power lacking on low end
+9
Mark Miller
cool40
Curt
rmcomprandy
bbf-falcon
4604X4
69F100
Gary Varney
frank13
13 posters
Page 1 of 2
Page 1 of 2 • 1, 2
power lacking on low end
Ok been to the track a few times now....
First issue was the car would NOT get past 4900 rpm no matter what.....Come to find the springs were installed wrong....way too little pressure....a few shims later and vialo- 6500 with ease and looking for more.... problem fixed
Now we have a new problem/issue Car is lacking low end power.....takes FOREVER to get to the 4000 rpm. once it hits that, the car pulls with authority.
Been advised to pull the cover and check the timing set to make sure its a pre 71 and not the retarded 72 and above. This seems reasonable to me as the valves may be opening late.
Cam is installed "dot to dot"
cam is a lunati 61605
motor is a 10.75 to one
466
stock crank, forged rods and pistons
Pi heads,
stealth intake
7850 holley carb with perc adjustajets
trnas is t56 cobra clutch
First issue was the car would NOT get past 4900 rpm no matter what.....Come to find the springs were installed wrong....way too little pressure....a few shims later and vialo- 6500 with ease and looking for more.... problem fixed
Now we have a new problem/issue Car is lacking low end power.....takes FOREVER to get to the 4000 rpm. once it hits that, the car pulls with authority.
Been advised to pull the cover and check the timing set to make sure its a pre 71 and not the retarded 72 and above. This seems reasonable to me as the valves may be opening late.
Cam is installed "dot to dot"
cam is a lunati 61605
motor is a 10.75 to one
466
stock crank, forged rods and pistons
Pi heads,
stealth intake
7850 holley carb with perc adjustajets
trnas is t56 cobra clutch
Re: power lacking on low end
I know the feeling, I could write a book on everything my stuff has thrown at me this year. Developed a miss and changed EVERYTHING but the paint color and still had it. Many track rentals and 43 runs later I found a plate in the hood scoop had evidently moved causing the air to pull fuel out through 1 of the high speed air bleeds at high speeds. That was just one of the many issues this season. Fought chasis issues, starter issues, fuel supply issues, transmission issues which I have always had good luck with. The latest is a cracked, yes cracked torque converter case that nearly got me in trouble at 160 mph. Good luck finding your problem!
Gary Varney- Posts : 102
Join date : 2009-09-07
Location : Etna, Ohio
Re: power lacking on low end
Frank I will send you pics of the intake tomorrow I keep forgetting to take some for you. Frank put you a automatic in it with a good stall so you leave at 4000.Have you tried leaving at 4000 or will your chassis hold dumping the clutch at 4000 rpms if so try it let it all hang out and hope it all stays together.
69F100- BBF CONTRIBUTOR
- Posts : 5386
Join date : 2009-01-04
Age : 58
Location : Irwinville Ga.
Re: power lacking on low end
Is your timing locked or advancing? If advancing, check the advance curve - make sure its working.
4604X4- Posts : 108
Join date : 2012-06-24
Re: power lacking on low end
so heres my issue....i thought the 460 was supposed to have balls down low.....i am looking for the torque this thing is supposed to have
Re: power lacking on low end
Gary Varney wrote:I know the feeling, I could write a book on everything my stuff has thrown at me this year. Developed a miss and changed EVERYTHING but the paint color and still had it. Many track rentals and 43 runs later I found a plate in the hood scoop had evidently moved causing the air to pull fuel out through 1 of the high speed air bleeds at high speeds. That was just one of the many issues this season. Fought chasis issues, starter issues, fuel supply issues, transmission issues which I have always had good luck with. The latest is a cracked, yes cracked torque converter case that nearly got me in trouble at 160 mph. Good luck finding your problem!
Sorry to hear this Gary.Sounds like its finally getting around to you. Sounds like some of my issues for the last couple of years w/Falcon.Hell,i've seen you change Tranny's in between rounds at a National event and still win the race. keep at it brother,hope to see you at Norwalk in Oct.
bbf-falcon- Posts : 8995
Join date : 2008-12-03
Location : Jackson, Ohio
Re: power lacking on low end
I don't mean to be unsympathetic on this because I do feel bad for your problems.
However, almost every engine I have built within the last ten years has been tuned or at least run on a dyno.
Before then any performance drawback was most always assumed to be an engine problem by the car owner but, now I have proof that it isn't.
However, almost every engine I have built within the last ten years has been tuned or at least run on a dyno.
Before then any performance drawback was most always assumed to be an engine problem by the car owner but, now I have proof that it isn't.
Re: power lacking on low end
here is a video from yb race last weekend.....
I left at 2500rpm drag radials..springs are way too stiff (road race suspension still on car)
after the 2 shift it picks up like a bat out of hell!
car went 113 at 12.73 reaction time was a whooping 1.143LOL sixty was 2.0 1/8 was 8.49 at 88
I left at 2500rpm drag radials..springs are way too stiff (road race suspension still on car)
after the 2 shift it picks up like a bat out of hell!
car went 113 at 12.73 reaction time was a whooping 1.143LOL sixty was 2.0 1/8 was 8.49 at 88
Re: power lacking on low end
What is the converter flashing at.
