Jack Riffle

Damn Bill, you type faster than me me, but I'll see your ten and raise you twenty.....

hacker-pschorr

Ok, gotcha. I wasn't sure if there was something else that could be set incorrectly with the vacuum advance connection. If the line is off, that does screw things up while cruising.

The more I think about it I would check timing. Sure the distributor doesn't have to move for this job. That doesn't mean the mechanic didn't take it upon himself to check timing once everything was bolted up........and set it wrong.

Start with the basics. Make sure there is vacuum on the vacuum advance line & check timing. 3,000rpm sould be 20 degrees on an 84 IIRC.

Now, on the dyno in September we will find a few extra horses with your car. Make sure you come with good gas in the car. I'll supply the colder spark plugs.

Jack Riffle

Hey Enzo, If I make it in Sept. could we find a few extra horses in mine too. Say 150 or so????

hacker-pschorr

Bring enough money I'll find a way to drop in a V10

Z

New timing belts need to be retensioned because they stretch. When they stretch they get longer. They're longer, but yet have the same number of teeth, so the teeth have to be further apart. That means the cam timing is different between a new belt and an old belt to some extent, even if the new belt is installed correctly, and there are the same number of teeth between the same points on the sprockets as there were with the old timing belt. I don't check cam timing on my 32v unless it's with a broken in timing belt, or I plan to go back and do it again once a new belt has been broken in.

Tim's car is an '84 US model. It doesn't have a crank position sensor that's used as a reference to control ignition timing. Ignition timing is determined by the position of the distributor shaft in relation to the movable part of the distributor. Turn the top of the distributor and you change the relation of it to the distributor shaft, and you change the ignition timing. The same is true if the top remains stationary and the shaft is turned. The distributor shaft is driven by the cam, which is driven by the timing belt. Change the cam timing with a different timing belt and you change the position of the distributor shaft, and therefore the ignition timing if the top of the distributor wasn't moved.

To what extent this all occurs could very well depend on the specific timing belt, and who made it, and how much it's different than the old one. It wouldn't surprise me at all if both the cam timing and ignition timing are different than they were with the old timing belt, even if the new belt was installed correctly, and the distributor was never touched.

SwayBar

There will be at least 5 guys at Road America who can do this for you.

There is no need to register if you are not participating, but you will have to sign a waiver to get through the gates.

If by chance she's offering resistance to you going to RA, you can tell her you'll be saving $160 - 1 beer when your belt is retensioned. In the meantime, she sounds like a keeper!

Imo000

Isn't one of the cam timing markings visible thogh the timing cover vent hole? I can't remember if I seen this in the past or maybe it's my imagination but remember seeing the markings for the driver side cam. I can't remmeber if this was for the 16 or the 32V either but if it is visible, it would be a very easy way to check at least one fo the cams.

Bill Ball

Imo00: The indicator on the cam belt cover vent hole was added in 86, and the gear did not get the front timing notch until 85.

85fortheDrive

Well, my neighbor, who races F4 class cars, took the OB out for a drive today. He agreed completely with me. The engine sounds great and was smooth through 5500 rpm. But indeed there was no launch at 3000 rpm as there has been in the past.

So there does seem to be a cam timing issue. I'll discuss it with the boys at Road America next Saturday.

Thanks folks, for the great advice.

SwayBar

A good check for cam timing is to do a compression test on all cylinders; one bank may have readings appreciably different than the other bank. Or you can have the case where all are too low which implies the cams may be retarded, or where all cylinders read too high, the cams advanced. From your description of power output, it appears they may be retarded.

Getting this done would really help diagnosis.

PorKen

With a single distributor engine, if the 5-8 side is on the wrong tooth, the ignition timing will be affected also. (One tooth is 15° crank.)

The notch goes with the indicator. 85 have unique gears, and a more difficult to remove 16V like 5-8 cover.