Heads have been cc'd. All chambers are within 1ml of each other (acceptable based on prior posts - see, I use the *search* function!).

QUESTION:
I want to put this back together this w'end and really don't want to have to stop b/c I don't have the necessary parts on hand... In order to ensure an acceptable Compression Ratio I will need to have different size shims on hand. What diff sized shims would you suggest I have on hand AND from where can I buy them so I can ahave then in my grubby lil hands by tomorrow Fri, 25-Aug) night?

BTW, I'm aiming for ~8.5:1 CR based on prior posts from Jake...1.8L heads, Webcam 73 grind, 96mm KB p/c's, 71mm stroke, D-Jet FI).

-pt

D-jet on 1.8L heads?

I hope you mean L-jet

No, D-Jet. The rebuild was off a 1.7L core w/working D-Jet FI. The 1.8L heads (AMC w/new valves, heavy duty springs, etc) were used rather than flycutting the 1.7L heads in order to handle the 96mm P/C's. The setup works.

-pt

Be prepared for a poor idle and extremely high HCs at idle, and probably less-than-satisfactory off idle transition with that cam. I know, Web Cam says it's for FI, but in the real world, it's not. The Cap'n

I've been running this setup for 4yrs. The setup works, it just requires MPS adjustment which can be done using an air fuel meter and a dyno. I've gotten to know my D-Jet very well over the years...

The Webcam 73 is very similar to RAT's 9550.

-pt

You need to measure the deck ht to determine the shim size. Deck ht is the piston at TDC to the top of the cylinder. Should be atleast .040 so the piston doesn't crash into the head. The shiming of the cylinders adjusts the deck ht/compression ratio so you need to measure what you have to setup the cr.

Geoff - Thx for the reply. We're close to what I'm looking for. I do plan on measuring the deck height (bought this tool and everything)Click to view attachment

What I want to know now, what diff size shims should I have on hand (to get to the desired 0.040" or as low asa 0.035" as Jake stated in a prior post)? I will not be able to measure the deck height til Sat and then need to have the shims on hand to get that deck height. I'm willing to buy a few different sizes in order to ensure I can get to the correct measurements. Which sizes should I have on hand to cover my ass?

I use this


I don't know how you can do this but I guess just buy several size sets from Jake and maybe you can return the unused ones?

This weekend may be a bit of a stretch.
as Geoff stated measure what you need and then order.
This is fairly simple if you can measure. But you need to get a method to torque down the cylinder to the case. ACCURATELY

I should be able to fabricate a tube/bar type of setup to act as lartge washers to set the deck height. BUT, where do I buy these shims? I left a msg @ Jake's store this morning and no luck...

Rimco has a set of 0.008" for $45 + shipping...

I'd like to get a few diff sizes, something like "small, medium, and large". I may be outta luck and just hope the deck height is in acceptable range w/o shims... Fingers crossed...

-pt

did you try aircooled.net ??

Good tip - I knew I was forgetting some shop... Aircooled.net has 10's, 20's, 30's, 50's, and 60's. Which should I have on hand? I was thinking of ordering a set of 10's, 20's, 30's, and 50's just to make sure I'm covered. I could always sell or return the ones I don't need... I'd like to get a CR of ~ 8.5. They can get the parts sent out tomorrow & would arrive on Sat. Cuts things very close but reassembly wouldn't start until Sat anyway...

Is this the only way around having to measure, order, wait for shipment, rebuild? I want to measure and rebuild on the same day...

-pt

Any other insight? Anyone ever ordered a bunch of shims and returned the unneeded ones?

Big places like Summit Racing never have a problem with doing that. I'm not so sure about the typical small aircooled operation. I've got several that I've wanted to sell since I'm not running any TIV cars. If after you measure things up if any of these sizes are the ones you need drop me an EM. I have purchased the base shims from Aircooled.net in the past and they were .002" to .009" away from the specified thickness (after de-burring and cleaning up). If I were in the need again I'd try to find another source. Maybe a local VW shop would have a pile in a box that they'd let you snoop through.

Later,
Kevin

• .0295" (2 each)
• .0290" (2 each)
• .0210" (1 each)
• .0200" (1 each)
• .0140" (1 each)
• .0085" (1 each)

Being the cheap bastard I am I got a sheet of aluminum and cut my own shims. Used a gasket cutter. Found three different thicknesses of stock. Measured everything up and was able to get each cylinder within .001 most to least.

OK, turns out I have a a set of shims ~ 0.015". I ordered a set of 0.020", 0.030", and a set of 0.050" to be safe. I figure with these different shims I should be able to get the desired CR (~8.5:1).

For what it's worth, my chambers are each ~60cc's. A few weeks ago this was all very foggy but I got it now. If the deck height on the p/c's was ZERO, I would have a CR of ~9.6:1 (71mm stroke, 96mm p/c's). Given this, if I were to put in shims of 0.040" I will end up with ~8.6:1......Bingo!!!