Modified carb questions...
Nikki-Modder Rex-Rodder
Joined: Feb 2001
Posts: 2,890
Likes: 14
From: Trying to convince some clown not to put a Holley 600 on his 12a.
The stock Nikki already has a built in regulator of sorts. It's not going to allow much more than about 6 psi to flow through it, depending on the year.
The built in "regulator" consists of a small hole drilled into the side of the inlet. Over-pressure goes out that hole and into the the return line.
The earlier years have slightly larger bleed orifices than the 84-85s, which corresponds to the listed pressure specs for those years (an additional .25-.5 psi, I believe).
At any rate, IMO, you are ten times more likely to be hanging up on the needle retaining clip or something of that nature than suffering from overpressure from any pump under 7 psi. The stock pump is really only good for a dependable 5 - 5.5 psi, but it's always recommended that it be changed. People think it needs to go because it's too low a pressure, but really it just needs to go due to it's age.
You'll only notice the difference between a brand new stock 5.5 psi pump and a new Carter 7 psi pump if you drive at sustained high RPMs, which many rotary enthusiasts love to do.
The built in "regulator" consists of a small hole drilled into the side of the inlet. Over-pressure goes out that hole and into the the return line.
The earlier years have slightly larger bleed orifices than the 84-85s, which corresponds to the listed pressure specs for those years (an additional .25-.5 psi, I believe).
At any rate, IMO, you are ten times more likely to be hanging up on the needle retaining clip or something of that nature than suffering from overpressure from any pump under 7 psi. The stock pump is really only good for a dependable 5 - 5.5 psi, but it's always recommended that it be changed. People think it needs to go because it's too low a pressure, but really it just needs to go due to it's age.
You'll only notice the difference between a brand new stock 5.5 psi pump and a new Carter 7 psi pump if you drive at sustained high RPMs, which many rotary enthusiasts love to do.
yep, it's true. i run a steady 6psi base pressure thru my nikki and she loves it.... what a sllluuuut! WOOOOOOOT! pressure most likely isn't your problem. start yelling at it
Originally Posted by FB II
yep, it's true. i run a steady 6psi base pressure thru my nikki and she loves it.... what a sllluuuut! WOOOOOOOT! pressure most likely isn't your problem. start yelling at it
you're a funny guy!!!
makes me laugh every time
Thread Starter
Joined: Apr 2004
Posts: 930
Likes: 7
From: Sweet Home Alabama
I looked down into the carb and both primaries and secondaries looked closed. I'll do some more "research" tomorrow. I do appreciate you all helping me out.
Does it actually idle at 6K rpm? Does it go higher if you wait? I didnt see it noticed, but has the idle speed screw been screwed in all the way? It shouldnt be. I have noticed that every single one of my carb problems so far have been because of simple things. Either a linkage getting stuck or hanging up somewhere (which is why I removed all the ones I didnt need) or a float sticking.
Sterling, I will work on the carb a bit more and see how it all goes and let you know. I am thinking about swapping floats because for some reason, the floats and needles in my old carb seem to be magic or something and never stick. I dont know, its weird. They arent really that old either. Maybe 5K miles.
Sterling, I will work on the carb a bit more and see how it all goes and let you know. I am thinking about swapping floats because for some reason, the floats and needles in my old carb seem to be magic or something and never stick. I dont know, its weird. They arent really that old either. Maybe 5K miles.
Thread Starter
Joined: Apr 2004
Posts: 930
Likes: 7
From: Sweet Home Alabama
Well...we're idling around 800 rpm now. I found the secondaries opened a little and upon further inspecion I found some bent linkage. I took the linkage off my original carb and hopefully all is well now. Sterling...when I have you work your magic on my original carb it will be missing a few items!! I hope that's ok. ;-)
I had my fuel tank sealed this last week and I intend on picking it up tomorrow. This has been a long process trying to get this car back on the road. Hopefully I'm getting close.
Thank you all for the help.
I had my fuel tank sealed this last week and I intend on picking it up tomorrow. This has been a long process trying to get this car back on the road. Hopefully I'm getting close.
Thank you all for the help.
Thread
Thread Starter
Forum
Replies
Last Post
distr0
Canadian Forum
3
Oct 7, 2015 08:17 AM





