First time at the strip!

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273 said:
Another way is to make more HP at the same or lower peak rpm your car will go faster there for need less gear, a shot of Nos and 3.23-3.55 should work.
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I have thought of putting maybe a 100-shot of nitrous in my car, I'm pretty sure I only gapped the top rings to .028" which is a bit on the tight side for nitrous with KB hyper-U pistons. Maybe later on when I'm OK with blowing my engine up but for now it's not really worth the risk.

And I'm curious, how long does it usually take to swap gears with an 8 3/4" like that? The one I'm putting in my car has 2.94 gears but I'll probably get a set of 3.55's to swap in for racing.
 
Swapping in a spare pumpkin/gears should take 1hr-1 1/2hrs.It,s the time jacking up the car,removing wheels and draining/refilling that takes up the most time.Maybe some smaller tires for the track would be easier.JMO good luck and have fun.
 
MOPEkidD-3 said:
And I'm curious, how long does it usually take to swap gears with an 8 3/4" like that? The one I'm putting in my car has 2.94 gears but I'll probably get a set of 3.55's to swap in for racing.
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If you get good at it, 45 minutes or less.

Helpful:

http://www.moparmusclemagazine.com/...n_plug_in_the_differential_housing/index.html

Since you have the 2.94, the clear choice would be to throw on 26" slicks and 3.55's on friday nights after work.

I'm starting to lean on going from 3.23 to 2.94 myself, keep those gears!
 
Quick bench racing question.
I have a 66 cuda, with a 36(5)/727 combo with 2.76 open gears in an 8 3/4 rear end, pretty close to what D3 has but without the tc. It has the 60403 cam instead of his 60401, and I'm assuming about 9.5:1 compression. I also have an Offenhause dualport single plane intake and a 1405 Eddy on a 1 inch spacer.
So close to D3 for the most part.

Would I be close to a dead stock 99 GTP in just a regular drag race? high 14, low 15 sec 1/4 mile and about 6.5 in the 0-60. It's got 240 horses and about 280 lbft of torque.
 
He might have you on that one, with your lower compression, bigger cam and single-plane intake it is probably pretty soggy off the line am I right? The converter makes a big difference in my car, when it flashes the engine jumps right to its peak torque and it pulls really hard no matter what gear you're in. Helps make up for the tall gears in back...
 
Yeah, however the cam really isn't all that bad. The engine guys said to go with a basically stock converter because of the gears. Now I wish I hadn't listened....
 
It could be that it was done at 5000 RPM because you don't have enough carb even at that elevation. Next time out make one of your passes with a open hole spacer. If you pick up over the previous pass, you could use more carb (or just run the spacer). A 770 SA would be a good choice for a 360.
 
It's equal to a 99 GTP on the freeway, until I get past 4k. Then it's better. Even though I lost 4-3
 
i think a 99 GTP runs around 14.80-15.00... so yeah not too shabby.
 
Hey guys I know we all love resurrected threads (har har)... Today I went to the drag strip again with a pretty different drivetrain combo and had some interesting results. Before I had skinny bald BFG banana skins with that stock rear end, now I have an 8 3/4 with 4.10 gears and sure-grip I borrowed from FABO member "nothingbutdarts" and 275/60-15 Firestone Firehawk Indy 500's on the back. I also replaced the mystery higher-stall TC with a stock unit which actually didn't improve the gas mileage like I had hoped but whatever...

About a month ago I made a couple runs with REALLY bad tire spin and could only muster a 15.8 @ 88 which annoyed me, that was worse than with the 2.76 gears and skinny tires! But today after I threw a 150-lb old tire filled with sand in my trunk and airing down the rear tires to 15 psi I was able to run a best of 14.9 @ 94 MPH. My main issue this time was with the carb, my old AFB got bad heat-soak and would lean out and bog halfway down the track until I sprayed the engine down good with some water. So next step for sure is tracking down a 750 cfm double-pumper, also want to cut a hole in the hood for a proper scoop and seal the air cleaner to it. After that I'm thinking of getting some good drag radials that are a bit shorter, and finally a bigger cam to move the torque curve up the RPM band.

EDIT: Also forgot to mention I weighed my car at the track and with me (150 lbs), that tire weight (another 150 lbs.), about 1/3 tank of gas and a bunch of random tools and shite in the trunk (maybe 80 lbs?) it was 3660 lbs. Does this sound about right? Where can I look to remove weight but not off the back end of course?
 
MOPEkidD-3 said:
Hey guys I know we all love resurrected threads (har har)... Today I went to the drag strip again with a pretty different drivetrain combo and had some interesting results. Before I had skinny bald BFG banana skins with that stock rear end, now I have an 8 3/4 with 4.10 gears and sure-grip I borrowed from FABO member "nothingbutdarts" and 275/60-15 Firestone Firehawk Indy 500's on the back. I also replaced the mystery higher-stall TC with a stock unit which actually didn't improve the gas mileage like I had hoped but whatever...

