Tbi swap build thread

[cheepin]

I just got it figured out.I had the A-6 pin going to what I thought was a switched 12v source.Well it wasn't.I rewired it to a good 12v source and it fires up.Thanks for all your help.I may have more questions later.You never know.Again thanks.This thread is awesome!!

[Chad77]

O shoot sorry
I have a 82 toyota (Had a Holly truck avenger 470) 283 350/toyota t-case D44/D60 disc all around sitting on 40's

The tbi set up came out of a 88/89 chevy 1/2 ton pickup and the guy it came from said it was a 305 set up but he could not remember if he swap out the injectors when he changed engines.

As of right now I have nothing into the TBI. I got the truck free took that in for scrap and I just sold the Carb

I ll try and find the dead link in this thread and post it i .

[rfmaster]

OK I see now. You have slightly different wiring than what we usually see

On FP socket red-black wire goes to Fuel pump, orange is the BAT side. red-white is used for testing or priming FP.

On oil pressure switch you have only one set of contacts - dash light inidcator is omitted. You'll have to find correct oil pressure switch.

The only way to find out if your TBI injectors are 305 or 350 is by reading part numbers stamped on them. Sometimes injectors are color coded on top flange white/green marking used for 305 and orange - black used for 350.

5235305 was used in 350 applications.

That vacuum switch can be removed in its place CTS can be installed. Alternatively, where you have heater (braided) hose CTS is usually installed. I run heater from water pump bypass port.

//RF

[Chad77]

I was trying to figure out what you ment red-black that is pink-black that goes to a fuse. The other wire coming out of the fuse is tan-white dont that go to the fuel pump? so where does the red-white go?

[rfmaster]

Originally Posted by Chad77

I was trying to figure out what you ment red-black that is pink-black that goes to a fuse. The other wire coming out of the fuse is tan-white dont that go to the fuel pump? so where does the red-white go?

In your posted photo FP relay has the following wires

orange - goes to BAT
pink-black (or red-black ) goes to Fuel Pump via inline fuse which connects to tan-white wire (coiled) - run tan white to fuel pump.
red-white - no connection leave it open (used to test FP)

//RF

[Chad77]

GM5235206 *HPD It dont match your # so Iam assuming Iam good to go?

I am trying to figure out where Iam suppose to put the knock sensor on my 283 block ? Its pretty TIGHT!

[rfmaster]

Originally Posted by Chad77

GM5235206 *HPD It dont match your # so Iam assuming Iam good to go?

I am trying to figure out where Iam suppose to put the knock sensor on my 283 block ? Its pretty TIGHT!

GM 5235206 *RPD orange/black is 61 lbs/hr and a pair should be adequate for 350 (5.7) stock TBI application. There are several other part numbers floating out there.

All small block Chevy blocks should have water jacket drain plugs just above oil pan rail on each side, mid length of the block. Drain plugs are tapped for 1/8NPT. They are PITA to remove in older blocks as plugs tend to rust into the block. Expect to break plug head off and use of easy-out is almost obligatory. That happen to me every time except once! Maybe you'll be lucky. On passenger side it is just before starter.

If you are trying to run TBI on 283 sized engine then 305 injectors should be used - 350 will deliver a bit too much fuel for a smaller engine.

//RF

[Chad77]

Well I guess I have a pair of 350 injectors then and I need to find a pair of 305 injectors

[rfmaster]

Originally Posted by Chad77

Well I guess I have a pair of 350 injectors then and I need to find a pair of 305 injectors

So let me understand this - you have 283 SBC coupled to a turbo 350 driving Toyota transfer case! I build coupled high revving 283 back 20+ years ago for jr dragster project (for an old friend of mine) - it was fun to drive! 283 CID SBC is 4.6L displacement - my local JY's are loaded with 4.3 L V6 Astro vans which use 40 lb/Hr injectors. You can use them on your 283TBI by increasing FP from 12 to 18 PSI - this way injectors will be able to deliver required fuel at WOT. If you are building 283 for TBI make sure that you select cam with wide LSA - 112 to 114 deg and please do not go crazy with duration (at 0.050). On smaller 283 I would try to find cam with 0.050 duration at or below 200 deg. Anything more would cause idle issues due to low vacuum at idle. MAP sensor would read low vacuum and stock tune will run rich. Stock TBI cams are too small (both duration and lift) and should be avoided to performance use. Generally speaking any 'RV' cam with advertised duration 245 to 255deg and LSA 112 deg will work nicely. Try to keep compression around 9:1 to 9.5:1 to one to run on pump gas.

