79 350 with nitrous?
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79 350 with nitrous?
hey guys, i am restoring my 79 vette, i'm taking a 350 motor out of a 77 vette parts car i have and i'm installinga borg warner 4 speed tranny, and i just got a edelbrock nitrous kit #70001.. has anyone had any experience with this kit and the performance upgrade? can my motor handle this? i was just thinking of spraying a 50 shot for now, i just want to put it on the car for those "once in a while" kicks. thanks
Frank
Frank
Le Mans Master
Joined: Jul 2005
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From: Austin Texas
I'll guess that cuz the primaries are so small, and has an equally small accelerator pump shot, that the motor may have a problem with mixture till the secondaries open up...especially if the secondaries are lazy (some are calibrated to not fully open till over 7000 rpm).
Race Director
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From: FL
Originally Posted by greyghost79
what problems, if any, are there with using nitrous with a Q-Jet? i've been told you shouldn't use nitrous on a carb with vacuum operated secondaries. any truth to this?
Two things:
1) Most people hook the nitrous up to a microswitch on the throttle linkage so it only activates at max throttle. By then, your secondaries should be open.
2) Q-Jets aren't vacuum secondary carbs. They have mechanical secondaries and an spring loaded air valve that opens with demand. The airvalve solves the problem of no accelerator pump on the secondary side and helps responsiveness.
Pro
Joined: Mar 2005
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From: James Island South Carolina
This is a fun article in Chevy High Performance magazine about nitrous and a stock 350:
http://www.chevyhiperformance.com/te.../148_0303_n20/
http://www.chevyhiperformance.com/te.../148_0303_n20/
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From: FL
Originally Posted by 19silver78
That's wrong. The QJet that he's working with has vacuum operated secondaries.
No Quadrajet as built by Rochester or Carter has vacuum operated secondary throttle plates. The linkage that opens the throttle plates (in the bottom plate of the carb) is mechanically connected to the primary throttle plates. The only thing that stops the secondaries from opening is the choke.
The air valve door may have a vacuum break on it to help control the rate of opening. The air valve door is the spring loaded door on the top of the carb that opens when there is enough demand.
Small picture, but if you look closely, you can see the mechanical secondary thottle linkage extending back from the primary throttle shaft to the secondary throttle shaft. On the other side of the carb, just in front of the choke, you can barey make out the vacuum break can that controls the opening rate of the secondary air valve.
Blatantly plagarized from http://www.442.com/oldsfaq/ofcrb.htm:
Witness, for example, GM's usage of them on 307's, and 305's. The secret is in the small primaries (smaller than the primaries in a 600 CFM Holley) which optimize low and mid range. The secondaries are important, as well, in the Q-Jet's applicability to engine sizes that, according to the CFM charts, are way too small for the Q-Jet's CFM rating. The key here is in the mechanically operated throttle and the air valve that responds to engine demand, and is not directly linked to the secondary throttle. The fuel flow in the secondaries responds to air valve position, not secondary throttle position. These features make the secondaries, in theory, very much like a variable-venturi carburetor.
Last edited by SteveG75; Sep 21, 2005 at 10:30 PM.
Maybe Lars can settle the dispute?
Drifting
Joined: Nov 2004
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From: Longwood Florida
You can safely run 100 shot on bone stock 350... with proper fuel and timing retard. You could push it to 150 shot... with proper fuel and timing retard... NO MORE THAN that though.
50 shot you will not even feel it. you ET or mph will be slightly better though.
SPRAY THAT 100 or 150... Yeah BABY!!!
50 shot you will not even feel it. you ET or mph will be slightly better though.
SPRAY THAT 100 or 150... Yeah BABY!!!
Melting Slicks
Joined: Jul 2005
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From: 406ci SB, AFR 180 Heads - 490 HP @5,600 RPM 529 lb-ft @ 4,100 RPM
Originally Posted by badboyr6
no i dont have that carburator, i have a stock holly... well i was think of do 50 shot 4 now, but i have the jets for 75 and 100... i guess we will see what happens....
New Post... Lookin for a stock 350
Drifting
Joined: Nov 2004
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From: Longwood Florida
Originally Posted by badboyr6
i think i'm going to sell the nitrous system.... um, does anyone want a brand new edelbrock nitrous system? 
Does the kit have instructions?? If so I am sure you can handle it... if you motor is stock and in good working order... your 50 shot will not hurt your motor.
NO2 is the most fun you can have with your clothes on!
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yes, the kit has intructions, its brand new, i was just going to put the 50 shot and see how i like it... also, it does include the microswitch for the carb, and the togle activation switch.. i'll let you guys know, how it works out!