dodge89

i was wondering if its possible to put a tbi on a 318 magnum with mild cam plus ROM tune for my 91 d150. that way theres no emissions no less electrical and i dont have to change any wiring?

78D200

You'll still have some emissions, wiring and PCM with a TBI unit. do you mean carb in place of the MPFI?

dodge89

No the truck has tbi. I wanna put tbi on a magnum block in place of the mpfi. Then do mild cam n headers. I'm pretty sure with the tbi theres only the o2 pump.

dodge89

I'm thinking it would be an efficient set up with less sensors. I had a 93 ram charger with 318 police package, I got over 20 mpg. I just got the truck a month ago and having the tranny rebuilt, he said the motor was rebuilt and has new freeze plugs so maybe just magnum heads n roller cam with tbi.

78D200

If the TBI unit mounts to the intake and you can figure out what to do with the wiring (I'm no goo with electrical) then it should work. If you need to swap intakes, then you would be better off spending your money on a better intake for the magnum as the LA intake will not bolt up due to the angle of the mounting holes.

The issue with the magnum motors is that the dome style intake is not very good for flow. I don't know what Dodge was thinking when they designed it.

dodge89

thats why i want to eliminate it. if i knew the angles and the holes and ports line up i could mill it to make it fit.

78D200

If you want to get rid of the MPFI just because of the dome intake, just swap it out with a Mopar performance intake. That way you'll get better flow and be able to keep the MPFI and you won't have to worry about the wiring, PCM programming, etc.

After swapping cams and installing a header back system, you'll want to reprogram the PCM to get the most out of it.

If you want to keep MPFI - http://www.summitracing.com/parts/DCC-5007852/

If you want carb/tbi - http://www.summitracing.com/parts/EDL-7577/

gunnerman

78D200 is right if you chage anything on a engine with a PCM you will have to reprogramm it.

dodge89

i know no matter what ill have to get the PCM tuned. the truck currently has TBI none magnum. i want a roller motor with magnum heads bottom line. the motor thats in it has been rebuilt so could i just use magnum heads and an aftermarket intake for TBI and roller cam?

78D200

I'm not 100% sure about swapping Magnum heads on an LA motor (Never had the opportunity to). With that being said I have read some people say the water passages don’t properly line up. Others have said that they do. What I do know is that angles for the intake bolt holes in the heads between the two are different.

TVLynn or PK1 I’m sure would know. They seem to be very knowledgeable when it comes to the motors. I’d start by asking them.

dodge89

well ive now found out that they started using roller cam in 88 on 318's so im thinking port and polish with stock TBI and CCA-20-612-9 or CCA-20-618-9 with summit long tube headers and PCM tune. what would be a good port size for this set-up?

PK1

dodge 89,

Head swap is not hard but you would need a different intake due to the vertical bolt holes in the mag heads if you have LA heads currently.

Couple things I would caution you about before you spend any money.

Make sure you can find someone who can tune YOUR motor. IAnd will take your logs from your data or a dyno shop and make adjustments. You do not want anything "canned". Especially if you open up the heads. I havent done a TBI motor and dont know anyone who does it. ( not saying it cant be done, I just have no time on modifying that system)

I have done MPFI swaps, custom intakes for FI to change injector angles, ported and cut some kegger manifolds and currently run a M1 fuel injected motor on my parts chaser. If I load the stock tune or a "canned" type tune my motor wont run at all. It took about 10 tunes to get timing, trim and fuel squared away. And I log runs once a week to make sure everything is good to go.

And every time something is changed it needs adjustment to the tune.

Next would be what is the flow of the injectors on there and at what duty cycle do they run at now? How much can you up the flow when your new heads, long tubes and cam need to be fed? Maybe see if the 360 unit is different (larger) and takes same pattern and senors feeds. ( Find a junk yard one )

Both cams work well that you posted above. Depending on your tuners abilities consider an LSA of 114 at a minimum.

Not trying to be a killjoy, just hate to see spend the coin and get stuck.. Hope your build goes smooth.

Good Luck!

dodge89

First time ive ever taken any of my cars to a shop. It took the transmission shop over a month after taking it back 3 times, long story. But remember how I said the motor was rebuilt?? Well there's definatly an aftermarket cam in it I dont know why they painted the motor yellow I see new freeze plugs and motor mounts now it's got the fresh tranny and converter it's deffinetly got some power and decent flow quiet, decent single flow exhaust. I now in 87 they got fast burn heads non magnum and 88 roller cam. The front end is terrible I priced all the parts at 320 on advanced auto and you can get up to 65 % OFF till may 5th. I just don't have the money to invest right now it's a bummer. I have new coil springs already from the ram charger. but cost is 900 truck 780 tranny 130 radiator and I have a new rear bumper and two 2 1/2 inch magnaflows which sound great I want them to dump out behind either side of the rear tire with summit long tube headers.