//RF

[Chad77]

Originally Posted by rfmaster

So let me understand this - you have 283 SBC coupled to a turbo 350 driving Toyota transfer case! I build coupled high revving 283 back 20+ years ago for jr dragster project (for an old friend of mine) - it was fun to drive! 283 CID SBC is 4.6L displacement - my local JY's are loaded with 4.3 L V6 Astro vans which use 40 lb/Hr injectors. You can use them on your 283TBI by increasing FP from 12 to 18 PSI - this way injectors will be able to deliver required fuel at WOT. If you are building 283 for TBI make sure that you select cam with wide LSA - 112 to 114 deg and please do not go crazy with duration (at 0.050). On smaller 283 I would try to find cam with 0.050 duration at or below 200 deg. Anything more would cause idle issues due to low vacuum at idle. MAP sensor would read low vacuum and stock tune will run rich. Stock TBI cams are too small (both duration and lift) and should be avoided to performance use. Generally speaking any 'RV' cam with advertised duration 245 to 255deg and LSA 112 deg will work nicely. Try to keep compression around 9:1 to 9.5:1 to one to run on pump gas.

//RF

YES and d44 front and d60 rear!

I dont know nothing about the engine other than it looks like it has been gone through new gaskets, a tube of rebuild grease and sounds RELLY good!

When I had the carb on it I was running it on 87 and it seem to run kinda ruff so for giggles I put 93 in and it ran alot better!

[Chad77]

It is looking like I am going to be pulling out the 238 and sitting in a 350 their goes the out of the norm and doing what every one else is doing . This is due to the fact I am having troubles with getting things lined up to put the tbi on the 283 also a nice talk with rfmaster he made a point about not knowing what cam I have it may not even have enough vacuum to work wright and + I may have a running tbi 350 for free waiting to hear from the guy he owed me a favor .....

[rfmaster]

Originally Posted by Chad77

It is looking like I am going to be pulling out the 238 and sitting in a 350 their goes the out of the norm and doing what every one else is doing . This is due to the fact I am having troubles with getting things lined up to put the tbi on the 283 also a nice talk with rfmaster he made a point about not knowing what cam I have it may not even have enough vacuum to work wright and + I may have a running tbi 350 for free waiting to hear from the guy he owed me a favor .....

Chad

The key to successful conversion (Carb to EFI) is planning and having plenty of patience to boot (money helps, but that stuff is always in short supply!). If you come across a complete donor (aka wrecked truck) - try to grab it whole - it makes putting your rig together easier. What ever you do not be afraid to ask questions!!

//RF

[neto]

I am so glad you are still adding information to this thread. I saved this a while back since I'm putting a TBI engine in my 65 truck. It's ok to run the fuel lines on the drivers side right? Does the fuel line have to be high pressure were you connect to the steel line off of the tank? Thanks.

[rfmaster]

Originally Posted by neto

I am so glad you are still adding information to this thread. I saved this a while back since I'm putting a TBI engine in my 65 truck. It's ok to run the fuel lines on the drivers side right? Does the fuel line have to be high pressure were you connect to the steel line off of the tank? Thanks.

GM used both sides (on different vehicles) to plumb fuel lines. IMHO it does not matter how fuel line are plumbed as long as it is done correctly ( safely). Fuel supply line is 3/8", return is 5/16" and charcoal can use 1/4" line or 5/16"

//RF mobile in Baton Rouge, LA

[FRENCHBLUE72]

Does anyone know if the 87 model computers have a rev limiter built into them?