Curt- Posts : 2791
Join date : 2009-02-08
Age : 62
Location : Henrietta, Texas but mostly on the road
Re: power lacking on low end
its a t56.....Curt wrote:What is the converter flashing at.
cool40- BBF CONTRIBUTOR
- Posts : 7313
Join date : 2009-08-31
Age : 53
Location : on the 1/8 mile dyno
Re: power lacking on low end
cool40 wrote:its a t56.....Curt wrote:What is the converter flashing at.
LOL No wonder it's a dog off the line.
I was thinking it was a C4
Curt- Posts : 2791
Join date : 2009-02-08
Age : 62
Location : Henrietta, Texas but mostly on the road
Re: power lacking on low end
Was it spinning at 2,500 rpm if not keep raising the rpm launch till it spins.IMO,2,500 rpm is nowhere near high enough i wouldn't be suprised if it's not bogging.If it's bogging the rpm's are to low to recover.It's a stick shift so you're going to have to drive it like you hate it for it to et good IMO.It's not a automatic with a stall converter to flash into the higher rpm range that you need.
Later Mark
Later Mark
Mark Miller- Posts : 1959
Join date : 2009-09-01
Re: power lacking on low end
If it doesn't 60 ft it's not going to et good a 2.00 second 60 ft is not good.My 2011 F-150 Supercab 4X4 with EcoBoost V-6 had a 2.07 60 ft.
Later Mark.
Later Mark.
Mark Miller- Posts : 1959
Join date : 2009-09-01
Re: power lacking on low end
frank13 wrote:so heres my issue....i thought the 460 was supposed to have balls down low.....i am looking for the torque this thing is supposed to have
Did you degree the cam?
DO you know How to tune an engine?
DO you know how to set-up a drag car?
DO you have enough gear in the car?
DO you know how to drive a manual transmission in a drag car?
dfree383- BBF CONTRIBUTOR
- Posts : 14851
Join date : 2009-07-09
Location : Home Wif Da Wife.....
Re: power lacking on low end
Frank you need to leave at higher rpm was you sleeping on the tree you see that last yellow light come on dump the clucth and go .Put some heat in them tires gettem sticky it look likr when you got up in the r's it came alive.I agree try adding another 500 rpms each time until you start spinning the tires
69F100- BBF CONTRIBUTOR
- Posts : 5386
Join date : 2009-01-04
Age : 58
Location : Irwinville Ga.
Re: power lacking on low end
the t56 is gona take a dump but you will need to hit it harder to 60'.
cool40- BBF CONTRIBUTOR
- Posts : 7313
Join date : 2009-08-31
Age : 53
Location : on the 1/8 mile dyno
Re: power lacking on low end
frank13 wrote:t56 is going away....trying to work a deal on a c4 or powerglide trade.
If your going to drive it on the street use a C6
dfree383- BBF CONTRIBUTOR
- Posts : 14851
Join date : 2009-07-09
Location : Home Wif Da Wife.....
Re: power lacking on low end
dfree383 wrote:frank13 wrote:t56 is going away....trying to work a deal on a c4 or powerglide trade.
If your going to drive it on the street use a C6
why?
Re: power lacking on low end
Heavy duty, 3 gears and it will take a serious amount of abuse and not cost an arm and a leg.
dfree383- BBF CONTRIBUTOR
- Posts : 14851
Join date : 2009-07-09
Location : Home Wif Da Wife.....
Re: power lacking on low end
I agree,and you'll see your ET pickup also and more consistency.
bbf-falcon- Posts : 8995
Join date : 2008-12-03
Location : Jackson, Ohio
Re: power lacking on low end
timing cover off.....cloyes 3130 timing set....post 72 set 8 degrees retarded.....
new timing set being picked up in the am
new timing set being picked up in the am
Re: power lacking on low end
frank13 wrote:timing cover off.....cloyes 3130 timing set....post 72 set 8 degrees retarded.....
new timing set being picked up in the am
cool40- BBF CONTRIBUTOR
- Posts : 7313
Join date : 2009-08-31
Age : 53
Location : on the 1/8 mile dyno
Re: power lacking on low end
The post 72 timing set strikes again....................
IDT-572- BBF CONTRIBUTOR
- Posts : 4628
Join date : 2008-12-02
Age : 63
Location : Shelbyville Tn.
Re: power lacking on low end
Some one needs to Learn to degree a cam......... [u]
Last edited by dfree383 on September 10th 2012, 12:02 am; edited 1 time in total
dfree383- BBF CONTRIBUTOR
- Posts : 14851
Join date : 2009-07-09
Location : Home Wif Da Wife.....
Page 1 of 2 • 1, 2
Page 1 of 2
Permissions in this forum:
You cannot reply to topics in this forum