I think I finally made it?

[Strippperguy]

Soooo, it's been quite an adventure trying to get approved here.
I think I'm approved.
My needs right now are to get as much info and support as possible for my EFI conversion.
1997 Jeep CJ5 with an AMC 258.
I rebuilt my engine forever ago, bored .030 over, new pistons, ground crank .010 under, new bearings, Comp Cams 252H, Clifford intake, Hedman headers, all 2-1/4" exhaust with Flomaster series 40 muffler, HEI distibutor, electric fan and a Weber 38DGAS.

The engine runs well, but has a hard time starting after sitting for a few days.
I four wheel on big rocks sometimes, and the steeper angle stuff really messes up my Weber.

So I'm planning to switch to EFI, specifically, a GM TBI.
Since it took me so long to get approved here, I abandoned my original plan of sourcing all parts myself.
I just ordered a TBI kit from Affordable Fuel Injection folks, essentially all the same stuff that I planned to buy anyway.

More than likely, I'll need to alter the program that AFI supplies, since my engine deviates from stock.
Hopefully, I can learn enough from the gurus here so I can limp through this without too much suffering.

As for a further introduction, I am a cofounder of an extremely advanced R & D company, Mohawk Innovative Technology, Inc.
I initially served a 4 year apprenticeship as a toolmaker, and worked in research for over 40 years.
I'm a design engineer at MITI, with experience in high speed rotating equipment, rotordynamic analysis, machine design, static and dynamis vibration analysis, as well as all phases of data acquisition and data reduction.
I'm mostly retired now, and rebuild wrecked cars, motorcycles, and motorhomes for fun and profit.

Oh, and I build canoes, lots and lots of cedar strip canoes, hence the stripperguy name.
Thanks i advance for letting me pick your collective brains,
Mike T.

[dave w]

Likely the AFI TBI system uses 1227747 ECM.

Gearhead-EFI link for 1227747 information http://www.gearhead-efi.com/Fuel-Inj...Information-42

[Strippperguy]

dave,
Thanks for the link...yes, that's the same ECM that AFI uses.

Dunno if there's a minimum number of posts before I can post pics, but here goes.
Here's the aforementioned CJ5, I've had it since 1995, did all of the work myself.




And here's a pic of some of my canoes, all were built by me

[steveo]

don't miss the boat putting modern stuff on your ancient engine

it's a lot of tedious work doing any EFI conversion and TBI is pretty weak tech

i see you've bought some cool stuff that you want to keep but if you are into fabrication/engineering (which is a weak spot for me) i would be building a custom rail and putting injectors right in that clifford intake, and using sequential injection

although i guess your goals are in alignment with TBI if you just want the easy-ish road, a jeep with a tbi slapped on it isn't that special, something with a totally unique injection system is

[ralmo94]

Nice looking jeep, and nice canoe's.

While port would be an advancement, I see no real world advantage over TBI, as long as it suits your rpm and cfm requirements, but a modded Clifford intake would be pretty awesome. That's my $0.02.
Welcome to the forum.

[MO LS Noobie]

Them are sweet looking canoes. I wonder how they would hold the to the Ozarks Rivers? Regarding the Jeep, the TBI would definitely be easier and would get you about 80% of the advantages of a sequential port set up, especially the rough terrain and steep inclines. I had a 401 in my grand Wagoneer I converted to the old Holly DFI four barrel set up just because of that. Welcome to the forum, there are many people here for help and advice.

[Strippperguy]

Thank you all...
Yeah, I'm not looking for anything unique WRT fuel injection, just a more consistent output from my engine, especially off road and off camber.
My CJ weighs 2,200 lbs and has all the torque that I need. As it is, my CJ is extremely capable off road, and fun on road. I'm reluctant to build it into a trailer queen.
Maybe somewhere down the line I might modify my Clifford intake for multiport sequential, but for now, not really needed.

The canoes are much tougher than most people realize. I've beat the snot out of them for decades, they mostly survive pretty well. And if I do damage one? No big deal, I built them, I can surely fix them.

[1project2many]

Soooo, it's been quite an adventure trying to get approved here.
I think I'm approved.

Yes, you're approved. My apologies for the extended wait.

Oh, and I build canoes, lots and lots of cedar strip canoes, hence the stripperguy name.

