ET and speed headsratcher

[elevensies]

ok guys, my head is fuzzed with this, hope you can help

my car runs consistent 11.7 @ 113mph
it mostly always has 1.60 60'

but reading the "post your 11 second car figures" im reading alot of you guys who are around my 11.7 times have much higher speeds, why?

iv sad to my self a while now i feel like im not feeling anything in that last 1/3, like its flat
i wondered if a bigger carb would help, currently have a BG 750 Demon
im on 3.91 gears and 30" slicks

cheers guys

 

[dvw]

1.60, 11.7@113 shows the car is working pretty good for its power and weight. That's not much gear with a 30" tire. Unless you combo is extremely mild , gear would probably help. Borrow a pair of 28" tires and test. What rpm does it turn in the traps ?
Doug

 

[Frank Mopar]

Time would be the same but differences are:

You can either gear low, get away fast and drop off on the big end.

Or

Gear high, get away slower and pick up on the big end

Of course the torque converter has a big effect on it also.

 

[66Satellite47]

Of course a litter more gear will get you better results. A really good torque converter makes great results. 11.7 is good ET, but MPH should be more like 118 or so. IMHO

 

[Mike Gaines]

Some times we just figure that our car will just not run any faster....yours may just be a 113 mph car..

 

[33 IMP]

I would do a little research on Wallace calculator site. Do you have weight of your car, or dyno hp? Your 60 ft is better than mine, that means I need more power than you for the same e.t. and therefore I would probably mph better.
You might find that guys that e,t, the same as you, just don't have as good a chassis set-up, and need more motor.

 

[451Mopar]

My car has good MPH, around 120 MPH, but around 11.7 ET. 60' are not good, 1.8? Not set up for the track other than M/T Radial S/S tires. Still running mostly stock suspension with old KYB gas shocks, 0.990" T-Bars, front and rear sway bars. (at 4,150 lbs and at 6,000 ft altitude.)

 

[elevensies]

some really interesting points there guys thank you.

im going to try a smaller tyre 28 or 29, and increase the rear to 4.10 (possibly)
my converter is a 3800 pct unit, but its a few years old,
dyno is just over 500hp
full weight car and full interior inc a cage, so not 100% sure on weight, but its stock appearing
i still think a bigger carb could help the top end?
gearing and tyre is for sure my starting point

 

[elevensies]

1.60, 11.7@113 shows the car is working pretty good for its power and weight. That's not much gear with a 30" tire. Unless you combo is extremely mild , gear would probably help. Borrow a pair of 28" tires and test. What rpm does it turn in the traps ?
Doug

engine is making over 500, solid lifters roller rockers, usuual stuff,
now theres a good point, it traps at 5200 or thereabouts, which is what i shift at , this could be my mistake, i could shift later at say 5800, which may bring in more top end??? good point thanks

 

[66Satellite47]

I ran most of my motors to a 7000 RPM shift point. I used up several crankshafts. That's not good with stock 440 crankshafts. If you shift at 6200 RPM you may get better results. A little more gear would help.

 

[dvw]

11.7 is good ET, but MPH should be more like 118 or so. IMHO[/QUOTE]

My car has good MPH, around 120 MPH, but around 11.7 ET. 60' are not good, 1.8?[/QUOTE]

 

[dvw]

Both of these cars are way off the mark. At 118 should be around 11.2X. At 120 it should be around 11.0X. I'd also say that unless the original posters car is very heavy it doesn't show 500 hp. More like 450 hp if it's at an estimated 3800 lbs. That doesn't necessarily that the motor is off. Could an inefficient converter, lack of gear, or lack of power.
Doug

 

[elevensies]

Both of these cars are way off the mark. At 118 should be around 11.2X. At 120 it should be around 11.0X. I'd also say that unless the original posters car is very heavy it doesn't show 500 hp. More like 450 hp if it's at an estimated 3800 lbs. That doesn't necessarily that the motor is off. Could an inefficient converter, lack of gear, or lack of power.
Doug

the car makes over 500, thats dyno correct, but as i have already said its a complete car, so full weight plus a 6 point cage.
again, possibility the converter?? how do i tell?

