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bigbluefj
03-26-2008, 09:36 PM
So i'am trying to decide wether to keep using the fuel injection system i have or go back to a Carb system what does everyone here like...???



kevin

Uncle Ben
03-26-2008, 10:15 PM
So i'am trying to decide wether to keep using the fuel injection system i have or go back to a Carb system what does everyone here like...???



kevin

This is a joke...right?:rolleyes: If your serious and you actually think a carb would be mo betta then you do not have a good FI system!

wesintl
03-26-2008, 10:17 PM
seriously... whenever I'm wheeling the diesel at altitude or stop it on a good angle I thank the mechanical injection gods ;)

Romer
03-26-2008, 10:24 PM
Fuel Injection

I have seen treeroot take on some obstacles and the only thing that stopped him was the carb.

Maybe you need a better fuel injection system

rover67
03-26-2008, 10:57 PM
umm... fuel injection.

but that's just me.

it stays happier longer. usually.

DaveInDenver
03-27-2008, 06:42 AM
Love to have the simplicity of a carb. If I could rip off all the emissions stuff and go to a carb, I would in a heartbeat.

Uncle Ben
03-27-2008, 07:25 AM
Love to have the simplicity of a carb. If I could rip off all the emissions stuff and go to a carb, I would in a heartbeat.

Hmmmm.....Thats like putting film type cameras in your Seekr project! :rolleyes:

Red_Chili
03-27-2008, 07:32 AM
I know carbs and am pretty good at dialing them in. Had good luck with a Weber on an Isuzu, rejetted a work car that would die on left hand turns (NOT good) and had the thing running better than any other one in the fleet (this enterprise included precision drilling of the stock jets, not for the faint-hearted). Years of twiddling with motorcycles taught me a lot about carbs. They hold little mystery for me and perform well.

Go fuel injection. :thumb:

DaveInDenver
03-27-2008, 08:01 AM
Hmmmm.....Thats like putting film type cameras in your Seekr project! :rolleyes:
What's funny is that the reason we exist is that for years they used magnetic tape, reel-to-reel even. But don't laugh, some things are not as advanced as you might imagine. Think Apple Macintosh Plus (http://www.old-computers.com/museum/computer.asp?c=282) and you might (or might not) be on the right track for some parts of your hundreds of million dollar satellites.

BTW, it's been almost 8 years since I last worked on a carb, so the bad memories of flooding, vapor lock and elevation tuning are fading. Roll dream sequence. Actually, I like the EFI in my truck and once I get nailed what's causing the wonky idle and mid-throttle stumble, I'll be much happier. I'm pretty sure it's the fuel pressure regulator, but don't have the SST fuel pressure tester to check. If only Toyota had put a friggin' Schrader valve on the fuel rail, it would be simple. But no, gotta use the cold start injector port. :-/

Anyway, it's been said before and it worth repeating... IFS, er, EFI is for losers.

Red_Chili
03-27-2008, 08:09 AM
The launch vehicles I worked on had to have 1960s electronics custom manufactured because that was the design that was qual tested. Mac Plus? I only wish. What is the cost of sending a 3lb. NOT gate up in the air?!?

Drill your fuel rail and install a Schrader valve or pressure sensor.

Linkie to Roger Brown's site (http://www.4crawler.com/4x4/CheapTricks/Gauges/index.shtml)

DaveInDenver
03-27-2008, 08:20 AM
The launch vehicles I worked on had to have 1960s electronics custom manufactured because that was the design that was qual tested. Mac Plus? I only wish. What is the cost of sending a 3lb. NOT gate up in the air?!?
Well, there's using tested technology and there's being silly. Hey, wasn't it you who was calling me silly for sticking with the 22R-E because I knew as much about it as any other engine? ;-)

Anyway, I'm not sure trying to ask Ada and a MIL-STD-1750 MPU to do the thing we are is the best solution, but it's what you got. The problem is not so much finding suitable processors, it's finding rad hard ones. All the people who have good ones go and make them proprietary and either ya can't get 'em or they are very expensive. So we use what we can.

Drill your fuel rail and install a Schrader valve or pressure sensor.
Yeah, I saw that and the light bulb didn't go on until AFTER I'd reassembled and installed the engine. Duh. Lots of things I wish I could go back and redo...

subzali
03-27-2008, 08:45 AM
Kevin, sounds like you need a new fuel injection system. Chevy TBI is pretty cheap.