As someone responsible for trying to prevent spammers who love posting bad links to illegal medications and other products, I'd like to tell you that including a note like that would have helped get your approval much faster. :-)


Your Jeep looks great. I want to recommend considering a tank designed for EFI or some other method to prevent fuel starvation as the jeep climbs, twists, and lurches through it's trips. The fuel bowl in a carburetor stores fuel, masking situations where there is temporary fuel starvation at the pickup tube. Once you go EFI you will notice every time this happens.

[Fast355]

Having worked on and driven both the OEM GM TBI and long runner MPFI 250 I6 engines, find a later MPFI intake for a 4.0L and swap to MPFI. The TBI is a good system, but it still has the same issues prevelant to a carburetor that are especially troublesome on the long I6 intake runners. The 2 center cylinders end up running rich and the 4 end cylinders end up running leaner. With an unheated air intake and unheated divoriced manifold the a/f split becomes even worse at idle and lower loads. The port fuel will run smoother, get better fuel mileage and have better driveability especially after a cold start. You can still go the GM management route to make things easier to tune using the later 4.0L MPFI manifold. I say later model 4.0L manifold because somewhere around 2000, Mopar redesigned that manifold to flow better to offset power loss from other changes to clean up emissions. The older 4.0L manifolds have a long straight plenum and straight runners, where the better manifold has long, curved sweeping runners that branch out from under the throttle body. I would use the 7730 ECM to control the system using a speed density 1990-1992 3.1L V6 Camaro or similar calibration. It would also be worthwhile to integrate GMs 7-pin EST module to the OE Mopar distributors pickup setup, delete and lock out the mechanical and vacuum advance mechanisms, and comperize the ignition timing. I have integrated that TBI/TPI style 7-pin module to both Mopar and Duraspark style distributors, ditching the failure prone control modules and vacuum/mechanical advance setups on both. Hardest part of that is setting up the latency table, but even that is straight forward using a timing light and fixed timing values of say 15-20* in the spark MAP. Fix the timing values to where they are all the same, then adjust the latency at various RPMs to make the ignition timing match the commanded value. End of the day, TBI is an improvement over a carb on an I6, but if I am already doing major surgery, I would want MPFI, especially since a low cost MPFI manifold, fueql rails, and throttle body already exist for that type of engine at just about any local wrecking yard

[Strippperguy]

Thank you, gentlemen, for your advice.
My CJ currently has a 2 year old gas tank, having worn through the OEM and a decade later, a replacement as well. Ground clearance and breakover angles are a constant concern for me, and a larger than 15 gallon tank would need an alternate skid pan, and likely reduce my clearance.
Even though costs are not a major issue, I don't like to intentionally obsolete components until they age a bit...
Soooo, the current tank will stick around for another decade or so.

As far as MPFI with an alternate head, same kinda story. I have a refreshed head, with maybe 20k miles on it, and a Clifford intake and Hedman headers, neither of which are compatible with a head from a 4.0.
I initially looked to find a Jeep with a 4.0 that I could cannibalize, but junkyards empty out quickly for Jeep parts, and Craigslist and/or Marketplace donors are generally overpriced or just plain junk.

So for now, at least, I'll dip my toe in this FI pool a little at a time. If I get comfortable enough, maybe Ill get a stand alone ECM that I can program, or maybe try to burn my own chips.
But for now, baby steps, and keep using as much of my current hardware as possible.

With all that said, I know you're all dying to know more about my CJ.
Yeah, it's a 1977, with a glass body and front clip, weighs 2,200 lbs.
I did a SOA (Spring Over Axle) swap using OEM springs from a Wrangler. 12 inches of travel at every wheel.
Front Dana30 and rear AMC20 axles are fully trussed, with alloy axle shafts and auto locking differentials front and rear.
I regeared the axles to 4.56:1, and regeared my swapped in Dana300 transfer case to 4:1 (OEM was 2.6:1) Also swapped in an overdrive 5 speed transmission. edit: forgot to mention I'm on 35" tires.
I also fabricated my own hi steer, using flat top Dana44 steering knuckles and custom fabbed (by me) steer arms, drag link, and tie rod, using 1 ton tie rod ends.
There's other boring stuff like a Tom Woods DC rear driveshaft, electric fan, hydraulic winch, etc.
For a 47 year old vehicle, that sees much abuse, it's holding up pretty well. It's extremely capable off road (nothing is unstoppable) and comfortable enough on road.

