Is there a way to figure out the year range and vehicle my L98 TPI came out of? It’s the engine that came with the 67 C10 I recently bought. From what I’ve been able to research it looks to be from a circa 1987-1990 Corvette? Am I way off on that? Is there some other identifying marks or numbers I can find on the engine to ID it properly? Thanks

 

90-91 Vette rails and plenum. Pull a valve cover see if there 113 heads.

 

How do I identify if they are the 113 aluminum heads? Are there any specific port patterns or identifying marks on it to give me a clue? I’m new to Chevy’s and still learning. Thanks

 

If you pull a valve cover, the casting number underneath will end in 113.
judging by the other visible evidence, (corvette acc, fuel rails, map sensor plenum) those will likely be 113s. Going with Tuned, looks like a 90-91 corvette. But anything could've been changed, effort was put in it to change runners too so what else they did could be hidden underneath.
Is it vitally important to know what it came from? Not really. What it is, is another ball of wax.

 

113 are aluminum angle plug and raised D port exhaust ports.

 

So, I pulled the valve cover and have Edelbrock 60859 Performance Headers...so seems someone rebuilt the engine when they put it into the truck.

 

It’s a mutt

 

Lol, yes it is...my challenge is continuing to identify all the bits and parts so I can figure out what's going on.

My "Franken-truck"

 

Fouled spark plugs seem to indicate I may have some bad valve seals...might as well replace them while I have the covers off. Any of you ever used the nylon rope method when replacing valve seals? I don't have an air compressor.

 

Get a little pancake air compressor from Harbor Freight or wherever. They're super useful for all kinds of stuff.

 

Cut the end off an old spark plug wire, lube with white lith or something and spool it in there. Easy in, easy out.
I did a smidge of research just incase those retainers were slamming into the seals. Looks ok to .575 lift so that is probably not a problem BUT those heads come with springs for a flat tappet cam for whatever reason. If that's a roller cam, it's not off to a good start. Can you see casting numbers on the block? Might at least give you an idea what cam is likely there.

 

I have done the rope method. Works fine. Spark plug wire also sounds like it would work well.

 

Ues old thread but here is my SPID

 

Thanks for the info. I've been looking for the casting numbers on the block but haven't found them yet. Probably something in the way and I don't have it on a lift...I'm just searching around under the truck.

I'll admit to being noob when it comes to some of this stuff. If I had to guess I figure it'd have a roller cam. I'm not sure I understand what you mean though about that being a problem. How are the springs different for the flat tappet cam? Are they stronger springs?

I'll look a little harder for the casting number on the block to see if that'll give me any more clues.

 

I ended up heading over to Harbor Freight today...they had some Black Friday sales going on and I got a decent little compressor for not too much $$.

I plan to do the valve seals this coming Thanksgiving weekend...wish me luck!

 

With the dipstick on the passenger side, there's hope it's a roller cam. Casting numbers are found above the bellhousing face. Casting ending in 880 or 638 are the common roller blocks. You'll also see a big GM5.7 on the drivers side of the bellhousing 'lip' if you've got what we are guessing you have.

Roller cams need a bit more spring pressure than a similar flat tappet. I can't say you have the wrong springs but the ones equipped on those heads originally aren't intended for a roller cam. (No idea why when they were clearly marketed for the 87-95 sbc vehicles)
someone may have installed the correct springs, or you could have a flat tappet cam. I'm not saying what you have but there is a potential for mixed up parts. Heck, we have no idea what the specs are on the cam which doesn't make things easier if you have to start correcting things.
Take a close look for physical damage on those seals, just incase. Fingers crossed all is well and all you need to do is put quality seals on and get back to driving.