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smoky02 11-17-2008 06:31 PM

Tune-port install
I've got 2 305 tune-ports that run, and I'm wanting to put one in my truck. Is there a sticky about this or anything so I can see what all I need or can someone fill me in? Thanks in advance.


smoky02 11-17-2008 11:23 PM

Re: Tune-port install
For real, no one has any input?

Brad 11-17-2008 11:43 PM

Re: Tune-port install
I know Akattack had a tpi on a previous truck, he might be able to help you out.

harlyworkr 11-17-2008 11:47 PM

Re: Tune-port install
I am in the process of finishing mine up. WOW what an undertaking, I hope you have patience for this.

vasquezmrysvll 11-17-2008 11:52 PM

Re: Tune-port install
its really not all that difficult, iv switched my v6 camaro over to a tpi 350. if you have any questions PM me. a GREAT source for info on the TPI engines is you will find TONS of info and TONS of people willing to help out.:j69:

vasquezmrysvll 11-17-2008 11:55 PM

Re: Tune-port install
oh... why TPI? they look cool, but they flat line at about 45-4800 rpm. im planning for a LTX swap myself :metal:

Ackattack 11-18-2008 12:27 AM

Re: Tune-port install
Yeah, I had one in my GMC.

Basically I used a harness from Painless. The wiring was easy once you read the direction carefully. (I had the power wire to the computer hooked up to a hot while in the run position....not the crank position :) )

Other than that I used the stock fuel lines, spliced in a fuel pump that was mounted on the frame, and extended them using rubber hoses (efi rated) up to the stock TPI connection point.

I think that was about it as far as getting the engine to run.

Honestly, I wasn't impressed with my TPI 350. I had heard how much low end grunt these engines had. I don't know if mine never ran right or what (no obvious signs of problems) but I wasn't impressed. I think I ran something like 15.9 @ 86 mph at the track. I figured that that was about 240 RWHP, so it put down the power (considering what its factory rating at the crank was) but driving it, my carbed 327 was more fun. I did get something like 18mpg out of it with 3.73s and a 700r4.

Good luck!

vasquezmrysvll 11-18-2008 12:35 AM

Re: Tune-port install
15.9 sounds about right, and i belive the most potent tpi produced was 230 flywheel HP. low end torque was pretty stout, but yah 18-22 mpg is expected from a 700r4 with 3.73s. but like i said earlier.....they look cool, expecially pollished.

smoky02 11-18-2008 01:11 AM

Re: Tune-port install
My dad is actually the one wanting the TPI. He's also got a complete LT1 setup, but we figured this would be easier to do. And hopefully cheaper. As far as my truck goes, I've been thinking about putting the TPI on my vortec 350 and seeing what kind of power she will make.

piecesparts 11-18-2008 01:18 AM

Re: Tune-port install
The TPI motors flatline at 4800 RPMs, due to the port design on the heads. Change the heads to a set of Vortec heads and put on a baseplate for the vortec hook up and change the profile from 4800 RPMs to 5600 as a top out. I have a motor that I did this to and then sold it to a friend. The intake change and the new injectors produced a 375 HP motor with a lot of torque.

A TPI 350 settles in around 240 HP in stock form, and has a lot of pick up that a carb does not have. That is due to the design of the injection and the use of ALL of the cylinders at their peak fuel charges. A carb motor is lacking on fuel charge at the outer ends of the intake manifold so there is losses in the perofrmance in those cylinders.

Go the the Jags that Run website and they ahve an install book that has everything that you would want to know and a list of parts that will holp you install.

smoky02 11-18-2008 01:25 AM

Re: Tune-port install
Ackattack, I didn't think you could use rubber hose when dealing with EFI? And also, if we are gonna be running the TPI all stock will I still need to have the computer flashed or anything? And how makes the better harness?

vasquezmrysvll 11-18-2008 01:38 AM

Re: Tune-port install
you should be ok with the ecu in stock form,but it would be a good idea to have VATS and the egr taken off the ecu? you can get high pressure rubber fuel line, but i would go with steel lines spliced together with compression fittings. high pressure fuel leaks are BAD.and aftermarket tpi setups yeald a ton more power than the stock unit. the problem is not the heads, its the diameter and length of the runners that limit performance. accel,edlebrock,tpis,holly,slp and arizona speed and marine all make aftermarket upgrades for the tpi. ohh...bbk is said to be coming out with on soon?

smoky02 11-18-2008 01:54 AM

Re: Tune-port install
Is TPIS a good brand? I was doing some research earlier and came across them a few times. What runners are you talking about limiting power?

