3.2 to 3.5 or 3.6

[strictly]

Cut along story short, i have a 3.2 which has been rebuilt to either 3.5 or 3.6, the motor is a complete mystery, it has run for 10,000 miles but was partially stripped on the top end before i got it due to an engine fire.

Question 1 - Can anyone help me identify if it is definatly 3.6?

The stamping on the barrels is 95ZN6, which is a 964 3.6, so the obvious answer is that it is a 3.6....

The reason i ask, is with the 3.5 having the same 100mm bore, is it not possible that this number is just a casting number. I suppose I could ask instead if anyone knows if the 3.5 Mahle, have the same casting number?

Question 2 - Cylinder height

The cylinders have a fat spacer under the base of the barrells, to offset the cylinder height, i presume to the 3.2 stroke (ive no idea what crank is fitted), but the engine was running with the chains too long (see my post in the engine rebuilding section).

I would like to adjust the deck height from 0.035 to somewhere between 0.040 and 0.060.

Does anyone know where i can get a custom spacer/shim, perferably in europe, but it dosent really matter, to match the 964 3.6 barrel - which i am presuming I have. The next step will be to remove and measure the barrels OD into the case and barrel shim, etc

[Flat6pac]

I have 3.2 and 3.3 cylinders in the pictures.
You're questioning 3.5 and 3.6
As I understand with aftermarket cylinders you can get 3.5 on a 3.2 case. Custom $s
You're showing 95xxx cylinder, opened to 98mm you get 3.4
3.6 case will have 964 casting numbers by the oil return tubes
Turbo 97

Carrera 95. Same castings on SC 95


Bruce

[jbell959]

Only way you can determine if you have a 3.5 or 3.6 is to ID the crank. Both would be fitted with 100mm pistons. I'm not sure about sources in Europe but once you determine the correct spacing there are numerous sources in the US to get shims. Best bet is to get as close to the needed size as possible to avoid stacking a bunch of them. Check with Supertech Performance, Ollies, or one of several other great engine builders that participate on these forums.

[strictly]

Thanks guys, that is intresting reading.

hmmm, so i cant really rely on the casting numbers, so as you say i need to try and id, the crank. Tommorrow, i will take the P&C's off, as that is the next step, and have a look inside the bottom end, perhaps there will be some markings on the crank i will be able to see without splitting the case

[jbell959]

Did you measure the piston? Are they 100mm?

[Jonny042]

And you should be able to measure the stroke, too.....

[strictly]

So I have done some digging today,pics below attached.

Barrels say 96ZN6 Mahle
Pistons Say 100P36 Mahle
Conrods 930.103.121.2R
Crankshaft 930.102.104.08

I presume therefore that the pistons are 964 - 3.6? The barrels must be 964, as you can see the hole spacing for the studs is bigger, and they only just fit....

QUESTION

One thing i noticed with the barrels, is that they dont but against the case, there is 2.5mm shim between the case and barrel base to set the deck height, but should the shim have not been made in such away that there is no space from the bottom of the barrel to the case where the 4 studs go? see last picture

QUESTION

I also noticed the car has twin turbo divilar studs (99310117051), They were installed to a depth of 138mm (vs 135mm in the technical bulletin). The guy who built it used two washers.

I will probally change the studs, but for the moment. I measured the depth of the hole for the stud, its about 35mm, with the studs only going in approx 25mm, should i run a cold forming tap down the hole, so i can get it a bit deeper, at least to the 135mm spec? I presume its the old loctite at the very bottom of the hole. If i switch to ARP or supertek, do i run them down until i hit the old loctite, or until they bottom out (i.e at 35mm depth)

[jbell959]

I'd post this in the Engine Rebuilding forum and you'll probably get better input. I'm not an expert by any stretch, but this combination looks odd to me.

[john walker's workshop]

To say the least.

[Quicksilver]

One detail not mentioned is that the 3.6 has a different stud spacing than the earlier engines. With a lot of work that can be modified so the 3.6 cylinders can be used with an earlier case. (But why go through the trouble?)