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To run a Carb or not?

sweetk30 said:
if your thinking holley sniper you beeter read up . . . :whistle:

there is lots of guys jumping to other brands after all the problems and other stuff with the holley sniper and there after sale service be it forum or phone in .

this one is a good read and lots of data in it to back it up . holley sniper problems

and lots of info on efi in here the injection section
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Brett, not everyone thinks the sniper is junk. I get on other forums and they seem to love it.
Also not everyone has the coin for a pro flow 4.
Let the guy make up his own mind.
 
I think it's mostly down to money. If you can afford an LS swap, that would seem to be the best bet...you get everything modern technology has given us in a platform that that the aftermarket has embraced with tons of add ons. But it's going to cost you. You get reliability, fuel economy, better hp and tq across a wide powerband, easy tuning etc. I couldn't afford that. I've got one GM TBI that I modified a little (I did all the Harris Performance mods when I rebuilt it.) I also have a FItech system on a second truck. Between the two, the FItech is way easier to tune and troubleshoot. The performance is better, also, but not enough to make a decision based on that. But getting it dialed in is so much easier without having to run ALDL logs and burn chips I have to go with the FItech as my favorite. Nothing wrong with the GM system, they work almost the same, but you can tune the FItech and get real time datalogging while you drive. That's the advantage to FItech. I know lots of folks have had trouble with aftermarket tbi's. I never had an issue with mine, so maybe it's hit or miss. In the end, I spent more getting the GM tbi to work right than I did on the FITech kit. If you're rich, LS swap a nice turnkey 502 and you'll never look back!
 
TJ1978 said:
My 350 is stock with an RV cam. Nothing fancy.
All Id have to do is swap the intake for TBI one get a the Howell kit and go?
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If you have a stock 350 for 1978, you can't install a factory TBI intake without modifying the center 4 bolts. They are angled differently. I have never tried to do this swap/modification, so I don't know what to expect.
And the thin aluminum adapters for 4 barrel to TBI can bend. @Bent77 and I can attest to that.
If you get serious, I have a custom made adapter that is also a spacer. I have it for sale in the classified section, along with other parts for TBI. It may interest you.

I agree that the aftermarket systems are easier to tune, but a stockish engine is easy for a good tuner. You would want to know your cam specifications to help verify with the tuner, maybe before you make a decision.

I personally like the idea of timing control integration, which the Proflo has and others are capable of with additional parts. GM TBI has it, as well.
 
6872xtc said:
If you have a stock 350 for 1978, you can't install a factory TBI intake without modifying the center 4 bolts. They are angled differently. I have never tried to do this swap/modification, so I don't know what to expect.
And the thin aluminum adapters for 4 barrel to TBI can bend. @Bent77 and I can attest to that.
If you get serious, I have a custom made adapter that is also a spacer. I have it for sale in the classified section, along with other parts for TBI. It may interest you.

I agree that the aftermarket systems are easier to tune, but a stockish engine is easy for a good tuner. You would want to know your cam specifications to help verify with the tuner, maybe before you make a decision.

I personally like the idea of timing control integration, which the Proflo has and others are capable of with additional parts. GM TBI has it, as well.
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Didn't we decide they make a gen1 SBC intake pattern to TBI plenum?

given the new trans and mods, I can understand why @TJ1978 wants to keep those parts. I might be tempted to do cam and heads on what he has, and add injection of choice.
TBI works ok, but the buy-in is prohibitive as it costs as much as aftermarket to start from scratch. An '87 TH400 truck would be a good donor for the system, no TCC, but you still need VSS. Any LS will need a VSS also
 
Bent77 said:
Didn't we decide they make a gen1 SBC intake pattern to TBI plenum?

given the new trans and mods, I can understand why @TJ1978 wants to keep those parts. I might be tempted to do cam and heads on what he has, and add injection of choice.
TBI works ok, but the buy-in is prohibitive as it costs as much as aftermarket to start from scratch. An '87 TH400 truck would be a good donor for the system, no TCC, but you still need VSS. Any LS will need a VSS also
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I'm running the oddball MEFI4 controller on my LS that does not require any VSS signal. It's not the norm, but the stock ECM, if controlling the engine only and not a 4L60e/4L80E or later trans the ECM, does not have to have a VSS signal. Most tuners can turn that input off if you are running the LS on an older trans without electronic controls. The engine don't need to know how fast the vehicle is going as it's looking at MAF for incoming air amount and MAP for a vacuum signal for an indicator of load along with the throttle angle.
 
