TBI to 96-99 CSFI

[Daveo91]

Test the resistance yourself.

Perhaps test each injector with about 35 PSI of compressed air and check for leaks by "dipping" the injector in water. This test only determines if the injector is stuck open. Possibly trigger (momentarily with 12 volts DC) each injector open / closed with 35 PSI of compressed air and repeat the water dipping test.

Risk vs. Cost . . . for an "all-in" budget test . . . install the injectors as is.

I think injector cleaning is typically $18 per injector, which is a bargain for two TBI injectors. Maybe $18 per injector for eight injectors is a bargain?

Thanks, Dave. I'll definitely do some resistance testing!

"1. Install it in my conversion project as is and hope for the best?
2. Would it be useful to test resistance across each injector? Is there a range I’d be looking for, or just consistency?
3. send it to Mr. Injector for rebuild/cleaning?"

The injector is designed as a "plug and play" replacement. Fuel delivery and electrical characteristics are the same as the original part, at least as far as the pcm is concerned. You could measure resistance across a few terminals of the old injector then across the new one for comparison. You could install the injector and connect the fuel lines then key on/engine off and let the pcm test the injectors. You would need a scantool to view the trouble codes. Or you could simply install the injector. We've had very few problems with that style injector here so if that were going into my vehicle I'd probably clean the exterior and install it as-is.

Thanks for the info and the personal experience. I probably will do as you say: some resistance testing and exterior cleaning.

just so you are aware the 7427 will not fire the injectors sequentially. it only will run batch fire and you will have to wire the injectors accordingly. as far as cleaning injectors, i do it all the time now. recently went to the junk yard to get a set of injectors for a civic and then dropped them off to get cleaned. had to go back and get another set (8 injectors total) just to get a good set of 4 FWIW...

EBL is a cool product, but i don't really consider it an upgrade running it in parallel with the 7427. unless you are running forced induction or some other power adder.

Thanks. Yes, I understand that 7427 (and EBL) will only fire the injectors in batch mode. From what I've read, I'm not too concerned about that. As for EBL, agree that having to run a parallel 7427 is a hassle and lowers the value. The benefits as I see it are ability to flash, hi-way mode, higher resolution tables, not having to modify a 7427 for 8 injectors, increased reliability (i.e. less worrying about 30 year old electronics) etc. Still trying to decide if those things are worth the $450.

[tayto]

a datalog cable, chip burner and emulator can be had for less than EBL. especially if you are not in a hurry and don't mind picking up a used one. the 7427 can run a semi-open loop mode to run a leaner mixture. there is also some info floating around out there about deleteing the EGR and hijacking it's parameters so you can change the advance in this pseudo hiway mode. it was done 10-15 years ago. As far as "30 year old electronics" EBL only replaces ONE board in the original ECM. The mainboard is still "30+ years old". EBL is modded in a similar fashion to run PFI, so that is a moot point. the only difference is dynamicefi does it for an additional fee. as far as resolution, don't get me wrong EBL is amazing especially when you go and look at the original 747, but the 7427 is still superior. like i said before if you are going forced induction or power adders EBL is the way to go.

https://www.thirdgen.org/forums/diy-...ml#post3651186

LEAN CRUISE:
a. The $0D mask does not have the ability for spark advance during lean cruise.
however, there is a work around if you don't run an EGR valve. I'm going to reveal
another one of my secrets here. This actually works very well. If you don't run an
EGR valve, which I don't, you can leave the qualifiers set to enable EGR, disable
error 32, and set the Desired EGR table and the Fuel Reduction % w/EGR on table to
all zero's. By doing this you will have zero % EGR commanded as well as zero fuel
reduction (remember you are doing this with lean cruise) but the EGR Spark
Correction table will still apply. You can then set this table to add spark where
you are removing fuel with lean cruise.
As for what you should do to tune open loop fuel safely. That is simple, remove
your cat. Here's what I did, I took my old tired original cat and gutted it. I
then bought a cheap universal Catco converter from Summit and fabbed up the pipes
to be able to replace it when it is time to pass the sniff test, then I remove it
after testing. Cost me like $60 total. This accomplishes two things. I am running
a gutted cat for 51 weeks out of the year and when I do install a cat for testing,
it is like new and a new cat can be very forgiving when getting sniffed. HTH

