TPI parts worth swapping?

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mcarlo86

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I saw this ad the other day. I was curious if the TPI parts would be worth anything? What would need to be done to put a TPI system from a 305 on a 350? Are the injectors the same? Different tune? I would think the serpentine belt system would have some value if anything. I always liked the looks of the TPI and if I remember correctly, they did make pretty decent torque, so I thought that could be a good setup in a pickup/suburban. Thoughts?
 

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Yes, a broad torque curve but pretty much limited above 4500 RPM. Would probably work well in a truck application. You would need a stand alone controller to run it I believe. No basic difference in a 305 or 350 application other than injectors if I remember correctly.

I have a spare lower intake manifold and upper plenum here that I bought to hand port. I have maybe $150 in the both of them. Don't over pay for the full system. There are still a lot of them out there. You should be able to score everything, manifold, runners, throttle body, fuel rails, injectors, etc. for under $400 in perfect condition.
 

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I have a setup that I'm going to run on a vortec headed 383 with a holley terminator. Hoping for a nice big flat torque curve out of it...

I gave about 150 for the whole thing. Unfortunately the vortec lower was $400...
 

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I'd say that'd be a cool setup to swap on an existing tbi 350 truck. Most of them don't have anymore cam left in them after 4500 anyway.
 

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That one is an '87. It looks to be complete.

I really like TPI. It's almost like big block torque in a small block. Almost. I never understood why GM didn't run it in trucks, as an option above TBI. With all stock parts, they do indeed peter out by 5k, but they can be made to handle more cubic inches and more rpm.
 

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24 years ago was my first EFI TPI swap...work great nice little set up...and today is cheap ;)
 

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mcarlo86

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That one is an '87. It looks to be complete.

I really like TPI. It's almost like big block torque in a small block. Almost. I never understood why GM didn't run it in trucks, as an option above TBI. With all stock parts, they do indeed peter out by 5k, but they can be made to handle more cubic inches and more rpm.
So '87 would have the 9th injector, correct? I was reading somewhere that TPI setups from '90-92 are the most desirable. Is there anything to watch out for with this '87 setup?
 

bucket

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So '87 would have the 9th injector, correct? I was reading somewhere that TPI setups from '90-92 are the most desirable. Is there anything to watch out for with this '87 setup?

Yes, it has the 9th injector. Not a big deal and if you come across higher flow runners that are without the injector, tuning can replace the cold start enrichment. '88 was the last year for the 9th injector. '87 was the first year for the splayed center intake bolts. It was also the last year for v-belts, but the alternator bracket was different from previous years because it was designed for the cs130 alternator. Also, '87 was the first year for that smog pump divertor setup.

I personally do not have a year preference. You just need to be aware of the differences for swapping and modifications. The '85-'89 maf system is a little more forgiving for variances. '89 is the start of the VATS security system. '90-'92 MAP systems are capable of more airflow (and no old/aftermarket MAF gremlins) but get upset easier from modification.

I've had several TPI Camaros, all of them MAF systems. No complaints about any of them. I currently have an '86 350 with an old Crane CompuCam, Edelbrock RPM aluminum heads, 24lb injectors, headers and a nearly 100% stock TPI intake. The grunt that thing makes is awesome. I haven't updated the setup in nearly 20 years. What I'd really like to do now is swap the base and runners to an old Accel or SLP setup (or swap the whole deal for a First intake) and run a cam sensor to run a Holley Terminator system and go to a distributorless ignition. It basically would be most of the LS swap benefits, but the period correct look and badassness of the original TPI.
 

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What I'd really like to do now is swap the base and runners to an old Accel or SLP setup (or swap the whole deal for a First intake) and run a cam sensor to run a Holley Terminator system and go to a distributorless ignition. It basically would be most of the LS swap benefits, but the period correct look and badassness of the original TPI.
My eventual plan with mine is to go to LS coils using the Dual Sync distributor. It will also be sequential injection instead of batch fire like the oe system.

There are lots of benefits to a modern control and holley has a harness to run a tpi injection with a terminator so it really doesn't matter if you don't get the factory harness or pcm with them anymore. Plus the Holey will be much easier to tune an tolerable for nicer sounding cams.
 

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My eventual plan with mine is to go to LS coils using the Dual Sync distributor. It will also be sequential injection instead of batch fire like the oe system.

There are lots of benefits to a modern control and holley has a harness to run a tpi injection with a terminator so it really doesn't matter if you don't get the factory harness or pcm with them anymore. Plus the Holey will be much easier to tune an tolerable for nicer sounding cams.

My specific plan would be to use an EFI Connection cam sensor and timing cover setup, along with the distributor stub to drive the oil pump. Then mound the LS coils where the distributor cap used to be, and use a Terminator setup for an early style LS. I have no business trying to tune it myself. I was told that the Holley should self learn ok, then I could easily take it to someone that has tuning experience, if it's needed.
 

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My specific plan would be to use an EFI Connection cam sensor and timing cover setup, along with the distributor stub to drive the oil pump. Then mound the LS coils where the distributor cap used to be, and use a Terminator setup for an early style LS. I have no business trying to tune it myself. I was told that the Holley should self learn ok, then I could easily take it to someone that has tuning experience, if it's needed.
The dual sync distributor has a cam and crank sensor in it. You can get a flat cap for it when using it only for the sensors. No need to change the timing cover an add the sensor there with it! I honestly want the coils on the VC so people go wtf?

The self tuning is decent but it's only for the fuel trims. You need to manually set your desired afr, timing, accel enrichment, cold starts, etc. I don't like how they advertise them because people think it will "learn" everything on its own an you shouldn't have to touch it. People get suckered in by that an have high expectations an then are pissed that they have to adjust things. I've about stopped working on Snipers because of people's attitudes and shoddy installs....
 

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