I am converting my 89 305 tbi to tpi and I have a speed density unit 90-92 and i have the wiring harness and ecm. i know i need to change the fuel ines from the tank to the chassis and from the chassis to the tpi and also a higher psi sending unit. I also will need a new knock sensor. What else do i need to do/know before i try this mod. Oh yea how long has it taken some of you to do this???

 

Do you plan to get TPI fuel lines and swap them in? Or you planning to run braided hoses?I couldnt find lines for my 86 Vette...mine rusted and nobody made them so I went with braided fuel hoses..if you go that route post that there..got some good tips for that.Not sure how they would fit under the car though..LPE sells the kits to attach -6N style braided lines to 3/8 saginaw fitting EFI filters and fuel rails attachments.(just in case you go this route)

Be sure you have all the related sensors and etc for your application.
You will also need the small parts like the vacuum hoses and etc for the plenum and FPR,egr and etc..make sure you got all that too with the TPI you got.

 

I went from a LG4 (carb) to TPI, took me 2 months, I think I could have had it done sooner, about 3-4 weeks, if I did not paint, polish, sandblast everything to make it pretty.

If you are doing a firebird, you have more work than a camaro, just because you have to move the battery, Camaro TPI have the battery on the right, Firebirds on the left. You might not have to change your dash wires because you already have Fuel Injection.

I have some notes on http://www.3rdgenformula.com go the the "modifying my formula section"

I hope you have another car to go get parts...

------------------
87 Formula 5.1 converted to TPI Yellow/Black
SLP cam, headers, cat-back exhaust
Ported & polished TPI intake
Gil Younger (no yo-yo) Shift Kit
Aluminum Driveshaft
3.73 Posi gear
Baer 12" brakes 4 wheels
Hotchiss strut tower brace
South side machine frame connecters
Custom reinforced control arms and pan hard bar.
Custom Leather interior

87 Formula TPI (5 Speed) Yellow/Gray STOCK

1967 Buick Riviera 430hp Turns high 14's (Not bad for 4300 lbs)

83 Camaro (Parts)
83 T/A (parts)

http://www.3rdgenformula.com

 

Why do you need to replce the fuel line? I though they were the same diameter as the TPI ones?

Can't you just swage the TBI lines to the TBI lines?

Just curious.

 

Hey,

You don't have to replace the metal fuel lines, you only need to replace the rubber ends in the engine compartment, and rubber ends in the rear that goto the fuel sending unit. You also need to replace the sending unit, as well as the pump.. (the new pump won't mount to the old sending unit if I remember correctly)..

Other than that, you're kewl.

On 86-88 firebirds, the battery was on the right as the camaros, on 89+ its on the left (driver side).. Tho I've seen a few mixed inbetween.

BTW, you can send your speed density TBI harness out to Jim (www.jimsperformance.com) and he'll mod it for TPI for you fairly cheap.

The TPI oil sending unit is also the gauge
(has 4 pins, not 3), fortunately if you keep your sensor (thats at the back of the motor) you will be able to use it on your TPI setup..

Make sure you get an ECM w/out passkey.. I put a 86 ecm on mine just to start it, but my car has the passkey module and resister key..
(I also have a 305 AOD chip on a car that has a 355 w/ stick)


-- Joe

www.joesperformance.com

 

anesthes,
As far as I know All Firebirds with TPI had the battery on the driver side because the Air Filter Canister/Box could not be located in front of the Radiator Because of Hood Clearence, and Not on the Driver side because of the Radiator Hose.

The Camaro on the other hand was always straight out the front and had the dual filters.

I own 2 87 formulas with TPI and they both have the Battery on the Driver (left) side.

As for puting Hose clamps on the fuel lines, hmm.. I dunno, The Pressure line from the tank even has a pressure fitting from next to the fuel tank. I Personally thought about doing what you suggested, but did not feel like it would be safe to take on the 40+ lbs of pressure from the pump.

