Author Topic: Am I right in thinking a 1.8 8v head can bolt onto a 2.0 Bottom?  (Read 1263 times)

Offline Ben Lessani

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Hi guys,

Always in the source for more power I'm thinking of a more straightforward power boost. I've got an '86 K-Jet 1.8 8v and its still got enough poke for me (still learning to control its power). Ramping up the cubic capacity seems like an easy way to get a spot more power out of the car, what kind of gains would I see from standard (BHP / Torque), if this is even possible.

Also has anyone ever messed with the gearbox to get a longer fifth for super cruising on the motorway. Reverse gear is totally shot on my g/box so I am thinking of getting a new one or getting this one re-con'ed.

Ben

Offline DarnPB

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Yes a 2.0 bottom end can be fitted with a 1.8 head. The gain in power is modest though. About 5 or 6 bhp gain I think.
About your gearbox. A couple of options. A longer gearbox from a MKIII will so straight in. You will lose a little bit of the acceloration sparkle but have a more relaxed cruiser instead of a screaming roller skate. Or do what I did. Go to a scrappy and find a Golf 1.6 CL with a four speed +E, and remove the fifth gear. When removing the 5th gear, remember how you did it, with taking measurements too, so that you know how to change it for the one in your gearbox. You will lose about 800RPM in 5th, over the original RPM.
So you retain the GTI performance in 1st, 2nd, 3rd and 4th, but have a relaxed motorway cruiser in 5th.

Rub jonny will have more info on gearbox selection and engine block interchangeability.


THE FORUMS NUMBER ONE ANTI-FOOTBALL FAN!!!

Offline Ben Lessani

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Thanks for the quick reply. Only about 6hp - it wouldn't be worth the effort/money for that. I was expecting about a 20hp gain, oh well. With regards to my box - there isn't a single scrapyard in the whole of Scotland that has any MK2's. I constantly have to buy parts brand new £Â£Ã‚£, so I'd be out of look for that.

Offline nealey

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its not the bhp you want to chase, its torque, for the best power to money ratio though a 2.0 bottom end is the most cost effective and when combined with a few other choice mods can make a real screamer!

Offline kkh120

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Do a search on the 5th gear mod. There is a page that gives you astep by step guide on how to do this....with great pics if I remember :smiley:

Found it...

http://www.brokevw.com/5thswap.html

Quote
Rub jonny will have more info on gearbox selection and engine block interchangeability.

You were right, I new I'd seen it in one of his posts :grin:

« Last Edit: 22 August 2007, 09:25 by kkh120 »
Mk2 8v and 16v.

Always looking for bits!

Offline Mew

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You'll need to use an adapter ring for the dizzy if you use a 2e bottom end on a k-jet. Not the easiest thing to find, unless tsr make them again now?