EFI parts
 

Hi

This question is for you guys who has done a CIS to EFI upgrade on the CIS intake manifold: What injectors are you using? - anyone experimented with injectors from other car makers?

Have you guys used other parts from other cars with succes in the CIS to EFI transformation?


I have a 1977 2,7 engine, a DC-20 cam and 10,1:1 JE. now going for a megasquirt setup based on a '78 CIS intake ...

Thanks from Søren

Soren,

It depends on a few different factors...

1. What does MS require? Low or high imp injectors?
2. What is your fueling requirements? ( what size cc injectors are you needing)

In a short answer, yes... you can use injectors from other vehicle manufacturers, as long as they meet your ECU and fueling requirements. You will just have to do a little research.

One question for you. How do EFI injectors fit in the intake where the CIS injectors used to be? Coming from the 930 world, I know that they have injector blocks that they buy that the newer, EFI injectors fit into...

And kudos to you for jumping into the EFI world. You will LOVE IT!!!!

Hej Søren

Are you familiar with tbitz? It is somewhat dated now, but still a great almost plugandplay MS based efi system. There are loads of info on this forum, worth spending the time reading.

Good luck

a great starting point is the tbitz system. Thats what I did and would do it again

The CIS intake will be a bit of a choke point, not really known for good flow.
Look for something like 35lbs high impedance injectors. I think Ford red tops are about that.
You are looking for no more than a 80% duty cycle so if your max would be 40lbs than you would want at least a 50lbs injector. That's ballpark, and BTW you also don't want injectors off of a L-jet car.

Do a google search there's a couple of sites that have injector rates and info for different cars.

MS and most systems use high impedance injectors, but all can use low impedance with the correct resistor pack.
My VW bug (180hp T4 engine) uses Siemens Deca 55lbs low impedance injectors.

sdsefi.com has excelent FAQ and tech sections.

2.7 with mods would probably put you near 240-250 hp maximum so you would need ~270-280 cc injectors and that leaves you enough headroom so you won't exceed 90% duty cycle. Modern injectors can easily be ran up to 95% duty still having control over them, old fat ones need more.

I would definitely prefer newer style ones, much better control.

I about to do a MS system on my 3.0, but not using the CIS intake. I will be using MFI ITBs and intake. My heads have been drilled for MFI injectors, and using the Classic Autowerks adapters (our host sells) I will be using Siemens Deka high impedence injectors from a BMW 328i.

Thanks for all these excellent inputs. I am working on a shortlist of parts to get and with your inputs I have come a good way.
I think the best way to do this is to start with the basics and from there expand the setup. I'm sure you will agree with me that things to p cars quickly erodes a budget :-)
An ITB setup is preferred but I will start off with the CIS intake for now - to get things going and gather experience. What to choose... Mega squirt 1 or 2?