I am looking for an L03 305 engine (in the UK). I have a 1986 camaro 305 with the LG4 engine. Is the LG4 block and heads similar or identical to the L03 block and heads?

 

The L03 heads have the 87-92 intake bolt pattern, older intakes can be made to fit by elongating a few bolt holes.

Since your car is an '86 it's block should already use the one piece rear main seal, like the L03. 85 back used the 2 piece seal.

L03 heads are what they call swirl port heads. These heads don't flow very well. Your LG4 heads are a modification that L03 guys actually do to their engines, since the LG4/L69/LB9 heads flow better than the L03's heads.

 

Andy,

Instead of an engine swap, you might want to consider a rework of your existing engine. I can't imagine the salvage yards in Britain are full of SBC engines.

Unless you engine has suffered a catastrophic failure, it may be more economical and more effective to build what you have into what you want. Your LG4 should have 9.5:1 compression, and slightly better heads than the L03. All you need to do is improve upon that.

 

Change your carb, dist, and intake manifold.
Here is my old setup and it made a huge difference on my 86 LG4 Trans Am,
Edelbrock 1406 Carb, Edelbrock 7101 Intake Manifold, and Vacuum Advanced Distributor, and an Open Element Air Cleaner



I've nearly completed my TPI swap, here is a pic,

 

Hey Zepher--I was curious as to where you grabbed that air intake from? The dual setup. Is that a stock setup from something? The more air the better!

 

I think SLP may make it, costs $225+ dollars.

 

That is one sweet piece! Wonder if something could be fabbed up--for financially challenged guys such as myself!

 

If you have a camaro with tpi using the stock intake and routing some drying hosing up from the fog lights would probably be just as good if not better. Otherwise a large PCV T could be used.

 

I've got a T/A. But I just noticed on Zepher's ride--he doesn't have a maf on there.

 

Ya, SLP sells it for the Speed Density 90-92 Fbodies. $299 on thier site a few weeks ago.

John Millican built a nice dual inlet for his LT1 intake on his 383.
Let me see if I can find a pic of his,

 

Zepher- thats a really nice setup with that 86 LG4 l've never seen such a clean spaghetti-less engine from that era. nice job- got any track times, or HP numbers?