Before I begin, I want to state the fact that I have spent alot of time searching. I've learned alot of what I need to know, but a few things aren't 100% clear.

Things I know for a fact I'll need
Fuel pump
ECM with matching knock sensor
Throttle body w/ injectors


My biggest concern:
I'll be mainly looking for my ECM in late 80's - early 90's (pre-vortec) trucks
My question is, is there an ECM I need to look for, with a particular serial number?
Are they all plug and play with my harness?
Where is the best place to get pin-out charts if need be?

I'm looking for the most affordable options, due to being low on cash and my 305 being on its last leg.

I've already found an engine from an 89 350 TPI car, just need to save a couple bucks and go pick it up.

Any help is really appreciated,
Thanks

 

Do you not have an ECU in the car? 8746? 1988 Camaro I see...

 

I do have one in the car, how ever, correct me if I'm wrong but I need one from a 350 so I'm not running lean

 

Please read this https://www.thirdgen.org/forums/tbi/...-350-swap.html

For fueling you only need the injectors and chip (insert into your ECM) from the 350.

If you do not plan on tuning in the near future, the stock fuel pump should be ok.

 

I'm not sure if this is the correct venue to ask this question, but here goes anyway: I have an '88 305 TBI 5 spd car and I am considering moving up to a 350 engine. I would like to keep it TBI. I assume that the Edelbrock Perfomer TBI Intake will work. I know that I need to upgrade the chip, knock sensor and fuel injectors to 350 specs. I just recently installed 081 heads from an '87 TPI car on my 305 engine. I had them reworked. my question is can I use these heads on the 350 block? I know they will bolt up but will they work ok? My other concern is addressing any ECM issues with putting a T5 5 spd tranny behing the 350 since this is not a stock configuration. Let me know. Thanks.

 

Everything that is on your 305 now will swap over to the 350 (minus head gaskets). Bolting stuff up will be the least challenging thing you will face. You will have to tune the combo via chip burning. Time to start reading up on EBL.

 

Just to clarify... EBL is not necessary but highly recommended especially for newcomers to the tuning experience. i started with 7747(very similar to 8746) and through use of Tunerpro(free) or TunerCat(small cost) to modify my .bin on my chips. winALDL or TunerProRT and a ALDL cable($40) to datalog sensor readings a handfull of chips and a used laptop(free due to bad battery) I was off and running. see Craig Moates for minimal cost equitment to get started if you are interested.

 

Thom, I've read that post and many others pertaining to the subject. But I wasn't a 100% on it. I'm down to one last question. Which is, when I'm looking for the chip(via truck or caprice) what are the specifics that I have to look for? Besides making sure its an L05.

Other than that little speed bump I'm set.

 

Thanks for your responses Shifty and Ronny. Sothe L05 350 referred to here - is that a roller hydraulic cam motor like my '88 305? I believe that this motor is in the 88 to 93 Caprices and trucks - does that sound right? Does anybody have the specs on the heads for that motor? I would like to compare them to those of the TPI 081 castings that I have. I assume that the chip burning you are talking about is due to putting my T5 tranny behind the 350 - is that right? Thanks again.

 

I would get the chip from a LO5 caprice, to get the car usable. No racing.

I do not have the LO5 chip # in my head, should check your ECM # first, as Ronny pointed out.

Second step will be to tune for best efficiency and power, at this point a TPI fuel pump or similar and a VRFPR will be needed, would be really easy to tune with EBL flash.

L98's came with 083 head castings and 113 (corvette) if I remember correct.

Not sure how much power a L98 can make with the LO3 exhaust.


EDIT: if manual transmission, there's probably no way around a custom tune. I do not know of a factory 350TBI with manual transmission.

 

Your choice of chip depends on whether you use a 7747(truck ECU) or 8746(passanger vehicle). 8746 only supports IAT. You would chose same CID as your vehicle (unless you want to modify the chip) same tranny(manual or auto unless you modify chip) and as close on gears(same mod). Not sure on the roller or flat tappet. May not make a difference other that affect the VE table which provides fueling. You can crutch the VE table by increasing fuel pressure however that is not the best way to tune as it enrichens crank, choke, pumpshot and WOT. Only closed loop(02 sensor) can adjust for higher fuel pressure.

 

More good stuff! I would prefer to use the 8746 ECU that is already in my car. I'm not too worried about the exhaust side as I am running Edelbrock headers, a high flow cat and I have upgraded to a Magnaflow three inch cat back system. Dumb question time: Is the L05 350 different than an L98? I saw references to both. Are the specs on the 083 heads much different than the 081 TPI castings I am running now? I am not aware of a stock configuration of a 350 CID engine with a T5 tranny, so I assume that I will need to modify a chip. Can I modify my stock chip or do I have to go to one of the ones discussed earlier? Thanks for all of the good input!

 

Throwing out a quick thank-you to Thom and everybody else in the matter.
Everything is starting to come together. Taxes will be in soon and I have a game plan for this swap(to try and make it as painless as possible) The L98 is gone at this point. Been looking around on Craigslist for candidates.


As far as the auto/manual chips go, whats the difference?
Ejamacate me please...