Jeep Cherokee Forum - A guide to Megasquirt on the 4.0

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- - A guide to Megasquirt on the 4.0 (https://www.cherokeeforum.com/f67/guide-megasquirt-4-0-a-254321/)

Quote:

Originally Posted by Root Moose (Post 3710530)

Are you able to share any info on how you did this?

I have just looked into these as well now that you pointed them out, works basically the same as Megasquirt although a lot cheaper to buy! Well over here in the UK

Quote:

Originally Posted by Petbeemer (Post 3710584)

I have just looked into these as well now that you pointed them out, works basically the same as Megasquirt although a lot cheaper to buy! Well over here in the UK

Are you talking about Speeduino?

I took the way the quoted message was written by @Cummins93 to mean something other than Speeduino used in a piggy back fashion.

AFAIK Speeduino can not be used as a piggy back controller. At least the bit of searching I did on the Speeduino forums brought me to that conclusion. Happy to be shown otherwise.

Quote:

Originally Posted by Root Moose (Post 3710652)

Well originally i was talking of the megasquirt write up that was very well written, however things have moved on now with MS and MS3 can run basically anything http://www.extraefi.co.uk/products/MS_All_products.html
however i have also looked into the Speeduino which has also moved on and can be made a total standalone, slightly cheaper https://speeduino.com/home/

Awesome info in this thread. Will be squirting my xj this spring. Nice work peeps! I did Put a Barry grant demon 4 barrel on an x j manifold with two barrels mechanically locked out. Made an adapter, mud runner power!
https://cimg3.ibsrv.net/gimg/www.che...4ef40b5c7a.jpg
750 ÷ 2 = 375cfm. Thats enuff flow, yes?!
https://cimg7.ibsrv.net/gimg/www.che...c849fc1661.jpg
Details of construction shot.

Quote:

Originally Posted by Root Moose (Post 3710530)

Are you able to share any info on how you did this?

I used the speeduino as a piggyback to control a seperate coil and the injectors using a patch in design. This created minimal harness modification with total control of fuel and spark. The factory ecu remains and controlled all supporting systems. I used to make kits but there was not enough interest.

Anthony deserves a huge amount of credit. If it werent for him id have passed right over the speeduino as an option.

Quote:

Originally Posted by ab8127542 (Post 3694127)

Old thread, but maybe someone knows. Anyone doing this is finding this thread right off the bat, so here it goes;

You mentioned step up resistors for the hall effect sensors, more info on this? Which ones?, specific info on voltage change requirements, part numbers, pictures, locations for wiring them in, etc. ANYTHING on this subject helps.

Also, you said:

MS3 works with both Renix and SBEC2/JTEC patterns, no modifications required. But below that, you had a picture and said:

My custom 36-1 crank trigger, used with MS3x
Well, if ms3 works with both patterns, why did you install a 36-1?

Confused :dunno:

Also you repeatedly mention cam sensors. Only 2000+ 4.0's have a cam sensor, in place of the distributor. to the best of my knowledge? My 96 and 98 do not have cam sensors. Do we need to add one? If so, will an OEM from 2000+ work?

On stock pre2000 setups, how does the jtec control advance and retard? How is this translated to control measures used by ms3?

I have many more Q's. I'll save them if I get a reply.

Excuse any ignorance. Thanks!

Pre coil pack XJ 4.0's with distributors do have cam position sensors, in the distributors.

The computer uses this info to sequencialy fire the fuel injectors.

Fantastic write-up: Clear, comprehensive and easy to understand! I'm in Australia (land of the no-manual-4.0-Cherokee) and doing the AX15 swap with a 5.0 stroker rebuild. Given that the auto PCM wont like the manual trans, I cant use it as-is. By the time I get the PCM modified and run a piggyback, I would have paid the same as an MS3 Pro anyway... so here I go. Your help here has just made the project so much less daunting. Thanks heaps!

I'm debating running a amp'ed version of microsquirt on my 99 as we speak and may do just as you guys are talking about with letting jtec run everything but ignition and fuel. Just haven't decided on my trigger yet. When I start this project I'll post it up so everyone can follow along. I need some extra umphh after putting 31" tires on mine with stock 3.55 gears it could use 10-14 pounds of boost to be a lil more peppy.