converting redblock kjet head to efi

Maximus

im wondering if anyone has experience with or knows if converting a kjet head to work with efi is possible, or difficult. I have a worked 405 head and want to run the car on haltech for a turbo build but i don't want to spend the same amount of money having a 531 head worked.

and if you've done it or know of someone who has done it, what is the process?

Spac

Maximus

You can leave the K-jet injectors in place and ignore them, you can plug the holes with welsh plugs, or you can make up aluminium plugs to block the holes.

I can’t remember what happens with the EFI coolant sensor, but I think the worst case scenario is that you can unscrew the K-jet sensor and replace it with an LH-jet one.

Ramrod has mentioned the extra ports for pollution gear on the exhaust.

Everything else bolts up.

Major Ledfoot

Maximus

The process .....

plug the Pulsair holes in the head
plug the K-jet injector holes in the head
get a Dave Barton harness
LH 2.4 B230F inlet manifold and fuel rail will work, you'll need a fuel pressure reg to suit the application
add correct sensors to the 405 for knock and coolant temp
change the main fuel pump so it's a 3 Bar system not a 5 Bar one
etc

I'm putting an LH 2.4 B230 engine in The GoaT, which was originally K-Jet, thus am a bit familiar with what's needed and involved. I have to do this, since The GoaT's engine threw a rod and I didn't want to stuff around with K-Jet. Had the original engine not borked itself violently, and as a firm believer in the saying If it isn't broke, it doesn't need fixing, I would not have bothered.

ramrod

Good evening

The only difference between the early and late model heads is the pulseair holes (which I block with threaded plugs) and the fuel injector holes (which I guess the same can be done)

That and the size of the coolant passageways but that’s not a major difference (I think if I’m not mistaken the later heads used the small passageways) and are stronger castings

Maximus

Brilliant.

Looks like I’ll be converting my 405 head to efi 🙂

volvodriverman

https://www.stsmachininginc.com/products/k-jet-injector-plugs-for-240-turbo-non-turbo-models

This is a neat solution to the injector holes.