: Daily Topic-- Carb vs. Fuel Injection


Scout Dude
10-29-2001, 06:19 AM
Which do you prefer? Why? What type of terrain do you wheel on most of the time? Include any other information that you feel is relevant.

That Mick
10-29-2001, 08:19 AM
Propane

Scout Dude
10-29-2001, 08:35 AM
Originally posted by lilgreenscout:
<STRONG>Propane</STRONG>


Okay, so we left this one out of the choices...however, you never answered why. What happens when your vacuum operated lock-out fails? What about when you run out of Propane? What about if you experianced a loss of coolant and your propane converter iced over?....Lots of possibilities with propane...

jdjanda
10-29-2001, 09:07 AM
No doubt about, fuel injection is the way to go. My current setup is a 2 barrel on the 345. Not bad performance, does lack some punch, but that could be due to a 2 barrel vs. a 4 barrel. Right now, I only have problems with loading on very step ascents, and off-camber situations. A few revs on the motor usually clears the problem. I had planned to use a Projection kit, but after reading this post Fuel Injection (http://www.pirate4x4.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic&f=10&t=014799) It sounds like Pro-brokection to me. So change in plan, sounds like a Howell kit me. Howell Fuel Injection (http://www.howell-efi.com) I'll start gathering the parts for the bone yard, then buy a chip from Howell. Anyone have any experience on the kits?

The setup and forget design of fuel injection is what attracts me. Carbs are simple to make work, difficult to make work well. Carbs are not self calibrating, another draw back, who among us wheels at the same altitude we live? If reliability is the question, carry a spare carb, and fuel pump.

Joe

NotQuiteSane
10-29-2001, 09:15 AM
There's no such thing as a carburated diesel.

<IMG SRC="smilies/biggrin.gif" border="0"> <IMG SRC="smilies/thefinger.gif" border="0"> <IMG SRC="smilies/biggrin.gif" border="0">

tsm1mt
10-29-2001, 09:25 AM
Originally posted by jdjanda:
<STRONG>No doubt about, fuel injection is the way to go. My current setup is a 2 barrel on the 345. Not bad performance, does lack some punch, but that could be due to a 2 barrel vs. a 4 barrel. I had planned to use a Projection kit, but after reading this post </STRONG>

I like my reliable 350cfm 2bbl, but I agree - it lacks some punch. I had a 600cfm square bore 4bbl on my 345 for a while.. yeee-haww.. too bad the moment I got out of the loud pedal it would dump fuel all over the intake from the worn out throttle shaft..

Back to the 2bbl. <IMG SRC="smilies/wink.gif" border="0"> I have a 500cfm to try out soon.. and a couple new 4bbls to experiment with whenever I feel the urge to yank the intake again.

I bought a used ProJection 2bbl when I was building the engine, but my best guess is the computer is FUBAR, so it, too, got tossed into the pile and back on with the 2bbl. <IMG SRC="smilies/wink.gif" border="0">

'course, now I'm thinking the 2bbl ProJection would be insufficient anyhow - it's only rated for 275 horse.

And I don't wheel at my "home" altitude - I'm somewhere above 4,000' at home.. and we climb mountains all the time.. and then I'll go to Colorado and try 14,000'.. or Seattle at sea-level.. all within a week.

BTW, I thought my 196 1bbl was gutless at 4,000'.. but it was a POWERHOUSE compared to the same 196 at 12,000'+..

It wasn't too bad in Seattle.. <IMG SRC="smilies/wink.gif" border="0">

-Tom

Scout Dude
10-29-2001, 10:29 AM
Okay, he's my take on it...I would love to have the performance of fuel injection...I don't think that anyone argues that it doesn't perform better than a carb...However, I don't want to rely on a computer to get there and back. I was originally thinking about go Pro-(joke)tion but I have since decided that I am going to use a q-jet. I have wheeled with a guy who has his set up perfectly and it doesn't even sputter when he is off camber--He runs a FJ40 with full width axles--He goes extremely off camber alot. After seeing how his performs, I think that I will stay Carb.

