Last time I ran my car at the track the best mph was 99. That is with 3.89 gears. Would dropping down to say 3.08 gears give me any more mph? I realize the mph is a good indication of horsepower. So i guess if I add HP then the mph will come up as well. How much will a 10 hp increase affect my mph? Removing weight is like adding HP because your increasing the power to weight ratio. Am I on the right track? I just want to get more mph out of it. Thanks guys.
How to get more MPH in the 1/4
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A 454 that will only run 99 in the 1/4! Generally a steeper gear will help MPH, not the other way around--you want the car to accelerate quicker, not slower. Getting the weight down will make a big difference, as will decreasing drag and friction. Sometimes a small chin spoiler helps, block off the grill with plexiglass or sheetmetal (remove it for street use), pump up the tires to 45-50psi (at only 99 I'm guessing you don't have traction issues, so pump the rears up too) Lower the car, skinny tires, keep the windows rolled up (I see some hick tracks don't require rolled up windows like real tracks) align the front end as straight as possible, synthetic lube in the engine, trans, and rearend, remove the fan belt/s (push the car to the line to avoid overheating) the belt alone should get you to 100! I didn't think any 454 made less than 300 h.p.-an easy way would be to swap for a 350 small block!!
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508 Posts
I agree on 99.9 %of ^^^^^^^^^^^^.:yes: but if the motor is tacking out do too power curve and a short tire the 3.89 might be to much! not sure what your set up is but if the motor feels like it can go higher RPM'S then yes a steeper gear will help but if it feels like its at the end of its power on the top end then either a taller tire or a 3.42 gear set will help. as far as hp per mph, it takes about 15-20 HP to gain 1 MPH. and the general rule of thumb is every 7 lbs = 1 HP so in the weight reduction part you would have to shave at least 100 lbs to gain aprox. 1 MPH. but you can also try playing with the timing on the motor and jetting the carb. alot can come out just by tunning. my current combo went from 120 to 128 just by tuning.:yes:
Thanks for the responses guys. The guy I bought the engine from put a rv cam in it. Other than that it's a stock 85 model low compression 454. Engine is turning around 5500 rpm's through the traps. It still feels like it's pulling as well.
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What size tire do you run? What converter? A little 26" tire with a 3.89 gear would be turning only 5000 at 99, not accounting for slippage.
The tires I was running at the track the last time were some p225 60r 15. Running a B&M holeshot 3000 converter. I have upgraded in the tire dept. with some mickey thompson ET streets 275 60 15, also installed some sub frame connectors. Haven't been back to the track since.
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508 Posts
i think with the taller tire you wil increase the MPH. if you had any wheel spin before you might also clean that up with the tire having more roll out. good luck and keep us posted.
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36 Posts
Another option....
A low compression 454 with late model (1976 & newer)penut port heads do not make much HP at 5500RPM.
These heads do not flow at all.I think they peak at 4500 RPM.If you have these heads,replace them with older large oval port heads with a good dual plane intake manifold will make a big difference in power above 4000rpm.
A low compression 454 with late model (1976 & newer)penut port heads do not make much HP at 5500RPM.
These heads do not flow at all.I think they peak at 4500 RPM.If you have these heads,replace them with older large oval port heads with a good dual plane intake manifold will make a big difference in power above 4000rpm.
Yeah, I'm running a set of peanut port heads. I have been looking for some 781 or 049 large oval ports for it, haven't had much luck though. It's also a very low compression engine I'm guessing 7:1. Also running the factory cast iron quadrajet intake.
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4,612 Posts
adjust your
brakes just a tad loser , at least make sure they're not dragging.
Caterpillar makes some 50 gear oil i'm gonna use this time. I used it in the transmissions of my trucks ( tractor trailers, thought it might do better than synthetic and it did but gained some temp back after a month of heavy use ). I serviced Cat equipment on a surface mine , 50 weight is what goes in the final drive planetarys of D 11 dozers. So if it will stand that ,, it oughta be good for one pass in the 1/4 at a time i'd say.
what kind of air filter are you using ??
exhaust ?
i'd adjust the valves ( assuming its hyd ) where the lash is just out of them and get poly locks to keep them there.
put a ford solenoid on the positive cable coming from the battery , wire it up so you can disconnet the batteries load from the alternater just before you make the pass.
could get an underdrive pulley for the crank to spin the water pump slower while your at the track , could keep both pulleys with ya and both belts needed
get a distributor curve kit and see if bringing the timing in quicker , or slower , might help ur mph
really depends how bad you want that extra MPH
get some of this
http://www.jegs.com/i/Pro+Blend/797/6080/10002/-1
and mix with the wheel bearing grease for the front wheels.
put 2oz on this
http://www.jegs.com/i/Pro+Blend/797/6074/10002/-1
in ur rear gear oil
disconnect the vacume line going to ur trans modulator and plug the carb side ,, it should shift harder,, or u could install a shift kit in the transmission
brakes just a tad loser , at least make sure they're not dragging.
