Inliners International Forums General Discussion Hi Performance TBI or MPI

I am looking at the possibility of going down the road of fuel injection for my 292. I am curious if there ever was an install of an EFI for the 292 or if there is a late model inline that would match up the intakes of the 292. I have been considering figuring out a multi-port injection system bringing about more reliability and economy for my 292 with possibly more power.

Eventually, the consideration has been to have this run with E85 as well so that should be a consideration as well.

Any thoughts?

First there wasn't an 292 with OEM EFI.

If you do a search what you will find is that the 292s with EFI are using the later Clifford intake manifold. From what I've seen on that auction site the early Clifford's do not have boss on top of the runner. The boss that is on top of the later Clifford's is being machined for injectors. I've seen mention of using the injectors and computer from 4.6L V6 . If you intend to switch to E85 you have to have injectors 30% more fuel than what is required for gas. I'm considering doing the same thing, but I'm not yet close enough to have considered more than the above.

btw There are some folks in the business of installing EFI engines that say as far as economy is concerned there is not that much difference between TBI and MPI.

Larry

You may find this topic of interest.


http://www.inliners.org/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=3;t=000997#000000

For ease of installation and for a 1st time EFI user TBI is WAY easier to install. MPI take a lot more machining to get the injector bungs and fuel rail "right". Either way you need to start with a 4bbl intake mainifold.

If you use megasquirt as the controller then the rest of the parts come out of the junkyard. An entire TBI installation can be done for under $500. Does it come in a box.. no does it take some reading and re-reading yes.

If you wanted help to do the conversion and could prep the fuel tank for the supply and return lines. If you took a road trip here we could do the converions to TBI in about 8 to 12 hours and you would be on your way.

Your a days drive from here - come up throught Sandpoint. I've been hoping that someone close enough wanted to do the swap.

Once the TBI system is running then if you wanted to convert to Port injection is mainly mechanical work and some tuning.

If your interested we can discuss this off forum.

I'd like to do a time lapse video of the conversion so folks can see its not so hard.

Thanks folks. I know the 292 never came with efi on the engine. I was curious if a 250 or some other engine mapped the intake pattern appropriately.

I have been leaning towards tbi to begin with, but since my carb is mostly running currently, I figured that the jump to mpi is basically time in machining and trips to the junk yard. My goal in doing the conversion is not necessarily getting up and running with the most new parts possible, I am taking a side route off budget here by doing this, so just trying to find the most economical route.

If there is not a pattern substitute, then it means I go looking for 292 junk yard dog intakes and then machine my own MPI.

next question, performance of a MPI vs. a TBI, which would be better and is it really a bigger boon to take on a MPI?

i have a MPI on my 292. i made it myself as there is no factory offerings for any of the 230-250-292 motors. basocally take a 4 bbl intake of your choice and machine it to accept fuel injectors and start fabbing up parts for the rest. the tunablitiy of MPI is un matchable when combined with a wideband O2 sensor and electronic timing control. tom

Either way you need to start with an aluminum 4bbl intake and go from there. Some folks say an Offy is better low - mid rpm than the clifford..

What are you running for a carb? Monojej?

I have the original 1bbl carb. Since I am starting from a blank slate, I just wanted to know the performance and emission gains from going to either TBI or MPI. I know my emissions are going to be higher with my carb, but I only hear that emissions are better and that there are major performance gains. Are talking that my 12MPG going to go towards 25 MPG (not likely) or how much more torque or HP could I potentially gain?

I am looking for cost and time justifications towards my future thinking. I am going to tell you I am leaning towards a MPI to make a fully custom piece, but if my leanings are for naught then maybe I shouldn't spend my time on that. This is all future thinking and planning which is smart to do, but this will take some time to plan and consider.

Again I thank you for your time and consideration. If there is a place to go to get this information, then great.

Unless you ae looking for much greater power levels than you currently have, going with MPI won't gain you much over what a good TBI setup will deliver. I know- I've gone through it!

I'd start with an aftermarket intake & a 4.3 or 5.7 TBI unit powered my Megasquirt. Easy swap!