20v head on a Eurovan 2.5L block
10-29-2003, 07:14 PM
#1
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20v head on a Eurovan 2.5L block
is it possible, i picked up a 91 CQ parts car for cheap and so im rebuilding the motor to replace mine which has 400,000kms on and is a little tired, just curious if the 2.5L Eurovan block can be used, i know that u have to machine for the sensors and drill for the piston squirters, i know a few people that have used it in the earlier 4 and 5000s with the 10v heads, just wondering if its a waist of time for another .2 of a litre
10-29-2003, 07:33 PM
#2
Re: 20v head on a Eurovan 2.5L block
See if Chris @ Force5 will send you a picture of the driver side of the EV motor he has, would give me an idea about what sensors needed bosses drilled/tapped (i'm betting few/none).
There are a couple other things you should think about. One being, what are the wrist pin diameters of both motors. May be different. Second is, what is the distance from the wrist pin to the piston crown on both, would be less than ideal if the 7A pistons were sticking out of the EV block. The EV also has the 95.5mm stroke crank with 81mm bore cylinders, so you'll need to get the block bored for the 82.5's and honed when you have it drilled for the oil squirters. Crank will need to be balanced with the 7A pistons as well (will also help with the engine retaining the ability to rev to 7200rpm).
Something else to think about is that the Hitachi computer does not know how to deal with the extra displacement. The MAF is pretty small, injectors aren't that great flow wise, computer is not adaptive enough. One way around it is to run a custom fuel rail with larger injectors and an Apex'i S-AFC or something like that, to allow more fuel into the engine. I also have a feeling that the factory cams won't allow quite enough air in to really make a big difference in power from the 2.31L to the 2.55L motors. A set of Schrick cams would definately help out, as would the factory tube header.
There are a couple other things you should think about. One being, what are the wrist pin diameters of both motors. May be different. Second is, what is the distance from the wrist pin to the piston crown on both, would be less than ideal if the 7A pistons were sticking out of the EV block. The EV also has the 95.5mm stroke crank with 81mm bore cylinders, so you'll need to get the block bored for the 82.5's and honed when you have it drilled for the oil squirters. Crank will need to be balanced with the 7A pistons as well (will also help with the engine retaining the ability to rev to 7200rpm).
Something else to think about is that the Hitachi computer does not know how to deal with the extra displacement. The MAF is pretty small, injectors aren't that great flow wise, computer is not adaptive enough. One way around it is to run a custom fuel rail with larger injectors and an Apex'i S-AFC or something like that, to allow more fuel into the engine. I also have a feeling that the factory cams won't allow quite enough air in to really make a big difference in power from the 2.31L to the 2.55L motors. A set of Schrick cams would definately help out, as would the factory tube header.
10-29-2003, 07:47 PM
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dude..how do you know so much..your just like a fountain of endless information with no off valve!
what do you do for a living??? lol u better be like some kinda audi master mechanic!!
10-29-2003, 08:10 PM
#4
Re: dude..how do you know so much..your just like a fountain of endless information with no off valv
Nope...Nearly 24 year old engineering student (super super senior, spent too much time doing car stuff or nothing at all part of my freshman and sophomore years). I could get an Art History minor, Math minor, and Physics minor if I really wanted to with an additional full semester of classes to go along with my BSE.
I have spent pretty much my entire life around VAG products, dad had a VW/Audi/Porsche dealership from '81-92 (some of the stories he has from just the Porsche reps and Porsche dealer experiences...). I've purchased three quattros myself with my own money (same goes for the mod's I've done). I've learned a few hard Audi-modifying lessons, and wasted a good chunk of money doing so (at least $2k, probably closer to $3k in one instance). Also read up on lots things, ask people that know more than me questions, etc.
I have spent pretty much my entire life around VAG products, dad had a VW/Audi/Porsche dealership from '81-92 (some of the stories he has from just the Porsche reps and Porsche dealer experiences...). I've purchased three quattros myself with my own money (same goes for the mod's I've done). I've learned a few hard Audi-modifying lessons, and wasted a good chunk of money doing so (at least $2k, probably closer to $3k in one instance). Also read up on lots things, ask people that know more than me questions, etc.
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10-30-2003, 03:39 PM
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cool, the mechanical, easy.. Fuel delivery gets expensive
the machining doesnt cost me much at all, but to make a custom fuel rale and stuff is kinda complicated, as for cams, ive got a custom grind done for me, its a tri-grind setup so one intake opens a little before the other but the same lift, will see how it works, ive just gotta decide if its worth it to deal with fuel problems, i know that Eurospec used to have a 2.6L kit , I read it in European Car a couple of years back, i followed up on it and they had a lot of fuel problems
