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TA670, Holley Commander 950, or stock tbi...UPDATE tbi questions inside

Which one?

  • Holley Commander 950

    Votes: 1 14.3%

  • Complete stock tbi set up

    Votes: 4 57.1%

  • Holley Truck Avenger 670

    Votes: 1 14.3%

  • Run it nekid like a diesel!

    Votes: 1 14.3%
  • Total voters
    7
  • Poll closed .
GsxrMike

GsxrMike

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I have the chance to buy a complete set up for either stock tbi w/ manifold, ecm, sensors, wiring harness, fuse box and everything, or a Holley commander 950 (wideband) with everything. They are both around $400-$450. I have done research but they are always compared to a carb and never to each other. For the $400 I could always get a truck avenger and save the headache but loose a little on the inclines. I dunno, what say you?
 
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Oh yeah I think I might also have a qjet in my basement but it will have to be gone through probably. I don't know if it will fit in place of my 1406 eddy. Is the qjet spread bore? I think the 1406 is square, maybe my manifold does both, I can't remember.
 
I wanted to the whole fuel injection idea but i decided on the truck avenger 670, it was cheaper in my situation. It works great but took a bit to get it set up on my 358, in the long run the carb works good and with the elec choke its real good when cold out. If it was me id just buy a carb, but if you do have a motor in more stock form with a few mods the injection might be good. I didnt want the hassle and bolted the t/a on....some others here might have more for you on the injection idea, Im dont like the used motor parts idea myself.
 
Here's what you need to consider:

Stock TBI will need mods, upgrades, custom chip to run on a built engine, ie; the one in your sig.

The Holley cmdr 950 is programmable right from the start but not "plug and play".

The carb you can adjust to your liking fairly cheap and easy right out of the box.

My favorite would be the stock TBI for ease of use, parts availability, swapability, general common diag/repair knowledge thanx to sites like CK5. But you are limited to it's abilities if you have even a mildly built engine. Sure, you can mod it and upgrade it to suit your engines needs but that will cost money on top of the original buy in. Would I pick this in your situation? Prob not. If you owned it from the start and just had to pay to mod it, then yes.

The carb is just about "bolt on and go" as it gets. I would recommend an Edelbrock over a Holley any day of the week, but that's my opinion. I would even go one further and recommend a q-jet over both. This one got my vote.

The Holley cmdr 950 is not a plug and play unit either. It will take time and programming to get it tuned right. Plus a laptop if you don't already have one. A guy in my local club had this on his CJ V8 whatever. I never saw his truck for like 2 years. Every time he would take it out for a run there would be some problem and it always led back to the injection. He took it off and replaced it with a carb and hasn't been happier, plus has been wheeling since last summer.
 
Here's the problem I am having, the carb I have is set up great but during a test run the other night I decided to climb a 6'-7' creek bank that was pretty much straight up and down for the top 18" or so. It was very wet because we have had a lot of rain and I never thought I would make it but we decided to try anyway. I could put the front tire almost to the top with no problem but if I tried to get up it with a little momentum and a lot of skinny pedal it would fall on its face. Seemed to me it was running out of fuel but after a couple of days of reading and thinking, I think it may be fuel pouring out of the vents and flooding my motor (although it doesn't even hint at this on another creek bank that is not quite as steep so maybe it is running out of fuel at the extream angel). I would let it sit for a minute and it would start back up with a little finnese (I can't speel). I bought the spring loaded needle and seat deal a few years ago but didn't install it because I was scared of my carb. I feel more comfortable now so I may try to dig the kit out. I am thinking I could install that kit, lower the floats a bit, lower the fuel pressure a bit, and if possible, install a vent tube on my 1406 like the TA has. (anybody ever tried this?) The carb runs fine 98% of the time (even on fairly steep banks/hills etc like most things I have read say it won't) but if I can get up this creek bank I will have accomplished something that I would have never though possible in something that I built and that would just make my day.
 
Oh btw I got my rear tires all the way to the top but couldn't get enough wheel speed to get over the lip because my motor was losing any sense of being a V8.
 
Mike, I've had great results with my TA670 and previously modded 3310-1 Holley carburetors. They even ran with the truck flopped on it's side. That said, I'm not climbing sheer cliff faces either.

EFI is great provided you're prepared to program. BTW, the commander 950 is way too big for a 350 though.
 
