i just bought an 85 Trans Am with a good running 305 TPI. it has a b&m shift kit and a jet air foil and i was wondering if there is anything that is really cheap or free even that might make a difference in throttle response or power. im all new to the TPI system so any tips on anything at all with this system are helpful

 

The '85 TPI was a 1 year wonder system. That particular ECM (870) and related setup was used only in 1985 and thus has very limited support. The good news is that you can swap to a newer ECM (165) which has abundant support for programming and modification. The process is detailed here http://www.eecis.udel.edu/~davis/z28/ecm_swap/ I did this swap on my 85 IROC, it took about 4 hours and cost me $50 for a 165 ECM with a Calpack for an F body already in it. $28 for 2 relays (they replace the $800 MAS module) and $20 for the relay sockets with 8" of wiring pigtails (get these at Pepboys).
If you decide to do this swap drop me a PM here and I'll give you some details on doing a couple things differently than in that article, they'll save you a few $$ and some frustration.

 

does this require any soldering in the ecm and also will i feel a noticeable difference from this

 

No solidering "required" at all, but I solidered my splices instead of using the crimp on splices. No modification to the ECM is done at all.
I did the swap because I had installed a very healthy 350 in place of the 305, so my relults were dramatic. If you swap and use the $6E code you will notice a difference in driveability, throttle response, plus, if you mod the engine it will be easier to burn chips for it (more avialable info and bin files).

 

When doing the swap wouldn't you have to program a new eprom in order for it to run right.

 

That depends on what memcal you get to use with it. If you are running a stock engine you could just order a stock memcal for your size/type engine for any of the years that the 165 ECM covers (86-89), of course if you use an 89 memcal you will need to disable VATS on the chip since your car doean't have it.

 

In the tech articles section of this site there is an article about a throttle body coolant bypass that many people do and it costs next to nothing. Many also remove the screens from their mass air flow sensor.(free). Also any weight you can remove like A/C and such is added power. Also a good tune up can make a world of difference and is standard if you just bought the car.

 

oops

 

People have already mentioned the bad thing about the 85 TPI system. On the brighter side the 85s came with a somewhat decent cam. I somewhat surprised you would first want to address throttle response after driving a TBI car. I think at last count I have owned 5 85s and it seems that these were somewhat fast from the factory. There are a couple little things to increase throttle response that dont cost anything, if you havent already, advance the timing a few degrees. Another thing you could do is increase the TPS voltage to somewhere around .62 rather than the stock .54 setting. I forget what the magic number is but if you increase it too much it will give a check engine light. These things will help out a little!
If you want to do a little more and be cheap, perhaps a K&N filter and try to get more air flowing through the stock air filter housing by either cutting a window or drilling holes in it and shim the fuel pressure regulator with a quarter to increase the pressure a little, this however might cost you the price of a set of new upper plenum to runner gaskets.
Have fun!

 

thanks i was planning on porting the plenum also. the throttle body coolant bypass is going to be soon too. when i get my other car done and this one painted i will order headers and an exhaust. how would i advance the timing on the 305 tpi. that is on e thing i am not familiar with and is there a tech article on shimming the fuel pressure regulator. it already has a new tune up and a k&n air filter and i also cut the holes in the air canister but i plan on making a cold air intake soon. what are the most effective mods for the money on a TPI you said that they have a nice cam so that isnt something to worry about right away.

 

Shimming the FPR is the "ghetto" way around. An accel adjustable FPR isn't expensive, go that route and get a pressure guage for it.
Advancing the timing isn't advised, the computer is going off of its programing which says the timing is set at 6* BTDC, change that and all if its calculations for spark are void. 6* is where they run best, especially since the programming is set for that.

Do yourself a favor, do the headers and exhaust BEFORE painting. If you do them after you'll be real upset if you scratch that new paint putting them in.