Setting Expectations for TBI

[AwesomeJ10]

...And GM TBIs, particularly the 7747, aren't *that* complicated.

Yup. I'm wiring up this vortec 8.1 and man, that thing has a TON of wires. Way more than a 'simple' 7747 (or even 7247) ECM.

Right about now, I'm thinking that wiring up all those junkyard TBI setups REALLY helped gain enough confidence/experience for LS1 swaps.

[Lumpskie]

PS: I see you're local. You're welcome to come by and drive mine and see what ya think.

^That would be awesome. I'm in the Roxborough area, west of Highlands Ranch. I'll PM you my number and we can set something up!

[Bill usn-1]

If you want to learn about carb vs TBI I'll be at the RMIHR-rocky Mountain IH roundup in Salida at the fair grounds the weekend of the 4th. I give a free EFI seminar on Sat. There's also trail rides. Normally some flat landers try to take their carbs up the 14r's and end up blowing black smoke on the side of the trail. I actually arrive the 28th of Jun for a week of wheeling around Ouray.

I'll also be back in Colorado springs around the 13th of Aug for the Hudson Nationals and will provide a seminar there as well.

[will e]

carb:



Of course I just jinxed myself for this year.

[243]

I drove a 79 Waggie with a 4bbl 401 for a few years and logged a consistent 10 mpg with 20/80 city highway driving.

My 78 Cherokee with a TBI 360 gets 11-11.5 with 50/50 city highway driving.

The 360 has not failed to start once and runs smoother, idles better and in my opinion has no faults when compared to a carburetor.


Not trying to be a smartass, but those who rip FI off ~1987+ cars and trucks are insignificant in number and there is a reason for that.

The folks clutching carburetors to their chest seem to be old farts who simply won't take the time to understand the most dirt-simple system on the planet, TBI and chunk the carbs in the trash can. Hell, Bill Hamilton lays it out quite well and there are plenty of other sources for help beyond Binder Planet.

[will e]

The folks clutching carburetors to their chest seem to be old farts who simply won't take the time to understand the most dirt-simple system on the planet, TBI and chunk the carbs in the trash can.

That's just rude. I am an old fart. I have a very good understanding of fuel injection.

[AwesomeJ10]

Lol. I think it would be cool to chat with bill in person. He literally wrote the book on TBI conversions.

[csuengr]

I really miss having a carbed vehicle.

[243]

The folks clutching carburetors to their chest seem to be old farts who simply won't take the time to understand the most dirt-simple system on the planet, TBI and chunk the carbs in the trash can.

That's just rude. I am an old fart. I have a very good understanding of fuel injection.

Me too, last Friday the doc' was pushing the next prostate and colonoscopy exams...at least I didn't have to tell him of chest pain due to a carburetor

[Bill usn-1]

carb:



Of course I just jinxed myself for this year.

Is this pic supposed to imply that a carb is just as good as EFI??
Of course a carb can be tuned to run any where you want to drive it.
But then hop in that same truck with the same tune and drive it back down to sea level or even 1000ft less in elevation.
Of just let the weather change and see how much the tune changes.
Most people have no idea how much altitude, pressure changes, temp changes, can affect a tune. Just watch a drag race and see how much they have to change the tune between rounds to compensate for weather changes.
Most just know the engine starts and runs when they hit the key. For some that's enough..till gas prices go back up.
Tune a carb on a dyno one day and take it back the next and the tune will be off.
Run efi on a dyno and it will be in tune every time.
That's the difference!
All factory systems are self correcting just like the big after market companies advertise. But they have a limit to how much they can correct. That's why we tune.
Here's a write up I did on my experience with the new MSD Atomic TBI system.
If interested, take a look.
http://www.binderplanet.com/forums/inde ... it.128848/

[will e]

Of course not Bill. We have all acknowledged that, generally, TBI's will adjust better than carbs for altitude.

[csuengr]

My 2150 ran fine from 3000 to 13000 ft with no adjustments.

...and, EFI in not in tune all the time. Pull the KAM fuse and see what happens.

[Tatsadasayago]

I guess I am in between here. I like my carbs and EFI equally. My carb works so well that I cannot justify the time and expense to convert to TBI even though I want to badly. With the addition of a manual mixture adjustment system the only area where my Holley cannot compete with TBI is on extreme angles.
In due time I too will switch over but till then I won't try to fix something that isn't broken.

