Re: NEED info on 10.5:1 pistons

[Shawn C Meze <skerocdriver@juno.com>]

On Tue, 22 Jun 1999 15:26:05 -0400 "Verne Harris (Fnugen)"
<vwman@skyia.com> writes:

>    Hey all. I just got a line on a set of piston heads with 
>rings.....10.5:1 CR. I have 2 blocks at my disposal....a JH 8.5:1 and 
>a 1.8 16v bottom end 10:1. Other than checking for severe
wear......which
>block would be better suited?? 


What do you want to build, an 8V or a 16v?
That will determine which block you use. 


>The heads are made for the 81mm 
>bore.......and both these fit that bill. I don't want to run the KS so 
>94 octane is available and would be run....as well as a recurve dist.


I dunno about using a recurved dist. Your already going to have to run
the timming retarded (Like at 3 degrees or less) as it is to keep it out
of pingy land. 
What are the heads? 8V 16v?

 
>Can anyone advise as to what may be involved in a new piston head 
>option?? Other than take out old pin.....put in new one....I need info 
>like how much wear will be acceptable to facilitate non-boring for the
>new pistons.............and so forth. 


piston head option?? What does this mean? 
If this means you want to know which piston to use on which rods then its
simple. Use the same rods that are already in (or came with) the block.
Use the rods and crankshaft and block as a unit. Just swap over the
pistons. You should'nt need to bore out the cylinders but you should hone
the cylinders. The biggest thing to look at is at the top of the
cylinders where the rings come to a stop and move back down the cylinder,
this tends to wear a ridge. it feels like a depression. Its very bad for
loosing compression depending on how deep they are. This is when you
would need to bore the cylinders. (Or if there is a groove in the
cylinder walls.) 
Honing should restore the cylinder if everything looks good. New piston
rings are a must! 



>And can anyone ballpark a power 
>number with a 428/280 cam, header, 2" exhaust, recurve dist bigger TB 
>and the new CR ???  I am guessing at 140 without any P&P work or the 
>other sweet stuff that will likely happen later during the build. 


Id say 125-135hp is more accurate for an 8V. That cam is too big for the
stock ports. You NEED a P&P head to get any use out of the cam. 



>Soooo, 
>hoping there are some real tech heads out there willing to listen to 
>ideas and help with what they know or have done. Unless the list wants 
>to hear the advice and possible outcome.........we'll do this 
>privately. 
>       Thanks.


Heres what im currently doing for my GLi.
I have a second RD block (So I can build the motor and the car is still
drivable.) which will be bored out to 83.5mm. I found a machine shop that
will do the boring for me for $12 a cylinder. So the machine work will
cost me -$50. They will also balance the bottom end for me which is
crucial for any performance mods. 
I plan on buying/using a 2.0L stroker kit. 
Then I will P&P another HYD head for it and have the valves cut the way I
want them.
All of the other mods are already on the car. 

So when its finished and installed, anybody looking at the block will see
its just a stock RD code motor. La-la, so what. Little will they know its
a stealth 2.0L 155+hp monster.

I cant wait. Then its time to build a mad bastard smoking 8V motor for my
Scirocco! (Right after I aquire a MK-I DSP project car.)

You might want to consider some of those steps for your project?


              Shawn Meze
86' Jetta GLi           82' Scirocco GTi
The Fastest, Quickest, Cleanest and
best looking Scirocco in all of San Diego!
http://www.Geocities.com/MotorCity/Speedway/1308/index.htm

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