Sinful One RS

Hi all,

I need help and hope someone can help me. I see that Kevin usually gives good advice and I hope he can help (or anyone!).

Here are the mods to my engine that I'm going to put into my 91 Camaro RS (currently it is a COMPLETELY stock 305 TBI).

It's a 350 bored 30 over, with a Performer RPM cam, Performer RPM heads w/64cc chambers, flat top pistons, running around 10.5 to 1 compression.

Now, I want to put a TPI unit on this motor and drop it in my RS. However, I'll have to get a TPI out of a junkyard. Considering the stock PROM and computer and wiring in my car, which TPI should I get? What year(s) car should I look for to pull the TPI out of? I'm confused about the MAF and SD units and don't really know the difference. However, my motor should make about 425-450 HP (not kidding or dreaming) with the mods I've done. So, I need to know which TPI would be best to get/use so that there won't be any problems when I drop it in!

I really appreciate any help with this. I'm even somewhat confused on what chip to get as well. Plus, I hear people talking about "burning" their own chips for their mods. How do you do that? What would I need to buy/rent to burn a chip for my mods and I don't even know all of what the PROM controls?

Sorry folks, I'm use to carburated engines and not all this tech stuff, but I'd like to get into the 2000's and stay with the computer.

Please help. Even if you have to email me the answer because it's too much to post. Please...I don't want to buy the wrong thing and/or don't buy/get everything I need!!!

Help....<looking pathetic>

Cya on the streets

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Sinful One RS
91 Camaro RS w/305 TBI
3.23 posi w/disc brakes
145 speedo
Z-28 Fog Lights & grille
Sinful One RS's Domain

IROCZTWENTYGR8

iTrader: (1)

Here is the difference. Speed Density, uses a Manifold Absolute Pressure sensor. The MAP is different from the MAF in that it measures engine load, using manifold vacuum instead of intake air mass. The Speed Density system has the advantages of reliability, and zero intake restriction, but the MAP sensor is a far more limited sensor than the MAF, and less flexible. You can modify your MAF engine to the hilt, and the MAF will keep happily reporting air mass, temperature, humidity, and pressure to the ECM without a complaint. The MAP sensor on the other hand delivers only intake manifold vacuum values, and the ECM must rely on fuel maps stored in memory to properly calibrate engine function based on the MAP readings, along with the input from other sensors. What this means is that major engine modifications on speed density systems generally require a revised PROM with the new fuel maps in memory.



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Looking for:

87 IROC-Z L98
84 TRANS AM H.O.

3gc

There's an article on this site about burning your own PROMs.

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3rd Generation Camaros

Sinful One RS

IROCZTWENTYGR8,

So, basically I should go with the earlier (pre-90) MAF unit. Now, I know I'll need to pull the ECM, whole wiring harness, along with the TPI (complete to manifold). Is there anything else that would be a problem or that I would need to bolt this onto my 1991 RS 305 TBI? I might be going out to get the TPI and stuff tomorrow or Sunday, but I need to know the type of vehicle(s) that I can get the parts out of. If now I know I have to look for a Camaro/Firebird from 88-89, right? Isn't that the MAF years? I know from 90-92 is the MAP years, or at least so I understand.

I was going to buy the TPI now and bolt it onto my 305 and when I go to drop in the 350 (next March or so) then I would change to a custom PROM and change the injectors and such. I just don't want to buy a TPI set up and find out that when I put the highly (450 hp) modified engine in, that it won't work at all.

I appreciate yours and anyone else's help...

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Sinful One RS
91 Camaro RS w/305 TBI
3.23 posi w/disc brakes
145 speedo
Z-28 Fog Lights & grille
Sinful One RS's Domain

Sinful One RS

3gc,

Thanks, I'll check out that article...I appreciate the tip!

Cya on the streets...

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Sinful One RS
91 Camaro RS w/305 TBI
3.23 posi w/disc brakes
145 speedo
Z-28 Fog Lights & grille
Sinful One RS's Domain

BadSS

Sinfull,, Don't get the early edition MAF, if you're dead set on a TPI system try and get one from an 89 if possible - number of reasons, one no cold start injector and most of the modified "free" BINs are based on the 89 code.

