Naturally Aspirated Performance Forum Discussion of naturally-aspirated rotary performance. No Power Adders, only pure rotary power! From the "12A" to the "RENESIS" and beyond.

Tuning 62mm Geers carb on P-port

Thread Tools
 
Search this Thread
 
Old 12-05-15, 10:53 PM
  #26  
Eats, Sleeps, Dreams Rotary

iTrader: (1)
 
ultimatejay's Avatar
 
Join Date: Nov 2006
Location: California
Posts: 4,148
Likes: 0
Received 2 Likes on 2 Posts
I had this carb in my drag rx2. I had all kinds of problems with it. Machining inside was not done correctly. There was a big metal shaving blocking the fuel ports. Fixed that then had throttle shaft problems, float problems. Just like your having I had to constantly dick around with the carb and ended up selling it and switched to EFI. I did manage 10.7 in the quarter mile. My main problem is when I would launch the car and the front end would come up the float would rise causing fuel to spill in and bog after launch. Also, would starve for fuel at the end of the quarter Mile even with an extended fuel bowl. If you want to stick with a carb then I would recommend 51 weber or Gene Berg 60. I like using f3 emulsion tubes, f65-70 idle jet, 100-130 air, 245-265 main, 44-46 chokes. You will have to play around to see what works. Also do yourself a favor and buy a good wideband so you can tune correctly and faster.
Old 12-06-15, 03:07 AM
  #27  
Exhaust Manifold Leak

 
Rub20B's Avatar
 
Join Date: Jun 2005
Location: western europe
Posts: 760
Received 18 Likes on 14 Posts
Originally Posted by ultimatejay
I had this carb in my drag rx2. I had all kinds of problems with it. Machining inside was not done correctly. There was a big metal shaving blocking the fuel ports. Fixed that then had throttle shaft problems, float problems. Just like your having I had to constantly dick around with the carb and ended up selling it and switched to EFI. I did manage 10.7 in the quarter mile. My main problem is when I would launch the car and the front end would come up the float would rise causing fuel to spill in and bog after launch. Also, would starve for fuel at the end of the quarter Mile even with an extended fuel bowl. If you want to stick with a carb then I would recommend 51 weber or Gene Berg 60. I like using f3 emulsion tubes, f65-70 idle jet, 100-130 air, 245-265 main, 44-46 chokes. You will have to play around to see what works. Also do yourself a favor and buy a good wideband so you can tune correctly and faster.
CLR annular discharge I can recommand for racing, but for street I fear transition will be hard to tune..
Old 12-16-15, 03:12 PM
  #28  
Rotary Enthusiast

iTrader: (1)
 
speedturn's Avatar
 
Join Date: Jul 2004
Location: Rocket City, Alabama
Posts: 1,035
Likes: 0
Received 2 Likes on 2 Posts
As you put in smaller and smaller venturies in a carb, then it sucks stronger, so your main jets needed to go smaller too, and your air jets needed to go larger.

Jaycee took my Weber 48IDA and machined it larger for me; this was back in 2004. I was very happy with the quality of his work. No problems at all with it after all these years.
Old 05-11-16, 12:33 PM
  #29  
Junior Member

Thread Starter
 
lacoclaina's Avatar
 
Join Date: Aug 2009
Location: Rhode Island
Posts: 20
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by ultimatejay
I had this carb in my drag rx2. I had all kinds of problems with it. Machining inside was not done correctly. There was a big metal shaving blocking the fuel ports. Fixed that then had throttle shaft problems, float problems. Just like your having I had to constantly dick around with the carb and ended up selling it and switched to EFI. I did manage 10.7 in the quarter mile. My main problem is when I would launch the car and the front end would come up the float would rise causing fuel to spill in and bog after launch. Also, would starve for fuel at the end of the quarter Mile even with an extended fuel bowl. If you want to stick with a carb then I would recommend 51 weber or Gene Berg 60. I like using f3 emulsion tubes, f65-70 idle jet, 100-130 air, 245-265 main, 44-46 chokes. You will have to play around to see what works. Also do yourself a favor and buy a good wideband so you can tune correctly and faster.

Sold the 62mm and got a 51mm from JayCee, bought an intake from Rotary Shack wich by the way was a joke, from the welding to the fitment, was able to make it work but still need to make anew one as it still wont sit flush with the engine in order to get the carb straight with the correct level, took the car to the dyno and got 235hp but ran out of time keep tunning, ended with 250 main gas 130 air, 80 idle and 120 air holder, f11 tubes. Getting a new aluminum intake fabricated by a local shop and going back with 42mm and test again, at this time I was able to get rid of the lean spot at 2k by increasing the pump jets to 60mm and using the 42mm, currently have 65 idle 100 air holder went down to 215 main gas and I think 130 air, feels good, will go back to the dyno once the new intake is completed.
Old 05-13-16, 12:03 PM
  #30  
Needs more cow bell

iTrader: (2)
 
Doc Holiday's Avatar
 
Join Date: Feb 2005
Location: Reno, NV
Posts: 833
Likes: 0
Received 3 Likes on 2 Posts
Why didn't you rev it higher?
Old 05-13-16, 12:18 PM
  #31  
Junior Member

Thread Starter
 
lacoclaina's Avatar
 
Join Date: Aug 2009
Location: Rhode Island
Posts: 20
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Doc Holiday
Why didn't you rev it higher?
I think its running out of gas, next time I go back Ill try increasing fuel pressure, was running at 4psi.
Old 05-13-16, 12:28 PM
  #32  
Junior Member

Thread Starter
 
lacoclaina's Avatar
 
Join Date: Aug 2009
Location: Rhode Island
Posts: 20
Likes: 0
Received 0 Likes on 0 Posts


New carb by JayCee.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Jeff20B
1st Generation Specific (1979-1985)
73
09-16-18 07:16 PM
The1Sun
1st Generation Specific (1979-1985)
7
09-18-15 07:13 PM
The1Sun
New Member RX-7 Technical
5
09-15-15 04:45 PM
heywier427
Naturally Aspirated Performance Forum
2
09-11-15 04:49 PM



Quick Reply: Tuning 62mm Geers carb on P-port



All times are GMT -5. The time now is 10:59 AM.