Well contrary to what I understood, running a big open plenum manifold on a relatively low revving, heavy 4x4 with big wheels doesn't work that great. It's not a MegaSquirt issue, it's just the fact that big short runners don’t give you any low down torque - the Edelbrock Victor JNR manifold is designed for 2500rpm-6500rpm track use.

So there's two options; short-term I'm going to modify my original Edelbrock Performer RPM manifold for fuel injection (I.e. put bungs in it), then I will get together the parts to fit a Tuned Port Injection (TPI) manifold to it which is supposed to be a "torque monster".

Ive also ordered a Comp Cams 12-235 hydraulic cam, which should make better use of my heads and manifold combo (although the performer RPM isn't the ideal manifold for my app, i should just be running the performer manifold)

This is a output from Desktop dyno, comparing my current Cam (2101 edelbrock), A CC411 roller and a CC12-235 Hydraulic - even though the gains aren't massive, given that I'm stripping it down anyway, i thought i would upgrade it anyway.

I will be selling my Victor Jnr Manifold on ebay once ive replaced it, it cost me £200, plus the work to convert it to EFI. obviously if you have a heavy 4x4, don’t bother buying it!

The Job begins

So sadly, that lovely single plane manifold, that my dad spent considerable time modifying is now going to replaced with my original dual-plane manifold.

I ordered this cam from Jegs on a Sunday night, it turned up in the UK Wednesday morning - that's actually quicker than real-steel in the UK!!! (apart from the $70 shipping - ahem!)

Were now experts at doing manifold conversions, We transferred the spacing from my original fuel rail, with a bit of luck we wont need to modify it too much. - (do you think dad has got a thing about wearing blue sweatshirts?)

This took several days work on my dad's part. Due to the un-even height of the ports on the dual-plane design, its tricky to weld the bungs in.

Here's a picture of the re-assembled engine. I re-located the idle control valve, much neater now.

Update. Well i'm happy to report that the new (old!) manifold has returned the car to how i expected. Additionally i have fitted a GM HEI distributor, which i has made quite an improvement also. MegaSquirt seems happy with it, timing is nice and steady now. plus it has a vacuum advance, which has improved partial/mid throttle response.

I just completed the build of my Tech-edge Wide-band unit, got it working stand-alone on the car, Works pretty well. It took me about 8 hours to build the WB, Cable and LD01 display. I'm working on some new include files for MegaTune, that uses the WBlin output rather than Svout non-linear output.