Holley Sniper issue - Chevelle Tech
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post #1 of 25 (permalink) Unread Nov 17th, 19, 1:30 AM Thread Starter
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Kurt
 
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Holley Sniper issue

Sniper lovers.... I need help ....
I just got my '66 finished and home last week ....
Driving it with the "out of the box" 1:1 throttle linkage,
it's just about impossible to launch it ....Canít feather
the throttle for a tire saving take off .... (TKO 600)
Runs great after that ....
I bought a progressive link that brings the secondaries in
after the primaries are open +-40% ....
Problem is, the vacuum ports are fed by the secondaries...
So, no vacuum until they are open .....But, I can upgrade the
distributor to get rid of the vacuum advance ....

But, the question is, where do I get vacuum for the brake booster ??

1966 Black/Red SS coupe .....
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post #2 of 25 (permalink) Unread Nov 17th, 19, 2:27 AM
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Justin
 
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I have the progressive linkage and have my brake booster running to the back of my sniper. Everything works just fine

1974 chevelle with 73 laguna nose sbc 357 Brodix IK180 heads Comp Cams XE274H Edelbrock RPM airgap 650 AED double pumper, M20 muncie, Truetrac with 3.73s
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post #3 of 25 (permalink) Unread Nov 17th, 19, 9:38 AM
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Allen
 
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Re: Holley Sniper issue

Quote:
Originally Posted by thebeast View Post
Sniper lovers.... I need help ....
I just got my '66 finished and home last week ....
Driving it with the "out of the box" 1:1 throttle linkage,
it's just about impossible to launch it ....Canít feather
the throttle for a tire saving take off .... (TKO 600)
Runs great after that ....
I bought a progressive link that brings the secondaries in
after the primaries are open +-40% ....
Problem is, the vacuum ports are fed by the secondaries...
So, no vacuum until they are open .....But, I can upgrade the
distributor to get rid of the vacuum advance ....

But, the question is, where do I get vacuum for the brake booster ??



Interesting, just goes to show that different set-ups and people want different things. There is a recent thread where someone is converting the Edelbrock PF from progressive to 1 to 1 because the progressive didn't have the throttle response he was used to/wanted.



As for vacuum, if the provided ports don't work you could use a spacer with a port or use a port directly from the intake. Good time to switch to a controlled distributor (assuming the Sniper has provisions for it), I went with the GM small cap controlled by my Holley Terminator. It's handy to change timing and curve with a few key strokes; really lets you dial in what the car wants with minimal effort.
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post #4 of 25 (permalink) Unread Nov 17th, 19, 10:49 AM
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Claude
 
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Re: Holley Sniper issue

Quote:
Originally Posted by thebeast View Post
Sniper lovers.... I need help ....
I just got my '66 finished and home last week ....
Driving it with the "out of the box" 1:1 throttle linkage,
it's just about impossible to launch it ....Canít feather
the throttle for a tire saving take off .... (TKO 600)
Runs great after that ....
I bought a progressive link that brings the secondaries in
after the primaries are open +-40% ....
Problem is, the vacuum ports are fed by the secondaries...
So, no vacuum until they are open .....But, I can upgrade the
distributor to get rid of the vacuum advance ....

But, the question is, where do I get vacuum for the brake booster ??
Do you mean that it has too much throttle response Funny 'cause most guys are hoping to have more! Öbut maybe it's more "touchy" with a manual transmission, I dunno.

1971 Chevelle SS
1987 Buick Grand National 9.48 @ 142 mph
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post #5 of 25 (permalink) Unread Nov 17th, 19, 12:20 PM Thread Starter
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Kurt
 
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Re: Holley Sniper issue

Thanx for the input .... Yes, itís the "touchiness" that makes the car hard to get off the line ...
Since Justin didnít have a problem, Iíll go ahead and install the link, tell the hand-held I did
it, and see what happens ...
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1966 Black/Red SS coupe .....
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post #6 of 25 (permalink) Unread Nov 17th, 19, 12:51 PM
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Justin
 
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It’s not necessarily the throttle response for me, it was that the pedal was so stiff, it was hard to gauge how much throttle to give it. especially with a manual car.
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1974 chevelle with 73 laguna nose sbc 357 Brodix IK180 heads Comp Cams XE274H Edelbrock RPM airgap 650 AED double pumper, M20 muncie, Truetrac with 3.73s
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post #7 of 25 (permalink) Unread Nov 17th, 19, 3:21 PM Thread Starter
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Kurt
 
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Re: Holley Sniper issue

Quote:
Originally Posted by JF74chevelle View Post
Itís not necessarily the throttle response for me, it was that the pedal was so stiff, it was hard to gauge how much throttle to give it. especially with a manual car.
I need to clarify..... Mine is too stiff, also ..... "touchiness" was the wrong description....