J Kimmel
03-27-2008, 09:28 AM
not even a question...stay EFI. My carb runs pretty good, but I tuned it and had to learn to drive it three footed. The only time I have trouble is on big climbs, and I've found several instances where I could've made it had the truck kept running.

Oh and I am pretty sure it vaporlocked on Holy Cross last year...we were making good time heading up, perfect day, and had to stop and wait about 20 minutes for some Rovers...I hop back in to go and she just cranks and cranks and cranks some more. After fiddling with it for 15 20 minutes it started up.

I'd have none of these problems with EFI, my last truck never had a question if it would run or not. I've got all the parts in the garage for it now-anyone up for a head swapping party? :D

rover67
03-27-2008, 07:17 PM
headswapping party....yes YES!

Evrgrnmtnman
03-27-2008, 07:30 PM
No Brainer! Fuel Injection......Do they still make carbs? Oh yes, Summit Racing......

Rzeppa
03-27-2008, 10:41 PM
Well, there's using tested technology and there's being silly.
Anyway, I'm not sure trying to ask Ada and a MIL-STD-1750 MPU to do the thing we are is the best solution, but it's what you got. The problem is not so much finding suitable processors, it's finding rad hard ones. All the people who have good ones go and make them proprietary and either ya can't get 'em or they are very expensive. So we use what we can.

Heh. How about a Rockwell 1802 (the predecessor to the 1602 used in the original Apple IIs)? We used to used them in our thick film hybrid (more 1960s space technology) because they were reliable at 150C due to being rad-hard and 100 micron features helped. With a 1MHz clock these eight bit bad boys were smokin!

As for the FI vs carb debate, my take on it is given the choice (with financial and practical concerns taken into consideration), my carbed cruisers do fine, but I look forward to that TBI and megasquirt conversion one of these days. My vote is for FI.

J Kimmel
03-27-2008, 11:03 PM
As for the FI vs carb debate, my take on it is given the choice (with financial and practical concerns taken into consideration), my carbed cruisers do fine, but I look forward to that TBI and megasquirt conversion one of these days. My vote is for FI.


there is an interesting point...exactly the reason I have this far stayed carbed. I was getting ready for a trip, figured out the head wasn't compatible, and frankly spending the money for a new head at the time wasn't really an option so carbed it was.

corsair23
03-28-2008, 02:01 AM
Interesting discussion...What do you all think the typical cost would be to FI and 2F in a 40?

My reason? I have a Weber carb on the 40 now which seems to be a pretty unpopular choice for many I've spoken with. Going back to stock doesn't seem feasible at this point given what I know has to be done to swap out to a Weber. I know some of my issues with the 40 are carb related (those on the 40s only run know what I mean) which are beyond my skill level and I haven't found anyone in town that wants to work on a Weber :( - I know I probably need to rejet the carb for the higher elevation (40 came from CA) at a minimum.

So, are we talking $1000s or $100s or ?? to FI a 40? Maybe FI would be the answer to my problem on that score...

Red_Chili
03-28-2008, 08:22 AM
I like Webers in general. They improve much with proper jetting. They are as precise as motorcycle carbs, which is pretty darn good.

Whatsit doing?

DaveInDenver
03-28-2008, 09:08 AM
I know people seem to dislike the Weber 38/38 on the F engines, but in the mini truck world the Weber 32/36 on a 22R with a mild cam is supposed to be the bee's knees. But at the same time a tuned stock carb on the R motors isn't a terrible carb either. Dean's 20R with it's rebuilt stock runs very nice,but he's flooded a few times when we've been out.

On a 2F I wouldn't necessarily go out of my way to do a FI swap, but then again I never had much issue with that Holley 2300 on Root's truck with the limited stuff I did with the 40. Once he started using the Technicolor Cruiser to its full potential, the Holley limitations became obvious. In my mind it's a matter of application. A well tuned carb works just fine and is simple, but if you find you need FI, then you need it.

