tcrisp

what is better and how hard is to switch to the speed den from maf on a 85 tpi that is a 305 but will soon be a 350 ?

vetteoz

iTrader: (13)

Depends

Not hard with a 86 - 89 ECM
http://www.eecis.udel.edu/~davis/z28/ecm_swap_730/

but you have the one year only 85 ECM that requires more mods
Would be easier to get the complete wiring / ECM from a SD car

tcrisp

so i just need to get a 86 -89 ecm and can i still use my wire hanress or do i need to get ecm and the wire harnees?

tcrisp

So after looking at the info will a be better off building a 350 tpi like a 85 350 tpi vette. because i just want a stock 350 that way i want have to mess with ecm but change out the two chips in I just want that torque 330 ftlb. i think that what they had in a 85 tpi 350.

85 ZXX

iTrader: (1)

I did that with my 85 Z28 with a new L98 engine. I found a 85 Vette 4+3 ECM (manual shift) ECM on a Internet search and I went with 24lb Bosch III injectors, ESC module for a 350, knock sensor for a 350, BBK 52mm throttle body and under drive pulleys. The MAF and wiring are stock setup. It scoots down the road pretty good.

TPI

Given what you are trying to do with the car, converting to a speed density TPI system
seems illogical. Mass air flow TPI's being more forgiving to light-to-moderate modifications seems like the logical choice. Since you are just chasing after the torque numbers, id choose the path of least resistance.. Which would be to ulitilize what you have with the '85 harness and ECM and go from there.

tcrisp

thanks guy that what i will do is buidl it like a 85 350 tpi vette. because i do not want to buy a ecm and all the other stuff. Make it easy as swap has possible.

85 ZXX

iTrader: (1)

Good! The ECM is the same, basically the two chips, ESC, Knock sensor and 21lb-24lb injectors. The Bosch III's are nice. I stocked up on the ECM's for my 85 just in case I have some problems on down the road... If you get a one piece main rear seal 350, don't forget to elongate the four center bolt holes on the intake manifold. The bolt angles are different from the older two piece rear main engines like your original. You can see some pics of mine on my signature links below.

tcrisp

Did you use roller cam or a non roller cam .

85 ZXX

iTrader: (1)

The engine I have is a roller cam L98 one piece rear main. 1987 and up.

tcrisp

So i have a one piece rear main 350 block that am going use. will the 85 ecm be able to use a roller cam and not have any issue or will i need to stick with the non roller cam. if i understand that you have a 85 ecm and you are running a roller cam does it matter. sorry for all the questions just trying to get has much info before i start building the motor

Tuned Performance

iTrader: (92)

you should really upgrade to the 1227165 ecm the 870 is a piece of junk. You will have so much better throttle response.

85 ZXX

iTrader: (1)

It does fine...I have no hesitation, I have 193 heads on it with a stock L98 roller cam. The way I understand is that you just want to have a little more power on the pavement and not having to invest a fortune in upgrades.

85 ZXX

iTrader: (1)

You can go this route if you want a new setup:

http://performanceparts.com/part/Pai...firmmobile=yes

It might not work with a 700 R4 transmission though.

vetteoz

iTrader: (13)

Problem is not the '870 ECM but the almost impossible to find , $150+ when you can used ,burn off module unique to a 85 that was replaced with a couple of $12 relays on the '165 MAF cars

Intake bolt angle relates to head style (centerbolt or not ) ; not the block style

85 ZXX

iTrader: (1)

I did mention that I had 193 heads and a 87-up L98 engine

85 ZXX

iTrader: (1)

I seriously doubt that he will use his 85 305 heads on a newer 350 block that he is building...LOL!!!

tcrisp

I have a 2 set of heads to choose from 193 and 810 think that is the casting number .I just need to know if i go with the 870 ecm and use a non roller cam and build it just like a85 vette tpi using the 1 peice rear seal and change out the chips i will be fine . also the guy at tpiparts said i would be fine doing that and changing out injector , esc ,knock sensor i sure be fine.

85 ZXX

iTrader: (1)

Absolutely, I like my 193's... I may invest in a 100-150HP shot NOS setup for my TPI just for a little giddy up every now and then.

Tuned Performance

iTrader: (92)

the esc will have letters or a part number on it and will work on several engines with the correct knock sensor. 16126761 (ANRZ) is discontinued. Replaced with HKR for the 4.3l & 5.7L engines, and HKM for the 5.0l engines.
16022621 (BLH), is for 2.8l, 5.0l, and 5.7l engines.

You will need to buy a new knock sensor though.

85 ZXX

iTrader: (1)

The 870 is slow for real time data logging on a laptop but it works.