BTW, the commander 950 is way too big for a 350 though.
Click to expand...
Not true. The 950 is just an air valve. It's the amount of fuel the injectors put out that makes the difference. This is where injector timing and pressure all comes in to play, hence programming.
 
Hands down, stock TBI. If your engine isn't much more then what is in your sig you will be fine. You can get a new chip if you want to get a little better tune and take some of the things out like the knock sensor, egr, oil pressure switch. Your sig is basically what I have now with a stock TBI. I am calling Howell in the morning to get a new chip to get rid of the vss, egr, and oil pressure switch. I might even ditch the knock sensor. I am sure you looked at everything on http://www.tbichips.com/ to see what you can do. On a side note the Bronco in my sig runs a Howell TBI set up on a 350 hp 302.
 
Well the motor has a mild hydrolic roller cam, and center bolt heads, along with the stuff in my sig but I don't think that will make a huge differance. I may try to get the tbi stuff and then try to eliminate the problems with my carb. If I get the carb to work I am sure I can sell the efi stuff for what I would have in it. I will check out tbichips and do some research. Thanks guys!
 
496truck said:
Not true. The 950 is just an air valve. It's the amount of fuel the injectors put out that makes the difference. This is where injector timing and pressure all comes in to play, hence programming.
Click to expand...

True regarding the fuel curve but does velocity still make a difference for MPFI? Generally the dry flow rating of the throttle body in an EFI should still match the CFM requirement of the engine.
 
Well I got the tbi stuff off ebay for $400 shipped. I did a little reading over at tbichips and I think this will be the best route! I would like to make it as simple as possible so I have alot of research ahead of me! Thanks guys!
 
The 1 thing I am pretty sure of is I will continue to run TBI engines. Yes the LS stuff is nice but I guess I am just to old school. I figure a TBI 350 making 350 hp will be plenty for what I do and still have enough to do some rock racing.
 
I see you went for the stock TBI, which IMO is a great choice. :waytogo:

Regarding the 1406 Edelbrock. It's a POS, and will always be a POS no matter what you do to it. You may slightly lessen it's ability to be a POS...but that's about it. IME it will always let you down and crap out when you need it the most off road. "It runs great on flat ground"...ok, but it doesn't even NEED to be running good on flat ground. Nose up, trying to climb something stupid is when I NEED my junk to run good. Nothing is worse than having to try to re-start a flooded engine when you're halfway up something steep and tricky.

Rene
 
rcamacho said:
True regarding the fuel curve but does velocity still make a difference for MPFI? Generally the dry flow rating of the throttle body in an EFI should still match the CFM requirement of the engine.
Click to expand...
You are correct, you shouldn't run a 1500 cfm t-body on your typical small block. But 950 would work fine. In fact, isn't a stock q-jet rated at 850 cfm? On an MPFI the fuel is atomized at the end of the fuel injector nozzle which is pointed into the head right at the valve. Velocity in MPFI is not a factor concerning atomization. Velocity is created in the size of the intake runners. How much air you can fit in there is determined by the air valve (throttle opening).

I could be wrong, we're talking 1996 when I was going to school for all this. It's been a long time...
 
WOW there is a lot of information on tbi. I have been reading and reading and reading and I think I am dumb now that when I started. Quick questions:

How much fuel will I need and at what pressure?

What is the best way to figure out the duration and LSA of my current cam?

What is IAC valve mean and do?

Is TPS a throttle position sensor? If so does that mean drive by wire? I though 87 would still be cable operated?

I have been doing a lot of research on thirdgen and tbichips, you guys have anymore suggestions?

Thanks!
 
Your best bet for fuel supply, get a sending unit from an injected truck. Someone here will tell you what pump to run if not a stock one. Or you could just plumb in and run an in-line pump under the truck, someone here may have advice on what works best.

IAC = Idle Air Control this is a computer controlled valve the regulates idle speed. Unlike the old carb idle adjustment screw which opens/closes the throttle blades to adjust idle speed, the IAC opens/closes an air passage inside the TBI.

TPS = Throttle Position Sensor. The ECM needs this to compare against readings from the MAP sensor. In short, this is how it determines engine load and how much fuel to deliver. The throttle is cable operated. The TPS is on the pass side of the TBI and reads the position of the throttle shaft.
 
Cool thanks for the info! I am currently running a mr gasket pump because my high dollar holley was to loud. I am running a fuel cell so I have to run an inline pump. Anybody else have any advise?
 
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