Weber tuning Ka stuff

General Discussion about the Datsun PL510
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alexg89
Posts: 8
Joined: 24 Apr 2019 05:28

Weber tuning Ka stuff

Post by alexg89 »

Hello boys and girls

As ive read and read to the edges of the internet, i cant seem to find anyone who has shared there information about putting dual 45s on the side of a Ka24e
I how ever have started 2 threads on both Infamousnissan and Ratsun

I have a FPR set at 3-4lbs.. its an aeromotive 13301
L20b dizzy from a 78 200sx
Gm Hei ignition module for an igniter
and a 2 piece intake that was custom made and i had to have re-machined down because mating surfaces were not flat


Ive had some help along the way but when it comes to any information about tuning, jetting, and syncing no one really has had a decent answer for me except "why put carbs when you have fuel injection"
Well my harness was wrecked and what sounds better then side drafts?

Heres my issue,
Truck seems to have what feels like a "miss" and i can tell it has more room to run but i cant seem to make ends meet
i hear when it is revving back down that it sounds like its taking its time and kinda pops and backfires time to time.. what does that mean
I have yet to pull the mains out and see what size they are but that dosnt matter yet cause idk what it needs
As for idle, carbs came with 55f8s.. i put in all of the others 60,65, and 70s .. I have come back to the 60s and it seems to be "OK"

But it still feels like something isnt there.

My question is this, who has a KA with side drafts.. What are you running, what is your timing, and what plugs are you using

Ive been at this thing for like 3 weeks now and im at a loss.. Noone in my area knows ther a$$ from a hole in the ground about carbs and im kinda on my own here

https://www.youtube.com/watch?v=o10xsLpX2qI
heres a short clip of a cold start the other morning.. dont mind the wiring ill get to that when i can actually drive the truck lol

and heres a few pics of the truck
Image
Image

Thanks guys
alexg89
Posts: 8
Joined: 24 Apr 2019 05:28

Re: Weber tuning Ka stuff

Post by alexg89 »

per redline this is what comes stock in the 45 dcoe

PART # CARB. MAIN A/C IDLE E/T PUMP BYPASS CHOKE
19600.060 45-DCOE 145-145 155-155 F855-F855 F16-F16 45-45 40 36-36
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defdes
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Location: Vermont

Re: Weber tuning Ka stuff

Post by defdes »

There are some very good base line tuning/syncing write ups on Ratsun and maybe here too. You need a Unisyn for sure and the color tune plug reader is handy, or even better a wideband AF gauge. But find a write up, they might have it on the redline site too, syncing is KEY to proper function.
alexg89
Posts: 8
Joined: 24 Apr 2019 05:28

Re: Weber tuning Ka stuff

Post by alexg89 »

Ive read on how to do it and i believe im super close but this is my first go around with multiple carbs and clearly im lost lmao
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The Taterhead
Posts: 27
Joined: 17 Jun 2011 13:11
Location: Central Alabama

Re: Weber tuning Ka stuff

Post by The Taterhead »

Check into a gunson colortune. I’m pretty sure that’s what defdes is referring to. It should get you close.

https://youtu.be/osUUjJz5OCQ

Good looking truck by the way.
alexg89
Posts: 8
Joined: 24 Apr 2019 05:28

Re: Weber tuning Ka stuff

Post by alexg89 »

The Taterhead
Its funny you mention this.. i bought one this morning and it will be here tomorrow lol and thank you .. its my first truck, have had it for 15years

Been lifted, sunk in the woods, blown up, all sorts of stuff lol but its time to keep it on the road and have fun with it
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defdes
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Location: Vermont

Re: Weber tuning Ka stuff

Post by defdes »

The Taterhead wrote: 25 Apr 2019 10:47 Check into a gunson colortune. I’m pretty sure that’s what defdes is referring to. It should get you close.
Yep. Just follow the directions, disconnect your throttle cable and dial the main mixture screws in until seated then out 1 1/2-2 full turns and see where that gets you to start. The Unisyn for proper idle speed between all cylinders is still a very useful tool too.
http://sucarb.co.uk/air-flow-meter-type-bk.html
alexg89
Posts: 8
Joined: 24 Apr 2019 05:28

Re: Weber tuning Ka stuff

Post by alexg89 »

So i have a unisyn and i got them all equal.. but i was fooling around with it last night. Throttle bracket i made isnt gonna cut it because its throwing them out of sync.. so i ordered the correct top mount pull set up..

Also timing wise.. lol youll get a kick out of this.. At idle its set at 30* .. runs perfect .. fattened it up a little more because transitions werent smooth and it would stumble and flatten out with just a hair and i mean a hair of throttle... now it seems like it runs way better, did a cold start this morning and fired right off and didnt pop, miss, or act up

Color tunner thingy will be here today .. maybe ill fool around with that and see what i can figure out.. but i think she likes been fat and have all the timing
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defdes
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Re: Weber tuning Ka stuff

Post by defdes »

My experience with racing and with my FJ20 is that they do like to run on the rich side. Definitely play with the color tune, it's pretty cool but it will make you get into your jet collection.
alexg89
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Joined: 24 Apr 2019 05:28

Re: Weber tuning Ka stuff

Post by alexg89 »

Heres a picture of what i got going on so far btw

Image
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duke
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Re: Weber tuning Ka stuff

Post by duke »

My input as far as carb tuning goes is to invest in a Wideband O2 sensor. I screwed around with the side draft Mikuni's on my dual cam KA for YEARS before installing a wideband. While the colortune lets you know what is going on at idle, you have no idea what is happening under actual driving conditions. With a wideband you can monitor this and make changes that are beyond just guesses and see the results in real time. Invaluable information if you ask me.
Duke Schimmer

'72 2-Door 510
"Simplify and add lightness."
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bertvorgon
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Location: White Rock, B.C. Canada

Re: Weber tuning Ka stuff

Post by bertvorgon »

I totally concur to get a wide band for tuning!!!

It would have saved me so much time over the early years.

Then, knowing where you are at under any sustained wide open throttle is what will save your motor from detonation.

If it starts to lean out under sustained throttle, you may have fuel line VOLUME issues, so file that away should that scenario ever crop up. You may never run into a long wide open throttle scenario, but, that has bitten a few people, myself included. Lots of pressure..but, NO volume.
"Racing makes heroin addiction look like a vague wish for something salty" - Peter Egan

Keith Law
1973 2 Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1971 Vintage 13' BOLER trailer
alexg89
Posts: 8
Joined: 24 Apr 2019 05:28

Re: Weber tuning Ka stuff

Post by alexg89 »

Yah wide band is in the future.. I got my center pull throttle bracket in yesterday and hooked up ... took her for a rip and its pretttyyy sweet

Wants to buck a little bit at slow cruising but it pulls strong to about 7k.. gotta dial the rev limiter back down a little lol and then figure this low end transition shit out
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