killervette666

i just found out that my 79 vette has an L-48 and not an L-82... Im just wondering how much worse is it? i know that the L-82 had a forged crank and pistons, as well as 4 bolt maincaps, and that the L-48 had a cast crank and pistons and 2 bolt mains, is there anything else? :cry :banghead:

PROSOUTH

My '80 had an L-48 in it from the factory. What you have is a stock standard Chevrolet passenger engine. Nothing more and nothing less. It's a good passenger engine or base to start with.

It's a great block to start with. You can use splayed caps and convert it to a four bolt or use main studs and do just as well. Scat and several other companies have 383 stroker cranks and kits that are pretty reasonable. Heads are numerous and depend on the rpm range and piston/cam etc, used.

I pulled my L-48 out and set it in the corner, bought me a GM crate engine and a TKO 5 speed, I can always go back, to the L-48 or set it in something else. Jim

MotorHead

:iagree: Mine will smoke most cars on the road (at the track of couse ) :lol:

mrvette

For all the chatter/talk and figgers I thought my L48 was a decent engine, no super powerhouse, but moved my stock running gear '72 just fine with the original 4 speed stick...but it had been rebuild decently with mild cam by previous owner.....

NOW after establishing a base line of the performance....I added all sorts of upgraded by plans......the most important of which was the L98 TPI setup...
instant boost to about the rated 250 some odd HP...maybe even 300....

whole new level of performance, and just a good a runner as my '87 vette was....
better even.....

so IMO, nothing rong with an L48, good base to build on.....maybe a few steps up on the cam, then headers, and DPFI, any you get twice the fuel economy and a goodly power increase....

GENE

68350hp

The L-48 is a pretty good motor. The L-48 in my '74 was rated 195 hp from the factory. The only mods on that motor are advanced timing, K&N Air Filter, and the emissions system was removed. Even just with those little mods done to it, it has plenty of power. As the other guys said, it is a great base. Since it's a Chevy 350, there are a ton of performance parts out there for pretty reasonable prices.

AGVI

The L-48 Rules! I've been trying to blow mine up for the past 5 years....rev to 6500 rpm then shift.....it won't explode....damn it! :D

no_radio

I'm getting around 400HP from my carbureted L-48...but the only stock parts left are the block, crank, and connecting rods. but it is still a 2-bolt main, no studs or splayed patterns, although I wish I had, because I'm scared to go over 6500 RPM.
Jeff

joeveto

I have an L-48. I stripped it down and rebuilt it. Now, it's much, much better. Face it, back then, the L-48's and L-82's were both slugs. But they both have a lot of potential, as well. :yesnod:

Tom73

L82 had the 2.02/1.60 valve heads while the L48 had the 1.94/1.50 valve heads.

tom...

Stewart's74

Not to beat a dead horse, but.....
I too had a lowly L-48.
Here's what I did to make it more of a Vette motor.
Bored .030 over
New Hyperutectic (sp?) pistons boosted compression ratio to about 9.5:1
Performer Manifold
268H cam
Lars rebuilt Q-Jet and Lars re-curve kit.
Also, your tranny and rear gearing have a lot to do with the equation. If you have an auto, get a higher stall converter. I went with a 2500 for my TH400.
The TH400 sucks a lot of HP.
Moving to say, 3.70 gears will instantly give you more off the line.
Of course, a set of free flowing heads will also assist you in your quest for HP.


[Modified by Stewart's74, 9:44 AM 12/16/2003]

flood

My stock L-48 runs 15.8 at 5000 ft. thats roughly a 14.8-15.0 at sea level. I did put 3.70 gears in it and its a 4 speed.

Not bad for a 165hp motor pushing a heavy car. Its torque that does the job, I believe that its rated at around 250lb ft or so (stock).

Upgrades ensue. :cheers:

gliot1

about 30hp

no_radio

Yeah, but they are the exact same casting, so you can take your L48 heads to the machine shop, put some 2.02/1.60 valves in and you have L82 heads.
A little bowl blend while you're at it and you're L82 heads and then some...
Jeff

tippi58

My 77 was a California car so the owner couldnt get the L82 engine. he put on the L82 badges and valve covers. :rofl:

Lucky I checked the engine numbers first. :eek:

Mine is a cruiser and that suits me just fine. :steering:


:cool: :cool: :cool: