MonteCarloSS.com
MonteCarloSS.com

CELEBRATING 20 YEARS!

Previous Thread
Next Thread
Print Thread
#1073725 04/26/22 12:01 AM
Joined: Jun 2006
Posts: 1,914
15+ Year
Member
OP Offline
15+ Year
Member
Joined: Jun 2006
Posts: 1,914
The Detroit Region Season Opener was supposed to have happened yesterday, turns out someone missed something on the insurance form and we lost our site. Good thing the North West Ohio region around Toledo had a few spots still open for their Season Opener.

Honestly, I changed a lot on the car all at once, New engine, New transmission, New front suspension and shocks so this was a total crap shoot and I have to completely re-learn how to drive the car. came in 7 out 9 in CAM, But the big take away from this even is that I need a better seat. I was rolling around like a greased up bowling ball in the stock seats. Hard to drive well when you're holding on for dear life. Also the throttle is like an on/off switch, whoever said drive by wire throttle bodies aren't responsive, you have an open invitation to drive my car.

Here's the run
https://www.youtube.com/watch?v=JDA5hxcwE_Q&ab_channel=TravisJones


86 SS 6.2l LS3, Ilmor intake, Summit Stage 4 Cam, Stainless long tube headers, Stainless 3in exhaust, Tremec T-56 Magnum 6 speed, Eaton Truetrac 8.8 LSD, UMI Cornermax Front Suspension, 3-link Rear suspension w/ UMI Control Arms, UMI Front & Rear Braces, Brembo Brakes
Joined: Dec 2007
Posts: 6,736
Likes: 5
S
10+ Year
Member
Offline
10+ Year
Member
S
Joined: Dec 2007
Posts: 6,736
Likes: 5
They say you can tune that light switch action out of them, I've never felt that work in person though.

Engine sounds great though and the front sure looks way more responsive to inputs.


Lance
1985 Monte Carlo SS Street Car
Joined: Jun 2006
Posts: 1,914
15+ Year
Member
OP Offline
15+ Year
Member
Joined: Jun 2006
Posts: 1,914
Originally Posted by SSLance
They say you can tune that light switch action out of them, I've never felt that work in person though.

Engine sounds great though and the front sure looks way more responsive to inputs.


Yeah, I mean it also might be me not being stable in my seat adding to it. The beauty of having a friend with a Dyno and hundreds of hours tuning the software is that we can adjust it however we want. (providing we can get his four letter word car off the dyno and running right) The engine is as responsive as I could have hoped for, running in 2nd gear (2.10) with only a 3.15 rear I can blow the tires off (275/35R18 RE-71Rs) on command, and I bought a set of 3.73's when I put the motor together thinking it would be a little doggy below 3000rpm. I'm going to try get the car on some scales, I have a feeling that the front was too low and taking weight off the rear. I think its all setup from here.

An experienced auto crosser who watched the run said that the car didn't roll or pitch fore/aft. So I suppose the CornerMax front works.


86 SS 6.2l LS3, Ilmor intake, Summit Stage 4 Cam, Stainless long tube headers, Stainless 3in exhaust, Tremec T-56 Magnum 6 speed, Eaton Truetrac 8.8 LSD, UMI Cornermax Front Suspension, 3-link Rear suspension w/ UMI Control Arms, UMI Front & Rear Braces, Brembo Brakes
Joined: May 2002
Posts: 4,550
M
MAP Offline
20+ Year
Member
Offline
20+ Year
Member
M
Joined: May 2002
Posts: 4,550
There are mechanical methods to deal with a touchy throttle that won't be overcome by DBW. The way to do this is to adjust the relationship between linear pedal travel and angular opening of the throttle. If we divide the first by the second, we want the early opening ratio to be fractionally high, and the late opening fractionally low. There are two degrees of freedom here: the opening lever length and the angular relationship between the lever and the actuation cable. These have to be played against the linear travel limits of the gas pedal.

Last edited by MAP; 04/28/22 01:36 AM.
Joined: Dec 2007
Posts: 6,736
Likes: 5
S
10+ Year
Member
Offline
10+ Year
Member
S
Joined: Dec 2007
Posts: 6,736
Likes: 5
I have a double throttle return spring setup on my throttle body. When Bernie first got in my car he said " Can we do something about this super stiff throttle pedal?" He was afraid that he wouldn't be able to put power down smoothly having to push so hard. He never mentioned it again though once he got on course. He actually had to adjust more to my light pressure brake pedal than my heavy pressure throttle pedal.

