New guy excited about learning how to tune my 454 TBI van.

**rob240z** · 12-21-2014

Hello,

I've been doing a lot of research lately about tuning gm tbi systems. I just recently found this forum and have been reading and learning a lot on here. I probably won't be posting very much as I still have a ton more reading to do first. I'll try not to ask any newbie type questions that have been asked many times before. I just bought an APU1 and G1 from Moates.net and that should be arriving a little after Christmas. I already have a MTL-X from Innovate Motorsports. I'm really excited about this. Merry Christmas to me!

My main reasons for learning tuning are related to the 2 vehicles I currently own. I have a 1995 GMC van with a 454 and 4l80e. It's a quigley 4x4 conversion. I just had to replaced the head gaskets and while that was being done I changed the cam to the summit k1300. It is a mild cam, but is better than stock. The exhaust has been changed to 2 1/2" true duals after the stock manifolds, with high flow cats and glass packs. My plan is to learn to tune this first. It should only need minor changes as it's not to far from stock as is. After I get more comfortable with tuning I'm going to start building the engine up from there.

My other car is a 1971 Datsun 240z with a Chevy 327. It currently has a Holley 750 double pumper that I've spent a lot of time tuning with a wideband O2, but I don't think it is ever going to run the way I want. I had bought a 1995 Chevy van to use as a parts van for my other van. It has rust but runs great. It has a 350 tbi with a 4l60e. I think I want to take all the FI stuff from it and install it in the 240z 327. I'll probably be looking for another 454 throttle body for it though. I had never considered this as an option until I recently started researching options for my van. My plan was to use megasquirt. But now that I know I have a decent computer in my parts van, I should just use it. I'll only have to learn 1 software setup for both my vehicles. Seems like the way to go.

Thanks,

Rob

**fastacton** · 12-21-2014

Welcome! Nice Z! I have TBI on my 280Z with a 350 and love it compared to a carb!

**dave w** · 12-21-2014

Thanks for posting pics. Nice projects to learn with!

dave w

**rob240z** · 12-22-2014

Thanks for the welcome guys!

Fastacton, I'm so glad I went with a v8 in my z instead of building the original L6. It is such a fun, quick little car. People at car shows either love it or hate it. Not many in between. I bet you have spent a lot of time over at hybridz.org. That was an invaluable website when I built mine. Do you have any pictures of your car? I'm curious to hear about how you set up your car with TBI.

I went with the Holley because I wanted to learn how to tune one effectively. I have plenty of experience with the SU's and webers, but felt like any good gearhead should know how to tune a Holley 4-barrel. I think I have it tuned as good as I possibly could considering the engine setup. The engine has a pretty big cam and tuning the idle and just off idle circuit are the most difficult to make smooth. I'm thinking the TBI can help mellow out the drivability in those conditions. WOT is not where I have any problems. I'm really into computers and have been wanting to do this for a long time. I guess it's the next obvious step in becoming a more modern gearhead.

Rob

**fastacton** · 12-23-2014

Yep, gotta love HybridZ for good info! I'm just finishing up swapping in a fresh engine and finally took it on a test drive yesterday. I still have to do some tuning to compensate for the vortec heads and a cam. Here's a picture of the not quite finished install, I ended up ditching the 454 TB adapter because of hood clearance:

Attachment 8284

**rob240z** · 02-21-2015

Hey fastacton,
I'm not sure why I never saw your reply until now. Cool car and project. I hope everything goes well.

I've been doing a lot of reading on here lately and this stuff is a little less confusing now.

This is what I have done so far:

I have pulled the ecm and memcal from the van to identify what I actually have. Sticker on the case says it's a 16196395. I'm pretty confident that is right.
The blue cover over the memcal says Delco 9483 BMHM. Numbers on the chip are 4217 over 1618 over 8020. I thought the chip would have a group of 4 letters too from what I've seen before. Maybe this is a replacement memcal? There is also a group of 4 letters after 16196395 on the outside sticker that reads BHRJ.

I think this is the $0E mask based on the generically looking what bin should be for a 1995 GMC van with 454 and 4L80, but I can't match the 4 letters BMHM or BHRJ in the bin lookup spreadsheet.

I downloaded Tunerpro RT and played around with it with downloaded bin, xdf, and adx files from this board just to try and get comfortable with the program.

I pulled my stock memcal, installed a g1 adapter and hooked it up the autoprom and then it to the laptop to try and read the stock chip. I think I was successful with that.
Attached stock bin below.

In Tunerpro, when viewing the Mask ID in location 4008 it says the Mask ID is BE ($BE). I can't find a match for that anywhere and is another reason I'm thinking the stock bin I downloaded with the autoprom is not correct. File size is 64k, and when I viewed it in the Hex editor it starts on line 00000000 and ends on line 0000FFF0. I think the code looks like it should. the values are mostly different and there's a bunch of weird symbols on the right side.

I used the files from the 16196395 $0E thread.
http://www.gearhead-efi.com/Fuel-Inj...Information-OE

I also tried using the $31 mask too.

The stock bin doesn't look right to me compared to the one's I downloaded from here. A lot of the values seem really off and random when viewing the stock chip.

I also managed to hook the autoprom to the van and did a small couple minute data log.
Attached catalog below.

I was hoping someone on here could at least let me know if I'm going in the right direction.

My main questions are:

Does my stock bin look right?

If I was to download a bin from this website, what would the correct one be?

Also, I was thinking that just modifying the stock bin would be the right avenue to take, since the van runs fine, but would using a downloaded $31 or $0E be a better starting point. The values in the downloaded files appear to make much more sense at least to my beginners eyes.

Thanks,
Rob