[rfmaster]

Originally Posted by FRENCHBLUE72

Does anyone know if the 87 model computers have a rev limiter built into them?

There is no rev limiter build into ECM. High RPM potential is limited by distributor ICM and coil.

//RF

[Chad77]

OK I am back at my swap had a few other projects to get done and made some money!

Iam having a brain fart and I don't want to fry my computer, Can some one tell me what positive wires are to be switched energized and size of fuse? Also is their only one positive wire that's to be constant hot ? O one last thing Iam swapping over from points can I just connect the switched positive to the positive that I take off the coil?

[rfmaster]

Originally Posted by Chad77

OK I am back at my swap had a few other projects to get done and made some money!

Iam having a brain fart and I don't want to fry my computer, Can some one tell me what positive wires are to be switched energized and size of fuse? Also is their only one positive wire that's to be constant hot ? O one last thing Iam swapping over from points can I just connect the switched positive to the positive that I take off the coil?

Check Post #8 - it lists wire by wire function for 7747 ECM

As for switching from points to HEI - remove resistor wire from starting circuit (if equipped) and run ignition HOT to both ECM, INJECTOR +12V, and HEI. I would recommend to use BOSCH relay (and separate fuses for safety) to reduce current through ignition key circuits. A while back I posted a circuit diagram to this thread - you'll have to find it.

//RF mobile in Baton Rouge, LA

[phase_one]

I got my engine etc out of a van. I was wondering will the sending unit and pump from the van fit in a truck's gas tank of the same year ?

[rfmaster]

Originally Posted by phase_one

I got my engine etc out of a van. I was wondering will the sending unit and pump from the van fit in a truck's gas tank of the same year ?

The gas tank ring diameter is the same for both P and C/K. Depending on tank dimensions the float swing arm dimensions may be different. Check out part number differences between C/K and P - Spectra has part numbers for both.

//RF

[FRENCHBLUE72]

Thanks rf..

[Chad77]

Again I dont want to fry my computer!

Ok lets see if I have this wright !

A6- pink/blk- switched 12v from the ignition relay.

B1- orn- 12v batt power has a inline fuse.
C16- orange- This wire is tied with B1 so it is a 12volt wire.

C9- purple/wht-Starter crank signal wire. Goes to the small terminal of the starter.

The injector power is from a fused switch power? The one wire lead (RED) coming off the coil that is switched wright?

One other thing I have the red with white tracer coming off the fuel pump relay what do I do whit that? the pic is on page 23.

[rfmaster]

Originally Posted by Chad77

Again I dont want to fry my computer!

Ok lets see if I have this wright !

A6- pink/blk- switched 12v from the ignition relay.

B1- orn- 12v batt power has a inline fuse.
C16- orange- This wire is tied with B1 so it is a 12volt wire.

C9- purple/wht-Starter crank signal wire. Goes to the small terminal of the starter.

The injector power is from a fused switch power? The one wire lead (RED) coming off the coil that is switched wright?

One other thing I have the red with white tracer coming off the fuel pump relay what do I do whit that? the pic is on page 23.

The injector power is supplied from ignition power circuit - usually (GM) this wire is purple (or pink). This wire (ignition power circuit) must have +12 with ignition key in run and crank position. This is important - if you do not have power to injectors (or ECM) during cranking the engine will never fire up! Same goes for HEI power lead!

Yes, use diagram on page 23 as a reference - it is straight out of FSM. The red/wht wire coming out from FP relay is used for testing fuel pump (or priming fuel system) - leave this one unconnected, but make sure that the lead is isolated from ground.

//RF mobile in Baton Rouge

[Chad77]

Rfmaster sorry I have a little bit of ADD and forget things sometimes and other times I tend to over think things . You have it writen out on 23 for what I need to do. again sorry....

[cjracing15]

Wow I can not belive that this thread is still going! Great job RF!!!