cvar33

It seems to me that the existance (or lack thereof) of the TI ignition module on 70 and 71 LT1s is a significant clue as to its veracity. Am I correct in assuming that 70 and 71 LT1s required TI ignition, while it was an option on 72s?

Also, does anyone have pics of the module I should be looking for in verifying a 70 -71 LT1? And if the module is missing, should I be looking for a "dangling" wire that's now unused, or holes in the fiberglass where the module was mounted? Are there any other "telltale" signs of a TI system that was removed years ago?

thanks,
Mark

moosie982

On my '71 LT-1 (bought new) the transistor ignition module was stuffed under the r/front of the car mounted on the radiator support I think or quite possibly the inner fender panel (skirt). As I remember it reminded me of a smaller version of the transmitter that some SUN Super tachs used. Dunno for sure , it was quite a while ago & now I suffer from severe "CRS". Peace,,,Moosie

Rowdy Rat

Mark,

Yes, the TI amplifier box (or the evidence that one had been installed) is a clue that the 1970 - 1972 Corvette in question could possibly be an LT-1.

Transistorized ignition was included as part of the LT-1 option for 1970 and 1971. 1972 LT-1s used a standard contact point distributor similar to what was used on other Corvettes that year.

Do a search... Somebody just posted a photo of the amplifier box not too long ago. It is mounted on the forward part of the left (driver) side inner fender. Sometimes it can be easily seen, other times not... The installation tolerances were apparently very generous.

Look for the holes... Study the AIM. There are additional clues.

Regards,

Easy Mike

Bingo. AIM will show the entire set up and list original part numbers. TI distributors and amplifiers ocassionally pop up on eBay.

cvar33

thanks for the help guys,
However, I'm sure there are plenty of real LT1s out there that have had their TI systems removed over the years for various reasons. I'm most interested in trying to find evidence of telltale signs that a TI system was once there, and hence was truely a real LT1. I assume there would still be a pigtail (plug) of some sort from the wiring harness that would still be hanging loose where the module should be.

Am I right that only 70-71s required TI ignition, and in 72 it was an option?

thanks,
Mark

Rowdy Rat

Mark,

Yes, many TI systems have been removed for various reasons over the years and yes, there are often signs that point to a factory installation even if the amplifier was removed.

The large components are the distributor, the amplifier, the coil, and the wiring harness; however, there are other changes that were made to accomodate the installation of the transistorized ignition system. Mike and I both advised getting a copy of the Assembly Instruction Manual (aka "AIM"), going to UPC K66 (toward the back), and studying what was done by the factory during installation. Studying the AIM will do a heck of alot more for your understanding than any description that we could possibly convey over the internet.

In 1970 - 1971 the transistorized ignition was part of the LT-1 option, in 1972 it was not installed on any Corvette.

Regards,

Stan Falenski

cvar33

Thanks Stan - YOU DA MAN! I hope you liked that :-)

Now I just have to rustle up an "AIM" and voila, I'll be an expert on LT1s. (insert smiley face here)

Mark

Rowdy Rat

Mark,

I don't know if that is the case either, but I would bet that you will have a very clear picture (several pictures actually) of what comprised the transistorized ignition system... Much more so than if I tried to describe it here.

I mentioned UPC K66 in my original post, but that only shows in the 1970 AIM (K66 was cancelled, but the sheets remained in the AIM)... It does appear in the UPC LT1 section for both years.

The AIM is a pretty indespensible manual. GM engineering put these together to show people on the line how to build a Corvette from the ground up. There are many vendors who sell copies of these manuals, but try to find a source that isn't using copies to make copies... Trying to read faint engineering drawings will drive you crazy.

Are you looking at a car now Mark, or do you already have one and just want to research it a bit?

Regards,

Stan Falenski

Roughrider

The K66 TI was available as an option for a number of model years...and not just Corvettes. It was available across the GM line since the early 1960's, though normally not seen outside of sales brochures. Most went on the high performance Vettes like the L71, L89, L88 and LT-1. They're pretty uncommon options outside of them.

Actually I just sold one a few weeks ago on Ebay. It was standard equipment on my '70 Avanti. I installed a new ignition system and sold the K66 and it was still working when removed.

cvar33

Stan,
I'm sorta looking at a few LT1s. A 71 warbonnet yellow in Alvin ,Tx that has been on ebay recently. A 71 gray car up in NJ at Contes dealership, and a 72 blue car (not original color). You've probably seen them all for sale - no big secret. If you have any input on them, I would be happy to listen,
thanks again
Mark

early shark

K66 Magnetic Pulse Transistorized Ignition system was mandatory equipment on the '71 LS6, along with MA6 Heavy Duty dual plate clutch option for manual transmission cars.

Brooklinite

My '72 LT-1 has TI, however it must be an add-on. I say this because when I posted a question on the NCRS board about how it's supposed to work I got hammered with responses saying it shouldn't be there.

Easy Mike

Since TI was an option, the TI wiring harness is almost certainly not part of the standard forward lamp harness. Almost certainly a separate piece with the TI set up. AIM will list the harness if it's separate/different from regular production.

Rowdy Rat

Mark,

I've looked at the photos and descriptions for the the Warbonnet yellow and Steel Cities gray cars. It's always difficult to make an analysis based on photos, but from what I can see, they both have nice paint and relatively nice interiors. I see lots of detail items that need to be addressed... Some cheap and easy, some expensive and difficult. Neither of the two ads show a photo of the stamp pad... As a potential buyer, that's something that I'd want to see and be comfortable with before handing over my money... Especially on cars like these where the engine option is determining much of the value.

If you're looking for a real LT-1 to drive and just have fun with, a many of the issues that I noted become irrelevant... If you want to have the car judged at a later date or if you are a stickler for accuracy, then you are going to have some work to do and some parts to find.

Regards,

Stan Falenski

Bullshark

Mike you are correct. The TI wiring harness is a separate piece. Also, the left front wheel inner skirt will show three holes where the TI module was mounted, unless that inner skirt was replaced due to such a thing as an accident. I don't believe anyone would go to the trouble to glass in the mounting holes if all they did was remove the module. I have saved a complete TI system off the 69 BB for reasons I really can't justify. I will probably never put it back on the car in my lifetime

Bullshark

early shark

Absolutely. This harness is completely seperate and is routed in a certain way also.