im buyin a tpi its off of a 350 camaro i believe. and he says its coming with a maf. sensor and 19 pound injectors. what i need help with is what ecm to use. and maybe some good resources to get one and a eprom. also is a eprom the same as a memcal chip. and whats the difference between a maf sense and a map sensor. he also says its a l98 intake if that helps. thanks guys

 

Basically what ECM to use depends on which wiring harness you are going to use. The 1985 harness uses the 870 ECM along with a MAS module to handle the MAF functions (power/burnoff). The 1986-1989 harness uses the 165 ECM. The 870 ECM uses a bare PROM chip and the 165 uses a MEMCal/Calpack, which has the PROM chip and 2 calibration chips on it.
You are getting 19lb injectors...those were from a 305 engine. The 350's came with 24lb (1985) or 22lb (1986+). The manifold was the same from 305 to 350 but the F body heads changed in 1987, specifically the angle of the center 2 bolts changed and won't fit stock Corvette alumnium heads without some machine work done to the manifold.
The difference between MAF and MAP...about $460 (MAF costs more). The real difference is that the MAF sensor measures actual air flow going into an engine and a MAP sensor reports manifold vacuum which the ECM then uses with a look up table to add fuel...stock for stock they are about equal...on a modified engine the MAF is superior in that it is very tolerant of changes...the MAP is NOT and will require a custom prom to get it even close to running right.

 

the MAP is NOT and will require a custom prom to get it even close to running right. tis the problem im having after all my mods namely the super ram which has my map pulling its and my hair out.

 

The Camaro TPI fuel lines enter from the opposite side of the engine. What are you using if for? I have a 1227165 computer with an stock 88 350 TPI chip (no VATS) and a complete wiring harness for sale.

Art

 

pm me with pricing. i actually havent decided what to put it in. i just started building a new engine. but i do know im goin with camel hump heads and a and a 4 bolt main.

 

great thanks with the help now i keep hearing about the speed density. what exactly is that. and also what about the 1227730 ecm with a 90-92 harness will that work? with a custom prom for vats egr smog pump, injector size and fun working range. also should i get the 9th injector or is that to much of a hassle.

 

MAF and Speed Density (MAP) both are a way of measuring air flow, but they do it differently. The 730 ECM was used on the 90-92 speed density systems and those systems did not use the 9th injector.
What speed density does is measure manifold vacuum using the MAP sensor. The ECM takes that vacuum signal and uses a predetermined lookup table to determine fuel requirements. The problem is that the fuel tables were written for one specific engine combination. With the stock engine, X manifold vacuum = Y air flow through the engine, so the ECM sees X from the sensor, then checks the lookup table and it says for X MAP (vacuum) reading, add Z fuel. Now, do anything that changes the air flow of the engine (cam, manifold, heads, etc) and X manifold vacuum no longer equals Y airflow and the Z fuel added is no longer correct.
With a MAP system the lookup tables basically must be rewritten so they will be correct for the modified engine.

 

ok i got it stick with maf. and go with the 86-89 ecm and harness.

 

what sensors would i need to complete the tpi setup.

 

Temp sensor for the ECM (on intake manifold), temp sensor for the cold start injector (on intake manifold), MAT sensor (on plenum), knock sensor (in engine block), speed sensor (on speedo cable or trans), throttle position sensor (on throttle body), IAC/idle air control (on throttle body), MAF power relay (on harness), MAF burn-off relay (on harness), oxygen sensor (in exhaust headpipe), esc spark controller (on harness, if using TPI distributor with electronic advance). If you're trying to make it smog legal you'll need air injection port solenoid, air injection converter/divert solenoid, smog pump, EGR valve, EGR vacumn solenoid, EGR temp sensor, fuel vapor canister and solenoid, catalytic convertor, and all brackets/plumbing/lines/hoses. I think I have all the relays and most sensors in my stash. You should have most of the major sensors on the TPI assembly you got. It would be nice if you could get this stuff from the donar car, especially if trying to make it smog legal. If you can read the numbers on the injector body I can tell you if you have 305 or 350 injectors. I have both chip sets for the ECM.

Art

 

art,

it looks like you have everything i need. lets work a deal out. my email is siccmademuzak@aol.com

 

When you get the parts....eliminate the 9th injector (cold start valve) by blocking off the hole in the runner, plugging the hole in the intake where the thermotime switch goes and cap off the fuel tap on the back of the fuel rail...then get a memcal for a 1989 350 TPI. 89's didn't use the 9th injector, they had startup enrichment routines in the prom code.

 

whats the purpose of eliminating the 9th injecter ?

 

One less thing to have break and have to troubleshoot. They are known for leaking vacuum where they go into the runner (pain to get it seated properly sometimes), leaking fuel where it hooks to the fuel rail.