Rebuild $

[JimLill]

Motor: VW A2 8V motor

Assuming motor needs pistons/rings, bearings & typ. What is the right price to pay for

1) the parts to DIY it
2) the labor $ to have it done
3) buy a ready to go rebuilt shortblock

[joeg]

You have the tools and skills to assemble the short block?

I budget $1200 for a rebuild; I do all the assembly meaning gaping rings, checking tolerances and stuff after the parts come back from the machine shops--I use different shops for different procedures (all crankwork to one; boring and honing to another, etc.)

The $1200 includes new pistons and rings only. I have collected so many bearing sets, gasket sets and waterpumps on eBay for cheap$, they are no longer a factor.

[JimLill]

Thanks......

you mention water pump.... so you go beyond short-blck in your $$ ?

[Knestis]

Having not done one for a while until this winter, I was reminded of just how much a rebuild budget might vary - what do you want balanced (if anything), what fasteners to you want to use, etc., etc., etc.

A better way to tackle the question might be to set a budget and then ask, "How can I get the most value for that amount?"

K

[zracre]

unless you are real good at calculating comp ratios and have a machine shop at your disposal, have someone do it. if you want to learn about it, diy. If you dont have alot of money wing it!! be sure to have someone help you though! there are many good people on this site that will help you with tech questions.

[JimLill]

This might be an interesting benchmark/baseline.....

I note that brand-new factory full assembled shortblocks can be bought for $1200 delivered.

[shwah]

Too bad those won't give you the compression you want, and won't have components balanced to match the lightest stock items, and won't have head studs, and won't have ARP harware in the bottom end.

Those are all the main reasons to build an IT motor IMO. I am currently running an old crate motor that has about 60k street miles on it. It works, but I got tired of watching a Rabbit GTI motor around me on the straight at Memphis a few weeks ago (although it was pretty fun to try to get around him again before we hit the striaght again).

[joeg]

Waterpump is attached to the short block, so I add a new one into the mix.

You should give this a try. Buy some tools, read the many books on the subject (yes..."Building the Performance Small Block Chevy" or its equivalent is very helpful, even if you are dealing with a water cooled VW four banger) and go at it.

Frankly, I doubt anyone on these boards has a boring bar or Sunnen machine in their basement (and if they do, they would not be using it on a daily basis), so most of the work is going to be done by a professional shop. The adventure is more in finding the right shop and that can be an expensive and frustrating journey.

Go have some fun and dive into the assembly process.

Cheers.

[JimLill]

my definition of DIY was the assembly and "managing" of the project. Managing being the determination of need and shop selection for the machine work.

[Commy]

Do you have a machine shop in mind? I ask because I am relitively close to you, and the group that is building or VW has decided to "assemble and manage" our motor. Not send it out like I wanted to. They have a place in mind for the machining, but I am unsure of it. Just looking for more options.

[JimLill]

well I have the machine shop located... so am proceeding down a path with my spare motor.... Let them do the SB.

But the first issue will be what is the best source for "proper" pistons? Remember, this is an A2/RD motor.

TIA

-Jim

[JimLill]

unless you are real good at calculating comp ratios
[/b]

Here's something interesting..........

http://not2fast.wryday.com/turbo/compressi...pistonVolume=10 (http://not2fast.wryday.com/turbo/compression/compression.shtml?cylinderBore=81.0&cylinderStroke=86.4&gasketBore=82.5&gasketThickness=1.80&headVolume=30&pistonVolume=10)

[msogren]

