z24i EFI, TBI, to weber carburetor conversion

Forum for the Xterra, Frontier and Hardbody, the smaller workhorses of the Nissan lineup!
Mishamoto
Posts: 2
Joined: Sun Nov 17, 2013 6:44 am
Car: 86.5 D21 4x4

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New to this site . I have been reading Frankie's posts as well as everyone else's for a while now and decided to try it on my 86 d21 4x4 when the original throttle body failed. I always hated the response , poor fuel economy, lack of power, etc.. I purchased a 38 outlaw genuine weber and began. Took about 5 hours to complete. It's a different truck. It revs quickly, has substantially greater horsepower and is smooth. I reused stock ignition and removed all emissions items including egr. Straight exhaust also.
Things I learned during the process:
1. Use Frankie's fuel system religiously! It works! The only thing I changed was using a brass restrictor in the return instead of the hose and I used a smal fuel pressure gauge directly after and coupled to the regulator.
2. The 720 intake is easier to use than the z24i drilling and tapping process. It works fine but is not as secure or clean as the z24, just a preference.
3. Set electric choke to the open position, it is a joke and I would get the manual one next time.
4. A strong return spring is absolutely necessary or you idle at 2000 rpm.
Other than that, it is better than OE for sure. If anyone is still interested in this post, I'd like to rekindle it and see what people have experienced thus far.


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Frankie Pintado
Posts: 69
Joined: Fri Jul 03, 2009 3:52 pm
Car: 2001 Nissan Frontier (sold),1987 d21 2wd, 1972 VW Karmann Ghia
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I would really like to hear about other peoples' experience as far as long-term use of this setup.

For me, this was a rough hack on a beater truck. Fact is, It worked better than anyone would have guessed but lacked any refinement. I like a lot of the modifications that others made along the way. I'm also happy to see Mishamoto went for the 38 Outlaw (do it big).

I haven't talked to Sunshine (the guy i sold my d21 to) in a few months but as far as I know the truck is still on the road. Last time I saw him he said he was having trans issues again (probably from dogging it), but it didn't sound serious and I don't know the details.
I still check on this thread once in awhile, although this project has come to a close for me. For now I'm really enjoying my new "truck", a 1985 Vanagon tin-top. If I have extra dough (like 2g's), I'm gonna experiment with Megasquirt stand-alone fuel management. I have also considered a dual Weber setup, like 48 ida's.
I still miss having a little truck that got good gas mileage, I'll probably end up buying another frontier, or d21 someday.

Mishamoto
Posts: 2
Joined: Sun Nov 17, 2013 6:44 am
Car: 86.5 D21 4x4

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Post winter update. With the severity of this years winter weather, I was fearful that my carbureted truck would not move. I was completely wrong! Even on single didget or lower it started right up! After 5-10 minutes of warmup, it ran great . I'm really impressed with the reliability of the weber carb. I couldn't have asked for an easier conversion.

On a side note. Frankie, I will be doing a Subaru EJ25 conversion on a Vanagon in the spring. We've exhausted the reliability of the vw engine and going for Japanese. I will let you know how it turns out.

ne2rk
Posts: 2
Joined: Thu Mar 13, 2014 2:51 pm
Car: 89 d21 w/ z24i carby 5spd
86.5 s12 200sx mk1.5 ca20e 5spd

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Thanks to frankie my 89 d21 w/ z24i 5spd now runs again. My truck slowly stoped starting. First day it was under 15deg it didn't start at all. If i put gas down tbi and did quick small burst of starting fluid every few seconds it ran great. Just wouldn't run by itself. so i knew it was either maf/map, injector and my ecu has burn marks inside. after a month of problem solving with ohm meter and internet forums. I was about to toss money at my tbi crap. I talked to redline they said you CAN'T put carb on tbi intake. and i was stupid if i even tryed. that i need the carb intake and dist and oil pump and rod off the 720...

So i got the weber 32/36 dfev(not dgev i wanted my throttle linkage in front) for 200bucks. made my own adapter plate. tossed old tbi butterfly on weber carb so i can keep stock throttle linkage. made a quick cable houseing stoper out of angle iron. rigged up afpr with t-fitting. got my 33.3psi down to 3.5. Removed egr and EVERYTHING under the hood i can. STARTED RIGHT UP! no problems at all! didn't even have to crank on it. I mean it popped right over!!! and idled and didn't shake or anything. cost me $250. It pulls harder. starts faster. runs super quiet. I unleashed the beast. THANKS AGAIN!

p.s. I got pictures and video of my setup i will post when i upload them to my photobucket.

InissanT
Posts: 1
Joined: Thu Mar 20, 2014 3:18 pm
Car: 1989 Nissan HB Xcab
2005 Scion xB

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I know this is an old thread, but I'm wondering if someone can tell me what weber carb kit to order, as I just acquired a HB with the Z24i motor and want to do this swap.

ne2rk
Posts: 2
Joined: Thu Mar 13, 2014 2:51 pm
Car: 89 d21 w/ z24i carby 5spd
86.5 s12 200sx mk1.5 ca20e 5spd

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old or new who cares main reason i joined this forum just to bump this thread. :) I didn't care if it was years old. I needed to thank frankie for saving my truck. I posted picture on d21 facebook page. sorry no pictures on my photobucket yet.

