megaracerx

can somone name everything i will need for this swap?

also what power gains will i get? my can is now and LG4 (carbed).

and is the gas mileage better??

thanks in advance

DeWynter

To do a complete conversion you will need TPI Heads, intake manifold, right and left runners, plenum, throttle body, Mass air flow meter(for the MAF style or no MAF if you want the speed dencity type) TPI Cam, and exhaust manifolds, TPI AIR system and hoses, Wiring harness and computer. Oh and the proper water neck.
If you just want the minimum it would be a TPI intake (manifold runners plenum waterneck)Computer, and harness. Yuo will have to mod the intake manifold to bolt to the old style heads if that is what you have or find an intake manifold for a corvette. You will also have to make sure the accesory mounts are the same for the tpi setup and yours, plus you may have to switch pullies around to make everything pass.

megaracerx

oh...dont think iwanna mess with all that...lol

Zepher

iTrader: (1)

Actually, you don't need to do all that to convert to TPI.
Main things are the TPI intake setup with harness, ECM, all sensors, EFI Fuel Pump, some under dash wiring.

My Carb Setup,


After converting to TPI,

megaracerx

how much did it cost you to convert to TPI, and how long did the work take?

contactpatch

Enlighten me,
why would anyone with carb, want TPI?

John Millican

iTrader: (1)

Here we go again.............

ChevelleFan

iTrader: (4)

Because I'd rather tune with my laptop and not get gas all over my hands anytime a tuning adjustment is needed.

Because I can datalog my runs and have more information to make tuning adjustments with.

Because I want better mileage.

Because I hate having to change the secondary spring on my Holley to a stiff spring so it won't suck down the gas (as much) when I'm running 3500 RPM down the freeway, which then leaves me in a less-than-ideal state when a Rustang or Fast-n-Furious VTEC wants to run me. (why is r|cer a banned word here?)

Because it just looks cooler than carb does.

These are my reasons for putting a TPI in my Chevelle. (which I'll probably upgrade to a Stealth Ram -- all the same in a carb vs. EFI debate). Is it more complex than carb? You bet, but I'm up to the challenge.

-Dave

megaracerx

do you get a better ( quicker) throttle response with TPI?

ChevelleFan

iTrader: (4)

I'm not sure this is a 'fair' question. A lot depends on the tune and the manifold design, so it's not really and apples-to-apples comparison.

Carbs can provide very good throttle response IF... *IF* one wants to go through the effort to tune all the different fuel circuits properly. (idle, main jets, accelerator pump, power valve, secondary jets, secondary accelerator pump, etc). It can be done. But that's a topic for a different forum.

My carb-to-TPI swap is probably 75% done. My last big hurdle is plumbing the fuel system, since my car never had EFI. Wiring is all done. Fuel system is partially plumbed. One of these days, I'll put a real web page together with all the pics I've taken, but here's a few. This is not a job for those who can only do bolt-on stuff, but it's doable.

http://users.adelphia.net/~dstudly/megasquirt1.htm

megaracerx

well...i think i'm gonna try it over the winter...how much wiring is involved?

i hope i can find a donor TPI car at a junk yard...

are there any other cars other than thirdgen that have the saem TPI system?





edit: can use my stock intake manifold?

Parrydise7

iTrader: (1)

I want to switch to tpi from a carb primarily to reduce the clutter under the hood. I want to clean up that maze of hoses and wires.

I've already got the S-D base plate so I can run the Vortec heads. All I need now is a new block (I want to replace the 305), rotating assembly, headers, ASM runners, assorted parts and I'm good to go.

Let's see now, okay, another $2500 and I'm probably there.

Zepher

iTrader: (1)

I spent less than $1000 to convert, that included the TPI setup, converting it to Speed Density, Eprom Programmer, Holley inline pump, rubber fuel lines, and some minor things.
I spent 9 months doing the swap since I also did Suspension/Chassis, wheels/Tires, rear end, and heads and cam.

