83 720 pick up, new and need help

1980-1986 Datsun 720 forums. All 720-specific topics and discussion can be found here.
Posts: 2
Joined: Sat Apr 14, 2007 9:18 pm
Car: 1983 720 Pickup ST Z24/5spd sunroof, tach, clock, oil and volt meter, a/c, p/s, p/b, carburated, sin

83 720 pick up, new and need help

Postby 83z24 » Sat Apr 14, 2007 10:03 pm

Hi, im new here and im hopeing yall can help me. Ive got a '83 720. bought it from a friend for $200. It ran good with a few bumps along the way. but really needed a transmition.

What it is:1983 720 Pickup, single cab, swb. carburated z24 8 plug motor, 5spd trans. produced 7/1983, 193000 mi. 2wd

What ive done:

A complete tune-up. air filter, 8 plugs, wiers, cap, rotor, pcv, fuel filter, oil presure switch, powersteering presure line, new front rotors, alternator, and tires. ive even run a few cans of seafoam through it.

Question 1:

when i gave the truck a tune up, i took off the two emission tubes from the air box, being new to these trucks i figured it would give me a little extra hp. however it ended up causeing me some problems, horrible exhaust leak, and a very noticeable loss of torque. ive since plugged those lines and my exhaust leak and torque went back up but still sluggish. I want to get a header and exhaust, and take all of the emissions, includeing the catalitic converter, off the truck to gain more hp as well as eleminate my problems all in one fail sweep.

Would a header solve my problem, and would it jump my hp and torque up? How about mpg?

Question 2

The choke cam in the oem carb got stuck so the choke was always closed and it ran super rich all the time, ive since wired the choke open and other than being hard to start when the motor is cold it doesnt run so rich.

Ive had an idle problem, it has seemed to want to die every time i depress the clutch. Ive played with the idle ajustment screw and it idles now, but it has a high idle. I feel that i have just coverd the problem up rather than fix it, and i dont like to do that. Everyone i have talked to, has advised me to get rid of the original hitachi carb, and go webber.

Is this a simple fix? I want to get a webber carb for it for hp etc., would this be the right way to go? would this increce my hp? mpg?

Question 3:

The 5 speed in the truck is missing 5th gear, all the syncros are bad and here recently the gear that drives the speed-o has failed. Ive bought a new speed-o cable and had the speed-o tested and they work fine, so it must be in the transmition. 1st gear works fine, but has a tendency to pop out of gear, 2nd gear grinds bad when shifting and also has a tendency to pop out, 3rd gear grinds when shifting, and 4th gear works great, 5th gear does not enguage at all, but you can hear it ratteling around in the case.

I know i need a new transmition. Ive heard that the early 80's 280zx turbo 5spds will bolt up and have better gear ratios as well. How true is this??? are there any mods i would have to do? What year 5spds would fit this truck?? trying to find one in a salvage yard is a pain for an import this old!!!!!!!!! PLEASE HELP!!!

Question 4:

Thanks in advance!!! My end goal is to make this a little street truck. and i really think this motor is capable of that! The motor is still really strong, and i think has alot of umph left in it. But i think the carb, imitions, and transmition are really slowing it down.

what do yall think?

Thanks again!


Posts: 2
Joined: Sat Apr 14, 2007 9:18 pm
Car: 1983 720 Pickup ST Z24/5spd sunroof, tach, clock, oil and volt meter, a/c, p/s, p/b, carburated, sin

Re: 83 720 pick up, new and need help (83z24)

Postby 83z24 » Tue Apr 17, 2007 7:02 am

is there anyone who can help? ive looked through the datsun forum, and i cant find a whole lot on these trucks or motors. Can anyone help me???????????


Posts: 4
Joined: Tue Oct 17, 2006 3:48 pm
Car: nissan 720 pickup

Re: 83 720 pick up, new and need help (83z24)

Postby ocula720 » Mon Jun 18, 2007 4:07 pm

i know a fair amount about these trucks.

first lets figure out what you disconnected. the hitachie carb needs many of the things connected to it and are not just emissions. besides removing emission stuff really just ****s up the enironment and will not help performance in anyway. The egr could possibly cool down over all temp but thats about it. the stock things on every engine are desiged to work together so they are all needed. There are some ****ed up emission **** on there that you can remove though but only if you have a weird model truck. like the the ones for high altitude have stuff thats uneeded if your not at a high altitude. i say put everything back together and then see if that solves some problems.

yes you can get a weber and they are easy to put on. if you want crazy hp/trq gain go with the 38


nis720 told me that he beat a 5.0l mustang and broke motor mounts because thats how insain the hp/trq gain was. even if the mustang thing is untrue the gain is alot with these carbs for sure but he also told me he was getting 10mpg, OUCH!

the option i plan to use is putting on this carb.


great gain and if tuned right you will receive higher mpg.

here is what alot of people do.

if your engine has many miles on it then do a rebuild. this alone with gain you added power if the engine is old and warn out. also change tranny and diff fluid. when rebuilding it its your choice to shave the head or bore it out. this will lower mpg though.

always do exhaust before large intake modifications such as a weber. dough thorly makes a good header also i hear the headers on 4x4parts.com are really good and way cheaper then a dough thorly.then exhaust should be about 2.2inch to either no cat or a highflow one then your choice of muffler or be a ricer a straight pipe it.

then add the webbber of your choice. or if you want **** gas milage add mikuni side draft carbs. these carbs with blow your socks off if tuned right.

make sure your cooling system is working well (before carb).then get and electric fan. I hear the 16inch S-blade style cools the best.

after this you can get the HB223B rear end and add an LSD for good traction. or just weld your diff. i would also switch to a single drive shaft.

as for your tranny problem. you either get a really exspensive rebuild or do the 280zx tranny. many other transmissions bolt to the z24. the zx tranny is less common and i know the 240sx (single cam) tranny bolts up also. all you need is the tranny (new clutch is a good idea also get a throwout bearing) and maybe a drive shaft.

ive seen so many different things done to these trucks so if you need more options just ask. you could always do a ka24e swap and gain a good amount from that also. even just stock.

any pics of what was disconected would help.

if you have more questions ask.

Posts: 6
Joined: Tue Feb 06, 2007 11:22 pm
Car: 84 Nissan

Re: 83 720 pick up, new and need help (83z24)

Postby Nassin671 » Sun Jul 29, 2007 12:12 am

What you need to make the Z24 motors moveHKS dual intake manifold w/ 44mm Mikuni sidedraftsCower cam w/ a big liftKA24E Fidanza Aluminum flywheel Part# 143241, Center force 2 clutch4.38 or 4.88 gearing from the 1969 to 1979 older Datuns trucks.Long neck tranny from the datsun Z's cars and all you need to do is just swap out the bell housing.MSD 6AL ignition box w/ MSD blaster 2 coilsHooker or Dough Thorely headersHere some pics. Later! Jes

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