Gross Jets in a Nikki 4
#1
Senior Member
Thread Starter
Join Date: Nov 2001
Location: Gig Harbor, WA
Posts: 566
Likes: 0
Received 0 Likes
on
0 Posts
Gross Jets in a Nikki 4
81 RX-7, rebuilt motor less than 1000 miles. Car was in storage for quite some time. Pulled it out and rebuilt the carb. Was having problems left and right with too much gas (gas was coming in through the primaries and secondaries with just the key on) Adjusted float level at least a hundred time (thats what my wife tells me anyway) Had the car running good but was too rich and performance was getting worse. Got discusted with whole operation, ordered new floats and some gross jets, now car idles great! But when putting foot into it, it tends to sputter and spit especially at high rpm 5000+. Fuel filter new, fuel pump pumping, no vent problems, spark good. Any ideas???? Please help. Im not sure if adjusting idle mix and air mix is the trick, but hey, I'll try anything. Does anyone know the proceedure for an 81, Haynes manual criptic and unsuccessfull. Is it the same for an 84-85? Please help.
#3
Senior Member
Thread Starter
Join Date: Nov 2001
Location: Gig Harbor, WA
Posts: 566
Likes: 0
Received 0 Likes
on
0 Posts
Is the measurements for gross jets the same as stock needles. I have both floats dead on, it just seems that its giving too much gas, Ill floor it and it sputters and when I let off it surges forward as if it had the right amount. Too much or too little is the q????
#4
Junior Member
Join Date: May 2001
Location: Grand Rapids, MI, USA
Posts: 29
Likes: 0
Received 0 Likes
on
0 Posts
Check out Paul Yaw's site, he's a Nikki race carb builder/researcher who has much to teach.
http://personal.riverusers.com/~yawpower/
If I can't afford to stuff a T2 motor into my Project, I'll be getting my carb from him.
http://personal.riverusers.com/~yawpower/
If I can't afford to stuff a T2 motor into my Project, I'll be getting my carb from him.
#5
Rotary Freak
Join Date: May 2001
Location: Peoria, IL
Posts: 1,779
Likes: 0
Received 0 Likes
on
0 Posts
A couple of things:
1. Make sure that when you rebuild the carb that you didn't put the float needle "springs" in, unless your old carb had them. The kit will include them, put unless you used to have them they are not only unnecessary, but guess what? They will cause your bowls to overfill and start pumping gas into the barrels with just the key turned on.
2. I have heard very bad things about the Grose jets, just second hand knowledge, nothing first hand. So take it with a grain of salt.
3. (I said a couple of things didn't I?) Your problem could be starvation at 5k rpm. At idle are your fuel levels in your float bowls exactly halfway? The other possibility is the accelerator pump, but I would put my money on starvation.
hope this helps,
hanman
1. Make sure that when you rebuild the carb that you didn't put the float needle "springs" in, unless your old carb had them. The kit will include them, put unless you used to have them they are not only unnecessary, but guess what? They will cause your bowls to overfill and start pumping gas into the barrels with just the key turned on.
2. I have heard very bad things about the Grose jets, just second hand knowledge, nothing first hand. So take it with a grain of salt.
3. (I said a couple of things didn't I?) Your problem could be starvation at 5k rpm. At idle are your fuel levels in your float bowls exactly halfway? The other possibility is the accelerator pump, but I would put my money on starvation.
hope this helps,
hanman
#6
Administrator
iTrader: (8)
Join Date: Nov 1998
Location: So. Arlington, TX!!!
Posts: 12,974
Likes: 0
Received 59 Likes
on
36 Posts
I tried the Grose jets but couldn't get them to seat the needles against the pressure of an unregulated Facet fuel pump. They kept filling the bowls completely. I gave up and threw the stock jets (new ones that came with the rebuild kit, of course...) back in and had to bend back the float tabs to get the bowls to fill half full. It would have been nice if they had come w/some instructions but they're sent as is by Mazdatrix in a little envelope. Speaking of Paul Yaw, is the Email URL good? Does he always ignore repeated attempts to communicate through his Email? Been about a month since I sent him my second Email requesting pricing on a custom carb job.
#7
Rotary Freak
Join Date: May 2001
Location: Peoria, IL
Posts: 1,779
Likes: 0
Received 0 Likes
on
0 Posts
Mar3
Paul doesn't ever answer his emails. Try calling him in the morning, AZ time. Otherwise, check the mazspeed site and do a search for Yaw, and hanman. I posted the most recent pricing for his carbs. Remember, you will also be purchasing a new fuel pump, regulator, pressure gauge, and porting of the manifold.
If you can't find the post email me, I have the prices somewhere.
hanman56@yahoo.com
Paul doesn't ever answer his emails. Try calling him in the morning, AZ time. Otherwise, check the mazspeed site and do a search for Yaw, and hanman. I posted the most recent pricing for his carbs. Remember, you will also be purchasing a new fuel pump, regulator, pressure gauge, and porting of the manifold.
If you can't find the post email me, I have the prices somewhere.
hanman56@yahoo.com
Trending Topics
#9
Administrator
iTrader: (8)
Join Date: Nov 1998
Location: So. Arlington, TX!!!
Posts: 12,974
Likes: 0
Received 59 Likes
on
36 Posts
Hanman, what's the URL for your website? And what's the point of an Email address if not to communicate? Whadup wit dat? I haven't gone back to the site for the phone number but I'll give it a shot on Saturday. My particular problem is this. I've already got a Facet fuel pump which is supposed to be good to about 200 horse or so, already got the street-ported 12A and the manifold was ported with the engine rebuild by Ari at RP in Garland. What I was asking about (remember I Emaild about a custom carb job...) was an attempt to build a big Nikki with emissions tubes and ports intact for street use. Here in the Metroplex, the ***** expect compliance and my favorite inspection guy was drummed out of business. Granted, I only have to worry about this for 3 more years and then it'll become an antique subject only to safety guidelines but I don't want to be a gross polluter at the same time. I think I'll start a different thread on the subject since I haven't gotten anything productive from the Yawpower side of things...
Thread
Thread Starter
Forum
Replies
Last Post
Jeff20B
1st Generation Specific (1979-1985)
73
09-16-18 07:16 PM