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.

Weber 48 IDA. Accel pump issue?

Thread Tools
 
Search this Thread
 
Old 01-08-14, 08:40 PM
  #1  
Respecognize!

Thread Starter
 
Whizbang's Avatar
 
Join Date: Sep 2004
Location: Anchor Bay, CA
Posts: 4,106
Received 71 Likes on 42 Posts
Weber 48 IDA. Accel pump issue?

Okay so i have mixed many an issue with this car.

-Timing is correct
-Fuel pressure is around 3.5 psi. (gauge gets jumpy between 3 and 4 but stable higher or lower than that. no idea why). its not the pump
-Jetted per what Racing Beat wants for a 13b 6port stock engine. The carb was running on a 12a streetport for years and ran wonderfully.

The car idles odd when i play with the idle adjustment screws. And for the most part its good with medium speed acceleration enrichment. But quick stabs makes it fall flat on its face. That is with no load mind you.

Car runs great wide open above the 2300 mark.

So it seems like i need more acceleration enrichment. But frankly, i have no idea how to do that.

Could it be the needle valve? Im running a 300 that looks like the the first pic, but i do have some 330s like in the second. I frankly have no idea what the change means or does.



Old 01-08-14, 09:02 PM
  #2  
Respecognize!

Thread Starter
 
Whizbang's Avatar
 
Join Date: Sep 2004
Location: Anchor Bay, CA
Posts: 4,106
Received 71 Likes on 42 Posts
13B Engine (6-Port)
Venturi - 40mm • Fuel Jet - No. 195
Air Jet - No. 205 • Emulsion tube - F-4
Needle Valve - 300
Old 01-17-14, 06:03 PM
  #3  
Respecognize!

Thread Starter
 
Whizbang's Avatar
 
Join Date: Sep 2004
Location: Anchor Bay, CA
Posts: 4,106
Received 71 Likes on 42 Posts
still working out flat spots.

pump jet size is probably too small (50) but finding larger ones is impossible
Old 01-28-14, 10:00 AM
  #4  
Senior Member

 
rotaryengineering's Avatar
 
Join Date: Feb 2003
Location: SoCal
Posts: 331
Received 0 Likes on 0 Posts
Thumbs up You need to drill out the pump jets

Originally Posted by Whizbang
still working out flat spots.

pump jet size is probably too small (50) but finding larger ones is impossible

Do you have the screw in type of the push style? I might have some extra of both in my garage. What you described definitely sounds like a flat spot due to not enough pump shot once you crack the throttle open. If you can't find them let me know and I can drill out your existing ones or sell you a pair drilled to the correct size.
Old 01-28-14, 02:13 PM
  #5  
Blood, Sweat and Rotors

iTrader: (1)
 
DriveFast7's Avatar
 
Join Date: Aug 2001
Location: California
Posts: 3,742
Received 1 Like on 1 Post
50 is too small, 60 to 70 much better. try cleaning them out with brake cleaner first but likely they need to just be larger.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Queppa
New Member RX-7 Technical
8
09-02-18 09:53 AM
Rotospectre
New Member RX-7 Technical
3
03-28-18 03:33 PM
stickmantijuana
Microtech
30
04-23-16 06:37 PM
rotor_veux
2nd Generation Specific (1986-1992)
7
08-31-15 07:49 PM



Quick Reply: Weber 48 IDA. Accel pump issue?



All times are GMT -5. The time now is 12:00 PM.