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 Post Posted: Sat Nov 22, 2008 4:47 pm 
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Location: NW MO.
I've chased shift points around, and recently tried lower again, and et was lower too.
I tried a different gear (5.86) and it was actualy a little faster with that gear, but it was on my 7000rpm rev limiter about 100' from the finish line, and 7000 seemed high enough. If it don't go 6.99 this week, I'll go back to that gear, and take the rev limiter out, and try again.

As for MPH, it will always be a little low for the et, when you are chasing just low et. Improving finish line MPH, for a loss of 60' time, will almost always hurt ET.

This week I installed new 90/10 shocks, replaced upper a arm bushings with some that allow the a arm to rotate freely on the shaft, lowered oil level 1/2 QT, and retarded the cam timing 4* more. It's now installed at 116* intake centerline, was 112*.

Well?? 6.99??? Anyone think I helped, or hurt ET???

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Last edited by randy355 on Sun Nov 23, 2008 8:00 pm, edited 1 time in total.

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 Post Posted: Sat Nov 22, 2008 6:11 pm 
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What is the weather going to be? I think you have a shot. I don't know about the timing adj. is the car pulling on the big end or id it kind of leveling out?

Jake ran a 6.998 on a 1.528 60' but he has also ran a 6.999 with a 1.519 60'

Try staging really shallow also.

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6.7772 @ 101.51 1/8th 10.747 @ 122.24 1/4

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 Post Posted: Sun Nov 23, 2008 7:56 pm 
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Well I guess you can run a 6.99 with those simple engine parts.

Today, at KCIR it ran a 6.990 @ 96.33 MPH.

I'll weigh it tomorrow.

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 Post Posted: Sun Nov 23, 2008 8:22 pm 
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Good job Randy.  I ran some new bests at Mokan today too.  111.08 in the 1/8th and 138.25 in the 1/4.

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 Post Posted: Sun Nov 23, 2008 8:43 pm 
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Congrats, I knew you could do it.


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 Post Posted: Sun Nov 23, 2008 11:05 pm 
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Way to go Randy.  \:D/  \:D/  \:D/  \:D/  \:D/  \:D/  \:D/  \:D/  \:D/ What changed?

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6.7772 @ 101.51 1/8th 10.747 @ 122.24 1/4

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 Post Posted: Sun Nov 23, 2008 11:24 pm 
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WR169 wrote:
Way to go Randy. What changed?


This is what was different from last week.

randy355 wrote:
This week I installed new 90/10 shocks, replaced upper a arm bushings with some that allow the a arm to rotate freely on the shaft, lowered oil level 1/2 QT, and retarded the cam timing 4* more. It's now installed at 116* intake centerline, was 112*.


I guess ET hunting is over for this year!

ET is SO much more elusive than other prey!!

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 Post Posted: Mon Nov 24, 2008 7:21 am 
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I check a web site for density Altitude for your track for yesterday and the week before. yesterday the DA was between 286 at 12pm and -156 at 6 pm. Last week was -433 at 12pm and -457 around 6pm. It was pretty cold on the  15th wasn't it. =; 39 for a high  O:)

I wonder which change made the most difference.:-k

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6.7772 @ 101.51 1/8th 10.747 @ 122.24 1/4

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 Post Posted: Mon Nov 24, 2008 2:04 pm 
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WR169 wrote:
I check a web site for density Altitude for your track for yesterday and the week before. yesterday the DA was between 286 at 12pm and -156 at 6 pm. Last week was -433 at 12pm and -457 around 6pm. It was pretty cold on the  15th wasn't it. =; 39 for a high  O:)

I don't think the air was that good. It got warmer than 39 last week.
Look up the weather for Lees Summit MO. That's the closest reporting station to KCIR.

