Austarion

Hi guys its time for a rebuild.
Engine was making 380rwhp at 14psi detuned due to a 25 compression difference on 3rd cylinder. But due to a solenoid failure she overboosted and now needs at least new bottom end.
Currently has 2.4, custom manifolds, custom plenum, rx7 injectors, huge front mount cooler, Gt30 turbo, custom cam, slight machined and match ported head. Near standard bottom end, pistions were machined and dished but these will need replacing

I'm in two minds rebuild the 2.4 with top quality pistons, crank work and more aggressive head flow machining with the aim of being ableto safely use upto say 22psi if desired.

Or do I use the 2.4 bottom end and go twin cam ???
This would mean far more work and new manifold all over again, it would the work and extra expense be worth it in the long run by having higher revs being able to be used etc.

What are all your thoughts guys ???

I'm thinking the Sohc but not sure on pistns that are available????

Are you building something for a daily driver or are you going racing with this engine?

Pretty much for circuit duties :D

I don't really have a lot of thoughts on this ~ must be from years of drug and alcohol abuse :D .

But personally I would stay with the single overhead cam and the reason I say that is because that's what I got and I am putting 30 PSI of boost through it and it is awesome. Well my gauge reads to 30 PSI. So far I have not been in a car that felt the same under acceleration. This is me driving on the road with stock suspension. Now I am using a stock clutch and pressure plate just to stop me from opening the exhaust as I have a "Varex" muffler on it and when I am under boost and open the muffler it feels like I have another turbo kicking in. The old 4 button clutch I was running was good for speed but lousy in traffic and especially lousy for speed traps. I have heard of a clutch that came out a few years ago that is a combination of button and standard clutch. I am using forged pistons and balanced crank in it with multi point injection. The head at the moment is using double valve springs which has stopped the valves bouncing.

Life is wonderful

I should have mentioned that my engine was build for 1/4 mile and I use it in a daily driver.

What head are you using? Personally I would stay SOHC 2.4L

I know of a certain engine (2L) making close to 400HP at the wheels with 600ft lbs ATW... :beer

Head is same as bottom end a 4g64, think it was origanally in an Express. Van.
Oh and for those wondering MPI system of course...lol

Other mods :
Coil overs
Front and rear strut braces
Lengthened lower control arms
AP racing brakes
Half cage
Thicker sway bars 21 and 24mm I think.
Adjustable strut tops

Ok... stay SOHC 2.4L. Let me know if you need pistons... I have a connection :beer

Very interested in that :D
Looking for a good set of forgies no matter what, I'm sure after 10 years of this set up mine are shot
Thanks !!!!!

I recall your build as one of my favourites, as I somehow always been a 2 valve man. I actually like its simplicity
I had just picked up a truck 2.4 with intention of boosting it, when you posted yours.
I seriously doubt you'd walk away disappointed if you fed a 2.4 sohc (with a good cam) what it wanted.
Must've felt great when she "overboosted" tho :D :D

Although I have lots of twincam bits, I've seen way too many insane performing 2 valve motors, to abandon the sohc

personally I would stay with the single overhead cam and the reason I say that is because that's what I got and I am putting 30 PSI of boost through it and it is awesome. Well my gauge reads to 30 PSI. So far I have not been in a car that felt the same under acceleration

SOHC revival! Following thread with interest :D

I would have still been SOHC if a certain dyno guru :glare: hadn't stuffed up a tune and cost me a 3k old stroker. :x