1966 Black/Red SS coupe .....
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post #8 of 25 (permalink) Unread Nov 17th, 19, 11:10 PM
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Jason
 
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Re: Holley Sniper issue

Quote:
Originally Posted by thebeast View Post
I need to clarify..... Mine is too stiff, also ..... "touchiness" was the wrong description....

For a stiff, touchy pedal try putting the throttle cable ball higher up on the linkage to make it easier to move.
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post #9 of 25 (permalink) Unread Nov 17th, 19, 11:25 PM Thread Starter
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Kurt
 
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Re: Holley Sniper issue

Quote:
Originally Posted by JB SS 396 View Post
For a stiff, touchy pedal try putting the throttle cable ball higher up on the linkage to make it easier to move.
Iím using a rod instead of a cable .... itís hooked as high as itíll go ...

1966 Black/Red SS coupe .....
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post #10 of 25 (permalink) Unread Nov 18th, 19, 1:57 AM
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Justin
 
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Raise up the throttle linkage, that helped a ton too

1974 chevelle with 73 laguna nose sbc 357 Brodix IK180 heads Comp Cams XE274H Edelbrock RPM airgap 650 AED double pumper, M20 muncie, Truetrac with 3.73s
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post #11 of 25 (permalink) Unread Nov 18th, 19, 9:46 AM
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Jimmy
 
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Re: Holley Sniper issue

Quote:
Originally Posted by thebeast View Post
Iím using a rod instead of a cable .... itís hooked as high as itíll go ...
This will fix the stiff throttle linkage. https://www.efisystempro.com/sniper/...ter-lever-1952

Twin Turbo 400 SBC 748 RWHP in 1969 Chevelle.
Sniper EFI,Turbo 400, Victor Jr. CNC heads and 2925 Super Victor Manifold.
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post #12 of 25 (permalink) Unread Nov 18th, 19, 10:21 AM
 
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Re: Holley Sniper issue

Quote:
Originally Posted by Yukon0724 View Post
This will fix the stiff throttle linkage. https://www.efisystempro.com/sniper/...ter-lever-1952
This will do the trick. Make sure you follow the setup instructions. Easy to install but you need to use the handheld and set the throttle position telling the sniper exactly what throttle position the secondaries start to open with the link installed.
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post #13 of 25 (permalink) Unread Nov 18th, 19, 12:03 PM
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Steve
 
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Re: Holley Sniper issue

Quote:
Originally Posted by Blown1932 View Post
Interesting, just goes to show that different set-ups and people want different things. There is a recent thread where someone is converting the Edelbrock PF from progressive to 1 to 1 because the progressive didn't have the throttle response he was used to/wanted.
That was me. I decided not to convert the Edelbrock progressive linkage throttle body to 1:1 throttle linkage. I used the FiTech Go Port 1:1 throttle linkage throttle body I had after modifying it so that it worked with the sensors Edelbrock uses. It's a 900cfm throttle body. Car runs great.

I also lightened up the spring pressure on the throttle body throttle linkage. It's easy to modulate throttle input with less spring pressure. I don't feather my starts with a little 400HP SBC and an automatic unless the roads are wet. Darn one legged rear end and my cheap tires don't hook up that well on a wet road.

Brake booster port is below the throttle blades on the Sniper and full time manifold vacuum. Ported vacuum for a vacuum advance is above the blades. There should be another small full time vacuum port on the Sniper.
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post #14 of 25 (permalink) Unread Nov 19th, 19, 1:06 PM
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sam
 
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Re: Holley Sniper issue

When I first installed my sniper, it did the same thing. Drive it for a while and allow it to tune and it will calm down. Mine has, without any modification.

1967 Royal Plum, 434BB, AFR Heads, 3.90 gears, New Chris Straub Hyd Roller!, 200r4
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post #15 of 25 (permalink) Unread Nov 19th, 19, 1:28 PM Thread Starter
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Kurt
 
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Re: Holley Sniper issue

Quote:
Originally Posted by scalise71 View Post
When I first installed my sniper, it did the same thing. Drive it for a while and allow it to tune and it will calm down. Mine has, without any modification.
Itís almost impossible to drive it now, being a clutch car ....
A rear-ender waiting to happen ....
I have a throttle extension coming ..... Iím trying that
first, before going to progressive ....

1966 Black/Red SS coupe .....
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