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post #1 of (permalink) Old 10-13-2000, 10:05 PM Thread Starter
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TR, MSD used with a 2.5L TBI engine ?

I realize you have answered almost every question in the world,, universe, on this subject. But I dont recall much info on the 2.5.
I am currently running a 1990 2.5L throttle body injected from a YJ, with a 5 speed. Absolutely no other mods other than a K&N filter and a high flow exhaust(no headers), new 8mm plug wires, and cap and rotor and Bosch platinum plugs. I dont want to spend a bunch of cash on this engine, because Ill be swapping in the mustang 5.0 mill in the next few months. I wouldnt mind installing an MSD6 off road ignition though, since I could retain it anyway when I swap.
My question is what would I need to swap to get any noticeable performance in the little 4 banger. the engine has about 65K miles on it and runs just great. It has good low end off road torque, but a little more highway power would be a big plus.
Id sure appreciate your input on this.

89 Wrangler
I take my Jeep "On the Rocks",usually "With a Splash of Addrenalin"
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post #2 of (permalink) Old 10-13-2000, 10:28 PM
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Re: TR, MSD used with a 2.5L TBI engine ?

You just described what a MSD will do for you with the little engine.
It will not add noticeable horsepower, but it will add a little torque, and lugging capacity.
It will help on you highway power, and it will add fuel milage if you take advantage of adding some timing.

All of the MSD Off road stuff with adapt right to your new engine.
That's the beauty of the universal MSD 6 module, it's almost universal!!
And it's the only case of one size fits all that it actually almost does...
(won't work on multiple coil distributor less ignitions)

I'm a big fan of the little four banger!
You would not believe what I saw done to them, and they are like Timex, Takes a licking and keeps on ticking.

Just like anything else, the little 4 will benefit from good plug wires, cap, rotor, and a good ignition coil.
You can leave the ignition coil out if you use the MSD module, it will more than get enough performance out of your stock coil...
You will need a good cap and rotor though....

After you install a good cap and rotor, and the MSD module, try bumping up the timing a little... The more you get away with, (without detonation) the more power and fuel milage you will get.
Cap and rotor will keep your cost down too.

Good luck, and let me know how the MSD module affects the little 4!

"I Have The Body Of A God... Buddha"
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post #3 of (permalink) Old 10-13-2000, 10:54 PM Thread Starter
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Re: TR, MSD used with a 2.5L TBI engine ?

Thanks much,
I gonna look for the Off Road version of the MSD6 tomorrow.
I will also install the MSD anti vibration coil, as long as it is interchangeable when I do the engine swap.
What is a good brand of Rotor and Cap? I have a 3 months old Bosch on it now.
What brand and type of wires and plugs?
You are right on about the 4 banger, it has been a superb little mill all summer long. It runs upside down, maintanes good oil pressure, never gets hot, and is not even the slightest bit tempermental. It only lacks when pulling a grade on the highway.
Thanks for your time,

89 Wrangler
I take my Jeep "On the Rocks",usually "With a Splash of Addrenalin"
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post #4 of (permalink) Old 10-14-2000, 10:29 AM
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Re: TR, MSD used with a 2.5L TBI engine ?

I'll give you a tip about the 'Blaster' and 'HVC' and 'Anti vibration' coils....
A stock type E-core coil is just as good as any of them, available at any parts store if your's fails, and is reasonably priced.
The total energy difference is about 2% or less.

It's the CDI ignition module that makes the difference. Use the MSD module, and suddenly your stock coil is a fire breathing dragon!!
Your stock module throws 12 volts or less at your coil.
The MSD module throws 400 to 600 volts at your coil, and suddenly your coil output isn't limited by INPUT anymore...

Why do you think I preach only using 1.35 ohm resistors, to keep the current to the coil up....
Instead of like some stock ignitions, using 6 to 30 ohms...
Coil input voltages down to 3 or 4 volts, you just aren't going to get any kind of spark energy out the other side...

Throw 400 volts at the same coil, and watch it come alive!! (Don't get grounded! The plug wires will knock you off your feet!)

The stock factory GM HEI remote E-core coil is almost identical to the Ford E-core coil, and both are good choices.
If I were you, I'd just use my stock GM coil until I switched engines, then I'd get a good Ford style E-core coil.
They are epoxy filled, so they are 'Vibration' proof if you mount them solid so they don't get smacked around when you are doing hard moves.

