I know there isn't a perfect "one size fits all" adjustment for the carb, but I know theres a good place to start from.

Right now I just have eliminated all emissions equipment (including cats). And given a good tune up(lugs, wires, oil change). I had been playing with the mixture and now my car is actually slower...

It seems like there should be a basic way to get the carb tuned for a stock car. Like screw mixture all the way down and back it out 10 turns....etc.

I thought I'd be mr tuner and turned the mixture in (leaned) until the car stumbled, then backed out one whole turn. Then adjusted the idle rpm to about 900.

The car idles great with cold start as well. (use to run really rich at cold start when it was faster). But now it lacks the power. When I floored teh car in 2nd around k before I could feel the secondarys open up and teh car would accel much faster than it does now.

Anyone have any suggestions? I have a dash dyno and could go out and play with it all day to get it perfect but I'd like a baseline to start with.

Thanks

 

if the car is basically stock, and the carb is still the stock nikki then there is no baseline. that's it already. the nikki from the factory is very well setup for what the car will do in stock form. your problem is most likely elsewhere.. what is your fuel pressure? also, try using mechanical secondaries.

 

Wel idle screw is 3 turns from bottom for a baseline, but that just for idle. If you want to tune it then you need some jets.

 

Right, but like I said I played with the stock settings on mixture and idle speed. Don't think mech. secondaries will help me that much on a stocker.



Where can I order jets for the nikki? Is that really necessary for a stock car with emissions removed? My car won't even idle if I screw the mixture al the way down and out 3 turns?

Thansk for the info!

 

if your car won't idle with only 3 turns out then i'm gonna say you have a problem eslewhere. how many turns does it take? what is your timing at?

 

Timing is at factory specs (leading and trailing) as per haynes manual? You are right about the 3 turns I was mistaken. I have it set at 3.5 turns out now. Runs great still not getting the power I was getting. I think it may have to do with the vac lines going to the distrib.? Should both of these go directly to vac? The way they were wired from the factory through the solinoids I didn't think they had a constant vac source?

 

the vaccum advance really only helps for cruising and light loads. under WOT the centrifigul advance will max out at 4,000rpms regardless.

the butt dyno is confusing sometimes. maybe you just got used to it? hahaha ORRRRR the car is now running more smoothly WHICH is making it feel more linear, instead of crappy then good which will have that "kick in the pants" feeling when it runs right at higher rpms.

kinda like big turbos feeling faster than smaller turbos at the same horsepower because it all comes in at once instead of being smooth and not throwing you back in one umph.

damnit i think i just lost myself, sorry. only way to tell if everything is good is to either get a wideband or put it on the dyno

 

Makes perfect sense to me, I'll play with the dash dyno a bit this week and see what I come up with.

Thanks!

 

Vacume leaks? They could cause this. And its 1 half turn back for the mixture. Also did you make sure you pluged that hose.... I forget what its called, its the one that connects to the idler valve thingy in the air canister. You have to plug that when you ajust the idle and stuff.

Ted

 

Your saying screw the mixture all the way in and out only a half turn? I'll try that. Seems like that would be really lean?

I was thinking more along the lines of the vac secondaries not opening at all? does the pull directly on the butter fly actrivat these or is there something else that helps them open? I removed this on the carb... would that effect anything? I thought it was the anti back fire diaphram?

 

What about poor fuel delivery to the carb? Clogged filter, tired fuel pump, etc... Or, maybe one or more of your jets is partially clogged. This happened to me with the secondary jets, and the car would go faster if I gave it less throttle, but totally dump if I gave it too much throttle. Good luck with it.

 

whoaaaa, you removed that diahpram and didn't go with mechanical secondaries??? that is the vaccum secondary box. just do the mechanical mod. it's written all over this site, just search. yea that can make a big difference LOL

 

LOL... Whoops! I thought the haynes manual said something about that being an after fire diaphram.

Thanks!

 

it's all good, i learn the hard way on these cars too. hahahaa

 

haha, yeah removing that would defenitely do it.

I drew a red arrow pointing to where the anti-afterburn valve should/used to be. So dont worry its already gone.

 

Yup that sure made a difference! Car doesn't idle as good now though. Also after it's warm if I shut it off it's a bear to start? Seems odd installign that diahram would change any of that? Ah well got one problem fixed anyway!

 

it's possible that when you put the vaccum arm back on it got stuck in postition to where it's leaving the secondaries always open a hair. this would cause it to throw off the idle and possibly pull extra fuel in under cranking. look down the carb and make sure the secondaries are completely closed at idle/ off.