------------------
87 Formula 5.1 converted to TPI Yellow/Black
SLP cam, headers, cat-back exhaust
Ported & polished TPI intake
Gil Younger (no yo-yo) Shift Kit
Aluminum Driveshaft
3.73 Posi gear
Baer 12" brakes 4 wheels
KYB AGX Adjustable Shocks & struts
Hotchiss strut tower brace
South side machine frame connecters
Custom reinforced control arms and pan hard bar.
Custom Leather interior

87 Formula TPI (5 Speed) Yellow/Gray STOCK

1967 Buick Riviera 430hp Turns high 14's (Not bad for 4300 lbs)

83 Camaro (Parts)
83 T/A (parts)

http://www.3rdgenformula.com

 

My 87 Iroc tpi has the battery on the passenger side and has the dual filters in the nose....probly doesnt help but just my .02

-Brian

 

89 formula 350

Battery Left side (driver)

And no, NEVER hose clamp High Pressure Lines.. Youa re just begging to start a fire...

 

Hello,

I dunno about your cars, but in the 10 or so TPI cars i've stripped, every one of them had factory rubbers that were clamped on in the back where the sending unit is. Some of these were 2.8s, but the pressure is the same..

The front is obviously threaded.

As far as the battery goes, I can't remember exactly but I remember seeing a few that were on the passenger side.. Then again, only three of the firebirds i've stripped had factory air cleaners still intact..

-- Joe

 

Reading through a few responses I noticed some are mentioning don't use hose clamps on the high pressure line, I hope no-one took the term "swage" as "hose clamping".

Swaging is a metal to metal contact via inverted or normal flare, or the same using plastic to plastic, etc....basically a compression fitting of some type, depending on how you're going about it.

There's also DOT approved swage lock connectors (cap and ferrule) that are rated at 250PSI and 500PSI burst, routinely used as well.

 

The fuel level sending unit should not need replacing, only the fuel pump in the tank.
The high pressure pump should just mount right on the assembly like the old TBI one came off.
As far as hose clamping, hose clamps came with my Walbro unit to connect a small piece of hose from the pump to the steel fuel supply line in the tank, to get rid of the pulsator. Also, there are hose clamps on my GN and TTA that came from the factory that way everywhere there is rubber hose connecting to the steel supply hose. As long as they are corrosion resistant and are for high pressure fuel, you should be ok, I normally use two on each end though to be sure. My brother uses the same stuff on jet airplane engines that have 500+ psi pressures as long as the clamp is rated for it.
When I converted my truck from TBI to TPI, it took about 1 day to remove all the old stuff and wiring harness, and then about 2 days to install the new TPI, that includes all new accessory brackets.
Go over everything several times to be certain you have all the parts and where everything will go.

------------------
Rob
High Performance & Party page
Pics of my rides past & present and recent party pics!

89 TTA #426 20th Anniversary turbo 3.8 bone stock
79 TA 6.6l - all original stock
94 Silverado Tuned Port Injected
87 Grand National- lil' ole V6, 12.40 @ 108 w/1.79 60'
95 Trans Am Conv.- LT1

 

On your 94 Silverado, is that a Vortec 5700?? I heard thirdgen TPI setups produce major horsepower on those block/head combos..

--Joe

 

No it wasn't, probably would have worked alot better, due to the original cam being a 104 lobe sep., I could never get the fuel curve and timing right without detonation. Rod bearings are real loose now. I'm in process of getting a ZZ4 short block and cam for it along with a set of Sportsman 200 heads that I just had ported and polished. Should run pretty darn good then!
But the low end torque and off the line accelleration are increadibly better even with the slight detonation its still getting.


[This message has been edited by 2QUIK6 (edited June 13, 2001).]

 

Hi,

Cool beans.. I've heard good things about the ZZ4..

Right now my thirdgen has a 350 marine block, bored 030 over, SLP roller cam, forged trw pistons, sportsman II heads, eddelbrock intake..

I've got stock runners and TB on for now.. I just recently fired it up. ITs a little rough.. The car has T-tops, and at one time they were apperently left out, so needless to say I cut the floors out tonight (what didnt fall out allready) and am welding new pans in tomorrow..

-- Joe