slow acceleration

Go down

slow acceleration

Post  cool40 on September 14th 2014, 7:09 pm

i looked at the msd grid today and notice the same slow acceleration rate on the graph.the first second after launch it just dont gain rpm like i want it to.is this normal or as some say "riding the converter"? i have had 4 tq converters behind it that range from 4500-6800 and it has always acted the same way. any ideas? 1.12 60' on that pass...... study
avatar
cool40
BBF CONTRIBUTOR
BBF CONTRIBUTOR

Posts : 7165
Join date : 2009-08-31
Age : 47
Location : on the 1/8 mile dyno

View user profile

Back to top Go down

Re: slow acceleration

Post  dfree383 on September 14th 2014, 8:17 pm

Between waves. Header work might help or keep the engine above that.
avatar
dfree383
BBF CONTRIBUTOR
BBF CONTRIBUTOR

Posts : 14151
Join date : 2009-07-09
Location : Home Wif Da Wife.....

View user profile

Back to top Go down

Re: slow acceleration

Post  cool40 on September 14th 2014, 9:09 pm

dfree383 wrote:Between waves. Header work might help or keep the engine above that.
sure a possibility. Short side exit 2.5" tube.
avatar
cool40
BBF CONTRIBUTOR
BBF CONTRIBUTOR

Posts : 7165
Join date : 2009-08-31
Age : 47
Location : on the 1/8 mile dyno

View user profile

Back to top Go down

Re: slow acceleration

Post  richter69 on September 14th 2014, 9:30 pm

after the "flash" the converter is gonna grab ahold and tug it down some, looks like it was stuck pretty good also
avatar
richter69

Posts : 13645
Join date : 2008-12-02
Age : 47
Location : In the winners circle

View user profile

Back to top Go down

Re: slow acceleration

Post  cool40 on September 14th 2014, 11:04 pm

richter69 wrote:after the "flash" the converter is gonna grab ahold and tug it down some, looks like it was stuck pretty good also
thats the funny thing,it hasn't changed how it accelerates that first second.i thought the gear change would help it get up quicker which it did help low gear but still has this flat line.i wonder if it could be in the fuel Question i thought it was in the timing map in the grid but its not an issue,its set on 34*all the time.
avatar
cool40
BBF CONTRIBUTOR
BBF CONTRIBUTOR

Posts : 7165
Join date : 2009-08-31
Age : 47
Location : on the 1/8 mile dyno

View user profile

Back to top Go down

Re: slow acceleration

Post  dfree383 on September 15th 2014, 2:40 am

cool40 wrote:
dfree383 wrote:Between waves. Header work might help or keep the engine above that.
sure a possibility. Short side exit 2.5" tube.

To big of tubes and work on the length and collector
avatar
dfree383
BBF CONTRIBUTOR
BBF CONTRIBUTOR

Posts : 14151
Join date : 2009-07-09
Location : Home Wif Da Wife.....

View user profile

Back to top Go down

Re: slow acceleration

Post  cool40 on September 15th 2014, 9:50 am

dfree383 wrote:
cool40 wrote:
dfree383 wrote:Between waves. Header work might help or keep the engine above that.
sure a possibility. Short side exit 2.5" tube.

To big of tubes and work on the length and collector
I should have made them 2 3/8 but not sure about how they can be longer. I like everything about side exit but the sound!
avatar
cool40
BBF CONTRIBUTOR
BBF CONTRIBUTOR

Posts : 7165
Join date : 2009-08-31
Age : 47
Location : on the 1/8 mile dyno

View user profile

Back to top Go down

Re: slow acceleration

Post  dfree383 on September 15th 2014, 10:17 am

cool40 wrote:
dfree383 wrote:
cool40 wrote:
dfree383 wrote:Between waves. Header work might help or keep the engine above that.
sure a possibility. Short side exit 2.5" tube.

To big of tubes and work on the length and collector
I should have made them 2 3/8 but not sure about how they can be longer. I like everything about side exit but the sound!