I've got about a 350 - 360 horse 355 with the modified 86 TPI running 24# Ford injectors,,, runs like a scalded dog,, idles terrible and I can't seem to be able to get any "in depth type answers,, maybe it's the way I ask the question,, I don't know. Maybe the MAF guys are just not out there.

$0.02 from an old man,,, if I were doing a fuel injection car again - not worried about the tree huggers,, starting from scratch,,, I'd go with the Pro-Flo Edelbrock or the MPI Accel or Holley,, so I could tune the freaking thing myself. By the time you send the money to get a TPI system to support even 400 horses,, you'll hit the $2000 mark - Used TPI w/computer and harness $350, Intake $375+, Runners $210+, 52+ T/B - $300+, injectors $220+, AFPR $65+, MAF - $250 (gotta count it,, cause if your luck is like mine,, it'll be bad),, other related sensors $100,, custom chip calibration $300+ - what's that?? $2,170+++,,, hmmmmmmm MPI Holley is like $1,895 - Just a thought,,, I won't say I'll never build another EFI "weekender",,, it just won't be another TPI!!!!! Only reason I'm struggling with this set up is I got a good deal on the car with the TPI and a lot of the parts that's in the sig,, and at this point have too much time and $$ to not finish the TPI project,, plus I must admit,,, the midrange pull on this TPI is tough!!!!!!

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86 IROC - 9.8:1 - 355, TFS twisted wedge heads, 218/228-110, fully ported GM base and plenum, SLP runners, 52mm BBK, 24# SVO, 1 5/8" Headman headers, 3" Dyno-max, TH350, B&M Megashifter, 245/45ZR17s on 212 Eagles

IROCZTWENTYGR8

iTrader: (1)

MAFs run from 85 to 89, but like SS said, try to get 1 around 89.

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Looking for:

87 IROC-Z L98
84 TRANS AM H.O.

Blade

Or to make things A LOT simpler get a MAP system from 90-92. The ECM is more advanced, chips can be burned easily to compensate for whatever mods you do and so on... Don't believe the bull**** about the MAF system being able to measure more accurately. I have a healthy 350 in mine and I still pull 13s with a stock chip in my SD system. A MAF car will be right there next to me in a 1/4 run not ahead.

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92 Z28 L98 350
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Ported and polished heads, ported stock TPI base, ported plenum, Comp Cams XR270HR-10 cam (lift .495/.502 duration 218/224 lobe separation 110), Edelbrock TES headers, LT4 valve springs, Crane AFPR, Flowmaster catback with LT1 style tips, MSD coil & wires...

"Take that auto, drop it in first, hold the brakes, stomp the gas and grin from ear to ear! :-)

IROCZTWENTYGR8

iTrader: (1)

"The Speed Density system has the advantages of reliability, and zero intake restriction, but the MAP sensor is a far more limited sensor than the MAF, and less flexible. You can modify your MAF engine to the hilt, and the MAF will keep happily reporting air mass, temperature, humidity, and pressure to the ECM without a complaint. The MAP sensor on the other hand delivers only intake manifold vacuum values, and the ECM must rely on fuel maps stored in memory to properly calibrate engine function based on the MAP readings, along with the input from other sensors. What this means is that major engine modifications on speed density systems generally require a revised PROM with the new fuel maps in memory."

For what he wants, which is a heavily modded 350, the MAF is better. Also, for a heavily modded 350, u might want to look into buying a Wells MAF, instead of modding the stock 1, the Wells flows 750 SCFM, compared to the stocks 544 SCFM. The diameter of the sensor is also 78mm compared to the OEM's 70mm. For the Wells MAF, Take This Link: http://www.wdautoparts.com/cgi-bin/sslshop/ssl_shop.cgi
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Looking for:

87 IROC-Z L98
84 TRANS AM H.O.

[This message has been edited by IROCZTWENTYGR8 (edited October 14, 2000).]

[This message has been edited by IROCZTWENTYGR8 (edited October 14, 2000).]