[Bill usn-1]

LOL
You guys will go to no lengths to defend a carb.
It amazes me sometimes the things I see posted on the web.

I just feel bad for the guys that don't know any better and are actually looking for helpful information.
But it gives me plenty more talking points to add to my seminars!

[Stuka]

Carbs are simple and can be made to work well at one altitude. But soon as the altitude changes, or the humidity changes, or temperature changes (etc) they go out of tune (no way to argue this, they cannot adjust themselves). I live in an area where I can go up 7000ft in altitude in 40 minutes of driving. And there is no way to make my truck run well at both ends with its carb. Just have not had the chance to look into putting EFI on it, because it needs it. I am sure its similar to doing it on a V8, just have not seen a writeup for 258s (They may exist, have just not seen it).

[AwesomeJ10]

LOL
You guys will go to no lengths to defend a carb.
It amazes me sometimes the things I see posted on the web.

I just feel bad for the guys that don't know any better and are actually looking for helpful information.
But it gives me plenty more talking points to add to my seminars!

Yep.

[AwesomeJ10]

Carbs are simple and can be made to work well at one altitude. But soon as the altitude changes, or the humidity changes, or temperature changes (etc) they go out of tune (no way to argue this, they cannot adjust themselves). I live in an area where I can go up 7000ft in altitude in 40 minutes of driving. And there is no way to make my truck run well at both ends with its carb. Just have not had the chance to look into putting EFI on it, because it needs it. I am sure its similar to doing it on a V8, just have not seen a writeup for 258s (They may exist, have just not seen it).

I dunno if there really is that much 'difference' between setting up a TBI for a 6 cylinder as opposed to a 8 cylinder. Mostly just the intake adapter. You could grab a V6 or small V8 BIN file, slap it in and adjust from there.

[will e]

LOL
You guys will go to no lengths to defend a carb.
It amazes me sometimes the things I see posted on the web.

I just feel bad for the guys that don't know any better and are actually looking for helpful information.
But it gives me plenty more talking points to add to my seminars!

Yep.

It seems to me the carb guys have all agreed that TBI has advantages over a carb. Including Altitude adjustment, emissions, gas mileage and mostly avoiding the dreaded vapor lock. I think the information we provided the OP was pretty solid. His rig is running fine now so it may not make sense to convert to TBI.
Depending on how much effort and money someone wants to spend even a 10 percent improvement could take 20,000 miles (and probably more) to pay for the conversion. (I figured 10% improvement and $500 spent for the conversion at todays gas prices $2.75). If you drive your rig daily that may be worth it. If may not, especially if it is running fine now and you don't change altitude a lot.

It's the TBI guys who are insinuating that the carb guys are too lazy or stupid. That we are handing out bad advice to people who don't know any better. It's sad the TBI guys have to resort to an argument that if we don't walk lock step with you that we must be ignorant, dumb or just stubborn.

[AwesomeJ10]

no man, I don't think you have it right.

We (the TBI guys) are advocating that TBI is superior to carbs for most uses. I'm especially advocating that if you want a cleaner running, more reliable, better starting, safer running engine (especially for 'wheeling) than any 20+ year old carb can provide, that people should hop on the TBI bandwagon. Or better yet, skip the whole TBI scene and go straight to Vortec.

I don't think Bill or I are insinuating you carb guys are lazy or stupid. Maybe a little stubborn ,but heck, anyone who loves FSJ's is probably at least a little stubborn!

[Stuka]

I don't think anybody can use fuel savings as a reason to go TBI. Like any mod, most of the time its done for performance or drive-ability. If you mod an engine for power, it could cost you thousands for a 20% boost in power. To many its not worth it, to some it is.

I feel the big draw to EFI is that the engine runs better in all cases. You can technically get big power easily with a carb(s), but it requires constant tuning which really only makes it better for racing, and not daily driving. The 2v TBI actually sucks from a power output standpoint, but we are not trying to make 500hp. We are trying to make our rigs run better through altitude and weather changes. Getting out to re-tune the carb in my J10 half way to my destination due to altitude changes sucks. That issue goes away entirely with EFI.

Carbs are simpler, they always will be. And for some thats more important, there is nothing wrong with this methodology. But unless the person is using an old carb to save money, or they are not technically inclined when it comes to interfacing with the EFI, EFI is the better choice.

I am not sure you can even use money as a reason. As a new carb cost almost as much as converting to TBI (Using mostly used parts admittedly).