I've always thought that it's easier to control how I put power down with a heavy throttle pedal.

I know with Holley EFI there is a way to adjust the reaction % of the DBW pedal travel, not sure if you can do the same with OEM ECU. Basically you trim it so in early travel the pedal has to move a lot further to get the same movement of the throttle blade opening. It doesn't make the pedal harder to push but does slow down the movement of the throttle blade.


Lance
1985 Monte Carlo SS Street Car
Joined: Apr 2011
Posts: 1,270
10+ Year
Member
Online Content
10+ Year
Member
Joined: Apr 2011
Posts: 1,270
I'll have to take a look at HP Tuners again, but I'm pretty sure that is a fairly easy to access, but sometimes a little touchy on changes and easy to go out of whack. There's some functional tables out there that can give more responsiveness so I would think you could compare that to the stock table and move the opposite direction by a similar amount and be ok. I think the general consensus is that a little change goes a long way, but it's doable generally.

On the mechanical stuff, I've always preferred a stiff gas pedal too, even on DD's (and especially stick shifts). Much easier to control for me if I'm having to lean on it a little bit vs accidentally resting my foot near the pedal and raising the RPM by 1500...


Shawn

'85 MC with budget 5.3L swap, TH350 with stock 2.14 rear end
It ain't much off the line, but it's nice on the highway
Joined: Jun 2006
Posts: 1,914
15+ Year
Member
OP Offline
15+ Year
Member
Joined: Jun 2006
Posts: 1,914
Originally Posted by MAP
There are mechanical methods to deal with a touchy throttle that won't be overcome by DBW. The way to do this is to adjust the relationship between linear pedal travel and angular opening of the throttle. If we divide the first by the second, we want the early opening ratio to be fractionally high, and the late opening fractionally low. There are two degrees of freedom here: the opening lever length and the angular relationship between the lever and the actuation cable. These have to be played against the linear travel limits of the gas pedal.


Part of it is that I just have a really responsive motor (high compression, tiny damper, lightweight rods and pistons, light flywheel and clutch), but if we put it on the dyno and do some steady state work we can control tip in, response, and signal filtering to get it "better" than factory.

Originally Posted by SSLance
I know with Holley EFI there is a way to adjust the reaction % of the DBW pedal travel, not sure if you can do the same with OEM ECU. Basically you trim it so in early travel the pedal has to move a lot further to get the same movement of the throttle blade opening. It doesn't make the pedal harder to push but does slow down the movement of the throttle blade.


Lance I'm running a boat ECU, we have the developer level software to make any changes we want, it is virtually endlessly configurable, I could run 2 throttle bodies, boost control, PWM fuel pump, add inputs for a dozen sensors, its like a Holley Dominator on steroids. It's a real shame that the company that makes doesnt sell it in the aftermarket because it makes everything save for a Bosch Motorsports ECU or a High End Motec look like a GM TBI ECU, when comparing raw computing horsepower.


86 SS 6.2l LS3, Ilmor intake, Summit Stage 4 Cam, Stainless long tube headers, Stainless 3in exhaust, Tremec T-56 Magnum 6 speed, Eaton Truetrac 8.8 LSD, UMI Cornermax Front Suspension, 3-link Rear suspension w/ UMI Control Arms, UMI Front & Rear Braces, Brembo Brakes
Joined: Jul 2003
Posts: 9,280
S
15+ Year
Member
Offline
15+ Year
Member
S
Joined: Jul 2003
Posts: 9,280
I bet that car will carry a lot more speed through the turns. Were you feeling the limits of the tires?

I was planning on calculating the cross-sectional area that is revealed by the throttle as a function of angle and mapping the throttle pedal to that linearly.


Link Copied to Clipboard
Help MonteCarloSS.com


Recent Contributors
86BlackSuperSport
Authorized Vendors
Tell them you saw it
on MonteCarloSS.com!


Dixie Monte Carlo Depot
Mikes Montes
Powered by UBB.threads™ PHP Forum Software 7.7.5