Looking for an air cleaner solution for 2F TBI conversion.

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fabiodaddy

10 Year
Joined
Jul 6, 2012
Threads
18
Messages
85
Location
was UTAH, now Eastern Oregon
I am just finishing up a 4.3 TBI conversion on my 1976 FJ40. I purchased the kit from AFI and they do not supply an air filter assembly. I want to keep the stock air cleaner if possible which means I will need to come up with an adapter to fit the GM 5 1/8 inch opening up to our @ 3 1/4 air cleaner. Tall enough to clear the injectors, but low enough to not hit the hood.

Anyone have a good solution for this? Here are some of the options that I have come up with.

1. I found old posts mentioning 4Plus made some adapters at one time, but I don't see them on his website. This would be good as it is for the stock air cleaner. Not sure if those are still available.

2. Downey had at one time an air cleaner assembly, not sure if those are still available. I would prefer to keep the stock air cleaner, but this might work. Con: not stock and would probably not be great for off-road use.

3. Similar to the Downey one I have found a cheap after market from O'Reillys that might work. It may have clearance issues with the throttle cable bracket. Con: not stock and would probably not be great for off-road use.

4. Another solution was to get a K&N cold air intake for the 4.3 TBI and use that. Kind of spendy but would probably work. Con: not stock and would probably not be great for off-road use.

5. Build an adapter to use the existing air cleaner. Problem with that is I need something to make it out of. I have not found anything that is the right size, and yes I have even looked desperately at coffee cans!!

Any others?
 
fabiodaddy said:
I am just finishing up a 4.3 TBI conversion on my 1976 FJ40. I purchased the kit from AFI and they do not supply an air filter assembly. I want to keep the stock air cleaner if possible which means I will need to come up with an adapter to fit the GM 5 1/8 inch opening up to our @ 3 1/4 air cleaner. Tall enough to clear the injectors, but low enough to not hit the hood.

Anyone have a good solution for this? Here are some of the options that I have come up with.

1. I found old posts mentioning 4Plus made some adapters at one time, but I don't see them on his website. This would be good as it is for the stock air cleaner. Not sure if those are still available.

2. Downey had at one time an air cleaner assembly, not sure if those are still available. I would prefer to keep the stock air cleaner, but this might work. Con: not stock and would probably not be great for off-road use.

3. Similar to the Downey one I have found a cheap after market from O'Reillys that might work. It may have clearance issues with the throttle cable bracket. Con: not stock and would probably not be great for off-road use.

4. Another solution was to get a K&N cold air intake for the 4.3 TBI and use that. Kind of spendy but would probably work. Con: not stock and would probably not be great for off-road use.

5. Build an adapter to use the existing air cleaner. Problem with that is I need something to make it out of. I have not found anything that is the right size, and yes I have even looked desperately at coffee cans!!

Any others?
Click to expand...
A lot of 4plus products' merchandise is not on their website, you have to call them.
 
With all the hopped up diesel pickup's running around, many are running straight exhaust systems which require reducers or enlargers in their systems. Look for a reducer adapter were they sell these systems. Did you Google the size of adapter you are looking for?
 
Some tbi setups use a hat on the tbi and a remote air filter Look Chevy vans the tbi top is common size to most carburators
 
Downey TBI air cleaner still available, see ebay #252403761040
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If you want to run the stock air cleaner, give the 4plus guys a call. I just purchased the adapter from him less than a month ago. No, it's not on their web site but I believe he told me they've got some more of them. Just used it on my 1975 40 with the AFI kit and it worked like a charm.
 
I contacted Dave at 4Plus and he still had a few of his adapters left. I have one of those on order (Thanks Dave!).
Farmboy, its good to hear that the adapter worked out well. I really wanted to run the stock air cleaner setup as I didn't like my other options all that well.
Farmboy, how did your conversion work out? Is the rig running good? Any issues? I am close to firing mine up for the first time. Have a few more wires to connect and I should be ready to test it.
 
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She seems to running great so far! I'm just wrapping up a 3 year nut and bolt restoration. The engine was completely rebuilt when I installed the TBI setup. Really, I didn't expect much when I turned the key for the first time but to my surprise, it fired right up! Since initial engine break in, I've put about 10 miles on it and it seems to run well (all 135 hp of it) with no problems so far! Cold idle and throttle response are great. It passed Oregon emissions very well too, easily exceeding requirements. So far I'm very happy with the conversion. Don't mean to hijack your thread but here's a photo of the near finished product.
 
Fabiodaddy and Farmboy, I am thinking about putting TBI on my '70 FJ40 with the stock F engine. Any pictures of your install, lessons learned, etc would be greatly appreciated. Why did you choose AFI over Howell?

Thanks

Dave
 
David, I did complete the AFI install and so far the rig runs great. I still have a high idle speed (1000 RPMs) that I need to look at, but it starts right up and runs great.

Couple things I need to address:
1. High idle speed. I've contacted AFI and they have a few steps to take to adjust the idle speed. Hopefully that will work. There is also the issue that AFI doesn't use a VSS (vehicle speed sensor). Downey mentioned known issues with systems that don't use a VSS. Hopefully I can sort that out without the need of a VSS.

