1.8L Motor refresh, Which piston size is best??? Options

[catsltd]

I am going to install new pistons/cylinders,and refresh the heads.
Quick question.

I am keeping the fuel injection on my 1.8L.

So should I keep the stock 93 MM cylinders,or go to a 96MM aluminum for added cooling.

If I go to the 96MM will I run into drive ability problems??.

http://aapistons.com/products/vw-porsche-9...der-kit-914-bus.
My compression went from 90 PSI hot motor throttle open to 150 PSI with a few drops of oil.
Can I do this cylinders myself???.

Thanks for any advice or suggestions.

[Mark Henry]

96mm KB pistons, iron cylinders get your cylinders bored if they're OE.
You can't do this yourself, AA cylinders are OK, but check the bore specs.

If it's a full rebuild upgrade to a 2.0 crank and rods, then you have a 2056cc.

L-jet will run fine on this combo with a WEB 73 cam, but you may lose the warm-up idle on start, so it will start sort of like carbs.
You just need to give it a bit of gas, once warm it runs perfectly.
Also KB pistons "slap" (sounds like knocking) on start up till the pistons get some heat into them. About 2-3 minutes, by 5 minutes slap is totally gone.

[Valy]

Yes you can do this yourself.
If you decide to go to 2056 you will need different pistons (higher pin) and different crank and rods (from 2L engine both). Also a longer duration cam will help bring the power out.
Keep the 1.8 heads to bump the compression up.

Before you order anything, take the cylinders apart and see what you have. It might be just rings.

[malcolm2]

L-jet will run fine on this combo with a WEB 73 cam, but you may lose the warm-up idle on start, so it will start sort of like carbs.
You just need to give it a bit of gas, once warm it runs perfectly.

Sorry for the HIGHJACK:

Mark, I have this problem. 1911 with 9550 cam, 1.8 heads with 2.0 size valves, L-jet (AFM has been tweeked several teeth) and it does not want to idle until I get to 300-ish CHT. After that, it idles ok.

From your statement, it sounds like there is no way to fix???? (IMG:style_emoticons/default/confused24.gif)

[Mark Henry]

L-jet will run fine on this combo with a WEB 73 cam, but you may lose the warm-up idle on start, so it will start sort of like carbs.
You just need to give it a bit of gas, once warm it runs perfectly.

Sorry for the HIGHJACK:

Mark, I have this problem. 1911 with 9550 cam, 1.8 heads with 2.0 size valves, L-jet (AFM has been tweeked several teeth) and it does not want to idle until I get to 300-ish CHT. After that, it idles ok.



From your statement, it sounds like there is no way to fix???? (IMG:style_emoticons/default/confused24.gif)

I didn't get to play with it enough, members car not mine, it would stall at the first stop sign, but at about the time the pistons stopped slapping (3-4 minutes) it runs like a champ.
I was thinking it was cam issue (WEB 73 or a 9550 don't remember) combined with the increase in displacement. It was a non-issue as the member was willing to live with it because the car ran perfect once warm and he lives in a rural area. Also it only did this when stone cold, park the car for 2-3 hours and it didn't seem to have the problem.

[catsltd]

I dont want to go to a 2056,But thanks Mark.

And I dont want to split the case if at all possible.
I just want to get my compression back.

Ill pull the motor and check the rings First.
But:
I am wondering if buying a set of piston and cylinders if this would be the easiest for me to do,rather than taking it in and getting honed,re-ringed etc.

I will continue to read up on build threads,but I am moving next month and want to keep down time to the minimum.

Thanks again for suggestions.

[Mark Henry]

With the pushrod tubes out remove the lifters (IMPORTANT KEEP THEM IN ORDER) take two lifters hold them face to face up to a light.

They should be be slightly convex.
If they are flat or concave, any pitting they are done and it's false economy to not rebuild the bottom end.

Good luck (IMG:style_emoticons/default/beerchug.gif)