# differences between different 8v head codes?



## R3 (Jan 20, 2002)

Just trying to get some more info on the different 1.8 8v heads. thanks


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## ABA Scirocco (May 30, 2001)

*Re: differences between different 8v head codes? (R3)*

The codes on the heads are pretty unreliable. This is becuase they are casting numbers and not part numbers. VW has often used the same casting to make different heads. I've seen different, albeit similar, heads with identical numbers.


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## A1Rocco (Oct 6, 2001)

*Re: differences between different 8v head codes? (R3)*

Be more specific?


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## ABA Scirocco (May 30, 2001)

*Re: differences between different 8v head codes? (A1Rocco)*

Okay, for example, the 84 and 86 JH heads use the same casting numbers but they use different and non-interchangable injector seats.


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## der_panzer (Apr 28, 2003)

*Re: differences between different 8v head codes? (ABA Scirocco)*








Non-interchangable injector seats? Are you sure about that? I just built an engine using an 84 JH head. It came with the plastic seats, but i removed them and I am now using the later brass "air shrouded" seats and injectors in it. The newer hardware screws right in, no problem.


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## 84_GLI_coupe (Apr 3, 2001)

*Re: differences between different 8v head codes? (der_panzer)*


_Quote, originally posted by *der_panzer* »_







Non-interchangable injector seats? Are you sure about that? I just built an engine using an 84 JH head. It came with the plastic seats, but i removed them and I am now using the later brass "air shrouded" seats and injectors in it. The newer hardware screws right in, no problem.

I'm using the later brass seats too. They're 22x1.5mm IIRC, it's been about a year since I had to worry about them.


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## der_panzer (Apr 28, 2003)

*Re: differences between different 8v head codes? (R3)*

The casting numbers are misleading. The heads for 1.8 will come in 3 basic flavors:
83-84 solid lift with 40/33 mm valves (Rabbit GTI, Scirocco)
85-up hydro with 38/33 mm (all Golf, Jetta, Cab with CIS and all Fox)
85-up hydro with 40/33 mm (all with digifant except Fox, all 85-up GTI/GLI with CIS).
Of course, the 40/33 heads are the most desirable. The 40/33 solids are getting hard to come by, but finding 40/33 hydros should be easy. All digifant cars except the Fox have the same big 40/33 hydro heads.
From what I understand, you can use any digifant or CIS head on any 1.8 8v. You just have to use the correct injector seats for your type of injectors.


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## ABA Scirocco (May 30, 2001)

*Re: differences between different 8v head codes? (der_panzer)*


_Quote, originally posted by *der_panzer* »_







Non-interchangable injector seats? Are you sure about that? I just built an engine using an 84 JH head. It came with the plastic seats, but i removed them and I am now using the later brass "air shrouded" seats and injectors in it. The newer hardware screws right in, no problem.

That's odd, I've got an 84 JH head, I tried to thread in the later brass seats but no-go, I had to go back to the dealer an pick up the plastic seats.


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## der_panzer (Apr 28, 2003)

*Re: differences between different 8v head codes? (ABA Scirocco)*

The parts ARE different between 1.7 and 1.8 solid lifter engines. The JH is a 83-84 1.8 GTI / Rocco motor, 40/33 mm valves. Are you sure you had a JH? Maybe the head is off of a 1.7.
Strange!


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## ABA Scirocco (May 30, 2001)

*Re: differences between different 8v head codes? (der_panzer)*

Absolutely positive. The head I'm using on my 2.0L block now is a JH head that came off of an 84 GTI, the head I was using is a JH head off of an 86 Scirocco. The heads are very very similar right down to the casting number but the inserts are definitely not interchangable.


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## fast84gti (Mar 2, 2003)

*Re: differences between different 8v head codes? (der_panzer)*

90 + digi foxes are big valved... I had an '88, and purchased a crashed car (90 fox) for $200 running, for the 5 speed, intake (which is better flowing than JH, even) and the larger throttle body which is on it. This type of car is good for sourcing parts for better flow in the intake/TB area... it is hydraulic, though... Todd


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## fast84gti (Mar 2, 2003)

*Re: differences between different 8v head codes? (fast84gti)*

OK, some are big valved. I think I had a Fox sport model.. But check in the junkyards if you are looking for a hydro head with 40/33 valves.... May be an overlooked car!!!! Not as beat up as a GTI or GLI..


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## A1Rocco (Oct 6, 2001)

*Re: differences between different 8v head codes? (A1Rocco)*


_Quote, originally posted by *A1Rocco* »_Be more specific?

I meant R3 but that's OK, it created an informative discussion.


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## R3 (Jan 20, 2002)

*Re: differences between different 8v head codes? (A1Rocco)*

Yeah this thread went crazy!!







all informative info though http://****************.com/smile/emthup.gif 
I was just wondering how different the valve setups are on the different heads/flow etc. 


_Modified by R3 at 8:23 PM 4-30-2003_


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## vanaguy (Oct 18, 2002)

*Re: differences between different 8v head codes? (der_panzer)*

The original head in my '88 cabby has 40/33... it's in the van now. The original head for the Audi 3A also has 40/33, and fits onto the 1.8 nicely.


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## dohc (Sep 28, 2001)

*Re: differences between different 8v head codes? (vanaguy)*

So the 1.7 Mk1 Scirocco motor had 40mm intake and 33mm exhaust?


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## ABA Scirocco (May 30, 2001)

*Re: differences between different 8v head codes? (dohc)*


_Quote, originally posted by *dohc* »_So the 1.7 Mk1 Scirocco motor had 40mm intake and 33mm exhaust?

No, the 1.7L is an old style head with TINY intake valves (34mm?) all of the 1.8L Sciroccos had the 40/33 heads


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