'72 914 Track Car - Valve Adjustment Question, Valve Adjustment - 1.8L bored to 2.0L Options

[leety]

Hi I'm new to this car and trying to figure out where the exhaust valves should be set.

I was told when I acquired the car that it is a Type IV 1.8L motor bored to 2.0L

That's all I know about the motor build, not much I know.

It appears .15mm is universally accepted on intake for all type IV motors.

It appears the stock 1.8L & 2.0L motors exhaust valves are not set the same the 1.8L is at .15mm while the 2.0L is set at .20. My question is do I go .15 or .20 on the exhaust and why?

[brant]

Hi I'm new to this car and trying to figure out where the exhaust valves should be set.

I was told when I acquired the car that it is a Type IV 1.8L motor bored to 2.0L

That's all I know about the motor build, not much I know.

It appears .15mm is universally accepted on intake for all type IV motors.

It appears the stock 1.8L & 2.0L motors exhaust valves are not set the same the 1.8L is at .15mm while the 2.0L is set at .20. My question is do I go .15 or .20 on the exhaust and why?

a stock 2.0 had sodium filled exhaust valves to help with increased heat
I would follow factory settings for a sodium exhaust valve that stretches

many folks do not use sodium exhaust valves as they are more expensive than stainless steel

Many big bore engine rebuilds do not change the stock valve sizes as it is expensive to cut new valves, pockets, and seat..


did your engine builder use stainless valves? or sodium?

are your exhaust valves stock 1.8 valves size and material?
(do you have 3 bolt 2ltr heads, or 4 bolt 1.8L heads)

brant

[leety]

Hi I'm new to this car and trying to figure out where the exhaust valves should be set.

I was told when I acquired the car that it is a Type IV 1.8L motor bored to 2.0L

That's all I know about the motor build, not much I know.

It appears .15mm is universally accepted on intake for all type IV motors.

It appears the stock 1.8L & 2.0L motors exhaust valves are not set the same the 1.8L is at .15mm while the 2.0L is set at .20. My question is do I go .15 or .20 on the exhaust and why?

a stock 2.0 had sodium filled exhaust valves to help with increased heat
I would follow factory settings for a sodium exhaust valve that stretches

many folks do not use sodium exhaust valves as they are more expensive than stainless steel

Many big bore engine rebuilds do not change the stock valve sizes as it is expensive to cut new valves, pockets, and seat..


did your engine builder use stainless valves? or sodium?

are your exhaust valves stock 1.8 valves size and material?
(do you have 3 bolt 2ltr heads, or 4 bolt 1.8L heads)

brant

Hi Brant,

Fantastic points and questions.

The builder is retired and I have no way to get definite answers to those questions.

The previous owner said it has a big racing cam and a light flywheel. That's all I got from the previous owner.

The webbers are 44's which are new I replaced them.

Is there a way to visually identify which type of heads I have with the motor in the car? I have less sheet metal obscuring the view as I have an upright fan so if there's an identifier I may be able to see it.