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70ss496

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Discussion starter · #1 ·
Well, I started trying to look at my time slip and needed some suggestions on where to go from here. I keep good records of every pass, so ask if more info is needed. Here's what I was trying to figure out, by looking at an 1/8 to 1/4 conversion chart my car should be going 11.40-11.45?? So what I'm wondering is if I'm losing more on the top end than I should be or if this is normal and these charts are crap! Heres my best slip so far(8th pass in car ever).

60' 1.618
330' 4.775
1/8 7.461
MPH 90.89
1000 9.802
1/4 11.795
MPH 113.23

shifted @ 5500
left off of a 1000rpm idle
42 lbs in front tire
14 lbs (cold) in rear slicks, usually 15.5 to 16 after run
36 total timing, 20 initial

This was my best run that day, car was going 11.87-11.91, the only difference was that I staged at 160 degrees instead of 180. Has anybody picked up ET by keeping the car at 160?

I notice I'm picking up 22.34 MPH on the top end. Is this normal or should I be gaining more.

If not normal:

Am I shifting too low?
What can be done to help this pick up more on top end.
I'm running a 3" paper element in a stock chrome air cleaner, thought that may be hurting me?

Sorry this is so scatterbrained, just trying to see if I'm missing anything and looking for any and all suggestions as to pick this thing up some more. I ordered my Lift bars and air bags, so hopefully that stuff will help a lot on the launch.

Thanks in advance for everybody's help.

Matt
 
With your mph I'm thinking you are pretty close to maximum performance for your current tune up. Have you tried leaving at a slightly higher rpm,maybe 1500? and tried shifting at 6000 rpm? I pick up 22-24 mph from the 1/8 to 1/4 also. Mine has run a best of 11.78 @ 114.5 mph.

1.66/7.47/11.78 were the incrementals that I do remember on my best pass.
 
Discussion starter · #3 ·
Robert, thanks for the quick reply, no I haven't tried shifting higher, what do you shift yours at? I'm going to the track next Friday with my new lift bars and air bags. I was going to play with those shifting the same so I could get a new baseline, the put another chip in and try shifting at about 6300. Yes, I've left at higher rpm's leaving off idle get my best 60 foot. leaving at 2000 rpm it 60' was 1.74. Best off idle is a 1.60. This is all on stock suspension so I'm hoping with the little suspension work I'm doing will help some. Thanks again,

Matt
 
Matt,
Don't know what charts you are using but if you use .80 for mph & .64 for et conversions you will be about as close as you can get for a generic math answer.
Divide your 1/8 for 1/4 & multiply for the 1/4 to 1/8.
IE: 7.46/.64=11.66.
91/.80=113.75
 
I leave at 1500 and shift at 6000, I think :confused: We've been rained out so many times this year,I'm not sure :D Its looking good for this saturday though
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Have you checked your fuel pressure down track? It looks to me like you are losing a little on the big end,with a quicker 60,ahead at the 1/8,then slightly slower at the end as compared to my best,since you are running lower gears I'd expect you to be quicker at the start,just seems you might be running out of steam on the big end.
 
I picked up 2mph the last trip out by removing the air cleaner. Give it a try and see what it does for you. The rest of the numbers look to be about where you should be.

Troy.
 
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Hi Rapid Robert, I know from your posts that your weather in southwest Missouri is just about the same as ours in the Tulsa, Ok. area. Guess what, rain predicted both friday and sunday as well as all next week, good for farmers but bad for Drag Racers. I've seen years where this 7 day rain cycle went on for 12-13 yeeks in a row. Guess we had better get ourselves a boat, huh.
 
70ss496, All your numbers seem about right to me. Actually 22-23 MPH in the second 1/8 mile is pretty good. My sons 9 second Chevelle doesn't gain much more than that on the motor runs, (about 27).
 
I'm building an ark Harold :D Actually its looking better for here, down to 10% chance friday and saturday with a little dryer air...I am ready,new upper and lower ball joints,tie rod ends and alignment was done tonight. I wanna race!!! The midwest regional is in town this weekend too and I'll probably miss it cuz I'll be at the track. Sorry Matt...didnt mean to hijack your post.
 
Discussion starter · #11 ·
Thanks for all of the suggestions and thoughts, hopefully it will run better with some more tuning and my litte bit of suspension work. They just changed yesterday the heads up class I race in to an indexed class with my index being 11.40. I need to go faster, it just takes time and MONEY! Thanks again guys,

Matt
 
First, the 22-23 mph increase from the 1/8 to the 1/4 is right where it should be for your car. In fact, most cars in this performance range are right in that ball park. My Nova goes 98/120. Even my little Quad 4 Calais goes 75/97.

When I used to run my 70 Chevelle, I made the cowl hood functional. It wasn't the flapper valve model, just the standard one. Anyway, with the carb sealed to it and no air cleaner, it was good for .2 sec and 2mph every time compared to a 3" open paper element. I often had to run with the air cleaner on cause the car would sneak into the 11's and had no roll bar.
Good luck with the new suspension pieces and with the weather.
Ron
 
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Hey Matt,

Here's a combo of tug boat action for you. I have a 72 Elkymino with a 454, 13:1 oval heads, 830 dbl pump holley, glide with stock 1.76 gearset, 5000 stall conv.4 in. driveshaft, 12 bolt with 4:10 gears, Hoosier quick time pro 29x11.5x15.
Fuel cell & batt in the bed, dragrace anti roll sway bar in rear, front removed. airbags solid mounts except for trans., 3 way shocks up front and QA1's in the rear. Car/ ooops, truck lifts the left front skinney and runs 11:79 @116 mph.
Now, if you have a Holley Blue pump like I did due to cost cutting, loose it, the volume is just not there. Also, make sure you have #8 or larger fuel line to the front with #6 to the carb. psi should be around 6-7 psi. My tire psi was in the 12 to 20 ranges to see what it liked, but the fuel system needed help. It yanked both skinneys this time but seemed to still be caged and wanting to be let loose. After a gear change to a 4:56, the car only went 11:59 @ 118 mph, still a fuel problem, now I have an Aeromotive 140 gph pump and a 850 drag race Holley special and the throttle respons came alive like a top fueler, well, almost, and the volume is there. I am going out over the 4th holiday to try the new combo out and if you are interested, I can send some input bact to you. What kind of head ports and cam are you running also, I just love this sport, man against machine, forget going left, hard enough going straight with 600 hp
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I would have thought you would go faster too, I have a glide & you a th400, you should be showing daylight?, how much does it weigh? Mine is 3650 with me in it, remember, I have an Elcamino with a bed, and if I can yank em with a glide, I know you can with a 4oo. Got a roll cage or any special tubing? I launch around 2000-4000 rpm, shift @6600 and cross the traps @ 7000, just like I built it to do, but now I want more cam & heads to go faster, or loose more weight!!!
Let me know what you think and we can chat again. Here is a pic of my elky from New Jersey at the Pro Edelbrock race event . Enjoy
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John G. "The Elkymann"
O/C 9900

Looks like I can't post a pic without a site, but you can e-mail me and I I can send it asap, it's cool too.
 
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