2 3/8 is probably too big..... A 2 1/8 step to 2 1/4 would probably be closer.
avatar
dfree383
BBF CONTRIBUTOR
BBF CONTRIBUTOR

Posts : 14151
Join date : 2009-07-09
Location : Home Wif Da Wife.....

View user profile

Back to top Go down

Re: slow acceleration

Post  maverick on September 15th 2014, 10:57 am

cool40 wrote:
dfree383 wrote:
cool40 wrote:
dfree383 wrote:Between waves. Header work might help or keep the engine above that.
sure a possibility. Short side exit 2.5" tube.

To big of tubes and work on the length and collector
I should have made them 2 3/8 but not sure about how they can be longer. I like everything about side exit but the sound!


They sound ok from inside the car....screw everybody else. Razz
avatar
maverick
BBF CONTRIBUTOR
BBF CONTRIBUTOR

Posts : 3052
Join date : 2009-08-06
Age : 66

View user profile

Back to top Go down

Re: slow acceleration

Post  FalconEh on September 15th 2014, 11:20 am

richter69 wrote:after the "flash" the converter is gonna grab ahold and tug it down some, looks like it was stuck pretty good also

 photo data_zps62bdec4f.jpg


X2 that's what I see too... normal, after the initial slingshot the weight of the car is going to essentially be heavier once that initial hook has completed looking ad your graph it is only in 1st not 2nd.
avatar
FalconEh

Posts : 1426
Join date : 2014-08-21
Location : on the blacktop or in the mountains ????

View user profile

Back to top Go down

Re: slow acceleration

Post  richter69 on September 15th 2014, 8:29 pm

My side exits spound good.......

https://youtu.be/3Q_NMGlGUX8
avatar
richter69

Posts : 13645
Join date : 2008-12-02
Age : 47
Location : In the winners circle

View user profile

Back to top Go down

Re: slow acceleration

Post  cool40 on September 15th 2014, 8:48 pm

i just dont like the sound at idle,anything else is good.my #1 is the fact i dont have a car full of alky fumes! i may build another set with smaller tubes but they'll be tested before i drop $$ for coating! i need to look again but i'm thinking the ex port is 2 1/4". Suspect
avatar
cool40
BBF CONTRIBUTOR
BBF CONTRIBUTOR

Posts : 7165
Join date : 2009-08-31
Age : 47
Location : on the 1/8 mile dyno

View user profile

Back to top Go down

Re: slow acceleration

Post  Larry T on September 15th 2014, 9:12 pm

cool40 wrote:i looked at the msd grid today and notice the same slow acceleration rate on the graph.the first second after launch it just dont gain rpm like i want it to.is this normal or as some say "riding the converter"? i have had 4 tq converters behind it that range from 4500-6800 and it has always acted the same way. any ideas? 1.12 60' on that pass...... study


look to see if you have a delay something like 1.500 sec? i had a delay in mine the graph looked similar it was to help get passed the slick 60ft with the candles lit Smile  maybe it wants moor or less fuel in that rpm range? it looks to be balls out after the shift.
avatar
Larry T

Posts : 1076
Join date : 2009-01-08
Location : leicester,NC

View user profile

Back to top Go down

Re: slow acceleration

Post  FalconEh on September 15th 2014, 10:35 pm

richter69 wrote:My side exits spound good.......

https://youtu.be/3Q_NMGlGUX8

Yup, it does, nice pedal job...did I hear limiter in the BOB ???
avatar
FalconEh

Posts : 1426
Join date : 2014-08-21
Location : on the blacktop or in the mountains ????

