|
03-28-2024, 02:18 PM | #11 | |
Junior Member
Join Date: Jan 2024
Posts: 13
Likes: 1
Liked 49 Times in 7 Posts
|
Re: RPM dip doing onto stop, w/ racepak graphs
Quote:
i agree with above posts. i feel rpm is too low and shifting on time will clean some things up. would like to know if it is gas or alk ep |
|
03-28-2024, 06:01 PM | #12 | |
Junior Member
Join Date: Jun 2013
Posts: 12
Likes: 0
Liked 0 Times in 0 Posts
|
Re: RPM dip doing onto stop, w/ racepak graphs
Quote:
Electric shift Gas, C12 |
|
03-28-2024, 06:04 PM | #13 | |
Junior Member
Join Date: Jun 2013
Posts: 12
Likes: 0
Liked 0 Times in 0 Posts
|
Re: RPM dip doing onto stop, w/ racepak graphs
Quote:
Yes, on the crossover tube. |
|
03-28-2024, 06:10 PM | #14 | |
Junior Member
Join Date: Jun 2013
Posts: 12
Likes: 0
Liked 0 Times in 0 Posts
|
Re: RPM dip doing onto stop, w/ racepak graphs
Quote:
And shifting on time I'd probably be .5 minimum which is after the dip so it probably would make the car more consistent but I don't think it'd fix that problem. |
|
03-29-2024, 08:48 AM | #15 |
Junior Member
Join Date: Jan 2024
Posts: 13
Likes: 1
Liked 49 Times in 7 Posts
|
Re: RPM dip doing onto stop, w/ racepak graphs
if it were me i would try going on .20 shift at .70 pull rpm up to 4400. you can move the on and shift times if you like to get what you want in 60'. the shift time will typically be 2 to 1. meaning moving the shift .02 will move 60' .01. i would not get tangled up in my mph as long as it repeats and is predictable. trust me, i am not fast either but my car is relatively predictable so it doesn't matter that much to me. i will lose 3 mph in the 1/8 shifting on time vs. rpm.
make a few runs pulling the rpm up and shifting on time. see what the graph looks like and if it is consistent and exactly how much mph difference there is. if you dont like it you can always change it up. also you can move the shift time around to clean up dips and make it better. also if you stay with rpm i would still pull the rpm up on the stop. try that and see what it looks like. i wouldnt worry about creep as long as it repeats. i had a set up one time that creeped 1000 rpm when the stop came off but it was nasty. i agree with lenny about something on the vents to insure you are not sloshing fuel when it goes on the stop. i have a hose that runs from one vent to the other. there are 1000 ways to make a stop work. that is why you have to spend a lot of time testing and playing with things. ep |
Liked |
03-29-2024, 10:32 AM | #16 | |
Member
Join Date: Feb 2023
Location: Inver Grove Heights, MN
Posts: 108
Likes: 249
Liked 156 Times in 62 Posts
|
Re: RPM dip doing onto stop, w/ racepak graphs
Quote:
__________________
Tony Leonard S/C & S/ST 5160 |
|
04-03-2024, 02:14 PM | #18 |
Member
Join Date: Jan 2024
Location: Charlotte, NC
Posts: 171
Likes: 342
Liked 259 Times in 84 Posts
|
Re: RPM dip doing onto stop, w/ racepak graphs
I go on at .30, cruise at 4250-4300 with a CO2 stop and a really fat 30 year old carburetor. That set-up has been pretty good to me in 1/4 mile SST. 383 sbc at 2830lbs (6.30s W/O at that weight), usually 137 mph depending on weather and track.
I change mine to shift on RPM when I run 1/8th mile SST or any S/G, but I use the same .30 on and cruise speed, just add numbers on the back end. Just changing the shift to RPM usually gets me close to 6.90 given I have to go around 7.25 to the 1/8 to get me 10.90 in the 1/4 when shifting on time. It does dip a bit, but not enough to hear or affect much. I can see it on my Mega 400 RPM playback but the resolution is not very fine. Might be worse than I think it is but I think I'd rather just not know. Ignorance is bliss. Despite being slow, I'm more of a "get me close and figure it out before the finish line" kinda guy. Also never really had a T-stop ratio, I just try to get it close.
__________________
#2827 N/SA 1980 Malibu SW 2S 305/180 #2827 S/ST 1978 Mazda RX7 w/ 383 sbc/glide |
|
|