I did the swap for aesthetics. Carb looks so dated and the TPI looks modern.
Car would probably have been faster with heads and cam with the carb.
I got a 14.1@99mph with the TPI.
Car ran a 14.9@92mph with the Carb setup and stock motor.
1986 Trans Am 305 LG4 5 Speed.

megaracerx

ok...stupid question.... what does "converting it to speed density" mean?

and is there a place i can by a NEW TPI setup, or do i have to go to a junk yard?

ChevelleFan

iTrader: (4)

I'm using a MegaSquirt, not a GM computer, so my wiring will be somewhat different. (ie-- homemade).



84-91 Corvettes. Good luck finding them in a boneyard.

Your stock carb intake? No. If you're asking this question, I strongly urge you to do some research and reading before you dive into something like this. This is not a job for beginners or those with little experience. Not trying to scare you from doing it, but be honest with yourself about your abilities and what you're willing to learn (or pay!) along the way.

-Dave

megaracerx

i know i'm new with engine work..so maybe i'll just tune the carb... buy some mods (ie. header, cat, heads)...and call it a day...

besides..i dont wanna throw too much money in the 305..there will be a 383 in the car one day.

vortec77

Hey Chevelle, im doing the carb to tpi swap myself, and when im done with it id like to go to a stealth ram or a ram jet as well. Do you know how much these units cost? and which unit would give more power? I think the stealth would but i like the way the Ram Jet looks.

ChevelleFan

iTrader: (4)

I have no idea which would give more power, although I'd probably guess the Stealth Ram. I really like the RamJet though, except the cost is a little on the high side.

A complete StealthRam manifold and fuel rails (add your own injectors, throttle body, wiring, computer) is around $500, I think. S10Wildside bought a 'Ramjet w/o Electronics' that is basically a complete manifold w/ injectors, throttle body, rails, injectors, and a distributor is like $1200. And you need Vortec heads and computer and wiring harness.

Decisions, decisions...

vortec77

I have vortec heads on my motor now with the sdpc vortec base manifold. Im just trying to get some ideas when im done with the swap then i can see what options i have for a different fuel injection system with the vortec heads or vortec bolt pattern.

contactpatch

For gas milage issues, people should consider a proper, and properly tuned, q-jet.
......................
no flame war intended here, I'm just curious.
'Why would anyone think that a TPI would produce more power
than a carb w/reasonable intake manifold...........
....from the factory, tpi had more power?, or some other reason?
........................
I have nothing against mpfi.
The problem with (this GM version of mpfi) tpi is: the diameter of the runners is too small, leading to chokeing effect at high rpm.
With carb, you can use many different manifolds.
....................
Note that , the word 'tuned' is misleading.
'longer than usual intake runners' woukld be more correct.
(note, long runners, is still useful, but)
In no way are the runners 'quarter wave resonant*',
that would require runners four feet long, at 5000rpm.
Long runners are useful, but IMO, not at the expence of
using a small cross-section.
.
*in the sense of single cylinder, note, some people claim
there is some type of 'multi pulse somethin...thats bs.

ChevelleFan

iTrader: (4)

Yeah, you can get some good mileage from a Q-Jet. However, see my note about gas on the hands and tuning adjustments for weather changes. Without having real proof, I'd still speculate a TPI will outperform a Q-Jet in terms of mileage and performance. Q-Jets make better mileage than a Holley. Holleys make better power than a Q-Jet. EFI doesn't have these kinds of limitations.

I never said TPI would make more power than a carb. I'm willing to bet it *will* make more low-mid range torque, though, which is great on the street.

If you want to see a truly LONG runner setup, go look at a 60s Chrysler cross-ram setup. www.allpar.com/mopar/sonoramic.html
I'll bet those runners are every bit of 18 inches long. But, with a large cross-section.

EFI isn't for everyone. I like playing around with cars, and after 15+ years of tuning carbs, I wanted to try something new. The TPI intake definitely has its limitations with regard to RPM, but that's merely a manifold selection issue -- much like a stock cast-iron 4bbl intake versus a Victor Jr. There's plenty of choices in EFI manifolds -- TPI, MiniRam, StealthRam, SuperRam, RamJet, LT1, converted Victor Jr, not to mention TBI. (consider a dual TBI setup that would mimic the old-school look of dual quads -- it's been done!)

