot peened (only 18 bucks for all 4!),
> and I'm getting new 'Badger' pistons from the machine shop. Anyone heard of
> these? There pretty cheap, but i think they should hold up to only 7000 or
> maybe 7500 rpm. 

I've not heard of Badger pistons - what type are they?  Lighter than
stock?  I'm leery of non-factory internal parts for VWs.  If it is a good
piston, I see no reason why it would not last.  7500rpm is probably
adequate - AFAIK, the G grind typically peaks at 5800 or 6k, so shift
points would probably be 6500 or so.  A guess, but the G grind is not
terribly aggressive, so I'd not think there'd be much need for anything
over 7k on a regular basis. 

> Oh yeah, I'm gonna use Total Seal gapless rings. Anyone ever tried these
> before? I've heard they work good any other motors (ie. no problems)

I've heard good things about them too. 

> One more thing. I'm using the 210mm clutch(stock 210 flywheel), and I taked
> to techtonics, and he said that they have a good 210 kit. It's a pressure
> plate from a 2.0l 16v mated to a stock 210 disk. Any thoughts? sounds good
> to me as long as it bolts up to the 9 bolt flywheel.

This is what I have in my GTI - it works well.  No slippage, stock
reliability, fits well.  No complaints there.

> And the machine shop (HDS in Escondito) is going to balance the rotating
> mass as an assembly. the crank, rods, pistons, flywheel, and cluch.

Are you going to lighten the flywheel?  I'd guess you could take a few
pounds off while in there and not kill reliability.

> whew! Any comments/help would be appreciated. It's about 1 month from being
> in my 'rocco! the original 190,000 mile 1.7 is showing signs of wear to say
> the least. 2 head gaskets in 5 months.

Hmmm.  Did you resurface the head after the first one went?  That's
unusual.  Good luck, let me know how it comes out - thinking about
building a new motor myself.  Mine will be basically stock(.040" overbore,
new bearings, rings, deck block, that's about it), but I'm gathering
information so I can get it right.  I've seen too many rebuilt engines
blow up after a year or two - three I can think of - and I'll be damned if
I do all that work to find out I missed something small but crucial.
That'd bother me.  The stock bottom ends seem to last a LONG time, and if
I rebuild mine, it'd better do the same.  


I.Mannix

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