InissanT They don't make a kit for the z24i motor in the d21 only 720. Most people using the redline weber kit made for the older nissan 720 pickup. you can find it on ebay for $300. Redline says it can't be done! And that you need the 720's oil pump, rod and distributor. This is not true if your ecu and dist is still functional. If you order the kit you going to need to modify some stuff. Make sure you read everything you can before you go into this swap.

kcorean
Posts: 1
Joined: Thu Apr 10, 2014 7:44 am
Car: Nissan D21, Nissan 720

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There another forum posting where somebody did the same thing to a VG engine in his truck that had the TBI system - pulled the TBI - made an adapter - slapped a 4 barrel (yes a 4 barrel) on it and it worked - I assume the ECU went into backup mode and the distro simply became a centrifugal distro like it did on the z24i. Ideas?

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Frankie Pintado
Posts: 69
Joined: Fri Jul 03, 2009 3:52 pm
Car: 2001 Nissan Frontier (sold),1987 d21 2wd, 1972 VW Karmann Ghia
Contact:

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Been a while. Just checking in. I can't believe this thread has over 43,000 views. Although at least 100 of them are probably me.

My buddy just bought a 1985 Ford Fiesta with a Weber and asked me if I knew anything about them so I'm using this thread as my credentials at the moment.
My beloved d21 is long gone, but brings back many fond memories. Since this thread was started, I got married, I have bought a house, had a kid, bought and sold many vehicles, and have not really had much time to tinker with stuff like i used to. I can barely keep up with my 5 old cars. Makes me kind of sad.
That being said, I'm starting to get a serious itch. I'm looking into going back to school for electrical engineering.

Z24iswapMightyMax
Posts: 3
Joined: Fri Oct 23, 2015 6:15 pm
Car: 1986 d21/1984 ram50/1985 Mitsu mighty max. They're combined into one..Johnny cash??

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I bought a 1986 d21 today. A friend gave me his Chilton service manual for reference. I plan to use it as the donor for my mighty max/ram50 4x4, instead of throwing in a 4G63T, like the other guys do.
So I read the post on swapping tbi with a Webber carb, and I found that the "Z24i" in my truck has a distributor, rather than a crank trigger. I'll look in the service manual to verify factory application of components, or if I bought Frankenstein.
Bridging the gap: The post claims that a tbi z24 will have a crank trigger without a dizzy, but the carved version will have a vacuum advanced distributor. I'm not claiming that he is mistaken, but I'm seeing something different than what is listed and my interest has piqued. I can add pics after daybreak, to satisfy curiosity, if this IS a strange fuel/spark delivery combo.

Z24iswapMightyMax
Posts: 3
Joined: Fri Oct 23, 2015 6:15 pm
Car: 1986 d21/1984 ram50/1985 Mitsu mighty max. They're combined into one..Johnny cash??

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I was mistaken about the cas being a distributor. Also, Frankie; I don't mean to hijack your thread. However, I do intend for you to see how well or poor, a 350cfm Holly works with stock cam, etc. Also, i thank you for guidance on fuel delivery.

I did use the fuel system mod, though I installed a Holly 2300 instead of the webber (lots of pics too). For the restriction in the return line, I pushed in an emulsifier tube that holds the main-jet, left over from building my 1973 Honda CB750 bobber.

Between idle and 2k, the response is crap, but there are other issues to deal with. Response improves as I repair other systems.

The exhaust has holes from the cat to the tail pipe. The valves were not adjusted properly; some were loose, some were tight.

I adjusted valves last night, which smoothed out the idle. After the weather dries up, I'll weld up the exhaust with new pipe. Exhaust side spark plugs look text-book tan, after 431 miles btw.
On to the picture show!!

Z24iswapMightyMax
Posts: 3
Joined: Fri Oct 23, 2015 6:15 pm
Car: 1986 d21/1984 ram50/1985 Mitsu mighty max. They're combined into one..Johnny cash??

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UPTILLNOW
Posts: 1
Joined: Tue Apr 05, 2016 11:24 am

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Frankie, thanks for your information 7 years ago, and your patience with all of us converting this Z24i or VG30i to a Weber 38-DGES.
I found that REDLINE makes this Weber conversion kit # K644-38.
It is a little different than what you have presented.
They use a "By-Pass" to the tank fuel pressure regulator that is alot easier on the original fuel pump at 22psi.
REDLINE also made a bolt-up adaptor plate that will eliminate the offset mis-drilling into the manifold.
Their real Weber 38-DGES also comes pre-jetted for the VG30i and/or Z24i engines.
Again, this is an awesome thread and saved my truck.
UPTILLNOW :bowrofl:
Image
or search E-bay for K644-38

Dakotacoy
Posts: 2
Joined: Fri Dec 21, 2018 2:48 pm
Car: 1988 D21

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Hey Frankie are you still around on this forum?! And thread?!


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