Vw rebuild notes. ;
Use the factory thrust bearing, used stock bearings out of an automatic car are the best.
try total seal rings on the second groove, they work for a very long time. read the install instructions, no oil on the rings when installing. Use ATF and spinn the motor on the stand untill the gray oil is gone.
The deck of the block pulls up around the bolt holes, after a while. it is worth while to deck the block about 020.
A large piston clearance( 003 or more ) will work well with the total seal rings and will tolerate quite a bit of overheating before sticking the rings. This may save the weekend for you and the bottom end will last ;onger,overall.
Mill the head to the min # in the book, plus 030, for one recut. FWIW ,I have had very little luck with heads that have been cut because of overheating. The cam run is bent and the total power never seems as good. The chambers also are not the same size after cutting a hot head.
Take the head to a race shop and have him touch the seats very gently, maybe let you do it by hand. get new vavles, used valves are smaller in the chamber and reduce compression. hand lap the valves to the seats. put together and give them a water test. If water runs out thru the chamber, lap them more .
Spend the time to degree the cam back to the center or whatever you like . As the crank and cam get closer , by milling the block and head, the cam gets later. Some guys like it late for top end power.
I move mine ahead (2-3*) for more midrange grunt. I have found that more passing situations occur as you leave the corner and I optimize my car for this area of the track .(except Daytona)
Us e the VW windage tray and some sort of trap door or baffled pan.
Use only synthetic oil, after breaking in run. The oil temps will get high and Mobil one does not care about temp. I connect the oil temp sender wire to the water temp sender unit.
Try about 33 degrees of timing without a Knock sensor , about 35 with,
Watch the temp and look for spikes when in a long pull area of the track, this indicates too much timing usually.
Run the Golf AC radiator, remove the Tstat and block the bypass hose, use 10 percent anti freeze.
There are a few different VW heads, some are pretty bad in the exhaust ports, some are nice. Look around for the different markings and collect a few, use the best one.
cams are the same , about 4 or 5 cams came in these engines. cams can be "optimized" to the listed cam timing profiles. The cars in front are pumping at l least 175# compression and have the best cams. They are well driven .
MM


Vw rebuild notes. ;
Use the factory thrust bearing, used stock bearings out of an automatic car are the best.
try total seal rings on the second groove, they work for a very long time. read the install instructions, no oil on the rings when installing. Use ATF and spinn the motor on the stand untill the gray oil is gone.
The deck of the block pulls up around the bolt holes, after a while. it is worth while to deck the block about 020.
A large piston clearance( 003 or more ) will work well with the total seal rings and will tolerate quite a bit of overheating before sticking the rings. This may save the weekend for you and the bottom end will last ;onger,overall.
Mill the head to the min # in the book, plus 030, for one recut. FWIW ,I have had very little luck with heads that have been cut because of overheating. The cam run is bent and the total power never seems as good. The chambers also are not the same size after cutting a hot head.
Take the head to a race shop and have him touch the seats very gently, maybe let you do it by hand. get new vavles, used valves are smaller in the chamber and reduce compression. hand lap the valves to the seats. put together and give them a water test. If water runs out thru the chamber, lap them more .
Spend the time to degree the cam back to the center or whatever you like . As the crank and cam get closer , by milling the block and head, the cam gets later. Some guys like it late for top end power.
I move mine ahead (2-3*) for more midrange grunt. I have found that more passing situations occur as you leave the corner and I optimize my car for this area of the track .(except Daytona)
Us e the VW windage tray and some sort of trap door or baffled pan.
Use only synthetic oil, after breaking in run. The oil temps will get high and Mobil one does not care about temp. I connect the oil temp sender wire to the water temp sender unit.
Try about 33 degrees of timing without a Knock sensor , about 35 with,
Watch the temp and look for spikes when in a long pull area of the track, this indicates too much timing usually.
Run the Golf AC radiator, remove the Tstat and block the bypass hose, use 10 percent anti freeze.
There are a few different VW heads, some are pretty bad in the exhaust ports, some are nice. Look around for the different markings and collect a few, use the best one.
cams are the same , about 4 or 5 cams came in these engines. cams can be "optimized" to the listed cam timing profiles. The cars in front are pumping at l least 175# compression and have the best cams. They are well driven .
MM

[JimLill]

Thanks Mike..........

[JimLill]

I am back to thinking about what pistons to buy (an A2 8V motor).... and it seems like the choices are

Cast: Mahle (Brazil and Germany)? - Kolbenschmidt - and ??

Forged: Wiseco (?) and Ross (?)

I am guessing that cast are the answer, but which ones.... buy 2 sets and select matched 4???

Thoughts?

[Knestis]

I'd be very surprised if the tolerences on a set of Mahle pistons were great enough that there would be much to gain by hand-picking four of eight...

K

[JimLill]

so any suggestions where to buy them at the best price? Are the Brazil ones OK?

[msogren]

If you need pistons. you usually also need a crank. the stock pistons will weigh within the same gram and the bores are almost all straight. I have to hone the crap out of a 150 k engine to get enough bore /piston clearance that I like (3.0+-5).
The replacement Mahle pistons will need to be balanced, They are +-5 gr. But all the same bore +-.0003
The used pistons have never broke. If you have too much cash and want to go faster, than the one or two hp gain is well spent :) IMHO. MM