TBI system to MPFI using stock TB
#1
TGO Supporter
Thread Starter
Join Date: Oct 2000
Location: Wilmington NC
Posts: 1,231
Likes: 0
Received 0 Likes
on
0 Posts
Car: C1500
Engine: 350
Transmission: 700r4
Axle/Gears: 2.73
TBI system to MPFI using stock TB
I have an '88 350 TBI truck that I would like to go Multiport with, but keep the stock TBI unit as a throttle body minus the injectors. I know that Edelbrock makes a kit to do this, but it does not work for the '88 model year ecm. Besides I think it's over priced.
Is it possible to take a carb/tbi manifold and have it drilled for 8 injectors and a fuel rail? I thought I've seen it done, before. I have also thought that the TBI ecm would probably need to be dropped and I could use a TPI or aftermarket computer spliced into my stock wiring.
It seems to me the only real expenses would be a chevy fuel rail/injectors, a TPI ecm and chip for a 350, and the cost of machining the holes in my intake, plus a fuel pump. I figure it would run ok on a stock TPI chip, but I know it would need to be tuned at some point.
Is this possbile?
Is it possible to take a carb/tbi manifold and have it drilled for 8 injectors and a fuel rail? I thought I've seen it done, before. I have also thought that the TBI ecm would probably need to be dropped and I could use a TPI or aftermarket computer spliced into my stock wiring.
It seems to me the only real expenses would be a chevy fuel rail/injectors, a TPI ecm and chip for a 350, and the cost of machining the holes in my intake, plus a fuel pump. I figure it would run ok on a stock TPI chip, but I know it would need to be tuned at some point.
Is this possbile?
#3
TGO Supporter
iTrader: (1)
Re: TBI system to MPFI using stock TB
I am considering something similar in future. maybe next year/season. not sure how successful you would be converting a standard manifold by welding bungs. seems i read it is difficult to get it right and flow correct. i would lean toward a victor jr efi or a prof prod unit. I have a 7.4L TBI that might be my TB for port injection but I really want a 4 barrel.
stock harness compatible with a TPI ECU? check Painless Products for an adapter. I use Hammed EBL which will fire port injectors and is compatible with my TBI harness. Seems I am close.
stock harness compatible with a TPI ECU? check Painless Products for an adapter. I use Hammed EBL which will fire port injectors and is compatible with my TBI harness. Seems I am close.
#4
TGO Supporter
Thread Starter
Join Date: Oct 2000
Location: Wilmington NC
Posts: 1,231
Likes: 0
Received 0 Likes
on
0 Posts
Car: C1500
Engine: 350
Transmission: 700r4
Axle/Gears: 2.73
Re: TBI system to MPFI using stock TB
I am considering something similar in future. maybe next year/season. not sure how successful you would be converting a standard manifold by welding bungs. seems i read it is difficult to get it right and flow correct. i would lean toward a victor jr efi or a prof prod unit. I have a 7.4L TBI that might be my TB for port injection but I really want a 4 barrel.
stock harness compatible with a TPI ECU? check Painless Products for an adapter. I use Hammed EBL which will fire port injectors and is compatible with my TBI harness. Seems I am close.
stock harness compatible with a TPI ECU? check Painless Products for an adapter. I use Hammed EBL which will fire port injectors and is compatible with my TBI harness. Seems I am close.
I don't think my harness is compatable with TPI, I know I would have to rewire the connector for the TPI plug. I already have a TPI computer laying around in my junk, I'm just not really sure if it works.
Is the EBL with the port mod compatable with a TBI harness?? I've been looking over those products for the past week. I wasn't sure what the "port mod" really is? Is that a TBI comptuer that can run a TPI setup or a flashable TPI comptuer? Can I get one to fit my '88 truck harness with no issues?
#5
Junior Member
Join Date: May 2007
Location: chi, Illinois
Posts: 85
Likes: 0
Received 0 Likes
on
0 Posts
Car: Pontiac T/A
Engine: 305
Transmission: 700R4
Axle/Gears: Borg Warner 9-Bolt w/ 2.77 gears.
Re: TBI system to MPFI using stock TB
I have an '88 350 TBI truck that I would like to go Multiport with, but keep the stock TBI unit as a throttle body minus the injectors. I know that Edelbrock makes a kit to do this, but it does not work for the '88 model year ecm. Besides I think it's over priced.
Is it possible to take a carb/tbi manifold and have it drilled for 8 injectors and a fuel rail? I thought I've seen it done, before. I have also thought that the TBI ecm would probably need to be dropped and I could use a TPI or aftermarket computer spliced into my stock wiring.
It seems to me the only real expenses would be a chevy fuel rail/injectors, a TPI ecm and chip for a 350, and the cost of machining the holes in my intake, plus a fuel pump. I figure it would run ok on a stock TPI chip, but I know it would need to be tuned at some point.
Is this possbile?
Is it possible to take a carb/tbi manifold and have it drilled for 8 injectors and a fuel rail? I thought I've seen it done, before. I have also thought that the TBI ecm would probably need to be dropped and I could use a TPI or aftermarket computer spliced into my stock wiring.
It seems to me the only real expenses would be a chevy fuel rail/injectors, a TPI ecm and chip for a 350, and the cost of machining the holes in my intake, plus a fuel pump. I figure it would run ok on a stock TPI chip, but I know it would need to be tuned at some point.
Is this possbile?
#6
Supreme Member
Join Date: Jul 2005
Location: North Central Mass.
Posts: 2,123
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1985 Berlinetta
Engine: Megasquirted TPI
Transmission: Transgo 700R4
Axle/Gears: 3.42
Re: TBI system to MPFI using stock TB
Alot of guys are doing this on the megasquirt forums. They seem pretty happy.
