im putting the whole l92 engine

 

I was looking into this and found that Mast Motorsports actually makes a small bore LS3 head 3.900-3.930 Part# 510-201. I got this off my email since they keep sending me specials and offers.

 

L92s on a 5.3

 

do not put l92s on a 5.3. the valves are not only bigger but the intake valve is spaced over. you can not notch the bores for clearance. even if you could get them to bolt on without snapping the intake valve the first time you crank it, it would be severely shrouded and wouldnt flow any better than stock heads. either get ported ls2/ls6 heads or just get a 6l block for the l92 heads.

 

I was just looking at those yesterday. The port size doesn't bother me at all, hell I've put 225's on a 5.3L once. I think the valve size is too big for a stock bore 5.3L, but a bored out block would make for a real rpm machine. The just might clear the bore on a stock bore looking at the valve size, but the shrouding would be terrible.

 

I havnt read all the posts here so I imagine it was already said, but I feel that the intake runners would be way to big for a 5.3. You would loose the torque needed in that small cubed motor. Also you need a different intake manifold.

 

L92 heads will NOT be worth the effort on a 5.3, period. No amount of experimentation will change this, and wasting time doing it would be foolish. Even if you did attempt it, the shrouding issues would negate any power gain, and the heads are just too big for that motor. 4.0" heads on a 3.8"-3.9" motor just doesnt make sense

 

sure they will work on a 5.3 ... 4" bore 3.2" stroke crank TADA!


alright whos going to be the first to say something about this

 

In that case yes a l92 COMPLETE engine will go in the place of the 5.3, NOT on.. You will need a few harnesses ect, but it will work.. You should have worded it diff in the beg..

 

I was actually contemplating doing this almost exactly. Take a 6.0 block and a set of LS2 pistons and balance them with a 4.8 crankshaft and rods, bushing the rod ends if needed for the floating wrist pin. Then take the L92 heads with a nice valve job on them and a custom spec cam, whip together and viola! Install 1900 TVS to flavor and increase low end torque!

At least that's the motor I'm dreaming up for my '06 GTO.