# 2.0 8v with 2.0t fsi pistons, high compression setup



## CharlieSix (Feb 12, 2015)

Hi! This post is to find ideas/thoughts about the setup I will do. I have a 2.0 8v jetta mk4 and I have the idea to get a high compression engine. My ideas to achieve this is the next setup:

-268/260 TT camshaft
-2.0 tsfi pistons from a BPY code vw jetta mk5. Here in Mexico is difficult to find custom pistons, and ridiculously, VW sells the OEM pistons with rods at price greater than the forged pistons and connecting rods. So there my options are:
-Buy used pistons w/rods
-I can buy a set of new pistons outside vw, but I need to buy used rods because nobody sells new connecting rods here
-Buy new pistons, and brush 1 mm from my OEM rods to fit in the pistons
-180 °F thermostat

POSSIBILITIES
-Oil cooler: I think my setup wont need extra cooling, but I can put a oil cooler
-2.0 tsfi head gasket: I think have more volume than the AZG one, but I dont know if I can use it
-1.8t head bolts: Can I use it? I want to use it because I believe they are larger and harder than the AZG

With some luck and my calcs right, at +6000 feet Mexico City is I can survive with 92 octan gas. Maybe I can put Isopropyl alcohol at the fuel

Thank you!


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## vwpat (Oct 25, 2000)

how high of compression do you want? use thinner gasket, use ABA pistons with reamed rod bushings. The others will yield 12-14:1 depending which pistons. You have to use 8V headbolts.


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## CharlieSix (Feb 12, 2015)

Maybe about 12:1, my calcs put me in this range. Im wondering if i will need head studs


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## vwjunkie747 (May 22, 2013)

I would like to know if this would work as well


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## zaskar (Jan 17, 2000)

I remember back in the day when people was rally racing mk2's, some used 9a pistons in there 8v, ive been told comp ratio is arround 14:1, they were using race fuel... considering fsi pistons have higher comp, it would put you arround 15... 

why not a 16v or 20v head swap ? I'll prefer the 20v, you could use stock euro passat 2.0 20v n/a pistons (10.5:1) euro exhaust manifold from golf 1.8 20v n/a... maybe more money, but at least you would have good gains.

im affraid with such a high comp ratio your ecu will back the timing so much that you'll loose your gain.


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## vwpat (Oct 25, 2000)

zaskar said:


> I remember back in the day when people was rally racing mk2's, some used 9a pistons in there 8v, ive been told comp ratio is arround 14:1, they were using race fuel... considering fsi pistons have higher comp, it would put you arround 15...
> 
> why not a 16v or 20v head swap ? I'll prefer the 20v, you could use stock euro passat 2.0 20v n/a pistons (10.5:1) euro exhaust manifold from golf 1.8 20v n/a... maybe more money, but at least you would have good gains.
> 
> im affraid with such a high comp ratio your ecu will back the timing so much that you'll loose your gain.


FSi is higher than 10.8:1? FSi head may have a smaller combustion chamber than a 9A head. What is this Euro Passat 2.0 20V you speak of? Does that use the ALT engine like an Audi does?


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## CharlieSix (Feb 12, 2015)

I have bought a piston set from mahle, the measure of the dish is abour 8 to 9 cc so the compression I will have is near 11.5. I have now almost everything to make the swap. My calcs say i will have a squish distance of 0.045 or the same as OEM gasket. I know that the regular 8v have a tighter quench of abut 0.033 and im afraid of having problems with rhe wider quench. Can someone tell me if i will have a rpoblem?

I bought a fsi (no turbo) used rods that are stronger than oem rods and are 21 mm pin, that match the pistons I bought

Thats the model of pistons I have:
http://i.ebayimg.com/images/g/zp0AAOSwt6ZWWR1k/s-l1600.jpg


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## CharlieSix (Feb 12, 2015)

I have made the entire rebuild, the car is amazing!! but, I have a very bad problem...
In the 2500-3000 rpm range, there is a very lightly knock :C I think I need a bigger cam or a adjustable camgear, what can i do? 

thank you!


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