#7
Junior Member
Join Date: May 2007
Location: chi, Illinois
Posts: 85
Likes: 0
Received 0 Likes
on
0 Posts
Car: Pontiac T/A
Engine: 305
Transmission: 700R4
Axle/Gears: Borg Warner 9-Bolt w/ 2.77 gears.
Re: TBI system to MPFI using stock TB
Yes you can. We did it with a gm computer and the factory wiring harness that was already in the car which saved a boat load of money. The car looks so stock you couldn't tell it was modded (until you ran him)
Trending Topics
#8
TGO Supporter
Thread Starter
Join Date: Oct 2000
Location: Wilmington NC
Posts: 1,231
Likes: 0
Received 0 Likes
on
0 Posts
Car: C1500
Engine: 350
Transmission: 700r4
Axle/Gears: 2.73
Re: TBI system to MPFI using stock TB
TRUST me when I say this. It can be done I've done it and it makes REAL GOOD POWER. I did it with a stock tbi harness (non spliced) EBL controls, 51 mm tbi and everything you need with the smog stuff hooked up. Car has killed modded LS1s, LS2s, muddstains, vettes and chargers. They didn't think that setup could make the power it's making.
#9
Junior Member
Join Date: May 2007
Location: chi, Illinois
Posts: 85
Likes: 0
Received 0 Likes
on
0 Posts
Car: Pontiac T/A
Engine: 305
Transmission: 700R4
Axle/Gears: Borg Warner 9-Bolt w/ 2.77 gears.
Re: TBI system to MPFI using stock TB
I used the edelbrock muti-point conversion manifold that is already set up for the injectors. You can also use the holley manifold that comes with the efi kit. Or have a speed shop fab up one on you own manifold. We have one that we got from summit for his stage 2 set up. It comes set up for 8 inj and you can buy the matching fuel rails too. We went this way because the tune port swap would have been a nightmare and to upgrade for more power would have cost too much plus the harness swap. If you want I can post some pic of both manifolds.
#10
TGO Supporter
Thread Starter
Join Date: Oct 2000
Location: Wilmington NC
Posts: 1,231
Likes: 0
Received 0 Likes
on
0 Posts
Car: C1500
Engine: 350
Transmission: 700r4
Axle/Gears: 2.73
Re: TBI system to MPFI using stock TB
I used the edelbrock muti-point conversion manifold that is already set up for the injectors. You can also use the holley manifold that comes with the efi kit. Or have a speed shop fab up one on you own manifold. We have one that we got from summit for his stage 2 set up. It comes set up for 8 inj and you can buy the matching fuel rails too. We went this way because the tune port swap would have been a nightmare and to upgrade for more power would have cost too much plus the harness swap. If you want I can post some pic of both manifolds.
#11
Junior Member
Join Date: May 2007
Location: chi, Illinois
Posts: 85
Likes: 0
Received 0 Likes
on
0 Posts
Car: Pontiac T/A
Engine: 305
Transmission: 700R4
Axle/Gears: Borg Warner 9-Bolt w/ 2.77 gears.
Re: TBI system to MPFI using stock TB
Right now he has the Edelbrock tbi conver manifold on. Future plans are to use the holley manifold and accel 1350cfm TB on a bigger motor which he already has. But I can tell you what you're going to need to make 375-400hp+ to the rear wheels with the tbi conver set up.
#12
TGO Supporter
iTrader: (1)
Re: TBI system to MPFI using stock TB
QUOTE: Is the EBL with the port mod compatable with a TBI harness?? I've been looking over those products for the past week. I wasn't sure what the "port mod" really is?
yes. check out dynamicefi.com. For me 1984 Vette. No. I needed to have my 8746 -EBL computer modified to match up to stock Vette harness. Called HAM done by speedtronics.net
QUOTE: Is that a TBI comptuer that can run a TPI setup or a flashable TPI comptuer? Can I get one to fit my '88 truck harness with no issues?
Mine is a 8746 computer that is no longer considered as such. Now it is EBL computer. Just looks like a GM unit. Flashable. yes with that option. I will say no longer a TBI nor a TPI unit. EBL unit. Can be ordered TBI or TPI-Port Inj. Again see EBL site for more info on that "option".
yes. check out dynamicefi.com. For me 1984 Vette. No. I needed to have my 8746 -EBL computer modified to match up to stock Vette harness. Called HAM done by speedtronics.net
QUOTE: Is that a TBI comptuer that can run a TPI setup or a flashable TPI comptuer? Can I get one to fit my '88 truck harness with no issues?
Mine is a 8746 computer that is no longer considered as such. Now it is EBL computer. Just looks like a GM unit. Flashable. yes with that option. I will say no longer a TBI nor a TPI unit. EBL unit. Can be ordered TBI or TPI-Port Inj. Again see EBL site for more info on that "option".
#13
Junior Member
Join Date: May 2007
Location: chi, Illinois
Posts: 85
Likes: 0
Received 0 Likes
on
0 Posts
Car: Pontiac T/A
Engine: 305
Transmission: 700R4
Axle/Gears: Borg Warner 9-Bolt w/ 2.77 gears.
Re: TBI system to MPFI using stock TB
That's the way to go. Little cost easy hook up and lots of tunning options.
Thread
Thread Starter
Forum
Replies
Last Post
db057
TBI
10
08-11-2015 10:11 PM
305, 350, 350tbi, 4barrel, 74, converting, ecm, market, megasquirt, mod, motorvation, mpfi, port, systems, tbi