# 8v head on 16v block



## Sleeper-Dub (Nov 27, 2008)

so ive been reading the archived forums for a few days now but still have a few questions about this. i have a 8v jh head and a 2.0 9a 16v block. do i need to buy a 2.0 8v timing belt or a 1.8 8v timing belt? the head also has a solid 276cam i believe.. will that clear the pistons? also do i need the swap out cam sprockets and use the 2.0 one? i have all the aba 2.0 8v pullies and IM shaft just didnt know about the cam pully.
this is going into a 83 gti so will the stock cis system work for this?


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## ps2375 (Aug 13, 2003)

*Re: 8v head on 16v block (Sleeper-Dub)*

Have you looked in the hybrid forum?


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## Sleeper-Dub (Nov 27, 2008)

*Re: 8v head on 16v block (ps2375)*

yes i looked there. The search wont search for '8v' cuz its too short of a word. But every forum i look under the person building never specifies whether its a 2.0 16v or 1.8 16v or whether or not they change the cam sprocket. Plus everyone tends to contradict other people so i dont know whos right haha.


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## ABA Scirocco (May 30, 2001)

*Re: 8v head on 16v block (Sleeper-Dub)*

You need a 1.8L-8v timing belt, 8v cam, crank and intermediate shaft sprockets, you'll need to use that ABA IM shaft. If you want to run with a block mounted distributor, you'll also need an 8v oil pump and an appropriately modified distributor.
If the valve timing is correctly set up, everything clears but you need to be very careful installing the timing belt as it's pretty easy to accidentally bend a valve in the process. 
I have no idea how well it would run on stock CIS, undoubted it would need some significant tweaking.
BTW, I hope you do realize that this engine can NOT be driven on the street as it absolutely requires racing fuel due to it's very high compression ratio.


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## Sleeper-Dub (Nov 27, 2008)

*Re: 8v head on 16v block (ABA Scirocco)*

yup im aware that it wont be a daily driver as well as race gas, only street driving i would do is down to the tracks. Also i have an adjustable cam sprocket should i just keep that zeroed out so i have less of a chance to bend a valve? and i read timing is around 35 retarded (if i remember correctly) is that at idle? or static or what? 


_Modified by Sleeper-Dub at 10:15 AM 7-26-2009_


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## ABA Scirocco (May 30, 2001)

*Re: 8v head on 16v block (Sleeper-Dub)*

When you're installing the timing belt do it with the gear set at zero, just because you're less likely to make a costly mistake that way but the range of adjustment on a cam gear isn't enough to cause problems so, once you've got the timing belt properly installed, you can play around with the cam timing to find out what best suits your engine and your driving style. Cam timing is always within a few degrees of zero, advancing the cam timing moves the power band down in rpm, retarding it moves it up. 
Ignition timing will usually be around 35° before top dead centre, that's total advance at let's say 3500rpm and higher, 35° is a good starting point but exactly what is best for your engine and your type of racing may vary a bit, it's something else you need to experiment with. 
For something like an oval track car which almost never sees less than 3500 rpm except in the pits, the timing can be static, but static timing makes the engine hard to start and sucks for almost any other type of driving. It's best to have a distributor, timing computer or ignition system that generates a timing curve, 10-15° at idle ramping up to a maximum of about 35° @ 3500+rpm.


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## Sleeper-Dub (Nov 27, 2008)

*Re: 8v head on 16v block (ABA Scirocco)*


_Quote, originally posted by *ABA Scirocco* »_You need a 1.8L-8v timing belt, 8v cam, crank and intermediate shaft sprockets, you'll need to use that ABA IM shaft. If you want to run with a block mounted distributor, you'll also need an 8v oil pump and an appropriately modified distributor.
If the valve timing is correctly set up, everything clears but you need to be very careful installing the timing belt as it's pretty easy to accidentally bend a valve in the process. 
I have no idea how well it would run on stock CIS, undoubted it would need some significant tweaking.
BTW, I hope you do realize that this engine can NOT be driven on the street as it absolutely requires racing fuel due to it's very high compression ratio.

so you said i need an appropriately modified distributor... what does that mean? i currently am going to be running a aba distributor with knock sensor. is that along the lines of what you are talking about?


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## ABA Scirocco (May 30, 2001)

*Re: 8v head on 16v block (Sleeper-Dub)*

Yes but the ABA distributor as it's used in the ABA won't work with a knock sensor system, it needs to be modified. HERE's how that's done.


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## VWSoda (Mar 30, 2003)

*Re: 8v head on 16v block (ABA Scirocco)*

Try to get ahold of nitrous16v on here... I think he was running a 1.8L 16v bottom with a JH head. He did have CIS, but I believe it was a Saab or Volvo fuel distributor, and he might have had Mercedes Benz CIS injectors. I haven't seen or talked to him at the track or anything in quite some time, I dunno if he even still has the car or not but its worth a shot.


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