C4 Accelerator Pedal Question
Thread Starter
Le Mans Master
Joined: Aug 2000
Posts: 6,273
Likes: 14
From: Austin TX
C4 Accelerator Pedal Question
All,
I have a '70 Vert with a 90 Tuned port 383. The OE accelerator pedal is not giving me full throttle - when the pedal is floored, I'm only getting about 40% throttle body blade opening.
So, I'm thinking that I need to install an accelerator pedal assembly from a 90 +/- C4.
Can someone please send me a pic or assembly manual page of the C4 accelerator pedal so I can figure out if this is the answer and how to install it.
Thanks mucho.
I have a '70 Vert with a 90 Tuned port 383. The OE accelerator pedal is not giving me full throttle - when the pedal is floored, I'm only getting about 40% throttle body blade opening.
So, I'm thinking that I need to install an accelerator pedal assembly from a 90 +/- C4.
Can someone please send me a pic or assembly manual page of the C4 accelerator pedal so I can figure out if this is the answer and how to install it.
Thanks mucho.
Thread Starter
Le Mans Master
Joined: Aug 2000
Posts: 6,273
Likes: 14
From: Austin TX
Burning Brakes
Joined: Apr 2004
Posts: 762
Likes: 2
From: Huntington ma
Is that '70 a cable throttle linkage or a mechanical? Sorry, I don't know, offhand.
Reason I ask is that I have a TPI setup in a '78 pickup truck, which was a factory cable linkage to start with, and the stock pedal in that truck works fine with the TPI. It even accepted a stock replacement C-4 vette throttle cable, same firewall gromet, cable end and Spacing between firewall and pedal arm. Hooked right up and works fine.
Based on That I was assuming that GM designed the cable linkage pedal geometry Once, and stuck with that geometry for years. Certainly the 73-87 trucks were designed long before the TPI was a gleam in anyone's eye.
BTW - I Did, after the initial assembly, modify the cable attachment point on the TB to make the throttle a bit less responsive, less likely to be "jostled" during rough off-roading with my Foot bouncing around. I moved the cable pickup further out away from the TB pivot. Even with That done I still get 100% TB rotation before I run out of pedal travel in the cab..
Reason I ask is that I have a TPI setup in a '78 pickup truck, which was a factory cable linkage to start with, and the stock pedal in that truck works fine with the TPI. It even accepted a stock replacement C-4 vette throttle cable, same firewall gromet, cable end and Spacing between firewall and pedal arm. Hooked right up and works fine.
Based on That I was assuming that GM designed the cable linkage pedal geometry Once, and stuck with that geometry for years. Certainly the 73-87 trucks were designed long before the TPI was a gleam in anyone's eye.
BTW - I Did, after the initial assembly, modify the cable attachment point on the TB to make the throttle a bit less responsive, less likely to be "jostled" during rough off-roading with my Foot bouncing around. I moved the cable pickup further out away from the TB pivot. Even with That done I still get 100% TB rotation before I run out of pedal travel in the cab..
Thread Starter
Le Mans Master
Joined: Aug 2000
Posts: 6,273
Likes: 14
From: Austin TX
Thanks, fellas.
The C4 diagram is instructive although it looks like I need one side by side with the C3 pedal and rod to compare the progressive nature of the curvature of each.
The TPI on my 71 uses the 71 accelerator pedal and bent/angled rod from pedal center to firewall to lever the throttle body cable. I'm trying to deal with the fact that this combo is only opening the throttle body about 40%. So I either have to modify the pedal assembly or the rotating pulley on the TB from the OE circular shape to an oval Nautilus shape.
Any advice?
The C4 diagram is instructive although it looks like I need one side by side with the C3 pedal and rod to compare the progressive nature of the curvature of each.
The TPI on my 71 uses the 71 accelerator pedal and bent/angled rod from pedal center to firewall to lever the throttle body cable. I'm trying to deal with the fact that this combo is only opening the throttle body about 40%. So I either have to modify the pedal assembly or the rotating pulley on the TB from the OE circular shape to an oval Nautilus shape.
Any advice?
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Drifting
Joined: Jun 2007
Posts: 1,478
Likes: 4
From: Formerly from the Great White North but now residing in the Desert Southwest NM (The Land of Dis-Enchantment?)
I have a '73 with FI. Originally used a TPI out of a '90 but now have a different system. When I used the TPI, I got a cable and the FI kit From Lokar and it worked great with the stock pedal linkage. Full travel and smooth operation.
