My 454 has an engine coding of: Either TD or TO 829 XCH rather than CWD. Does anyone know what this is? The VIN does indicate original power to be 454, but I'm unable to find and reference to this type of coding for the engine. It is stamped on the pad forward of the right side head behind the alternator.

Is it possible that this was a factory replacement engine of the original?

Any help woujld be appreciated.


Also, on a different subject. I'm looking for any source for the rear quarter window outside plastic trim. I did see a recent posting on ebay for a stainless replacement but no the original.

Thanks, George in Delaware

TO 829 XCH

T - Tonawanda Engine Plant (NY)
08 - Aug
29 - Day
XCH - LS7 GM performance parts engine

Someone installed the engine, these were only available as performance parts, never factory installed.

Nice engine in a very cool car...

Also, on a different subject. I'm looking for any source for the rear quarter window outside plastic trim. I did see a recent posting on ebay for a stainless replacement but no the original.

Thanks, George in Delaware

They are not made reproduction. The plastic one very rarely have survived this long, and if they have, most people would never try to remove them. Even the ones on me 61,000 mile garage kept 74 Monte Carlo, the trim is showing wear and effects of the sun. The best you can do is the stainless on eBay. Bug $$$.

Thanks for the help. I discovered the exhaut to be a bit messed up and short of the rear axle. Our state requires the exhaust going past the rear wheels, so the '73 now has a new dual system from manifolds to tailpipe. Looks great sounds good.
Plus, the steering wheel was to one side, so an alignment and wheel centering took car of that. Now, back to the rest of the car.

I have to run the beast thru the state inspection emmisions test. That should be a trip to failure. With the LS7 I think I'll fail the air test from the exhaust, but here's hoping I'm wrong. Hydrocarbons are hard to hide.

IIRC, hydrocarbons back in that era were around 660 ppm, good luck on your test. It won't have to pass todays standards as far as I know.

Leo, where's the Maryland Club headquarters? Thanks for the information. The exhaust came out great. Sound is a bout the same, but the pipes are the same size thru out the system. I let you know how I do in the hydro carbons.
Do you think removing the aircleaner and advancing the timing will help the test results?
No smog controls on this engine as installed at the moment.
Now I need to hunt qa local salvage yard for a front right tirn signal lens. My amber one has a hole in it.

Are there any other 1973 Chevelle's in the Maryland Club?

George,

No, I think, IIRC, that you can advance the timing a bit, turn your idle screws in about 1/8 to 1/4 turn to lean the mix, but you have to watch out for NOx if they check for that. An old trick I remember, was to take a piece of vacuum hose and run it into the car and plug it with a golf tee. When it came time to check it, take the tee out, it gives you a vacuum leak and leans out the mix some.

George,
Do you have any pics of your car?

You still have to smog a 35 year old car? Wow! I'm glad I don't live there. You don't even get an exemption for a classic car? FYI a couple of bottles of rubbing alcohol or dry gas will clean things up a little.

Retarded timing improves emission and no vacuum advance at idle
that is what the factory did to improve emissions
does not improve performance but did improve emissions