Dual throttle bodies for a 2.5??

[81Chero]

I've been messing with motors for a few decades and with each engine/make that I get, I can't help but think of making it the way I WANT.

 

Now that I got this Comanche, and found a core motor to build up, I thought of modding the intake for two throttle body assemblies. 

OR, if I do MPFI, then two horizontal throttle bodies like dual side draft carbs using 3.5L t/b's

 

So, getting back to the stock version. Can this be done that say I made the intake would have dual stock t/b's, and just splice/split in the wires to run two..?

And yes, do the vacuum lines also.

 

Thoughts and Ideas..

 

E

 

 

 

[Guest]

I'm not sure how feasible that would be; not just to get the plumbing for them both right, but the vacuum wiring as well. Let's not even talk about space clearances.

 

Not to mention, I doubt that if you go with the Renix CM (computer module), that it could be tinkered with to accept that much input and information being thrown at it from 2 seperate throttle bodies. Perhaps the Chrysler MPFI CM might be able to, but I very much so doubt it. The sheer amount of on-the-fly variations of air being taken in to fuel being sent into the port (or ports, if you're taking a MPFI 2.5 into account) would be nigh impossible for the 20+ year old electronics to handle. Especially so with a single fuel injector on the TBI units.

 

Given how many times it has to pulse in a span of, let's say, 10 seconds... unless you could find a way to somehow modify the computer in some way to limit the amount of injector pulses between the two, that would be the only way I could see you  getting an appropriate amount of fuel delivery to combine with the air coming into the intake manifold.

 

Irregardless of all this, it would be interesting to see if this could be done. I know I would personally love to see if it.

[yxmj]

Your second plan might be more feasible.....if you had MPFI the the side draft would be more of an aesthetic piece.....it would obviously allow more air flow as well.....I would only hook up one side with TPS... :dunno:

[Jeep Driver]

The short answer is, no.

 

 

ECU that runs a single injector will not run dual injectors. Renix ECU cannot be remapped.

 

Otherwise you could simply use a Clifford intake and a two barrel TBI off a SBC.....you cannot.

 

 

 

 

You could spend about $800-$1000 on a pair of Webers. Have some machine shop custom mill you a pair of billet long runner intakes...that might run you about $2000. Pay a specialty shop to sync them.....another $300

Go find a mechanical distributor out of an old 258 and see if you can cobble up something with a points ignition or you'll have to go aftermarket all together and I have no idea who makes a stand alone aftermarket ignition system for the 2.5. 

 

After you spend $3-4K.........let us know how it works out.

[Jeep Driver]

http://www.4wdmechanix.com/Tuning-and-Troubleshooting-the-2.5L-Jeep-TBI-Four.html

 

Something you might want to look at.

[Jeep Driver]

AMC/JEEP              2.5L 4 CYLINDER             47-0025       CAST      DISHED              264H, 272H $799.00

 

 

 

 

 

Above is the only listing Clifford shows for the 2.5, they are not making the intake anymore.

 

http://www.cliffordperformance.net/index.html

[Eagle]

Your second plan might be more feasible.....if you had MPFI the the side draft would be more of an aesthetic piece.....it would obviously allow more air flow as well.....I would only hook up one side with TPS... :dunno:

^^^ This.

 

I can't imagine how you could convert a throttle body injected 4-cylinder to dual throttle bodies. If you run one injector, it might run too lean with the extra air, and if you run two it much not be able to shut down the fuel flow enough. With a multi-port injection, the injectors are totally independent of the throttle body, so no rewiring would be necessary.

[Eagle]

Otherwise you could simply use a Clifford intake and a two barrel TBI off a SBC.....you cannot.

Does Clifford offer a manifold for the 2.5L? I thought of them, too, but I was just on Clifford's web site and the only parts I saw for the 2.5L were camshaft kits. Did I overlook something I should know about?

[benjy_26]

It can be done with Megasquirt...but why? Just go MPFI.

[Jeep Driver]

 

Otherwise you could simply use a Clifford intake and a two barrel TBI off a SBC.....you cannot.

Does Clifford offer a manifold for the 2.5L? I thought of them, too, but I was just on Clifford's web site and the only parts I saw for the 2.5L were camshaft kits. Did I overlook something I should know about?

 

They used to offer the carb intake and headers.......no longer.

[Jeep Driver]

http://www.wranglerforum.com/f135/high-performance-aluminum-intake-manifold-for-carbureted-2-5-a-185423.html

 

 

There is an old ad, someone was selling a used Clifford intake.

[benjy_26]

In the 4AGE world, individual throttle bodies were the hot thing about ten years ago. They look cool and sound fantastic when revving up past 7k, but all the serious racers noticed that you weren't making any more power than you would with a well tuned MPFI set up.

[81Chero]

It was just a though..  I've been messing with OBD-0 and OBD-1 hondas for a long time and it wasn't too hard to bolt on a larger throttle body, convert to a 4-wire O2 sensor and maybe larger injectors, 

BUT it made a very noticeable difference in response and low end torque. Probably a 50% gain in the output in those early engines. Stock was 113 and with a header and those mods one was up to about 150- and up with high comp pistons. (same engine mods but custom tuning like Chrome and turbo edit are more than doubling those figures)

A side lined project of mine is to install a LT1 Chevy in a 98 BMW 328i vert, and wanted to install 3 Chrysler 3.5 t/b's on the top of the manifold and do away with the EGR and IAC and run it as speed density.

I've talked with a couple LT1 tuners and they said that it could be done ($$$) and i've already got a stand alone harness.   My inspiration came from this vid and thought WHY NOT.. 

 He made his own intake from those above mentioned t/b's 

 

And YES, I know that it wouldn't be worth it for some, and there would only be minimal results in HP or torque,   BUT, I'm still looking for a good used tig welder and just happen to find a '01 Dakota (with an absolute HORRIBLE paint job) at a pull-it this evening.. To which I'll be asking another couple of questions started in another thread.

And yes, I doo understand that it's a different operating system also.

From what I've read, it seems like the OBD-2 might lend itself to 'tweeking' of the ECU. (I wonder if most of the operating harness is in the engine compartment)

 

It's more of a challenge to me.

 

Errol

[Guest]

I've talked with a couple LT1 tuners and they said that it could be done ($$$) and i've already got a stand alone harness.  My inspiration came from this vid and thought WHY NOT..

 

It's more of a challenge to me.

 

Errol

The greatest inventions were sometimes made by people who thought "Why not?". I wish there were more people with this attitude nowadays; and this is coming from a 22 year old. If it interests you, and is possible with the amount of skills and know-how you possess, then why not try it? The worst that can happen is that you run out of interest and decide to scrap the idea altogether.