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Racescort
02-18-2004, 06:00 PM
What are the differances in an A1 and an A2 head? Can I fit an A1 head on an A2 engine? Would I loose any performance if I did?

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Doug
ITB Escort
[email protected]

Bildon
02-18-2004, 07:17 PM
No you can not. Solid vs. Hydro lifters and therefore the oil returns, pumps, pressures are different.

- Bill

racer_tim
02-18-2004, 09:38 PM
Actually, you can put a mech head on an A2 block, since the blocks are both the same. The only real technical difference between a hydro and a mech head is that a hydro head the valve stem is shorter and the lifter bucket is taller. Oh yea, the hydro head is also missing a cam bearing between cyl's 3-4. That's the no brainer way to tell if the head is a mech or a hydro.

You will get better performance from a mech head. Been there, done that with my LP GP motor. Long story, but the crate motor that I had dumped in back in the early 90's when the car was still a daily driver was a hydro. I gained a ton more power when I finally put in a IT prepped mech head.




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Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit (Bent)
http://linerud.myvnc.com/racing/index.html

Bildon
02-18-2004, 10:34 PM
Sorry, my brain threw a rod. I somehow equated his question to ITC engine vs. ITB engine. The 1.8s are the same.

- Bill

Dead Skunk
02-19-2004, 08:05 AM
Doug,
You're building an ITB Golf II. Why are you even asking this question? It wouldn't be legal in the class, although I was once accused of running a mechanical head. It seems to be the standard myth that nonveedubbers think you can't race a hydraulic head and we must be cheating.
Warren

racer_tim
02-19-2004, 04:15 PM
Bill, you can put a 40x33 1.8 head on a 1.6 block, but your right, the main oil return hole needs to be matched to the smaller diameter of the 1.6/1.7 block.

Now, has anybody tried to plumb the water return lines on a cross-flow head on an A1 car? That seems to be a possibility, with dual DCOE's pointed towards the front (read cold air) and having only the hot exhaust coming out of the back. There is no water jacket on the front of the head, so you'd have to have all of the return hoses from the side. Just something I'm tinkering with in my head.




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Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit (Bent)
http://linerud.myvnc.com/racing/index.html

Bill Miller
02-19-2004, 06:08 PM
Tim,

I know a couple of guys that have put 2.0 x-flow motors in A1 cars.

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MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608