Mopar MPI Question

jsharifi · #1 (**permalink**) 07-20-2003, 08:00 PM

Who's junked the Carter BBD and put the Mopar MPI kit on? I'm starting to consider making this upgrade, and I'd like to hear what people who've done it have to say.

Jim[addsig]

Beefy85CJ7 · #2 (**permalink**) 07-20-2003, 08:00 PM

Sorry...never done it...too much cash for my wallet...i'd go weber before MPI...i just like the good old carbed throttle response i get...better on the trail i feel. Good luck!
[addsig]

jsharifi · #3 (**permalink**) 07-20-2003, 08:00 PM

Yeah, I would consider that if I could, but the weber won't get past emissions here in VA. [addsig]

Jeff_C · #4 (**permalink**) 07-20-2003, 08:00 PM

I installed the mopar MPFI system on my 1990 YJ. It was easy to install and I dont stall out on the steep hills any longer. The HP gain Im not sure about because I installed a 4 inch lift and 33in tires at the same time. The MPFI is a lot of money. Ive heard from others that installed the throttle body injection and they like it also. A couple months later I regeared the diffs to 4:11 and that made a very noticable change. I can use overdrive on the freeway and pick up speed on the hills a little.[addsig]

jsharifi · #5 (**permalink**) 07-20-2003, 08:00 PM

That's good to hear Jeff... I've read on some other boards that some people experience 'pinging' after installing MPI, especially if you arent running premium gas... what's your take on that?[addsig]

Jeff_C · #6 (**permalink**) 07-20-2003, 08:00 PM

Ive never had problems with pinging. I first used this MPFI on my stock 4.2L and no problem. I have since rebult the engine and put the 4.0L head and had the engine bored .030 over and still havent had any pinging. I use 87 octane. I know others have reported pinging but I guess I got lucky with this change.[addsig]

jprtroy · #7 (**permalink**) 07-20-2003, 08:00 PM

I did it, the best addition I've done to my motor! I had the motor rebuilt, and then added the MPI kit fresh. You won't be dissapointed! I posted a few pictures on my jeeps.com web site. www.jprtroy.jeepz.com hopefully that'll work. When my install was finished, I noticed that the throttle return spring was real soft, I had to add a stiffer rate spring to the return. Othedr than that, the kit has been flawless!
You may run into issues trying to reuse the stock exhaust manifold I had already purchased a Borla header to install, because I knew I wasn't going to reuse the stock manifold. The problem will arrise when you try to seperate the intake and exhaust from each other.
As far as doing the work your self, the instructions are good. I've done all the work on my jeep since the 80's so installing it myself was no problem. If you are comfortable working on you jeep, you will be able to install this kit.
No more hesitation, no "poping" no more stalling on long hill climbs, should you stall in a rock garden, it will start (big plus) It'll even run on it's side (personal experience)
The kit does NOT come with a harmonic balancer. You have to get it seperatly. Your application may not require you to change it though (mine did)
I've tried the "throttle body" style fuel injection, it worked, (only cuz the mopar kit wasn't available yet!) but it can't compare to the Multi-Port Fuel injection!
(think I like mine?)
I tell you, my motor is as responsive as a freakin "pocket rocket" motorcycle engin now!
:-D And it looks cool under the hood too!

edited by: jprtroy, Apr 10, 2003 - 09:10 AM[addsig]

jsharifi · #8 (**permalink**) 07-20-2003, 08:00 PM

Great to hear troy.... are you still using the 4.2L head? You guys are reinforcing my desire to do this... It is a lot of money, but I know that I will not be selling my Jeep anytime soon (or ever), so it seems like its worth it for the added power and reliability.

jim[addsig]

jprtroy · #9 (**permalink**) 07-20-2003, 08:00 PM

Yes, still using the stock 4.2 head.
[addsig]

Snitty · #10 (**permalink**) 07-20-2003, 08:00 PM

I've heard much on the 4.0 head install... if you install the 4.0 head, that can be easily obtainable from a wreck... if you do that, you can use the 4.0 FI... you'll probably need the entire fuel system from it, computer, and a crank position sensor.. but i think it will give a better increase in power due to the head design.. i also think it would be cheaper[addsig]