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135sohc
01-27-2009, 03:53 AM
So I've taken the plunge and my new 2 piece intake is on its way.

swapping over parts isnt a problem. Between all the wiring scraps & pigtails I imagine getting the wiring installed to run all the injectors and adding in the 2nd connector pickup for the HEP wont be a problem.

But what will be a problem (for me anyways), no stock computer exists for the configuration that the car is.

94 (SBEC 2 ?) 2.2 & 5speed. Now pardon the stupid questions that are about to be asked. (The whole socketing, chipping and custom calibration thing is still foreign language to me)

Could a flex fuel computer (2.5L only) be recalibrated to the fueling requirements of a 2.2L ? since its got the drivers for 4 injectors. That I would assume are not present in a TBI computer.

jl93sundance
01-27-2009, 10:59 AM
you can use any 90/91/92 computer with minor pinout changes, though I think you will need at least a turbo computer to compensate for the extra injector driver even if your going to socket it. Pm Wvrampage he did a rampage once, but I think he just used a whole turbo harness and a turbo computer.

Murphy
01-27-2009, 12:04 PM
doing this with a 94 is going to be quite a challenge. A FFV computer is more trouble than its worth since it has extra sensors to measure gas / m85 concentration and fuel adjustment for it, tho htat might be your only option. to make up for the 2.2/2.5 difference you could jsut lower your fuel pressure. I dont think D-Cal is really setup to be used with SBEC2.

jl93sundance
01-27-2009, 12:44 PM
doing this with a 94 is going to be quite a challenge. A FFV computer is more trouble than its worth since it has extra sensors to measure gas / m85 concentration and fuel adjustment for it, tho htat might be your only option. to make up for the 2.2/2.5 difference you could jsut lower your fuel pressure. I dont think D-Cal is really setup to be used with SBEC2.

Really I see no difference in sbec 1+2 my 94 sundance which I just converted to 2.5 turbo with 90/91 electronics will run on both sbec computers so really I see there is not too much of a difference, except for maybe a few pinout changes IMO.

turbovanmanČ
01-27-2009, 02:21 PM
Your going to need a harness anyhow, so I would grab an earlier harness, 90's and matching computer, it will make it alot easier I think.

What car?

chilort
01-27-2009, 04:04 PM
I've got a '93 FFV computer from a 2.5L auto. I was hoping to do something with it that isn't going to happen. I paid $30 for it. If you want it, it is yours for $30 plus shipping. Just send a PM.

135sohc
01-27-2009, 04:19 PM
Your going to need a harness anyhow, so I would grab an earlier harness, 90's and matching computer, it will make it alot easier I think.

What car?

I dont know. I think it would much easier to add on the additional wiring for the extra injectors, HEP pickup. And relocate the wiring connectors for the TPS and idle speed motor to the other side of the engine.

everything else is (according to the FSM) the same layout as a regular TBI engine. The Map sensor & purge solenoid are the same between the two as well.

car is a 94 P-body

turbovanmanČ
01-27-2009, 04:44 PM
I dont know. I think it would much easier to add on the additional wiring for the extra injectors, HEP pickup. And relocate the wiring connectors for the TPS and idle speed motor to the other side of the engine.

everything else is (according to the FSM) the same layout as a regular TBI engine. The Map sensor & purge solenoid are the same between the two as well.

car is a 94 P-body

I think its alot more work than you think. If you picked up an earlier P body, say 90/91, then it should be mostly plug and play and you have a computer you can easily mod.

135sohc
01-27-2009, 05:07 PM
I think its alot more work than you think. If you picked up an earlier P body, say 90/91, then it should be mostly plug and play and you have a computer you can easily mod.


That would be ideal but those parts dont exactly fall out of the sky around here nor online here or elsewhere.


Guess I'll be keeping it for a conversation piece after all.

jl93sundance
01-27-2009, 05:15 PM
I think its alot more work than you think. If you picked up an earlier P body, say 90/91, then it should be mostly plug and play and you have a computer you can easily mod.

I completely agree, Use a 90/91 turbo harness+computer, there will be some minor pinout changes for headlights turnsignals. but at that point your halfway there you should just turbo it lol

Murphy
01-27-2009, 05:24 PM
you could jsut wire the injectors in parallel. that way you dont need to change the wiring or computer. you do need specific injectors tho and i dont remember what kind. I htink i saw it done before over on TD

edit: LINKY! http://www.turbododge.com/forums/f11/f56/128988-my-mpi-conversion-w-pics-d.html

135sohc
01-27-2009, 05:55 PM
I completely agree, Use a 90/91 turbo harness+computer, there will be some minor pinout changes for headlights turnsignals. but at that point your halfway there you should just turbo it lol


I do not want the hassle, expense and reliability issues of a turbocharger right now. I'd just like 4 injectors vs 1


Eventually (read as: if I ever stop procrastinating :o) I'd like to pickup a solid CB core and rebuild it into a nice T2. forged crank, carrillo rods, wiseco's, 4 bolt mains, ect but thats a long ways off.

turbovanmanČ
01-27-2009, 05:59 PM
I do not want the hassle, expense and reliability issues of a turbocharger right now. I'd just like 4 injectors vs 1


Eventually (read as: if I ever stop procrastinating :o) I'd like to pickup a solid CB core and rebuild it into a nice T2. forged crank, carrillo rods, wiseco's, 4 bolt mains, ect but thats a long ways off.