WR169 wrote:
I wonder which change made the most difference.:-k


I had ran it with less oil before, and didn't realy see any difference. I just thought that was one thing that wouldn't hurt. If nothing else it remover 1 lb. from the car.
Since the 60' wasn't any better, I don't think the shocks made a big difference.
My thinking is retarding the cam is what helped the most. When Rick, and I dynoed this engine before, we saw a trend of the same power before peak power, and more after peak power, by retarding the cam.
My opinion is, with the very limited duration, it simply helps to hold the intake valve open more at/after BDC, than it hurts to not have it open as much near TDC. I also belive the latter EX valve closing is a positive. Holding the ex valve open later near the end of the ex stroke, helps more than opening it later hurts. The headers are too big, and too short for the combo, so having more ex valve window area exposed to the port/header late in the ex stroke, helps when the rpm gets well past peak where the headers are tuned for.

My engine program shows 77 more peak HP for this engine, with the correct solid lifter flat tappet cam, and no other changes. I'm not sure there's that much power left with just a cam change, but it gives you an idea of how under cammed this engine is.

It would be interesting to hunt down the lowest ET possible now, with only cam changes. Everything else must remain the same, and just cam swaps, and pushrod length, only to keep geometry the same.

So what would be the best cam?? :-k

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 Post Posted: Mon Nov 24, 2008 4:33 pm 
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http://www.dragtimes.com/da-density-alt ... ather+Data

That's the link for the DA. It gets it from the closest weather reporting station/Air port.

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 Post Posted: Mon Nov 24, 2008 6:02 pm 
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randy355 wrote:
I'll weigh it tomorrow.


I guess I was better at getting weight out than I thought.
It weighs 2830lbs, with me in it.

I think that diminishes the sucsess of the 6.99 time. :-({|=

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 Post Posted: Mon Nov 24, 2008 7:30 pm 
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randy355 wrote:
randy355 wrote:
I'll weigh it tomorrow.


I guess I was better at getting weight out than I thought.
It weighs 2830lbs, with me in it.

I think that diminishes the sucsess of the 6.99 time. :-({|=


I don't think it does.  I ran as quick as 7.10 @ 96 in my '40 and really would have liked to have got a 6.99 out of it.  It's a bit heavier at 3300 lbs though.  Maybe I shoulda dumped some weight!

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 Post subject:
 Post Posted: Tue Nov 25, 2008 6:15 am 
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randy355 wrote:
randy355 wrote:
I'll weigh it tomorrow.


I guess I was better at getting weight out than I thought.
It weighs 2830lbs, with me in it.

I think that diminishes the sucsess of the 6.99 time. :-({|=


I think not.. To get that out of that combo is just crazy to me.
I have a friend who has an S10 with a 355 and ported Holley Aluminum heads, glide 4000 stall who has only ran 7.27 at about the same weight.
He really wants 6's and I think it should but...
You did a great job with your combo!! \:D/  \:D/  \:D/  \:D/  \:D/

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 Post subject: reply
 Post Posted: Tue Nov 25, 2008 10:52 am 
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Randy,

Great job with the parts you used to obtain the 6.99 et. =D>  =D>  =D>
Now, just imagine(financially available mind you) that same engine with a light weight crank, light rods, a little higher compression, and some more head work and a cam change could do for it! O:)  I know, what's the point, no point, just would be cool to see these changes and then rip a 6.teen at that point?  I like your cam swap for more power thought also, this would be a great  mag. article for somebody.  You know, instead of swaping cams, you can also try different rocker ratio's and vlave clearances to find out what this engine wants exactly!!!!!! Lots of engines will tell YOU what they want by changing valve clearances and you may be surprised!!!!  Again, good job on reaching your goal, now try a big block and go have some real fun =;  \:D/  \:D/  \:D/

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 Post subject: Re: reply
 Post Posted: Mon Dec 01, 2008 7:16 pm 
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Elkyman wrote:

 Again, good job on reaching your goal, now try a big block and go have some real fun =;  \:D/  \:D/  \:D/


That's what I told the guy with the 434 and he agreed!   \:D/

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