Sinful One RS

I thank everyone for their input. I guess I'll just have to make up my mind on which one to get and what is available for me to get as well. Since I would be changing the ECM, wiring and adding the TPI anyway, it really doesn't matter which system I go to, even though my car is a 1991. Only because I have a TBI and I looked in the book and found out that it is TOTALLY different chip and computer, so it's going to be ripped out anyway.

As for my mods, I was thinking of going with the SD because it seemed easy enough to just change the PROM for my fuel maps, however, I wouldn't know what to set it at or even how to tell someone else how to set the fuel maps in a PROM for it to work right and I don't have the money to keep having PROMS burned because I put one in and the car ends up running lean and all that. Plus, I'm building an OLDER block (pre 87), so it won't be the roller cam and all that. I'm going to be putting in a pretty healthy cam with a lope and if the MAP only reads off the vacuum pressure in the manifold, that will be a problem at idle, no??? I see that it would probably read it way low and that would also cause problems. I know I'm not putting a motor in that can run 10's, but I would like to get into the low 13's or maybe high 12's if possible (I will be driving this daily). I just raced the car last night and it ran a 16.30's. I just about died. I know that it is a 305 TBI w/126,000 miles on it, so I really want to get this set up right for the 350.

As for the MAF system, I see it as a possibility of a step backwards because the computer would be older (going to try and find an 89 per everyone's input) and such. Plus, then everyone says there are restrictions with the MAF. So, it's like a toss up either way I go. I'm not saying I expect something to bolt on and be perfect, heck even carbs aren't like that! hehehehe However, most people seem to believe that the MAF system would accept my mods more evenly, plus, all I would have to do is mod or get a new MAF (per the last post) unit. I know it's expensive, but in the long run would probably be cheaper than buying more PROMS.

One other question (I know you all are probably getting sick of me by now and I'm really sorry), if I go with the 89 MAF ECM, will that be a problem with my current car? Meaning will the VATS (PASS key security) work? Will the VSS (speedometer) work? Are there any other issues I should think or be concerned about because I'll be changing the WHOLE ECM?

I'm planning on going out now and looking, but before I buy it or take it off the car it's on to buy it should there be anything else I should be concerned about? Plus, I'm planning on taking the wiring out of the car I'm pulling the TPI from (if possible), should I just be getting the wiring harness for the engine or what? I don't know what all hooks to the ECM. I looked at my car and the wiring that came out of the body near the ECM (under the dash) and I forgot about the A/C hook up and the windshield wiper hook up, etc. What happens if the "new" ECM doesn't have a/c in that car. Can I still run my a/c or what?

Plus, does it matter if I get the TPI from a Camaro or Firebird? or are they and the wiring the same????

Again, thank you all for your help and if I can help anyone as much as you all have helped me I definitely will!!!!

Cya all later...

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Sinful One RS
91 Camaro RS w/305 TBI
3.23 posi w/disc brakes
145 speedo
Z-28 Fog Lights & grille
Sinful One RS's Domain

Kevin91Z

iTrader: (1)

If I am the Kevin you are refering to, thanks for the compliment.

This a lot of information to type out. Its really something that needs to be explained in person. First of all, you are going to have to be extremely lucky to find an 89-92 TPI setup in a junkyard. You'll have to go aftermarket, or to a specialy yard. And you'll pay bank for it. Also, if you have emissions testing in your state like CA does, your only choice is a 91-92 TPI system (90 is the same and they wont notice), because you cant put an older EFI in a newer car.
Long-runner TPI will not support 400-450 HP, but you will sure get 450 TQ out of it easily. If you're looking for that much HP, go with a SuperRam or MiniRam intake. Accel makes a complete changeover kit to convert your carb system over to EFI, but it is marketed towards older cars and costs about $3000. I dont believe it would be that difficult to convert the wire harness over to work with smog setups. Also, your computer doesnt care if your AC is hooked up or not. The TPI is the same, Camaro or Firebird, but the Firebird has the battery on the driver's side, so some of the hookups will be different.
In my opinion, if you really want this kind of power from a TPI setup, sell your car and buy an 89-92 TPI car and modify that. You will come out far ahead in the long run.