View user profile

Back to top Go down

Re: slow acceleration

Post  richter69 on September 15th 2014, 10:45 pm

burnout limiter, I get carried away sometimes.....


the bitch was on a run, my guy had me to far to the left of the groove, cars been pullin left some as Im still twisting on the ladderbar adjusters and it drove outta the sticky..... Im used to it here lately.
avatar
richter69

Posts : 13645
Join date : 2008-12-02
Age : 47
Location : In the winners circle

View user profile

Back to top Go down

Re: slow acceleration

Post  richter69 on September 15th 2014, 10:53 pm

idk Lee, I assume you have a highspeed on it? I Maybe pour the fuel to it down low? been awhile since I messed w mfi and M5 lol.
avatar
richter69

Posts : 13645
Join date : 2008-12-02
Age : 47
Location : In the winners circle

View user profile

Back to top Go down

Re: slow acceleration

Post  cool40 on September 15th 2014, 11:23 pm

richter69 wrote:idk Lee, I assume you have a highspeed on it? I Maybe pour the fuel to it down low? been awhile since I messed w mfi and M5 lol.
i turned the high speed over so it dont work but hope to try it soon. im gona lean it out some and see what it does.
avatar
cool40
BBF CONTRIBUTOR
BBF CONTRIBUTOR

Posts : 7165
Join date : 2009-08-31
Age : 47
Location : on the 1/8 mile dyno

View user profile

Back to top Go down

Re: slow acceleration

Post  FalconEh on September 15th 2014, 11:52 pm

cool40 wrote:
richter69 wrote:idk Lee, I assume you have a highspeed on it? I Maybe pour the fuel to it down low? been awhile since I messed w mfi and M5 lol.
i turned the high speed over so it dont work but hope to try it soon. im gona lean it out some and see what it does.

Looks like it hooks in an oil bath! What is the beginning of your torque curve on relation to the track +- Probably not on the right track, but sometimes if you soften the hook you wait less for the weight transfer...Profile picture is perfect. I would be leary of leaning out such an awesome piece that I believe is not HP related.JMO (PS Iam not worthy)

Richter69 no offence intended, called it the way I heard it with a hint of friendly sarcasm. Embarassed
avatar
FalconEh

Posts : 1426
Join date : 2014-08-21
Location : on the blacktop or in the mountains ????

View user profile

Back to top Go down

Re: slow acceleration

Post  FalconEh on September 15th 2014, 11:57 pm

or...maybe a few degrees more timing for the launch?
avatar
FalconEh

Posts : 1426
Join date : 2014-08-21
Location : on the blacktop or in the mountains ????

View user profile

Back to top Go down

Re: slow acceleration

Post  richter69 on September 16th 2014, 12:13 am

If you talking about mine, that pic bent a lot of stuff. 

Sorry to whore your thread up Lee. 

Id get the highspeed working, make it fat down low and lean it out on top...)
avatar
richter69

Posts : 13645
Join date : 2008-12-02
Age : 47
Location : In the winners circle

View user profile

Back to top Go down

Re: slow acceleration

Post  cool40 on September 16th 2014, 12:16 am

FalconEh wrote:
cool40 wrote:
richter69 wrote:idk Lee, I assume you have a highspeed on it? I Maybe pour the fuel to it down low? been awhile since I messed w mfi and M5 lol.
i turned the high speed over so it dont work but hope to try it soon. im gona lean it out some and see what it does.

Looks like it hooks in an oil bath! What is the beginning of your torque curve on relation to the track +- Probably not on the right track, but sometimes if you soften the hook you wait less for the weight transfer...Profile picture is perfect. I would be leary of leaning out such an awesome piece that I believe is not HP related.JMO (PS Iam not worthy)

Richter69 no offence intended, called it the way I heard it with a hint of friendly sarcasm. Embarassed
the car IMO needs some wheel speed.i think i can get it dialed in with the wheelie bars but so far its been very hard to get down the track.it was going left before i changed the 4.30 gear to 4.86 then went right.i backed the preload down and got it leaving better but its inconsistent. ive ran the fuel "safe" all this time working on the chassis but its time to get with the program! i'm very happy it hit the 4.99 mark but i know it'll do better,,,4.80's  pig  funny thing about that profile pic...i was leaving on the converter @6600. i was still learning the msd grid and didnt have the low side rev working. i want to tune on the motor but more power brings more problems at this point.lol
avatar
cool40
BBF CONTRIBUTOR
BBF CONTRIBUTOR

Posts : 7165
Join date : 2009-08-31
Age : 47
Location : on the 1/8 mile dyno

View user profile

Back to top Go down

Re: slow acceleration

Post  cool40 on September 16th 2014, 12:22 am

FalconEh wrote:or...maybe a few degrees more timing for the launch?
i plan to try this as its easy to do with the grid.

richter69 wrote:If you talking about mine, that pic bent a lot of stuff. 