Caterpillar makes some 50 gear oil i'm gonna use this time. I used it in the transmissions of my trucks ( tractor trailers, thought it might do better than synthetic and it did but gained some temp back after a month of heavy use ). I serviced Cat equipment on a surface mine , 50 weight is what goes in the final drive planetarys of D 11 dozers. So if it will stand that ,, it oughta be good for one pass in the 1/4 at a time i'd say.
what kind of air filter are you using ??
exhaust ?
i'd adjust the valves ( assuming its hyd ) where the lash is just out of them and get poly locks to keep them there.
put a ford solenoid on the positive cable coming from the battery , wire it up so you can disconnet the batteries load from the alternater just before you make the pass.
could get an underdrive pulley for the crank to spin the water pump slower while your at the track , could keep both pulleys with ya and both belts needed
get a distributor curve kit and see if bringing the timing in quicker , or slower , might help ur mph
really depends how bad you want that extra MPH
get some of this
http://www.jegs.com/i/Pro+Blend/797/6080/10002/-1
and mix with the wheel bearing grease for the front wheels.
put 2oz on this
http://www.jegs.com/i/Pro+Blend/797/6074/10002/-1
in ur rear gear oil
disconnect the vacume line going to ur trans modulator and plug the carb side ,, it should shift harder,, or u could install a shift kit in the transmission
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1,848 Posts
If they are dragging, what is the solution to free them up?
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2,950 Posts
Have you done any changes to jetting in your carb. Are you running and electric and manual pump. What is your fuel pressure at the top end.
what kind of air filter are you using ?? I'm using a 4 inch tall by 14 inch dia pleated paper filter.
exhaust ? Longtube headers with a 2 1/2 "X" pipe Summit race flow welded muffs, 2 1/2 tail pipes out the rear.
i'd adjust the valves ( assuming its hyd ) where the lash is just out of them and get poly locks to keep them there.
put a ford solenoid on the positive cable coming from the battery , wire it up so you can disconnet the batteries load from the alternater just before you make the pass.
How do you do that?
could get an underdrive pulley for the crank to spin the water pump slower while your at the track , could keep both pulleys with ya and both belts needed
get a distributor curve kit and see if bringing the timing in quicker , or slower , might help ur mph
really depends how bad you want that extra MPH
get some of this
http://www.jegs.com/i/Pro+Blend/797/6080/10002/-1
and mix with the wheel bearing grease for the front wheels.
put 2oz on this
http://www.jegs.com/i/Pro+Blend/797/6074/10002/-1
in ur rear gear oil
disconnect the vacume line going to ur trans modulator and plug the carb side ,, it should shift harder,, or u could install a shift kit in the transmission[/QUOTE]
exhaust ? Longtube headers with a 2 1/2 "X" pipe Summit race flow welded muffs, 2 1/2 tail pipes out the rear.
i'd adjust the valves ( assuming its hyd ) where the lash is just out of them and get poly locks to keep them there.
put a ford solenoid on the positive cable coming from the battery , wire it up so you can disconnet the batteries load from the alternater just before you make the pass.
How do you do that?
could get an underdrive pulley for the crank to spin the water pump slower while your at the track , could keep both pulleys with ya and both belts needed
get a distributor curve kit and see if bringing the timing in quicker , or slower , might help ur mph
really depends how bad you want that extra MPH
get some of this
http://www.jegs.com/i/Pro+Blend/797/6080/10002/-1
and mix with the wheel bearing grease for the front wheels.
put 2oz on this
http://www.jegs.com/i/Pro+Blend/797/6074/10002/-1
in ur rear gear oil
disconnect the vacume line going to ur trans modulator and plug the carb side ,, it should shift harder,, or u could install a shift kit in the transmission[/QUOTE]
I have played around with the jetting on the carb. Also changed the shooters and accelerator pump cams. I really like the throttle response, instant and very snappy. I'm running a holley blue electric fuel pump. Fuel pressure is set to 7 psi. I don't have a gauge I can look at in the car so I don't know what the fuel pressure is at the top end of the track.
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9,228 Posts
A good converter can definitely increase top end MPH. We picked up 4 mph with the last change.
My torque converter is a crappy one from what I hear from people on here, it's a B&M Holeshot 3000. I don't need that big of one though, cam is just a RV towing cam. A stock converter will work fine with it. I just had the B&M already so I put it in. I also have a B&M Holeshot 2400 that I could try in it.
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