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1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.25 @ 107.18 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Webmaster: SoCal F-Bodies
-=ICON Motorsports=-

Sinful One RS

Well I was a day late and a dollar short. I went to a junkyard here yesterday and found an 89 Firebird with TPI, but someone was already working on it (taking out the TPI). I live in MD and it seems like there are NO junkyard/salvage yards here where you take out the parts yourself. All of them seem to be where they take it out for me. (I've only found 2!)

I also checked on ebay and found a couple of units there running about $510-$620 for the complete TPI and wiring. I just not sure what to do yet. MD does have an emissions test, but they don't look under your hood or anything. They just check under the car to see if the converter is there and if you have a gas cap on the car. Then they test the emissions. That's it. I'm not too worried about that. Plus, they way they acted when I last went, I doubt they would know the difference in TPI's.

I would like to sell the car and go with a TPI car, but I don't have the extra money right now to afford the TPI car. Plus, I wouldn't even know what to sell my car at. Plus, I drive it every day, so that's not quite an option.

Anyway, I appreciate the info. Hopefully I can keep checking around MD and lower PA for junkyards that let you pick the parts yourself. That's about all I can hope for. I would like to take it out of the car myself so that I can see how everything was hooked up. Otherwise (besides my service manual) I'm doing it blind when I put it in.

Thanks again for the info from everyone. I'll let you know how my endeavor goes as soon as I find out! Hehehehe

Cya all on the streets...

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Sinful One RS
91 Camaro RS w/305 TBI
3.23 posi w/disc brakes
145 speedo
Z-28 Fog Lights & grille
Pathetic 16.30 in the 1/4
~~~~~~~~~~~~~~~~~~~~~~~~~
Sinful One RS's Domain

Kevin91Z

iTrader: (1)

This is a big job for someone who's "doing it blind" as you say. Your car will be down for a week while you swap. And its going to cost a lot of money, probably very close to what you could get a whole TPI car for. Are you sure?

RP1987GTA

going from TBI to TPI for even an experianced wrench requires alot of tech knowledge.....you can't imagine what you will run into......if this was a project car you didn't drive often then letting it sit for a month while you get it drivable would be cool.But you use it as primary trans.....The motor you built for this would be much happier with a good carb setup...a stock tpi is never gonna do 400 hp and at 5000 RPM that motor is gonna look up at the induction setup and think...an ELEPHANT SAT ON IT

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87GTA,350,Auto,MAF screens removed,195 thermostat,cold start injector UNPLUGED,K&N,modified air intake,ADSchip,3:73s,3inch cat back Flowmaster single outlet,TPS.54,Bosch Plat plugs,base timing 6BTDC,22 MPG and runs like a bear,Bilstiens in the rear....,don't let yer meat loaf

[This message has been edited by RP1987GTA (edited October 16, 2000).]

Sinful One RS

<banging my head against a wall>

I just don't know what to do now. I do have another form of transportation (kind of). My room mate said he'd let me borrow his car while I did the mods, so I'm not too worried about that. I'm actually sure I'll be fine doing the change over. I would love to go with a carb (much easier for me to put in a vac. adv. dist. and a carb), but then if MD inspects it (even if it passes emissions) then I'll flunk (even though my next emissions test isn't until 5/02) and then I'll REALLY be screwed.

I appreciate everyone's help. Maybe I'll just get a TPI system for my 305 for now and then decide later what to do when the 350 is done. Then again, maybe I should just build the 350 and leave the 305 alone totally with the TBI for now.

I'm just afraid to pull the computer from the car altogether. Not really because of emissions, but because I'm afraid of effecting things on the car and then they don't work. I can't really post here about getting info on what would happen if I tried to go to a "just carb" engine in my car because this is a TPI board and I don't want to tick people off. However, you all have given me so much help and I really, REALLY do appreciate that!!!

Well, I guess I'll just have to go with the flow (so to speak) and see what happens.

Thanks again to everyone for their help, input and especially putting up with my 1 million questions!

Cya all on the streets....

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Sinful One RS
91 Camaro RS w/305 TBI
3.23 posi w/disc brakes
145 speedo
Z-28 Fog Lights & grille
Pathetic 16.30 in the 1/4
~~~~~~~~~~~~~~~~~~~~~~~~~
Sinful One RS's Domain