b. enable open loop and the AFR vs VAC vs TEMP table can be used for lean cruise

[Daveo91]

a datalog cable, chip burner and emulator can be had for less than EBL. especially if you are not in a hurry and don't mind picking up a used one. the 7427 can run a semi-open loop mode to run a leaner mixture. there is also some info floating around out there about deleteing the EGR and hijacking it's parameters so you can change the advance in this pseudo hiway mode. it was done 10-15 years ago. As far as "30 year old electronics" EBL only replaces ONE board in the original ECM. The mainboard is still "30+ years old". EBL is modded in a similar fashion to run PFI, so that is a moot point. the only difference is dynamicefi does it for an additional fee. as far as resolution, don't get me wrong EBL is amazing especially when you go and look at the original 747, but the 7427 is still superior. like i said before if you are going forced induction or power adders EBL is the way to go.

https://www.thirdgen.org/forums/diy-...ml#post3651186

You might be talking me out EBL. I still think there's some benefit, but not sure if it's enough to justify the cost. If it had trans control I think I could much more easily justify. (of course it would cost more then, too). I have cables and chip burners already, been burning chips for years, so that's not a factor, other than the fact that it would be nice to not have to burn chips all the time. Thanks for the TGO link on hiway cruise. I'll check it out in detail. I've read some of the other posts on the subject, but this one is not looking familiar yet.

[Daveo91]

I believe I've hit a show stopper with the stock Vortec MPFI conversion project. The thermostat/water inlet housing on the manifold has an interference with the serpentine accessory bracket system. I'm not seeing a way around it - interference is too great to be solved with just grinding off some metal. I think I'm going to abandon the project unless another solution presents itself.

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I'm going to stick with TBI for now. Although disappointing, the disassembly I did today is not a waste - I'm putting in new roller lifters. (When I rebuilt my engine, I used the lifters from the core vortec engine where I got all the rest of the valve train parts to do the roller conversion. I always regretted that decision and I've since taken apart another SBC that had one of those fail - it pretty much made the block useless)

I'm going to consider some aftermarket MPFI conversion systems eventually. For now going back in with my TBI system - it's been running really good after my tune so I'm not super disappointed. I'm going to see if I can get cruise control working this time, too.

[tayto]

find brackets from 89-93 B-body or 88-92 F-body. they are still serpentine, but the AC and alternator sit much lower. You need to use the same brackets for a TPI swap. I have a core engine in the garage with thia bracket setup on it if you want me to snap a pic....

[Daveo91]

find brackets from 89-93 B-body or 88-92 F-body. they are still serpentine, but the AC and alternator sit much lower. You need to use the same brackets for a TPI swap. I have a core engine in the garage with thia bracket setup on it if you want me to snap a pic....

Thanks for the info and pics. Interesting info. Something to keep in mind for sure if I happen to see one of those cars at Pick-n-pull. Assuming existing alternator, R4 compressor, P/S pump will all fit? Which water pump do you use or are they the same? Did those cars have smog pumps? My burb doesn't and never has.

I've also thought about finding a wrecked 96-99 truck with 350 and using the entire accessory system from it. But, if I go down that road then I might as well use the entire system (harness, crank sensor, distributor, etc) and go OBD-2, possibly 0411 conversion too. But then looking at the time and effort for that and finding a 6.0 LS truck instead might make more sense..... a dangerous game I'm playing here. Sticking with TBI for now!

[tayto]

yes, those brackets use the same R4 compressor, power steering pump and CS130 alternator. if you find a B-body cop car they come with an adapter bracket to run the bigger CS144. Same reverse flow TBI pump as the C/K trucks. Yes they came with smog pump, can use a readily available delete pulley or just get a shorter belt.

it is easy to get carried away... I would personally just get a SBC intake that has provisions for Multi port. I have converted a truck from vortec to TBI. It was a major undertaking. Swapped whole dash & interior harness plus engine harness. LS swap will just nickle and dime you to death IMO. Brackets can be swapped in a day...