71swb4x4 11-18-2008 02:04 AM

Re: Tune-port install
I put TPI in a truck.
These links will help you:
I bought the Helms manual for the car that I pulled the TPI out of and that helped immensely too.

I used the stock harness. I used chevythunder and the Helms manual to pull the things off the stock harness that I didn't need.
I used the stock computer, sort of. I had stock chip reburned to accept my motor (305 to 350) as well as my heads and cam. I had Brian at reburn the chip.

I put a rear tank in with an intank pump and ran steel lines to the engine and back. The tank I got from board member fuelcellguy.
My air intake ducting I got from Jags That Run. I also got my VSS from Jags That Run.

vasquezmrysvll 11-18-2008 02:12 AM

Re: Tune-port install
tpis products are good. the runners are located between the plenum(upper intake) and the base(lower manifold) thay look like bent tubing. 4 runners per side.

smoky02 11-18-2008 02:17 AM

Re: Tune-port install
Oh ok, I know what the runners are now. And thank you all for all of your inputs. So you just used the stock harness and modified it to work for your application?

Andy4639 11-18-2008 09:19 AM

Re: Tune-port install
Like I said in my PM, I didn't have all these choices back in 1989. If you have the wiring harness you can use it if it's not cut up. Make sure you mark everything that is unpluged for reinstallation. Less headaches when putting it back together. This was the reason for the S&P wiring harness.
If you are going with the 700-R4 transmission you will need to cut the drive shaft off some too. I don't remeber the amount but I'm sure someone knows.
My motor was built stock and I'm getting 18-20 MPG out of it. No it want win no race contest but for everyday driving you can't beat it. It cranks right up and ready to go on cold mornings here in SC.
The high pressure rubber fuel lines are fine to use. Just make sure you use a good connector with them.

c10addict 11-18-2008 09:32 AM

Re: Tune-port install
1 Attachment(s)
I am glad other people say they lack power... I know mine sure does! At least it looks pretty! I tried the painless harness and will NEVER go that route again.. THere was a problem with my harness and their customer service leaves a lot to be desired. Call the guys at Street and Performance.. They know their stuff and make some great products!

71swb4x4 11-18-2008 10:54 AM

Re: Tune-port install

Originally Posted by smoky02 (Post 2979647)
So you just used the stock harness and modified it to work for your application?

I used the stock harness. I removed the smog wiring, AC wiring, windshield washer pump wiring, fan wiring (I used my stock engine driven fan), and a couple other things I think. Once I had removed the extras the was MUCH easier to work with. Not only that, but I learned a ton about the TPI system simply by modifying the stock harness.

My TPI was very peppy down low, plenty of power, but it did quickly run out at the higher RPM's. The long runners do that. I wasn't building a race truck, so I liked having my power down low.

smoky02 11-18-2008 10:30 PM

Re: Tune-port install
Awesome, thank you guys for all the input. Let me know if ya'll can think of anything else.

airdale94 11-19-2008 06:18 PM

Re: Tune-port install
You can also just run it in open loop w/o the computer. There's some on info on the net about it.

vasquezmrysvll 11-19-2008 06:43 PM

Re: Tune-port install

Originally Posted by airdale94 (Post 2981916)
You can also just run it in open loop w/o the computer. There's some on info on the net about it.

please understand that "open loop" means that the engine runs on stored memory in the computer, when the engine comes up in temperature it enters "closed loop" meaning the computer adjusts fuel ratio and timing based on various readings from various sensors. the engine WILL NOT RUN without some sort of engine managment. ie: the computer

danman987123 11-19-2008 08:24 PM

Re: Tune-port install i got my harness from their.....OMG WAS THE CHEAPEST PRICE I FOUND AND THE BEST QUALITY.....guy uses all delphi connectors, great perfect harness i pick him before painless anyday. and he is cheaper than anyone...

smoky02 11-21-2008 12:00 AM

Re: Tune-port install
I checked out the looks really good. Is that the harness that you are using? or do you know anyone that's using one of there systems?

LuckyHenriksen 11-21-2008 01:33 AM

Re: Tune-port install
Do the LT1

For the time your going to spend wiring, you could do an LSX of some sort

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