This next switch to EFI will likely be the last major modification, since I have almost everything else just the way I like.
Again, thanks for letting me into the club, and for all of the over my head knowledge you've shared.

[steveo]

it's a great jeep and you've done the right stuff to it

i've often thought of getting a CJ, but i keep holding off because i need a big jeep, i go deep into the bush with several dogs and lots of gear, and sometimes get too deep into things and have to sleep in it in the middle of nowhere

that is an insanely low final low gear for such a little jeep, way lower than even hardcore rock buggies out here use. you could pull a tree over with that thing

[1project2many]

It really sounds like you love your Jeep and it seems like an extremely capable rig. I have gifted a 95 square eye to my son and it appears we are building a street Jeep. A good Jeep build would be fun, but he's decided since this YJ has every option available from AMC it doesn't make sense to strip it.

AMC axles... one of my first jobs as a young mechanic was working in a shop that specialized in axles and manual transmissions. I was told to remove a wheel flange that had spun on the axle. Man, those guys really enjoyed watching FNG try to figure out how to do that. Boss saved me... lots of heat. We're installing new axles.

Even though costs are not a major issue, I don't like to intentionally obsolete components until they age a bit...
Soooo, the current tank will stick around for another decade or so.

Fair enough. I did not throw out the OE tank in my '57 pickup just because it was not designed with FI in mind. I modified it to accept an EFI pump that sits less than 1/2" off the bottom of the tank. But after spending 23 years having to add fuel whenever the fuel level dropped below 1/2 tank, I can say that some battles do not need to be fought. When the brass float failed due to E10 corrosion a few summers ago, I spent time designing and intalling a set of baffles that acts like a cup around the pump pickup to reduce fuel starvation. It's much better now.

Some of the '80s and '90s marine applications addressed this issue a little differently. These applications used the engine mechanical pump to fill a reservoir. The reservoir used a float to restrict fuel when full, and they contained an electric pump that circulated fuel to the engine. Any unused fuel was returned to the reservoir. I used one of these systems to convert a '67 Chevelle to EFI and it seemed to work well. I had concern the fuel in the reservoir might get too warm on long trips but it was good here in the northeast for trips up to 2.5 hours. This might do the same thing?
https://www.ebay.com/itm/166609517501

HTH.

[MO LS Noobie]

The remote reservoir works well, the only problem with it on jeeps is space. You are kind of limited in where it will fit. Edelbrock, Holly, and FiTech all make their own remote reservoir systems.

[Strippperguy]

Thanks again, guys.
I hadn't given serious consideration to fuel starvation...
When it comes time to retrofit the Walbro pump to my tank, I'll see what sort of baffle/pan I can fit through the tank opening. I have a full machine shop at my disposal, and I can fabricate just about anything.

I occasionally buy wrecked vehicles to rebuild and sell. I've done quite a few Jeep TJ's, had to drop a couple gas tanks to rework other stuff, even replaced a couple fuel pumps on TJ's, but I never peeked inside the tank!!
More knowledge is such a dangerous thing.

[Fast355]

Thanks again, guys.
I hadn't given serious consideration to fuel starvation...
When it comes time to retrofit the Walbro pump to my tank, I'll see what sort of baffle/pan I can fit through the tank opening. I have a full machine shop at my disposal, and I can fabricate just about anything.

I occasionally buy wrecked vehicles to rebuild and sell. I've done quite a few Jeep TJ's, had to drop a couple gas tanks to rework other stuff, even replaced a couple fuel pumps on TJ's, but I never peeked inside the tank!!
More knowledge is such a dangerous thing.

For retrofits, hard to dismiss Holleys excellent Hydramat product. Had I not looked at a Dorman tank that had a massive baffled area added to it for the G-vans, I would have used a Hydramat for it. Would have been cheaper than a new tank, but just barely, but the tanks for those vans are dirt cheap.

The hydramat material works like a sponge, holding fuel inside of it for the pump to pickup. I used it on a carbureted tank on an EFI conversion and it lets the engine run until the tank is bone dry. In some conversions where tanks are $$$ or not available with baffling, the hydramat is an excellent alternative to tank modifications. The one I used looked like a fuel sock with a 3/8 NPT fitting. 3/8 NPT to 3/8" hose barb and adapted to the 3/8" fuel tube with a piece of hose rated for immersion.

When the hydramat stops pulling fuel when it is sitting on the bottom of the tank, you are out of fuel.