2nd Generation Specific 1986-1992 Discussion

Rb Holley 4-barrell Setup

Thread Tools
 
Search this Thread
 
Old 06-11-2004, 05:43 PM
  #11  
Super Moderator
 
Rob x-7's Avatar
 
Join Date: Feb 2002
Location: Amityville, New York
Posts: 12,288
Default

Originally Posted by 83turbo' date='Jun 11 2004, 08:29 AM
Make sure the secondaries are working. I read (I think on the evil forum) that someont had a problem with this.

You can unhook the secondary linkage and see if it loses power, or put a screw in the linkage to force the secondaries to open.
he might have a 600 vacuum secondaries, only a 600 double pumper

would have linkage for the secondaries



might sound silly- but are you sure the carb is fully open at WOT?
Rob x-7 is offline  
Old 06-11-2004, 05:44 PM
  #12  
Senior Member
 
j9fd3s's Avatar
 
Join Date: May 2002
Location: California
Posts: 22,465
Default

Originally Posted by Seraphx7' date='Jun 11 2004, 08:33 AM
Let alone a carbed one? a carb is the best way to get power from a N/A.
the same size carb will always be down on power than the same size efi, becase the carb has to have a venturi. also efi can be tuned for a broader range, so it usually will make better power off peak than the carb
j9fd3s is offline  
Old 06-11-2004, 05:47 PM
  #13  
Super Moderator
 
Rob x-7's Avatar
 
Join Date: Feb 2002
Location: Amityville, New York
Posts: 12,288
Default

it seems that most of the people who modify NA RX7s always

go carb to keep it simple I guess



so that maybe that is the reason why its thought to make more

power?
Rob x-7 is offline  
Old 06-11-2004, 06:32 PM
  #14  
Senior Member
 
marcus7's Avatar
 
Join Date: Mar 2004
Posts: 172
Default

Originally Posted by Seraphx7' date='Jun 11 2004, 08:33 AM
Let alone a carbed one? a carb is the best way to get power from a N/A.
Based on every class of motor racing I’ve ever seen, I would have to disagree. If EFI is allowed, any team with money immediately ditches the carburetor.
marcus7 is offline  
Old 06-11-2004, 07:03 PM
  #15  
Senior Member
 
venomrx7's Avatar
 
Join Date: Dec 2003
Location: Mississippi
Posts: 464
Default

fuel injection is by far superior. power and tuning wise.



why do you think jegs has 3000 dollar injection systems for old skool chevys? it makes more power than carb.



carb is just simpler, not better. stick with fi.
venomrx7 is offline  
Old 06-12-2004, 12:14 PM
  #16  
Senior Member
 
j9fd3s's Avatar
 
Join Date: May 2002
Location: California
Posts: 22,465
Default

Originally Posted by Rob x-7' date='Jun 11 2004, 02:47 PM
it seems that most of the people who modify NA RX7s always

go carb to keep it simple I guess



so that maybe that is the reason why its thought to make more

power?
its simple and usually larger, makes more power that way
j9fd3s is offline  
Old 06-12-2004, 02:49 PM
  #17  
Senior Member
 
83turbo's Avatar
 
Join Date: Nov 2003
Posts: 480
Default

Originally Posted by Rob x-7' date='Jun 11 2004, 02:43 PM
he might have a 600 vacuum secondaries, only a 600 double pumper

would have linkage for the secondaries



might sound silly- but are you sure the carb is fully open at WOT?
I'll try to clarify - the "linkage" I meant to is really more of an actuator

rod coming from the secondary vacuum pod. Looking at a Holley, I also see that

if you unhook this to disable to secondaries, it is also necessary to wire the

secondary throttle shaft closed as there is no other spring. Then you just

drive an note any power loss. If you don't see any difference, the secondaries

weren't working to begin with.

The other secondary linkage present on a vacuum secondary carb is the lockout

that prevents the secondaries from opening before the primaries are open far

enough. You can stick a screw in this one and thus make it force the secondaries

to open (rather than just limiting when they can open). It's a rig, but

makes for a useful test. If the car now has more power, you've got a problem

such as a bad diaphragm (these get torn all the time when the vacuum pod

is reassembled from a spring change due to the cheap nature of the diaphragm).
83turbo is offline  
Old 06-12-2004, 04:55 PM
  #18  
Senior Member
 
venomrx7's Avatar
 
Join Date: Dec 2003
Location: Mississippi
Posts: 464
Default

holley's are too much trouble, get a demon or edelbrock. not too much more, and loads better.
venomrx7 is offline  
Old 06-13-2004, 01:58 PM
  #19  
Super Moderator
 
Rob x-7's Avatar
 
Join Date: Feb 2002
Location: Amityville, New York
Posts: 12,288
Default

Originally Posted by 83turbo' date='Jun 12 2004, 03:49 PM
I'll try to clarify - the "linkage" I meant to is really more of an actuator

rod coming from the secondary vacuum pod. Looking at a Holley, I also see that

if you unhook this to disable to secondaries, it is also necessary to wire the

secondary throttle shaft closed as there is no other spring. Then you just

drive an note any power loss. If you don't see any difference, the secondaries

weren't working to begin with.

The other secondary linkage present on a vacuum secondary carb is the lockout

that prevents the secondaries from opening before the primaries are open far

enough. You can stick a screw in this one and thus make it force the secondaries

to open (rather than just limiting when they can open). It's a rig, but

makes for a useful test. If the car now has more power, you've got a problem

such as a bad diaphragm (these get torn all the time when the vacuum pod

is reassembled from a spring change due to the cheap nature of the diaphragm).
why not peek in the carb, open the throttle all the way and see if there

is gas coming out of the secondaries?
Rob x-7 is offline  
Old 06-13-2004, 02:40 PM
  #20  
Senior Member
 
83turbo's Avatar
 
Join Date: Nov 2003
Posts: 480
Default

Originally Posted by Rob x-7' date='Jun 13 2004, 10:58 AM
why not peek in the carb, open the throttle all the way and see if there

is gas coming out of the secondaries?
Engine needs to be under a load for the secondaries to really open. In neutral

they will barely move at all. They may open visibly if you rev the crap out

of it.
83turbo is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
rotayt
Rotary Engine Building, Porting & Swaps
3
09-14-2009 07:26 AM
Aurosting
RX-7 & RX-8 Parts For Sale & Wanted
4
02-04-2007 02:30 PM
Lt. Dan
RX-7 & RX-8 Parts For Sale & Wanted
4
09-19-2006 07:39 PM
RX7CMS
1st Generation Specific
11
06-25-2004 11:54 AM
sgieldon
1st Generation Specific
21
01-22-2003 09:17 PM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


Quick Reply: Rb Holley 4-barrell Setup



All times are GMT -5. The time now is 08:43 PM.