Reliability issues, :confused:

Anyhow, if your not in a panic, just keep looking.

135sohc
01-27-2009, 06:37 PM
Reliability issues, :confused:

Far less overall to go wrong on a N/A engine. Now I'm not saying you cant have a reliable turbocharged engine. if its stock ;) and meticulously maintained. But mile for mile a TBI engine will go farther and longer than its turbo cousin.

jl93sundance
01-27-2009, 07:47 PM
Far less overall to go wrong on a N/A engine. Now I'm not saying you cant have a reliable turbocharged engine. if its stock ;) and meticulously maintained. But mile for mile a TBI engine will go farther and longer than its turbo cousin.

That may be true to a point, but which motor will you have 10x more fun with?;)

Aries_Turbo
01-27-2009, 09:01 PM
ive had 0 issues with my turbo engine. i did trash 1 clutch (cheapo replacement) and a 140k input shaft bearing on the trans but that was cause i was hammering it with 20psi all the time. :)

you dont need all those fancy parts in your list for a turbo engine either. stock everything and a set of pistons is good for more than the stock head can flow.

id swap in a turbo harness and ecu on the now MPFI motor and then tune the Vacuum part of the maps to get good power and mileage from your NA engine. youll have full control of timing and fuel so you should be able to tweak it alot without much hassle.

Brian

GLHNSLHT2
01-27-2009, 09:12 PM
+1 you don't need a turbo to run the turbo ECU. The ECU will just never see boost.

135sohc
01-27-2009, 09:43 PM
you dont need all those fancy parts in your list for a turbo engine either. stock everything and a set of pistons is good for more than the stock head can flow.

I have no intentions of building a stock factory T2. Would rather overbuild it and not have to touch it again. and make future power upgrades easier.

Aries_Turbo
01-27-2009, 10:29 PM
its already overbuilt stock. i can see the 4 bolt mains as the 2 bolt are seeming to shift a little at ~500hp. id do the k1 rods over the full on carrillo for the huge price difference vs insanely small difference in quality. :)

i see your point though. :)

Brian

Vigo
01-27-2009, 10:57 PM
Reliability issues,

haha from the man who has one of the more impressive collection of broken stuff on the forums. :)

turbos are WAY less reliable and more likely to break then the tbi's, but that doesnt mean the turbo engines are unreliable at all.. it just means tbi's are insanely reliable. in my experience.

jl93sundance
01-27-2009, 11:07 PM
haha from the man who has one of the more impressive collection of broken stuff on the forums. :)

turbos are WAY less reliable and more likely to break then the tbi's, but that doesnt mean the turbo engines are unreliable at all.. it just means tbi's are insanely reliable. in my experience.

and insanely slow:yuck:, which is why i'll never own another tbi again:nod:

turbovanmanČ
01-27-2009, 11:50 PM
haha from the man who has one of the more impressive collection of broken stuff on the forums. :)

turbos are WAY less reliable and more likely to break then the tbi's, but that doesnt mean the turbo engines are unreliable at all.. it just means tbi's are insanely reliable. in my experience.

Well yeah, when you push the envelope, or ignore your guages, ;)

If you leave it stock, it will run reliably for 100's of 1000's of miles, :thumb:

GLHNSLHT2
01-28-2009, 12:04 AM
Built/driven/maintained right a Turbo is just as reliable as a TBI even pushing 300+hp.

capev86
01-28-2009, 05:05 PM
a turbo dodge is very reliable, but not quite as reliable as a tbi. premium gas is too expensive for a daily driver. an mpi conversion is the best compromise - the flow and efficiency of the turbo intake and fuel with softer n/a fuel requirements and a better flowing exhaust manifold. with a few tweaks a tbi car can make a nice daily driver. power is academic these days anyway....someone else always has more!

i plan to go 2.5 T2 with 3" exhaust and swing valve on my 86 k wagon, but first i will be running a 2.5mpi when i restore the car and saving for the rest of the turbo parts. i have a 90/91 t1 auto harness and will likely run a socketed turbo computer. the mexican 90/91 mpi calibration is available for download...you just need a socketed computer board and burner to do it. i will also be using a lockup converter - hence why the electronics upgrade besides making it easier to go turbo later!

another trick for getting better performance out of a car is a 5spd swap. wish my 91 dynasty had a 5spd. the stock automatic was definitely the limiting factor when it came to spirited driving (well that and the wooshy suspension)

Vigo
01-28-2009, 08:53 PM
there is no one vacuum line on a tbi that can crack or pop off and result in a grenaded motor. even if you have low fuel pressure and WOT all the time you'd be lucky to break anything.

not that us as 'car people' give a ---- about the common man's idea of reliability. but in the layperson's eyes, the above situation would be like an anvil falling from the sky. something you just shouldnt have to think about.

well all have gauges and pay attention to our cars ( and we still occasionally break them) so we dont go blaming it on the car being 'unreliable' when ---- happens. We know we could have done something to prevent it and it's probably our fault.

for the guy that knows jack ---- about cars and doesnt maintain them, a tbi will STILL run forever and the turbo car will come apart at some point, leading it to be, in the common man's view, unreliable.

its semantics, i know. but try and break a tbi. I bet it'll take you while to do it. Most of us could go out and blow up our turbo motors in minutes.

its a price we happily pay to go faster.

Aries_Turbo
01-28-2009, 10:32 PM
i have a good tall deck 2.5L sitting in a k car. ill spray it till its death! :) ehehhe

Brian