About a month ago I made a couple runs with REALLY bad tire spin and could only muster a 15.8 @ 88 which annoyed me, that was worse than with the 2.76 gears and skinny tires! But today after I threw a 150-lb old tire filled with sand in my trunk and airing down the rear tires to 15 psi I was able to run a best of 14.9 @ 94 MPH. My main issue this time was with the carb, my old AFB got bad heat-soak and would lean out and bog halfway down the track until I sprayed the engine down good with some water. So next step for sure is tracking down a 750 cfm double-pumper, also want to cut a hole in the hood for a proper scoop and seal the air cleaner to it. After that I'm thinking of getting some good drag radials that are a bit shorter, and finally a bigger cam to move the torque curve up the RPM band.

EDIT: Also forgot to mention I weighed my car at the track and with me (150 lbs), that tire weight (another 150 lbs.), about 1/3 tank of gas and a bunch of random tools and shite in the trunk (maybe 80 lbs?) it was 3660 lbs. Does this sound about right? Where can I look to remove weight but not off the back end of course?
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Gosh, for the altitude, weight and the warmth we had today that's not to bad!

Weight would mean: fiberglass and aluminum

How did it pull? Did it fall off early in the RPM? What RPM were you turning at the end of the 1/4?
 
You could start by moving the battery to the trunk, and a fiberglass front bumper.
 
nothingbutdarts said:
Gosh, for the altitude, weight and the warmth we had today that's not to bad!

Weight would mean: fiberglass and aluminum

How did it pull? Did it fall off early in the RPM? What RPM were you turning at the end of the 1/4?
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Hey Kim, I had problems early on with the carburetor leaning out and bogging at the big end of the strip in high gear. my last pass felt good overall, I shifted around 5300 rpm and hit the traps about the same rpm. The power didn't fall off too much by then but I have been shifting my 904 manually because I can't get it to stay in low gear coming off the line with the tires spinning.

I have seriously considered a fiberglass front bumper but I drive this car on the street a lot and would it not just fold up in an impact?
 
good improvement on time.
your car is definitely on heavy side. Mine all stock 72 318/904 duster weights 3200 all fluids full.
last year I got 15.9 time only improvement that car had was 8,1/4 sg rear and 3.2 gears.
Now car has 9.5 comp lunati 601 cam. Edel perf intake. Summit 600cfm carb. Rebuild stock heads with home porting, like show here in fabo. Haven't had change to get time but it feels really much faster. Trans is still all stock as is converter
 
Did the timeslip have the DA on it?

Compared to sea level if it was at 7K or above, you can take at least 10% off the ET and add 10% to MPH.

Got to make sure it pull all the way through.
 
nothingbutdarts said:
No strength for the street. Try the battery in the trunk then loose a little more ballast that you put in the trunk.

Have you ever rebuilt a Holley double pumper? 4779
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Good I'll leave the steel bumper on then... How big of a difference does moving the battery make?

I haven't rebuilt a Holley but I've watched a few YouTube videos and I'd definitely buy a book on them first. I'm also going to try to get one that was on a running car recently rather than one that sat on a bench or in the junkyard for 30 years I've dealt with others like that before and they aren't fun :wack:
 
MOPEkidD-3 said:
Good I'll leave the steel bumper on then... How big of a difference does moving the battery make?

I haven't rebuilt a Holley but I've watched a few YouTube videos and I'd definitely buy a book on them first. I'm also going to try to get one that was on a running car recently rather than one that sat on a bench or in the junkyard for 30 years I've dealt with others like that before and they aren't fun :wack:
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There's weight transfer going on if you move it to the trunk which will help a small bit plus if you then remove some weight from the trunk that you have in there the car will be a little bit lighter. Both those should help a tad in ET.
 
Something I thought of, the T-bars in the car are pretty stiff (1.0") I think if I jacked them up at the strip and made sure the toe-in was still good I would get much better weight transfer. When I launch the front end doesn't lift very much as the stiff bars don't need much preload to keep the front end suspended.
 
MOPEkidD-3 said:
Something I thought of, the T-bars in the car are pretty stiff (1.0") I think if I jacked them up at the strip and made sure the toe-in was still good I would get much better weight transfer. When I launch the front end doesn't lift very much as the stiff bars don't need much preload to keep the front end suspended.
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You want weak bars (low spring rate) with lots of preload on them for drag racing.

Think about this. Two springs, each 1' tall. One is 110# rate the other is 60#. You preload both of them so they are exerting 120# of pressure. The 100# will barely be compressed, the 60# will be 6" tall. Which one is going to launch itself when released? Stored energy.

Raising the front is opposite what you should do for drag racing. Except if you want the gasser look. If you have the front jacked up, there is probably 2-3" max lift available. You have to trim upper bumpers to get beyond about 4" with stock parts. Measure ground to front fender lip vertically through the spindle centerline. Jack up car via the kframe and see what that measurement is when front tires lift off the ground. That's the max lift you are going to see.

Problem most have is they want a good drag front end and not give up street driving, cornering manners. It's virtually impossible to have a 100% efficient drag front end and keep excellent street manners. Similar to the addage, jack of all trades, master of none. It's really not possible to be great in all facets. A tweener is being not good at anything.
 
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