Hi.
Please can you help and advise me on what you think I should do?

I have a 1977 L48 manual engine numbers matching, currently being renovated.
It will Not be painted in its orignal colour.
The engine smokes on startup, backfires and continues to smoke(blue) when warm.

I have been offered a 1972 LT1 engine that has never been started since its rebuild, with the following spec:

LT1 block
4 bolt Main Bearing Crank
Big jornal Crank
Full Engine balance inc flywheel and clutch
Heads have been ported and have standard valves
268 Compcam with hydralic lifters
Roller valve gear
Torker II inlet manifold
Holly 750cfm carb with vacuum secondary
4 Branch stainless steel headers
Mallory duel point distributer
Edelbrook high clearence rocker covers
High volume high pressure oil pump
steel duplex timing chain and gears
Chrome sump, chrome timing case
Short water pump
Aluminium Belt pulleys
Chrome air cleaner

I think is has a compression ratio of 9.35 - 1


It also comes with the following spares:

2 big valve heads- not ported
1 pair of Chrome Moroso rocker covers
Spare carb,
Low mileage cam followers and gear

(it is being offered to me for $2,730 and he will help me fit it)

The questions are,
1. Do I buy this engine and mothball mine?
2. Does this sound like a good spec for an engine and what sort of HP would I expect from it
2. Will it fit under my Hood?
3. or do I Spend money on my own engine with 90,000miles on the clock.

Many thanks Jerry

 

Wow, kind of a tough choice. If you can get this new engine at a good price and you trust the builder that will be your best short term deal, you can always rebuild the existing later.

 

LT1 block ? Are the numbers on the block to prove this -otherwise its "just" small block with high perf. parts installed? If it does have the numbers buy it and find the LT1 it goes in sell it and buy a crate motor.I think there are less unknowns with the crate motors.They are usually plus or minus 5hp of advertised HP.Other motors unless dynoed are estimated.

 

Sorry forgot to mention it, it is a small block motor.

 

Yes but its "just" a small block without the numbers.

 

No, you don't want that LT-1... But it would go great in my '72 Z28!

Seriously though, that sounds like a nice engine. The one pain about the original LT was lashing those mechanical lifter valves every few thousand miles. All you should have to worry about on that setup is high octane gas and normal tune ups.

As far as mounting, I don't think you'll have a problem. It should drop right in. If he'll help you put it in, even better. I'd do it. If you won't I will.

 

Do you have an estimate for rebuilding your L-48? Can you get it done for less than $2730?

 

Can you get the numbers off the pad at the front of the block?

 

that engine would be a nice 350 hp engine,it has hyd lifters wont need adjusted.would be nice in your vette,and run on pump gas

It should fit under the stock hood,but that intake is kinda taller than stock.

if you did all that to your engine you are looking at 3g to rebuild.

so its a good buy

 

Someone that has a 72 Lt1 vette that would like to have
at least a numbers matching block to make there car more valuable
will pay good money to get it, if it is a 72 LT1 block buy it and list
it for sale in hemmings.

 

Thanks for your comments so far,

Easy Mike said:
Do you have an estimate for rebuilding your L-48? Can you get it done for less than $2730?

No I have'nt had an estimate to rebuild mine yet, this motor is being offered to me before I have realy had a chance to think about what to do with mine.
You know how it is sometimes, things just come along and you have to make a descision fairly quickly before someone else snaps up what could be a bargain.

DWncchs said:
Can you get the numbers off the pad at the front of the block?

I may be able to see the bloke again to get the numbers off the engine Ill let you know asap.

Im not sure if it makes any difference but I am in the UK if you hadn't of guessed, from what I can gather I think it is good value for money over here, Im not sure how the prices differ to the USA. I also have no idea what a compression ratio of 9.35-1 means or if these figures are good or bad?

 

Hey Jerry,

No way your gonna get a new or rebuilt motor like that for £1500 here in the UK. go for it!

Hell if you dont want it, PM the guys e mail addy so I can talk. Good luck..


Just re-read post....


Heads have been ported and have standard valves So are they standard heads? if you were going to rebuild an engine, heads are one of the first things to replace.

Lots of pretty stuff there but not much in the way of internal specs. Got to be better than your smoking L-48. Contact some of the UK engine builders for advice. Did you get to the UK nationals? There was a builder there who gave a few talks. Will dig out his card for you.

 

If it's a good builder its a good UK deal, if he is a scoundrel, your in trouble. Sounds like a deal though and "should" fit right in. What tranny are you running?

 

Hi.
DWncchs Said:
Can you get the numbers off the pad at the front of the block?

The only numbers that I could find were:
GM 3970010 (on the engine nearest the gear box)
and RMW 0072 (on the engine at the front).

Jotto said:
Heads have been ported and have standard valves So are they standard heads? if you were going to rebuild an engine, heads are one of the first things to replace.

I spoke to the guy about the heads and he said he was going to put this engine in a landrover, the heads were already ported and he figured that the motor had enough HP for his needs, so he kept the ported heads on the motor.
But it does come with a pair of unported big valve heads
No I didn't get to the nationals I was on holiday perhaps next year

73-84 IMSA Said:
If it's a good builder its a good UK deal, if he is a scoundrel, your in trouble. Sounds like a deal though and "should" fit right in. What tranny are you running?

The guy is fine and trustworthy he had Real Steel advise him on this engine before he rebuilt it,he rebuilds all sorts of engines and he has a few tanks too.

As for the gear box,
I have a manual 4speed box at the moment, but couldn't tell you any more, because I don't know where to look for the gearbox numbers.

jerry

 

RMW is not an LT1 suffix in my book-maybe an over the counter block? Have you checked crate motor prices?

 

No I haven't checked crate motor prices, but to be honest the numbers are really difficult to read, I'm not sure if it is RMW! It has an R at the front but the MW is very faint, he said it definatly was an LT1 motor, the last car it was in was an Ultima race car, and was reported to be vary fast that was before the latest rebuild where the whole bottom was rebuilt ie~: crank etc

 

I think for some LT1 can be a loose term like L88.In this case if you trust his abilitys then buy it.With the crate you get a pretty good warranty I understand and documented performance.

 

Thanks for all you help and advice.

I think I will go ahead and buy it, perhaps use it for a while, then get my engine matching numbers motor rebuilt at a later date.