If you want some little rubber isolator feet, walk into any Harley shop, and ask for vibration mounts.
Get the kind with the wire inside, so when the separate, they don't throw what ever into the dust...
About $3 each, and have a 1/4" stud coming out of both sides of a rubber cylinder about 3/4" in diameter.
Good mounts of stuff like relays, horns, ect....

MSD sells them on 4 pack cards, with different size studs...
Small stud, about #10 screw, 4 pack, P/N 8823
Large stud, about 1/4" bolt, 4 pack, P/N 8800

I always bolt coils as solid as I can. (Angle iron is my friend...)

Any of the premium brands of cap and rotor should do.
Just make sure it has brass terminals instead of aluminum, or brass plated aluminum. (Yes, they are getting sneaky...)

If I didn't want to spend the $50 to $80 for a good set of 8.5 MM MSD wires, I'd go for a set of AutoLite.
They are as good as anything for cheapies, and you will know someone that will want them when you are done with them...
As far a cheap wires goes, AutoLite seem to be consistently the same....
Other store brands seem to variate wildly...


As for plugs, I use mostly AutoLite.
I can also recommend NKG and Nippon-Denso (Made in the same factory)
Don't pay more than a $1.25 for a plug, just no sense in it...

Every engine will run different with different brands of plugs.
I just find consistency with AutoLite, NKG, and N-D...

We have done nothing more than changed plugs before on the dyno, and gained or lost as much as 20 horsepower, but more importantly, as much as 3% of the torque curve...
And get it right back when we changed back to the original plugs...
And some times it's AC plugs, Sometimes it's Bosch, but we mostly get best results with AutoLite.
And AutoLite are US Made....
Go figure!!

Good luck, and let me know how it turns out....

"I Have The Body Of A God... Buddha"
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post #5 of (permalink) Old 10-14-2000, 12:52 PM
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Re: TR, MSD used with a 2.5L TBI engine ?

What about using a V-8s distributor with every other terminal ground off to double the coil saturation time between fires? Or is this a moot point with the MSD module?

I'm looking at an MJ with a blown 2.5, but I can get an MPI 2.5 pretty easily around here...

Restoring a '74 DJ-5C [img]/wwwthreads_images/icons/cool.gif[/img] It was running good, so I messed with the carb to make it run better. Now it wont run at all! [img]/wwwthreads_images/icons/mad.gif[/img]
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post #6 of (permalink) Old 10-16-2000, 12:25 AM
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Re: TR, MSD used with a 2.5L TBI engine ?

Grinding the terminals off won't do anything except make every other coil discharge go to the moon, and find a ground, (probably through the module or advance weights in an HEI).
You will have to change reluctors, and reluctor rings on the pickup part of the distributor.
I guess you could grind off every other one, and only use every other spark plug tower, but that seems a little dramatic for his intended purpose...

(We did make distributors for VW's years back by doing that very thing, but we used the small ford distributor, better cap and rotor arrangement...)

Coil Saturation!,.... Saturation!?...........We don't need no stinking Saturation!!
We have MSD!!!!

If the MSD module can fire the coil to make one continuous arc for 20 crankshaft degrees, and have 40,000 volts going to the plug the entire time, do you really think that there is a coil saturation problem?

We aren't talking about a GM HEI here anymore... This is the real deal!! That off road module is a bruiser of the worst kind when it comes to spark energy!!
It's a bruiser, but more importantly, it's YOUR bruiser!!

Besides, if you want terminal spacing and no coil in the cap for any GM I-4 or I-6, it's as easy as getting the correct cap and rotor.
All the internal parts are the same, you just change over to the remote coil version of cap and rotor.
Or didn't you all know GM made at least 6 versions of the GM HEI with a remote coil??
The distributor housings are the same, so everything else interchanges, all you have to do is change the coil plug for the GM version of the E-core coil (sound familiar), but the GM HEI guys are way too thick headed to get a clue...

If he bought a new Ford style E-core coil, he could use it with the MSD unit, because the MSD doesn't care, and the coil isn't hooked to the GM module anymore, so it can really work for a change.

There are lots away around, and ways to fix a GM HEI, but the Ford/Motorcraft distributor is still better than the HEI distributor, but if you use an older or late model GM distributor, and an MSD module, you have beat the need for doing anything to the distributor....

If he wants to update his GM, I'll help him there, but for now, he should stick with what he's got.

If he sends me close up pictures of his distributor and cap, and the module, I could make more suggestions, but for now, this will do...

Even GM thought the coil in the cap was a bad idea for at least 6 different models, and finally abandoned the idea all together....

"I Have The Body Of A God... Buddha"
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