[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
HELP!! Need pistons questions answered ASAP
I may be in the minority on this, but I would stay with cast.
I have seen them live under extreme boost (15psi) for long periods with no ill
effects.
>From what I have seen/read, forged are hard on rings, as I said before...
Apparently, this is the case because the expansion rate for the forged piston
is slower than cast, and therefore it causes slop in the bore when they are
cold? I can't recall... If that is true, then it would be possible that the
rings would go south before anything else. Also, IIRC, cast pistons are
slightly lighter for the same dimensions and specifications, which should help
in obvoius ways...
Can anyone else offer some more concrete reasons to stay away from forged, or
then again to argue against my already convoluted thougth process? :-)
Cheers,
David Utley
Quoting stetson <tim@unrealexpectations.ath.cx>:
> Yes that's true.....sorta.
>
> I want to do this once, the 3A swap is this seasons planned upgrade and I
> want to do it right. I want to be able to jump up and down (figuratively
> and literally) on this engine and have it grin back @ me saying, "Is that
> all you've got?"
>
> Next season might be (Depending on finances, availablity, the weather,
> etc.) TURBO time (even if just for the 5PSI I can get away w/. Perhaps I
> should be looking @ a lower compression piston as well).
>
> But this being the case, bottom line is that I need a 83mm dia. piston
> that has compression between 10.5:1 and 8.5:1 for a 144mm rod (I'm sure
> there are other considerations that I'm just too thick to appreciate @ the
> moment that have direct and serious implications.) w/ rings and maybe
> wrist pins and circlips.
>
> I would prefer hyper-whatzis ones but will gladly acccept forged.
>
> Explaining thing w/ the depth and understanding that spawns phrases like,
> "The mud was like wet dirt",
>
> Tim
>
> <LIM> mmmm, multitextured donuts....
> <knghtbrd> LIM: with fruit filling?
> <LIM> knghtbrd: chocolate cream...
>
> On Fri, 16 Apr 2004, David Utley wrote:
>
> > I might be able to offer some ideas, and although I cringe at the thought
> of
> > another debate, -BUT-, why do you want to go forged? If you are planning
> on
> > doing something extreme in the future (IE, turbo+nitrous), then I might
> could
> > understand. If I have my facts straight, forged pistons tend to be hard
> on
> > rings even after they are fully warm. If you were racing, this would not
> > matter, but I am under the impression this was for a quick DD?
> >
> > Cheers,
> > David Utley
> >
> > Quoting stetson <tim@unrealexpectations.ath.cx>:
> >
> > > K then,
> > >
> > > A rather demanding topic I know...but I'm under the gun here.
> > >
> > > So....as you know, the 3A is in the shop where it was granted a clean
> bill
> > > of health for just about everything EXCEPT the cylinder bore.
> > >
> > > That needs to be milled .50mm over stock.
> > >
> > > This means I need new pistons (the shop will not bore w/o them in hand).
> I
> > > would like to get some nice hypereutetic <sp?> or forged and the only
> > > place I'm finding for them is Autotech for........
> > >
> > > $750 !!!!!!!!!!!
> > >
> > > YEA GODS AND LITTLE FISHES!!!!!!!!!
> > >
> > > Right now for block cleaning, tolerence checking, magnafluxing, and
> boring
> > > it's costing me $260 +tax. This means if I can find a cheaper piston set
> I
> > > could perhaps get it blueprinted and balanced.
> > >
> > > I want to do this to this engine ONCE, no more. The engine may not stay
> w/
> > > this Roc but I want to have a known, proven, hardened engine @ the end
> of
> > > this fiscal blood letting that I KNOW is good.
> > >
> > > I have Dave @ Adirondack checking into pistons for me right now (Potter
> > > can't get 'em) but will appreciate any and all info or recommendations!
> > >
> > > Are there any pistons from a ABA or 2.0 16v that could be used in it's
> > > place? Weisco's site has them listed that seem to have the same diameter
> I
> > > need (83mm) and the right rod length I need (144mm) and the right
> > > compression (10.4-10.5).
> > >
> > > Any thoughts Uber-Dubbers?
> > >
> > > Burning up my mail accounts quotas,
> > >
> > > Tim
> > >
> > >
> > > New York is a jungle, they tell you. You could go further, and say that
> > > New York is a jungle. New York *is a jungle.* Beneath the columns of
> > > the old rain forest, made of melting macadam, the mean Limpopo of
> swamped
> > > Ninth Avenue bears an angry argosy of crocs and dragons, tiger fish,
> noise
> > > machines, sweating rainmakers. On the corners stand witchdoctors and
> > > headhunters, babbling voodoo-men -- the natives, the jungle-smart
> natives.
> > > And at night, under the equatorial overgrowth and heat-holding cloud
> > > cover, you hear the ragged parrot-hoot and monkeysqueak of the sirens,
> > > and then fires flower to ward off monsters. Careful: the streets are
> > > sprung with pits and nets and traps. Hire a guide. Pack your snakebite
> > > gook and your blowdart serum. Take it seriously. You have to get a
> > > bit jungle-wise.
> > > -- Martin Amis, _Money_
> > >
> > >
> > >
> > > _______________________________________________
> > > Scirocco-l mailing list
> > > Scirocco-l@scirocco.org
> > > http://neubayern.net/mailman/listinfo/scirocco-l
> > >
> >
> >
> >
> > David Utley
> > -----------
> > Cable Volkswagen
> > 405-470-3129
> > 1-800-522-6793
> >
>
>
David Utley
-----------
Cable Volkswagen
405-470-3129
1-800-522-6793