-Dave

Zepher

iTrader: (1)

Speed Density is the 90-92 system for measuring incoming air using a MAP sensor. 85-89 uses a Mass Air Flow Sensor to calculate air volume intake.

To convert to Speed Density, you need a 730 Seres ECM and Memcal, an extra ECM connector, re-pin the engine harness, change the Knock Sensor, and add a MAP Sensor.
I chose Speed Density for 2 reasons, to get rid of the MAF and to run the SLP Dual Cold Air intake setup I bought.

If you really want TPI, get a used intake, base, and runners, new ECM, new Distributor, new Sensors, Painless Wiring TPI Engine Harness, and New Throttle Body. After spending the $1500 or so, tell us if you like it.

Personally, I'd rather put all that money into a motor and stick with a carb.
EFI can get expensive to maintain vs a carb.

Parrydise7

iTrader: (1)

Speed density is the preferred setup.

vortec77

Hey Zeph how much was the SLP dual CAI and did u feel a difference at all in power and got any PICS?? Thanks,

Zepher

iTrader: (1)

SLP intake was $299.
I don't know if there was a difference since I didn't have a stock intake to compare to.
My post above with the 2 pictures shows the SLP intake on the car.

86BirdSE

Has anyone priced a NEW carb lately? They're every bit as expensive as a used fuel injection system, and will still not reach the efficiency of a properly tuned squirt motor. Just my 2 cents.

However, if you're the type of person that farms out an oil change to Wal Mart, then (no offense intended) this conversion is not for you. Buy a fuel injected third gen and then learn form that.

RSFreak

Bwahahahaha! No doubt.

LEOVIZCARRA

Good evening friends, I need your help.
I do saw your carburetor conversion to TPI.
I have a EL CAMINO 1968 and I want to convert to TPI. the questions are:
1. - I have VORTEC heads, is complatible TPI manifold with these heads?
2.-is true that you need to pump in the tank, not working external fuel pump
3.- What was your gain in HP's and MPG?

I want to thank you for your help....


After converting to TPI,
[/quote]

vetteoz

iTrader: (13)

For Vortec heads and TPI you need this Vortec base $500
http://www.summitracing.com/parts/EDL-3817/

But taking into consideration buying that TPI base and the other required stock TPI pieces ,
you could buy this HSR EFI intake for $640 which has much better performance potential.
http://www.summitracing.com/parts/WND-7542/

the HSR needs these fuel rails
http://www.summitracing.com/parts/HLY-534-186/
( there are cheaper alternative rails )

Then you need a factory computer from a 86 - 92 TPI car and the wiring harness to suit

All you need is a high pressure EFI pump ; can be int or ext style

Parrydise7

iTrader: (1)

Okay, the last time I posted I was getting ready to convert from 305 carb and auto to 350 tpi and stick.

One guy asked me the same question: Why go from a carb to TPI? I guess the answer depends on what you want.

When I did my swap I wanted to use as many factory original parts as possible. So, in addition to the items noted in the post above, I replaced the gas tank. A gas tank for a carb'd vehicle will not work with tpi. Then there are the fuel return lines that have to go with it.

A factory wiring harness, modified to work, is probably the easiest way (easier than Painless), but even that will require modification.

As for power, I went from a 305 (rated at a whopping 155 hp, IIRC) to a 350 and roughly doubled the power. As for simply swapping a tpi for a carb, on the same engine, I would doubt there is much, if any, difference in power.

Keep in mind also, that if you start changing the parts on the engine (I added heads, a cam and headers) you will also need to tune the computer. For that, you will need a dyno and somebody with a laptop to plug into the aldl. Then, you will need to burn the chip.

Had some tuning issues so replaced the injectors with 30 lb injectors.

It may not seem like much, but this is definitely not a job for amateurs. If all you want is a tpi, for whatever reason, instead of a carb, I wouldn't bother.

djtricia

iTrader: (4)

Got complete tpi set ups with all sensors, wiring, ECU, etc. for either 305 or 350. $350.00 plus shipping. Pic posted in for sale forum showing everything.