2. I have already run into an issue where the fuel line clogged up. I'm guessing I must have some debris in the tank that will probably become a bigger issue now that I am running an electric fuel pump at 15psi. I noticed that my fuel tank looks a little different that what I expected for a 1976 FJ40 (fuel port at bottom of tank instead of on top). The fact that the fuel port is at the bottom on my tank may cause some additional fuel issues.

3. Additional fiddling with the air cleaner. The adapter that I got from 4Plus was close, but I had to use an additional spacer that I had from the Trollhole carbs that I tried. It was close, but not 100%. Still need to figure that out a little better.

4. I purchased the throttle cable from Downey which seemed to work. Not sure that is the best cable to use, as that style of cable (like a bike cable) required that the cable pull straight up on the throttle linkage as opposed to back like a GM cable would have. That required a throttle cable bracket had to be fabricated.

Nothing in the conversion was really 'hard', just a lot of things to remove/install/build.
 
fabiodaddy said:
David, I did complete the AFI install and so far the rig runs great. I still have a high idle speed (1000 RPMs) that I need to look at, but it starts right up and runs great.

Couple things I need to address:
1. High idle speed. I've contacted AFI and they have a few steps to take to adjust the idle speed. Hopefully that will work. There is also the issue that AFI doesn't use a VSS (vehicle speed sensor). Downey mentioned known issues with systems that don't use a VSS. Hopefully I can sort that out without the need of a VSS.

2. I have already run into an issue where the fuel line clogged up. I'm guessing I must have some debris in the tank that will probably become a bigger issue now that I am running an electric fuel pump at 15psi. I noticed that my fuel tank looks a little different that what I expected for a 1976 FJ40 (fuel port at bottom of tank instead of on top). The fact that the fuel port is at the bottom on my tank may cause some additional fuel issues.

3. Additional fiddling with the air cleaner. The adapter that I got from 4Plus was close, but I had to use an additional spacer that I had from the Trollhole carbs that I tried. It was close, but not 100%. Still need to figure that out a little better.

4. I purchased the throttle cable from Downey which seemed to work. Not sure that is the best cable to use, as that style of cable (like a bike cable) required that the cable pull straight up on the throttle linkage as opposed to back like a GM cable would have. That required a throttle cable bracket had to be fabricated.

Nothing in the conversion was really 'hard', just a lot of things to remove/install/build.
Click to expand...


Can you post or send me a couple of pictures? Did you look at a Howell EFI and if so why was AFI better?

Thanks
 
Dave,
Left my phone home today so can't post up any pictures (will do so tonight).

Good news, I was able to remedy the high idle last night. All it took was an adjustment of the throttle plates. They were open just a little to much. The procedure involves disconnecting the IAC and then setting the base idle. Was quite easy. So now it idles at the correct speed and in testing it did not want to stall or die at stops. I took it for a run last night and I must say the performance has never been better. Started right up this morning in 20* weather. Acceleration is much better, in fact it goes faster than I want to drive it on the freeway (65 mph just feels above the comfort level for this short, top heavy rig!!!).

I looked at several kits (including Howell). I posted on here and found that others have had good luck with AFI's kit so I went with that one. I just looked at Howells kit again and it looks very close to the AFI kit. However, the AFI kit was a bit cheaper. I was able to get the AFI kit with the ECM controlled DUI distributor for about the same price as the advertised Howell kit.

AFI kit did not include the mech. fuel pump block off plate (simple fab job). The harness was of good quality on the AFI. The hardest part of the install was getting the throttle cable installed/working. This required building a bracket on the TBI side and also modifying the gas pedal to accept the cable. Mine was old linkage style pedal.

So far I am very happy with the conversion. Only time will tell how it holds up.

Reed
 
fabiodaddy said:
Dave,
Left my phone home today so can't post up any pictures (will do so tonight).

Good news, I was able to remedy the high idle last night. All it took was an adjustment of the throttle plates. They were open just a little to much. The procedure involves disconnecting the IAC and then setting the base idle. Was quite easy. So now it idles at the correct speed and in testing it did not want to stall or die at stops. I took it for a run last night and I must say the performance has never been better. Started right up this morning in 20* weather. Acceleration is much better, in fact it goes faster than I want to drive it on the freeway (65 mph just feels above the comfort level for this short, top heavy rig!!!).

I looked at several kits (including Howell). I posted on here and found that others have had good luck with AFI's kit so I went with that one. I just looked at Howells kit again and it looks very close to the AFI kit. However, the AFI kit was a bit cheaper. I was able to get the AFI kit with the ECM controlled DUI distributor for about the same price as the advertised Howell kit.

AFI kit did not include the mech. fuel pump block off plate (simple fab job). The harness was of good quality on the AFI. The hardest part of the install was getting the throttle cable installed/working. This required building a bracket on the TBI side and also modifying the gas pedal to accept the cable. Mine was old linkage style pedal.

So far I am very happy with the conversion. Only time will tell how it holds up.

Reed
Click to expand...


Great info. Are you still doing something with the VSS?

Thanks

Dave
 
Great info - thanks. I would like to know from an AFI user if you can lug the engine down to (say) 400 RPM, in gear, without issue. You can easily do this with a carbureted FJ40.
 
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