 

[elevensies]

just been on wallace calculator, and iv put in all the variables, tyre height, rear ratios and the one thing that makes the biggest difference on MPH is shift time, so im going to increase my shift light, thats a start.
29" tyres help trap speed and keep 60 foot
my head hurts lol

 

[Frustration]

It looks like your car is pretty well sorted out. If your ET is high, and MPH is low, that is an efficient combination. MPH is a way to measure HP. ET compared to MPH shows efficiency. I was told a long time ago that a good place to compare your results is the NHRA Stock Eliminator Record Page. https://www.nhra.com/stats/class_indexes. Go to this page. Find a Stock Eliminator record that's around the same ET or MPH as you are running and see how you compare. (It's at the bottom of the page) Make sure the car/record you compare to is one of similar weight. The Stocker guys typically run a lot of gear, and have their cars well sorted. If they're on the record page, that's a very good place to start.

I was out in my Road Runner last weekend at Maple Grove in PA. In street trim it ran 11.52 @116. My 60 foot times were 1.66 most of the day. Your 1.6 times are pretty good for a heavy B-body without a lot of power. I'm guessing I have roughly 500 HP at the wheels. It's torque that moves them though...not HP!

 

[Frustration]

...out of curiousity, and 'cause I know next to nothing about England...what's the altitude at the track where you run? High altitude and hot humid weather=not good for racing, and it'll cost you MPH and ET.

 

[33 IMP]

It looks like your car is pretty well sorted out. If your ET is high, and MPH is low, that is an efficient combination. MPH is a way to measure HP. ET compared to MPH shows efficiency. I was told a long time ago that a good place to compare your results is the NHRA Stock Eliminator Record Page. https://www.nhra.com/stats/class_indexes. Go to this page. Find a Stock Eliminator record that's around the same ET or MPH as you are running and see how you compare. (It's at the bottom of the page) Make sure the car/record you compare to is one of similar weight. The Stocker guys typically run a lot of gear, and have their cars well sorted. If they're on the record page, that's a very good place to start.

I was out in my Road Runner last weekend at Maple Grove in PA. In street trim it ran 11.52 @116. My 60 foot times were 1.66 most of the day. Your 1.6 times are pretty good for a heavy B-body without a lot of power. I'm guessing I have roughly 500 HP at the wheels. It's torque that moves them though...not HP!

Of course you must remember that the typical goal in stock eliminator is to run a full second under your classes index. The record might not reflect what these stock elim cars can really do!

 

[dvw]

Super/Stock and Stock eliminator is a whole nother animal. BIG gear, LOTS of converter, and HIGH rpm. But to get an idea log on to NHRA results. Go to the qualifing results from this weekends Chevrolet Nationals at Indy. Every stocker (170 of them) has its runs listed with all the incrementals. You will be surprised as some 60fts in the same class may vary .10. This is the best of the best, so it's not as easy as it seems. While you're at it go to Super/Stock and the Factory Stock shootout. As I stated before. The original posters ET/MPH match pretty good. Dyno's vary so who knows on the power. Might be correct, might not. I'd start with the shorter tires.
Doug

 

[33 IMP]

just been on wallace calculator, and iv put in all the variables, tyre height, rear ratios and the one thing that makes the biggest difference on MPH is shift time, so im going to increase my shift light, thats a start.
29" tyres help trap speed and keep 60 foot
my head hurts lol

Does your track have intermediate timers, what are your 330ft/ 660ft times? If your mph improvement from 660ft to 1320ft is less than it should be, you may be laying down at the big end.
I would post my typical numbers as a comparison but i'm out of state right now and don't have access. I do know my best ever 60ft was 1.59 and typically 1.65 for a mid 11s car, 11.11,122 best.
Edit: usually ran an old 850 double pumper on a tm7, but best e.t. was with two 750 carters on a crossram. Back to back , the crossram combo was no faster than the tm7/850 combo, tm7 welded up for max wedge window.
See if you can borrow a known good 850 or 950 and give it a try!

 

[mopar 3 B]

Et will get you there first. To many get hung up on mph.