Hey guys,

I posted a little while back w/the trade/purchase of an LT4 longblock. Now I am questioning the authenticity of it - only because I can't find the part numbers located on the heads and block anywhere. This is odd, as it even has an opti bolted up front, and what looks like the stock 96 corvette oil pan, minus sensor in the side of the sump. Of course the numbers are a little hard to read, but the best I could come up with is the following:

HEADS: 10207848 or 10207846
(have the numbers 10361 and 10661A stamped on the front and back of each head)

BLOCK: 1G125327 or 18125327
(other numbers located elsewhere are C-5 327, 5.7LG, 0016.

Any help is appreciated, and thanks in advance!

t/c
Dan Y.

 

Lt4 heads are part num 12363287, with casting p/n 12555690. This info was taken frm GMPP catalog. Not sure on block numbers.

Red intake manifold? Pull the oil pan and see if 4 bolt mains. Put a degree wheel on the cam. um im sure others will have some good ideas.

http://corvetteactioncenter.com/specs/1996/lt1lt4.html
http://www.malcams.com/legacy/misc/LT4heads.htm

 

http://www.mortec.com/location.htm

Very informative on casting numbers. Check the date to make sure they were making the lt4s at the time.

Found out that lt1s and lt4s have the same casting number on the block. 10125327 for both.

 

Im sorry I dont have time to look right now. I have to go sit on 30 acres of concrete and waste 9 hours of my life, uhhh I mean I have to go to work. Check out www.lt4.com though.

 

10207643 is part number for an LT1 head, i would guess thats what you got...eeek

 

I was really hoping maybe there was more than one part number for the LT4 heads, such as maybe a slight variation between the vette LT4's and the '97 SS/Firehawk limited runs, but to no avail. The heads definitely begin w/102. What would you do? I would have gotten easily another $2500 or so for the TTA, and I have zero interest in an LT1 block/heads, hell, I coulda bought bolt-on CNC'd heads for under that plus extras. To say the least I'm a little pissed, but what would you do?

I still have:

The Turbo Trans Am's Title
Never did a bill of sale (yet)

The guys full name, and phone number to both his shop and cell phone

Written PM's and email back and forth regarding the deal

Surveillance cameras of us both unloading the engine, loading the TTA, and the engine being moved into a garage and staying there in the same place since date of sale/trade.

Think I outta go ballistic?

your thoughts welcome...

thanx for the info guys, hopefully he'll make do. Left him a PM, we'll see in the morning.

 

Well the blocks are the same so thats a mute point. Compression is different, as are the heads. Before you go causing all sorts of hell, MAKE SURE you know you are right.

What color is the intake? If its red, and turns out to be lt1 heads, i would guess the guy is either fradulant, or honestly thought it was an lt4. I think many of the lt4s out of the vettes also say "GRAND SPORT" on the throttle body.

Next i would pull the oil pan and see if its 2 or 4 bolt mains.

 

To be sure, I'm pulling the pan tomorrow. I have it on a stand up at the shop awaiting just this.

I got the long block pretty much complete, heads loosely bolted on, 1 valve cover, complete short block, optispark still attached, as is the water pump and oil pan. No sensors. No starter (bummer), and no intake.

Honestly, my first thought of it NOT being what it is supposed to be is the flexplate attached to the rear of the block, since all LT4's came with 6-speed equipped cars receiving an LT4, but GM has been wrong in the past, etc.

Also the lack of roller rockers, intake, and fuel rail have made things a little more tricky to track down, especially since I ran into the number problem not matching up earlier today.

I WANT to give the benefit of the doubt, and really, this is why I normally purchase pretty much nothing used, as it seems lately its more logical to get screwed than simply sell somebody parts outright. Just don't make any sense to me. It's a very small world.

 

Well, just pulled the heads as well as the oil pan. The heads are definitely LT1 pieces, and the flexplate attached to the crank has definitely been attached for along time, if not, the life of the engine.

The block however, has me pretty puzzled. I know there are 4-bolt main LT1's out there, especially factory replacement engines, etc. But this particular block has straight 4-bolt mains, and each journal has the number 327 marked clearly on each. I can't tell whether or not the rods are PM LT4's or not, so it looks like I may have to disassemble the entire short block to tell. Each piston has small reliefs, but I know that doesn't tell much about the shortblock.

Anybody know any other tattle-tails before I disassemble this block to know what exactly I have here?

thanks in advance.

 

I think most the vettes have the 4 bolt mains, but it was worth checking. Im getting out of my league on the rest of the stuff, but if they are lt1 heads as you say, i wouldnt bother pulling apart the shortblock. Time for war.

 

Man I hope this works out for you.
http://grandsportregistry.com/lt1vslt4.htm
http://www.malcams.com/legacy/misc/lt1lt4.html
http://www.fierolt1.com/lt1_vs_lt4_2.htm
I didnt read though them all but I hope they help.
Also there is message fourm on http://www.lt4.com/cgi-bin/bbs/config.cgi that may help you.
Good luck

 

Thanks for the advice and support guys. I talked to him on the phone yesterday, but due to a family emergency with my son, I can't pursue this till later this week.

He claims to know nothing of this, and says he is contacting the original owner to find out what he knows, bla bla.

Would you all say asking for another $1500 from him would be not enough or right on the money?

t/c
Dan Young

 

You traded a turbo trans am for the "lt4" block. Is that all that was included? Those TTAs draw big bucks around here.

 

I traded the TTA complete, even w/extra parts for $1500 cash and a supposedly complete, running <20,000 mile LT4 from a wrecked '96 Grand Sport Vette. What I got so far is a questionable short block, although it does have 4-bolt mains, and definitely LT1 stock heads, missing head bolts, etc.

The TTA had a damaged front subframe, but I also included the replacement k-member and other goodies. There is no reason in hell I should not have netted what I asked for the car, I gave the buyer a screaming deal, just wanna run quicker in the ol' '95.