And Lilgreenscout...I was just kidding about the post earlier...I used to be a Forklift mechanic and I am still tossing around the idea of a dual fuel set-up in the future.

Imagine high HP carb set-up...switch to propane on the trail. <IMG SRC="smilies/smile.gif" border="0">

nwmud
10-29-2001, 11:50 AM
Early this year I watch someone in a newer truck roll it over in a ditch. <IMG SRC="smilies/jeep1.gif" border="0"> I wa the first one there and stopped to help. He was confussed and wanted to leave, but his truck was still running - Good. Finally got the truck turned off and medics took him away. I remember thinking "Man, this truck is running sweet - got to get me some EFI!" <IMG SRC="smilies/biggrin.gif" border="0"> <IMG SRC="smilies/biggrin.gif" border="0"> <IMG SRC="smilies/biggrin.gif" border="0">
I don't like the idea of the computer crapping out on you, but going upside down is pretty cool.
Ritch <IMG SRC="smilies/nuke.gif" border="0">

tsm1mt
10-29-2001, 12:13 PM
Originally posted by nwmud:
<STRONG>Early this year I watch someone in a newer truck roll it over in a ditch. <IMG SRC="smilies/jeep1.gif" border="0"> I wa the first one there and stopped to help. He was confussed and wanted to leave, but his truck was still running - Good. Finally got the truck turned off and medics took him away. I remember thinking "Man, this truck is running sweet - got to get me some EFI!" <IMG SRC="smilies/biggrin.gif" border="0"> <IMG SRC="smilies/biggrin.gif" border="0"> <IMG SRC="smilies/biggrin.gif" border="0">
I don't like the idea of the computer crapping out on you, but going upside down is pretty cool.
Ritch <IMG SRC="smilies/nuke.gif" border="0"></STRONG>

Yeah - but does his oil-pump run upside down, too? Ouch.

TERRA-IZER
10-29-2001, 01:01 PM
I love my carb (750 q-jet) it takes alot to flood it out and when it does it starts right up, unlike the Eldbrock (junk off-road even with the off-road kit), i run a electric Holly pump and the q-jet on a spread bore intake, and it just lugs over and up everything with out hardly a problem. I would like fuel injection but i'am cheap, everytime a newer GM truck comes into the pick and pull some one allways gets to the throttle body and computer before i can. I'am in colorado and wheel above 6,000 feet

Cliffy [JD]
10-29-2001, 04:21 PM
I'm a carb guy but I'd take EFI for my caddy engine given the chance (I wouldn't waste the money on my chevy engine since I know I'm gonna be swapping in the future anyway)

When I first put my 350 in my blazer I had rebuilt the QJ-carb, not my first QJ rebuild but apparently my best, here's why.

I lived in greeley colorado (not sure what the altitude is there but it's around 3,500 I think.) And it ran really well in town. And I'd go to the mountains to wheel all the time (12,000 ft +). off-camber, nose-down, nose-up, both.... whatever and NEVER had any trouble. I loved it.

On a side note: My buddy had a jeep with 350 & a QJ also (that I rebuilt) and his had problems even in town. (he was kinda pissed about this) The only thing I did different was that he wanted me to set his Float higher for him so he would have a larger fuel "RESERVE" for punching it. I'm not into that so I lowered mine.

Guess what I'm doing next time I rebuild one. And I have to soon since my current one is leaking out the side.

mkeown
10-29-2001, 08:03 PM
I have the 2bbl Projection on my 345 and I think it does pretty well. Its way better than the 4bbl Thermoquad as far as power and driveability. I havent had a chance to wheel with the Projection yet because of auto trans troubles, but now thats solved. Yeah if the computer takes a dive, your stuck, but I think it was a very worthwhile mod.