# 8V Bottom end rebuild



## 161324 (Jul 28, 2004)

I just aquired a 90 Jetta with an 8V. The engine has a new TT head, but the bottom end is blown.

I haven't torn it down yet to see what 'blown' means, but a rebuild is in order either way. I was told that the PO put 16V pistons in to the 8V, I am not sure how true that is or isn't.


I am planning on a full rebuild of the bottom end. What are my options here? I mainly worked on the VR motors, not so much the 8V.

I would probably keep the engine stock unless bigger pistons or something are cost effective.


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## shurik06_83 (Oct 19, 2006)

aba block would be ur best bet if the po changed pistons he most likely made a mess of the whole deal if the botom end is knocking then it spun a bearing and the crank is toast it will cost u more to resurface the crank then find a late 90s aba with fair ks on it


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## 161324 (Jul 28, 2004)

shurik06_83 said:


> aba block would be ur best bet if the po changed pistons he most likely made a mess of the whole deal if the botom end is knocking then it spun a bearing and the crank is toast it will cost u more to resurface the crank then find a late 90s aba with fair ks on it


I haven't even looked at it yet, so I have no idea. I can fix anything so I have no worries there.

Does anyone have a rebuild kit for these things? I know some of you guys have gone crazy with these engines, I am just looking for a solid rebuild, if I can get some extra power, then great.

Who carries the parts for the bottom end at a decent price?


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## shurik06_83 (Oct 19, 2006)

silentdub said:


> I haven't even looked at it yet, so I have no idea. I can fix anything so I have no worries there.
> 
> Does anyone have a rebuild kit for these things? I know some of you guys have gone crazy with these engines, I am just looking for a solid rebuild, if I can get some extra power, then great.
> 
> Who carries the parts for the bottom end at a decent price?


the aba is a bit more better layde out oil system u can get a whole motor for under 200$ 

it will come with a crank sensor so if u want to go digi its right their it will bold right up to ur head so u can keep stock fuel injection ignition system is the same its prety much a direct bolt in 

piston rings rod bearings main bearings are all priced same for ur as for the aba 

so if urs has a few spun bearings and the crank is toast it would be a cheap and good to go with aba 

if ur bottom end is not toast then rebuild


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## Glegor (Mar 31, 2008)

silentdub said:


> I just aquired a 90 Jetta with an 8V. The engine has a new TT head, but the bottom end is blown.
> 
> I haven't torn it down yet to see what 'blown' means, but a rebuild is in order either way. I was told that the PO put 16V pistons in to the 8V, I am not sure how true that is or isn't.
> 
> ...


16v pistons in an 8v engine makes it un-streetable, can you say 14:1 compression?

just drop in a used 2.0 ABA bottom end..

you will need two 40mm soft plugs, lengthen the exhaust a tad, a block off plate for the block breather, and either a TT distributor, or put a 4 window trigger wheel in an ABA dizzy..

the extra 200cc's of engine is worth it.. why even try and rebuild an ancient 1.8? when there are soomany good running used 2.0's out there?


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## 161324 (Jul 28, 2004)

Glegor said:


> 16v pistons in an 8v engine makes it un-streetable, can you say 14:1 compression?
> 
> just drop in a used 2.0 ABA bottom end..
> 
> ...


Understood. Makes sense.

2.0 aba bottom end here we come!


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## rjev (May 29, 2009)

also if you do a full OBD1/2 swap it makes going turbo down the road waaaay easy. or you could just do what was suggested (and what I'm planning, eventually) and just do the block and keep your head. :thumbup:


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## Glegor (Mar 31, 2008)

block swap FTW!

its so easy..

replace the cam, im shaft, and crank seals, along with the main seal while you have the engine out..

and your gonna need some soft plugs, and a saw and welder.. besides that, i think its pretty much a bolt in affair..


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## 161324 (Jul 28, 2004)

This is going to be a repair to get the car back on the road again, not to make a show car or race car out of it.

I plan on getting it reliable and selling it to a family member as her first car.

I have all the tools required to do anything, so no worries there.


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## dustinmicks (Apr 27, 2010)

Post lots of pictures 
opcorn:


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## Glegor (Mar 31, 2008)

silentdub said:


> This is going to be a repair to get the car back on the road again, not to make a show car or race car out of it.
> 
> I plan on getting it reliable and selling it to a family member as her first car.
> 
> I have all the tools required to do anything, so no worries there.


only reason i said to do the seals is because they are really easy to do with the engine out out of the car. it would suck to get it all bolted up, just to find out that the engine leaks like a sieve..


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## 161324 (Jul 28, 2004)

Glegor said:


> only reason i said to do the seals is because they are really easy to do with the engine out out of the car. it would suck to get it all bolted up, just to find out that the engine leaks like a sieve..


I agree, all seals and gaskets get replaced no matter what.

I may look for an aba now, fresh bearings and rings, along with seals/gaskets. should be golden.


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## Glegor (Mar 31, 2008)

silentdub said:


> I agree, all seals and gaskets get replaced no matter what.
> 
> I may look for an aba now, fresh bearings and rings, along with seals/gaskets. should be golden.


if you can find a decent running engine, i wouldnt touch it..

the bottom end i chose for my ABF build, was an ABA, around 100k miles, still a very clean engine.

im using the stock bearings, pistons, rods, crank, rings, everything basically how it came from the factory. 

im one of the kinda people that live by the old "if it aint broke, dont fix it" adage..

most ABAs dont get ran hard simply because its almost impossible to..

as long as the engine was maintained decent, you should be good to go.

you arent going for boost or big power, so i see no reason to rebuild the engine you get, unless it absolutely needs it.


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## g3mccotter (Mar 13, 2006)

im interested in this project how is it going?


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## stark9dubber (Mar 27, 2007)

silentdub said:


> Does anyone have a rebuild kit for these things? Who carries the parts for the bottom end at a decent price?


 i just rebuilt my 8v at school to have a solid reliable daily. i found this site www.importperformanceparts.net that sells topline engine kits which my instructor said are pretty good. and its a full rebuild kit too. all new bearings (std, 1st and 2nd undersize), pistons+rings (no charge for bigger sizes, i went .040 over, biggest available) and all gaskets/o-rings etc plus a bunch of extras that are for other engines that have different things. the kit only cost less than 300. they have other kit options that come with water pumps, oil pumps, etc. 

edit: and the pistons that come with it, im told from a friend of mine who builds mk2 racers, are 10:1 comp.


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