ZooMad75 said:
I'm running the oddball MEFI4 controller on my LS that does not require any VSS signal. It's not the norm, but the stock ECM, if controlling the engine only and not a 4L60e/4L80E or later trans the ECM, does not have to have a VSS signal. Most tuners can turn that input off if you are running the LS on an older trans without electronic controls. The engine don't need to know how fast the vehicle is going as it's looking at MAF for incoming air amount and MAP for a vacuum signal for an indicator of load along with the throttle angle.
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That's right, thanks for the refresher Zoo
 
Bent77 said:
Didn't we decide they make a gen1 SBC intake pattern to TBI plenum?

given the new trans and mods, I can understand why @TJ1978 wants to keep those parts. I might be tempted to do cam and heads on what he has, and add injection of choice.
TBI works ok, but the buy-in is prohibitive as it costs as much as aftermarket to start from scratch. An '87 TH400 truck would be a good donor for the system, no TCC, but you still need VSS. Any LS will need a VSS also
Click to expand...

I can't remember if there is a TBI to gen 1 SBC intake.

I do remember that the '72 K5 ran well with no VSS. Even though you said that it lost a little power up top.
I would think that the up front cost of TBI should be lower right now because of the parts being common. I would think that more than 4 of us members have the parts to get a system running.
Keeping the rest of the engine and drivetrain alone would be good. . . for now..
:whistle: :D
 
6872xtc said:
I can't remember if there is a TBI to gen 1 SBC intake.

I do remember that the '72 K5 ran well with no VSS. Even though you said that it lost a little power up top.
I would think that the up front cost of TBI should be lower right now because of the parts being common. I would think that more than 4 of us members have the parts to get a system running.
Keeping the rest of the engine and drivetrain alone would be good. . . for now..
:whistle: :D
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Piecing one together for $200 would be ok. Leaves money for pump and return lines
 
LS swap here with factory GM ecm and harness. By far the best investment I’ve made on my truck. Crazy reliable.

You can find almost everything you need in salvage yard or you-pull-it place. LS stuff is everywhere and can be done very cheap if you can do the work yourself.
The actual conversion cost was less than 1k
 
I think today, best options are either a stock small block with TBI, or LS. This is for non-modified applications.

I'd rather have an injected daily driver and a carbed weekend rig, if I was ever going to have a carb again. Were it easy to swap my riding mower to injection, it would be done already. Both my daily and truck are injection. Drive a modern injected vehicle. It or a carb more enjoyable to drive?

I run TPI. It works great, but is a lot more work than TBI to get setup in one of these trucks, especially if you can find a TBI truck as donor. I can tell you unequivocally for all the work I did swapping TPI in (plus cost), I have not seen an increase in MPG on or off road, but from driving a buddies '95 k2500, it has a lot more low end. Regardless, it runs and drives every time I turn the key (barring failures of components, but that is part of having old junk) in any condition. 15*, 95*, hot restarts, angles, sea level or a mile up. I would probably not consider TPI now unless someone dumped everything I needed in a box on my doorstep for $200.

LS is a proven swap, and been done enough that as far as I can tell, there should be no guesswork on what to get, what works with what, etc. I doubt many would say LS is inferior to any previous injection setup/engine combo, the only argument IMO is the cost of obtaining the right components.
 
I'm never going back to carbs.

I did the FAST EZ EFI on my Stepside when it first came out and it's been completely trouble free. It has a few quirks that I wish I could have known about to help in the fine tuning. But still has been better than a carb. It's never going to be as refined as a factory system but it performs well for what it is. I wouldn't buy one again just because there's better options out there now that allow for finer laptop tuning.

On my plow beater I swapped on a factory TBI system. Flawless cold starts and warmups in the dead of winter. No more messing with chokes, just turn the key and walk away. I'm using an adapter and spacer on the factory cast iron qjet intake. If I used this truck more regularly on the street I would swap intakes to a TBI intake.
If you have a factory engine that's in good shape, I highly recommend a factory TBI swap.

I have been diving into HP Tuners in regard to LS stuff and it's absolutely crazy how much stuff there is to mess with. It's a very steep learning curve but there's tons or resources and information out there now to help facilitate learning the program and building custom tunes.
The LS stuff is just so far superior. Knowing what I know now, it's either factory TBI or if you're after more power, then LS Swap and never look back.
 
Love my FiTech, scrapped my carb and will never look back.

Bent77 said:
I vote L29 short block, aluminum heads, and PF4 injection

That ought split that TH350 and maybe the NP203
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That would probably split a TH400 too if it isn't built to hand that :saweet:
 
Chevy305 said:
I have been diving into HP Tuners in regard to LS stuff and it's absolutely crazy how much stuff there is to mess with. It's a very steep learning curve but there's tons or resources and information out there now to help facilitate learning the program and building custom tunes.
Click to expand...

Look up goat rope garage on YouTube. He puts out awesome videos about the HP tuners platform. They greatly helped me get going and confident in tuning.
 
I would like to see the U.S.A. in my chalet,that's all 48 states,all the highs and lows,so I need FI,but got a new create 5.7 so putting a factory fi would be a bitch,,so which is the best??just a 280hp 5.7 with no room. THANKS
 
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