Ignition/Carb/Intake Upgrades

will the DUI work with the MSD? and do I need to change over the gear... being that there will be a new cam/pump (melling) in place, I wouldn't think you would want to run an old gear with a new cam/pump...

im going to try to narrow it down and i'll post what I am leaning toward for further input/advice

thanks everyone!

 

will the DUI dizzy work with the MSD module?

and do I need to change over the gear... being that there will be a new cam/pump (melling) in place, I wouldn't think you would want to run an old gear with a new cam/pump...

im going to try to narrow it down and i'll post what I am leaning toward for further input/advice

 

Yes, it would, but it and the GM HEI distributor already have a module inside the distributor. "Unified Ignition."

You need to do some research about this ... if you had read the web page for DUI, you would have known this. http://performancedistributors.com/product/amc-dui-distributors/

Typically you keep the used distributor gear with the used cam gear. You can buy quality new gears (ie MSD) or trust that the gear that comes with your distributor will work with your existing cam gear.

 

thanks timgr... was planning on doing some reading tonite after supper...

 

For a little fun, go here... http://www.junkyardgenius.com/ignition/ign01.html and spend some time reading. However, read it with a grain of salt. Some think he is...well, genius and some think he is somewhat kooky. I've read his stuff and some of it makes sense.

Personally, Motorcraft distributor with MSD box and TFI upgrade. I kinda cherry picked based on what I learned here and other places. But the link is a good place to start.

Oh, and carb and intake? It really depends on what you want to do with the jeep. A rock crawler is different than a sand runner. You also need to think about the cam. The motor really needs to be thought of as a system and all the components of that system must work together for the motor to be what you want it to be. When you upgrade the electrical system, all motors benefit. When you start with the intake system, it gets complicated. I built my motor for low end torque because that is what I wanted the jeep to be strong in.

Same answer for the gearing. Mostly highway/on road use might be geared differently than a mud runner.

What is the CFM of the carb you have? Too many people think a bigger carb is always good but not always. You can over carb an engine. What you have might be just right. I like a duel plane intake because it keeps the air/fuel moving at lower RPM's and helps with lower end.

Have you thought about an exhaust? For most people the stock flows fairly good. Again, many people think just tossing on headders is a good thing. Yes and no, depending on what you do to the intake. You don't want a torque set up on the intake and a high HP set up on the exhaust. Look at Doug Thorleys. They seem to be very good.

I spent many hours researching and taking to manufactures and motor builders before I finally settled on what parts to use.

Listen to Tim and other here. IFSJA.org is also a good place to do some motor research.

Sorry but there is no real easy answer for this question.

 

thanks aallison!

the engine is coming back 'stock' aside from the boring it will receive to round out the cylinders... I don't even know what the CID will be when it comes back... no matter, really I guess

I don't know what the CFM is of the carb I have... all I know is that its a Holley... the exhaust was stock as well... manifolds to duals out the rear corners

I understand the set-up needs to work as a system, and this will be mostly a DD with an occasional off road junket (if I ever get it back on the road)... no drag racing for me... i'll pay to see that =)

I understand how the components work AS a system.. I'm just ignorant as to what individual piece works with what other individual piece... brand to brand etc

i'll leave the intake for now, and put the same carb back on as it ran great before the rebuild... so I guess that's as good a starting point as any... change too many variables, and you'll never know what works or doesn't...

as for the ignition, i'll go DUI first (per timgrs info/expertise) and see how that works... I still have the manifolds and MAY put those back on... if not, I will go to headers and shorties

I am at a point now where I have to RE-shop for a frame... the one I have wont marry to the tub... not biggie really, other than the PITA of shopping and begging for one somewhere...so the engine will sit for a bit, shrink-wrapped and i'll roll it over a couple times a month until I can install it

thanks so much everyone for your insight

 

Regarding "Junkyard Genius" - he is a controversial figure. He's banned here and on IFSJA - his attitude did not fit with the moderator's idea of civil discourse.

He goes by the handle "Jeephammer" on JeepForum and maybe other places. He makes interesting posts there - check them out - http://www.jeepforum.com/forum/f8/i-6-teamrush-upgrade-definitive-669495/ - check the bottom of his first post in the link for more links to his "how to" articles.

Lots of good ideas there. This guy is very opinionated, and thinks very highly of his personal opinion. Anyone who names their website "junkyard genius" has to have a very secure ego ... realize that he is a non-stop cheerleader for the "Team Rush" upgrade, which he claims he invented. This upgrade is known by various names, such as "Juicebox" and "TFI". I'm sure you've seen many references if you've read a little. I recall he is also an ex-employee of MSD, or had some kind of business or racing relationship with MSD, and he really likes MSD products. Not dissing the MSD stuff, but he may be less than objective when it comes to the MSD products. Personally, I suspect that the MSD stuff is seldom the best bang for your buck, if that's important to you.

 

Hey, no personal experience with the DUI stuff. You brought it up - I said owners seemed happy with it.

I chose the Duraspark distributor with big cap and wires for my CJ-6, with a fender-mounted HEI module and Pertronix coil. I probably would try something else if I did it again.

Re your frame, the '75 rear axle will have to have new spring pads welded on to work with the '76 or up frame. Making a '75-76 hybrid seems like a recipe for expense and frustration. So much changed for the 1976 model year ... You may as well look for a nice '76-up Jeep as a starting point. Many fewer headaches involved.

 

Tim, that might be the nicest, and most honest, assessment of him I've ever read.

IN my research, the DUI is a good product. People like it. But it also seems you can get just as good an ignition using the stock motorcraft carb and the upgrades as Tim suggested for a lot less money. I am using an MSD box because I picked it up, along with some other electronic stuff, for less than $100.

I also think you are smart going back close to stock and then working on each part from there. Knowing the motor is stock, with a stock cam, you can find the cam numbers and look for an intake that will take advantage of those numbers and a carb that fits that power curve. Might look at a duel plane intake and a smallish carb. Find the numbers on the carb and find out what CFM it is and go from there.

 

timgr-

no testimonial inferred, and my apologies if it sounded that way... i meant the info that you told me about and the reading that i did, helped me to decide on the HEI style/type system...the man doing the re-build ALSO suggested an HEI system... again no brand names were mentioned in either case, and i apologize again if i made it sound as someone was touting a specific brand vs a style system...

also, i AM keeping the 76 tub that i have... theres a lot of time invested in it vs just a little time invested in the frame... and i have moved the spring perches once already (to fit the 75 dimensions) once already... so i have that experience

the search for a 76-79 frame is now underway, and until i can find one thats worth using, i'll continue to do body work and tweaking...

again, i can not begin to thank everyone on here enough for their knowledge and time... as usual, its value is priceless

mk