Sorry to whore your thread up Lee. 

Id get the highspeed working, make it fat down low and lean it out on top...)
i do think the highspeed would be a plus with my setup.the A-1 pump moves 50%more fuel than i need but the A1/2 was about too small.my pump also runs off the dry sump pump so its turning a little faster than it was so its fat,lol
avatar
cool40
BBF CONTRIBUTOR
BBF CONTRIBUTOR

Posts : 7165
Join date : 2009-08-31
Age : 47
Location : on the 1/8 mile dyno

View user profile

Back to top Go down

Re: slow acceleration

Post  FalconEh on September 16th 2014, 12:29 am

cool40 wrote:
FalconEh wrote:
cool40 wrote:
richter69 wrote:idk Lee, I assume you have a highspeed on it? I Maybe pour the fuel to it down low? been awhile since I messed w mfi and M5 lol.
i turned the high speed over so it dont work but hope to try it soon. im gona lean it out some and see what it does.

Looks like it hooks in an oil bath! What is the beginning of your torque curve on relation to the track +- Probably not on the right track, but sometimes if you soften the hook you wait less for the weight transfer...Profile picture is perfect. I would be leary of leaning out such an awesome piece that I believe is not HP related.JMO (PS Iam not worthy)

Richter69 no offence intended, called it the way I heard it with a hint of friendly sarcasm. Embarassed
the car IMO needs some wheel speed.i think i can get it dialed in with the wheelie bars but so far its been very hard to get down the track.it was going left before i changed the 4.30 gear to 4.86 then went right.i backed the preload down and got it leaving better but its inconsistent. ive ran the fuel "safe" all this time working on the chassis but its time to get with the program! i'm very happy it hit the 4.99 mark but i know it'll do better,,,4.80's  pig  funny thing about that profile pic...i was leaving on the converter @6600. i was still learning the msd grid and didnt have the low side rev working. i want to tune on the motor but more power brings more problems at this point.lol

Maybe I am th ewhore that Richter69 is talking about, but were bench racing and conversation breeds thoughts, So at the risk of further whoring the thread... 4.56 JK  I believe the chassis first straight and consistant, and the profile pic although I called it perfect is loading the right rear with that much HP TQ, do you run the same setup side to side on the rear suspension ? have you tried to add in some on the diagional (LF/RR) for the motor? The 4.99 is Awesome Congrats, Probably less than the 6600 in the pick would be optimum.
avatar
FalconEh

Posts : 1426
Join date : 2014-08-21
Location : on the blacktop or in the mountains ????

View user profile

Back to top Go down

Re: slow acceleration

Post  FalconEh on September 16th 2014, 12:36 am

richter69 wrote:If you talking about mine, that pic bent a lot of stuff. 

Sorry to whore your thread up Lee. 

Id get the highspeed working, make it fat down low and lean it out on top...)

No

My Bad
avatar
FalconEh

Posts : 1426
Join date : 2014-08-21
Location : on the blacktop or in the mountains ????

View user profile

Back to top Go down

Re: slow acceleration

Post  cool40 on September 16th 2014, 1:08 am

when i first got the chassis done we set it up on scales. i didnt like how things were adjusted to get rear wheel weight so i changed it before i ever ran it.i put less than 1/2 turn in the top right bar to get it going down the track. i guess the flat line i see may be normal i just look for all i can get in 60'.
avatar
cool40
BBF CONTRIBUTOR
BBF CONTRIBUTOR

Posts : 7165
Join date : 2009-08-31
Age : 47
Location : on the 1/8 mile dyno

View user profile

Back to top Go down

Back to top


 
Permissions in this forum:
You cannot reply to topics in this forum