Hello,

I wasn't ready to tackle this project just yet until I found a TPI unit with the PCM and wiring for what I think is a good price. I have an 82 Corvette with the Cross Fire Injection system and was hoping to upgrade. I have plans after my T5 Conversion to build an engine for the car. My hopes are to achieve 350-375HP out of a mild SB350 build. From what I know the TPI engines are great for torque and low RPM power. While I really don't know all that much about the LT1 engine (1994-1996 Impala) I know that the fuel system is excellent and that it too has great power potential. This project can go in any of the following directions. Buy the TPI and bolt it onto my rebuild (originally cross-fire injection) engine (which is the first choice if possible,... cheapest). Rebuild a TPI engine out of a Camaro or TA. Buy and rebuild an LT1. Currently I am more interested in finding out information about the TPI system. Can the TPI be bolted to my 82 350 engine? What is the extent of the wiring of the TPI system? Is the TPI a good system to use over the LT1's system?

Thanks,

Dan

 

If your gonna spend the money on a FI system go with
the LS1. TPI, LT1, and LS1 are not cheap swaps.So if
your going to do one. do the best thats out there now.

 

I agree with Meg, these daze, may as well do the whole thing and do it right, back ten years ago when I did my TPI, it was a hot lick, but today, no..it's severely dated....

GENE

 

i agree with the others but too a point,i really love the tpi,only reason im taking itout is cause i get bored with stuff,so im switching to ls1,but i love the way the motor runs.Tons of torque especially with the zz4 cam and 700r4 trans.I used a factory harness and modified it to work,if you canget a aftermarket harness cheap go that route.

 

I would just swap to TPI on your stock bottom end. You already have the right fuel tank, just swap to a TPI pump. I have TPI and I love it. If you do a search on my user name and "TPI" you will find a guide of sorts to installing it on a C3. Since you have an 82 you are already half way there.

 

Pat/Mark, don't get me rong, I like my engine and all, but IF I was to change anything, say a rod went through the block or some other disaster befall that engine, it's time for an update, like you are doing Pat, as I recall.....
I have the TPIS ZZ9 cam in it, as it was the hot lick at the time, and it's been fine, super pleasure to drive,....as it is in reality world, I need do something about my headlight project, or find another way to mount the lo profile bulbs and fortget the operating mode entirely, save weight and complexity....

besides Chris, 69 my way has moved south for job boost, and so is no longer easy to help me.....

GENE

 

I just said I would add TPI to his bottom end if I was in his shoes. If a rod eats the block I'd do an LS engine. But, Scoggin-Dickey claims a stock L98 bottom end with Vortec heads and TPI will do 350 HP. The stock Cross-Fire bottom end might not get there, think you'd need the roller cam. As far as an easy install and moneywise from where he is, TPI is easier because it is basically an intake swap and some wiring. An LT1 would be next easiest/cheapest, but you'd need all new accessories and an engine removal/installation. LS engine can of course be done, but it is the hardest and most expensive retrofit of any FI swap. It all depends on how much work, money, and time he wants to spend.

 

Hey Mark,

I think you have the right Idea. When I do the engine,... which I decided will be done in June, just because I know I will have the money then; My intent is to try and spend about $1200-1500 which CAN be done. My friend is going to do all the machine work and as previously stated I intend on doing a mild build. 350-400HP.
Speedpros, Nodular Iron polished crank, polished heads with minor port work, hydraulic cam,... possibly solid roller depending on my mood and funds at the time. And the bolt on's will pretty much be GM stock stuff - ex water pump. I know Carb'd small blocks pretty well, but know nothing about fuel injection. I just figured I would do something a little more different and a little more modern. LS1 is out of the question. Their like $2000 just for a used high mile engine, and I would want to rebuild it. Not looking to spend $4000. If I can find a $500 used LT1 out of a police car I could consider rebuilding that.

What I was really interested in know is how the TPI unit would bolt up to my already existing 82 SBC Crossfire. If I could just switch units for now and wire it up,... thats a good start. But I am also interested in finding out about ease of wiring before I jump in and start ripping out wires and the PCM. And just wanted to make sure the darwn thing actually BOLTS up...

Sorry if I wasn't clear guys,

Thanks for the input,

Dan

 

Your crossfire harness wont work,you have to use the harness according the type of tpi you use,as in mass air flow or speed density,it just depends on what year the tpi is from.The intake will bolt up depending on what you get it from,i think the vette intakes will bolt right up the 87- and up camaros and trans ams you have to elongate the center intake holes a bit for the bolts to line up,which is what i did.stay away from 85 tpi's go with 1986 and up.Speed density wil be easier for you so you dont have to worry about putting the mass air flow sensor on and then an air filter,an air filter can go right on the end of the throttle body if need be with speed density.Hope that helps.Also the crossfire uses a low pressure pump the tpi needs about 42lbs to run .So youll have to swap pumps in your tank.

 

Excellent,

Thats what I needed to know,... just one more question. I read that speed density calculates A/F ratio based on a more mathematical formula, while Mass Air flow, calculates based on what the O2 Sensor reads and what the mass of the air charge coming into the intake. Mass Air Flow I read is better for performance,...

True or False

Dan

 

I'm going all out and putting a LS1 in my 76' Everything I've read it's just awesome i.e. power, torque, responsiveness, aluminum block, less vibration and quite...

 

They both use O2 sensors as does your cross-fire. Mass air flow uses a sensor to measure the amount of air entering the throttle body. Speed density uses a manifold pressure sensor to help determine airflow. Then they both use throttle position and O2 readings to determine how much fuel to inject.

Speed density does not have a MAF sensor to impede airflow and is easier to plumb and wire. It is not as forgiving on engine changes so if you change cams or make other power additions you may need a new PROM calibration. Calibrators are getting cheaper, but to be honest I have not gotten involved with that. Both my TPIs are bone stock as were all the retrofits I have done. Mass air flow is more forgiving of engine changes.

See http://forums.corvetteforum.com/show...tpi&forum_id=3

 

That was definately my first choice. Stock the engines run really efficient, are very powerful, have a race car style tone I love, but the cost could choke a horse. For what I would pay for a rebuilt LS1 I can buy two TPI's, thats the only reason why I am leaning towards TPI. Buy hey,... if you've got the funds go for it. My friends got a new GTO and believe me you wont regret putting that engine in any car.

Thanks Mark,

Thats something to consider. When I do rebuild the engine I will more then likely use aftermarket parts.... nothing too crazy but in any event I will change to a higher lift cam, maybe with a slightly higher duration also.

 

What I meant was that the computer software, knowledge, and hardware to burn your own PROMs is getting more available. All the PROMs I have used have been for stone stock speed-density setups, so I have never needed a custom fuel calibration. Speed and Performance (and others) can take your info and burn a custom PROM for you. They take lots of info on your combo and burn a PROM just for your situation. They can also turn off VATS, EGR, and any other stuff you dont want.

One final thing to tell you-I believe your speed sensor on the speedometer is 2000 pulses/mile (ppm). That is what you need for mass-air. If you decide to go speed density you will need a 4000 ppm external sensor which is not compatible with your cruise control. If you want cruise control with 4000ppm it is an easy upgrade to cruise from 90s GM cars and trucks-no vacuum, just wires.