But keep in mind that there are critical sensors in FI which if they go bad, there ain't much you can to do jerry rig it to run. So your repair plan needs to include more spare parts rather than just bailing wire, JB Weld and NASCAR tape. Ideally for a long trip you'll have backups for the critical stuff and that's not chump change.

corsair23
03-28-2008, 01:05 PM
I like Webers in general. They improve much with proper jetting. They are as precise as motorcycle carbs, which is pretty darn good.

Whatsit doing?

Around town it seems fine, albeit extremely thirsty :confused: - I haven't tracked mpg real close but it under 10. On the 40s only run I fueled up before leaving and made it back on fumes pretty much.

On the run it seemed fine until we approached the top of Kingston peak. It died going up the semi steep approach at the top and didn't want to keep running. On the way down the other side it would die if I pushed in the clutch and then just above Alice to all the way past Idaho Springs it was back firing. Once over Floyd Hill it returned to its "normal" self.

Around town what I notice most is an occassional desire to "bog down" if I floor the gas in 3rd or 4th gear and an occasional desire to not want to run (i.e. lose power) when climbing an incline and trying to add throttle.

I chatted with Jim C about a rebuild but he won't touch Webers for 40s :( - Webers for other vehicles he will rebuild no problem but not for the 40s. My next step was to buy a Weber manual, new higher elevation jets and whatever else would come in a rebuild kit, and muck my way through a rebuild. My goal is to have the 40 ready for CM09 :rolleyes:

Red_Chili
03-28-2008, 02:17 PM
Around town it seems fine, albeit extremely thirsty :confused: - I haven't tracked mpg real close but it under 10. On the 40s only run I fueled up before leaving and made it back on fumes pretty much.

On the run it seemed fine until we approached the top of Kingston peak. It died going up the semi steep approach at the top and didn't want to keep running. On the way down the other side it would die if I pushed in the clutch and then just above Alice to all the way past Idaho Springs it was back firing. Once over Floyd Hill it returned to its "normal" self.

Around town what I notice most is an occassional desire to "bog down" if I floor the gas in 3rd or 4th gear and an occasional desire to not want to run (i.e. lose power) when climbing an incline and trying to add throttle.

I chatted with Jim C about a rebuild but he won't touch Webers for 40s :( - Webers for other vehicles he will rebuild no problem but not for the 40s. My next step was to buy a Weber manual, new higher elevation jets and whatever else would come in a rebuild kit, and muck my way through a rebuild. My goal is to have the 40 ready for CM09 :rolleyes:
Yeah, too rich.
Start with a few steps leaner for the pilot and main. I do not know, but would guess, that to be maybe 3 or 4 steps leaner, but a decent carb guy or Weber vendor can tell you. Bracket it, so you end up with knowing where it is so lean it bogs (and maybe pings a bit), and go a step or two richer from there. Start with the mains, then do the pilots.
The real way to set it up is with a sniffer of course, but you can get closer than where you are now by feel.
Not sure how your Weber meters cruising speed but that will likely need to be tweaked leaner too.
Get a manual and next club meeting over :beer: we can plan the devastation.

Or at least I can dispense advice that will get you deep in pucky.

corsair23
03-28-2008, 02:24 PM
Get a manual and next club meeting over :beer: we can plan the devastation.

:cool:

Will do Bill and thanks :thumb: - How about after CM08 though...I've got a lot to do on the LX to be ready for CM08 still :hill:

rover67
03-28-2008, 03:54 PM
i can help on the weber too, i've tuned lots of them, and had one on my 2f. i really like them. I had a handfull of jets for my truck, i'll try to see if I can find them. otherwise, take the top off of yours and see what jets yo uhave then order a few different sizes from wherever.

Rzeppa
03-28-2008, 05:36 PM
I can't say enough good things about Jim's Aisan rebuilds. I average 16MPG in my 71 and have gotten over 21 on occasion.

I've seen Webers serve adequately in Land Cruisers, and no doubt, a new something usually works better than an old, worn out something. But I don't like the way you have to jury rig the throttle linkage, I don't like the little air cleaner and I hate the electric choke. And I don't like their (lack of) fuel economy compared to a properly set up stock Aisan. Don't forget that the distributor and valves work hand-in-hand with the carb. Without proper distributor advance under various conditions, good performance and economy can never be achieved. Valve timing and compression affects the relationship between spark timing and carb setup as well. A properly running engine has a whole cast of characters that all must work in harmony to get best performance and fuel economy.