I just purchased a '69 Roadster. I was told that the motor in it is a 383, Dart Iron Eagle heads stamped OM15 200 R2 and "40" welded on them which means something, but I forgot what. It has roller rockers Wiand intake, Holley 650 street avenger carb. #'s on the front of the engine are 145432832, V61701 CKZ. On the rear pad near the bell housing it says GM3970010.

Problem is I'm not familiar with this engine. Stock motor in the '69 was a 427/390 or so I'm told. It's got a 3.70 rear end. But the speedometer reads higher than the speed I'm actually going, so maybe the speedo was swapped out? Or the rear end maybe?

Anyway, what's the approximate hp and torque on this motor? What should the timing be? Best guess on the compression ratio? I noticed it diesels a few seconds after I shut it down after a run on the freeway, so maybe I need to raise the octane? Car has chrome hooker headers as well. Oil pressure is high like 50 to 70 psi.
Looks like the engine was built within the last year. Very clean. Seller said maybe 1000 miles on it.

Oh, the seller tells me the idle speed kept creeping up on him while he owned it. He's adjust it down to 900rpms and then it would creep back up on him ac couple hundred rpms. What would cause the idle speed to creep up? Maybe the distributor clamp is loose?


Steve

|UPDATED|3/26/2004 9:15:12 AM (AZT)|/UPDATED|

Not sure about all those numbers, but from what you said it sounds like a typical 350 with different heads, cam, and intake making it into a 383, or stroker as they are called by some.

Maybe someone else in the forum can help out with the other timing questions, etc. Good luck with it.

Glenn

It could have had the rear axle ratio changed but not the speedometer drive gear in the transmission. Lift the rear wheels. Put the car in neutral. Mark both rear tires and the drive shaft. Count the number of turns of the drive shaft to turn the rear wheels one turn. The number of drive shaft turns is the rear ratio. This is hard to be exact, but it will get you close enough to tell.

There are three letters on the engine followed by several numbers. This is on the top of the block just in front of the right cylinder head. It probably does not matter. The engine has been modified. You may want to call Summit Racing or Jegs Racing to help find out what you have.

Try bringing the engine to about 2500 rpm and setting the timing at about 28 or 30 degrees BTDC. This includes vacuum and mechanical advance. See what happens. My guess is you will need high octane gas due to engine mods. Just a guess.

As far as the idle creaping up, either the timing has advanced or there is a carburator problem. After inital timing setting see where the idle is. If it's okay it was likely a timing problem, if not, look at the carb. The linkage could be sticking, or the throttle plate sticking. Don't forget to check the secondary plate.

Ken Styer