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What Will It Run?

@dvw is the 440-25 the same as
440-I4-25? That seems to be an "i" but capital "I" not "1" in the part # and I've seen the intake, it looks the same...
 
Well, the results are in. It was definitely an improvement, but not as much as I expected. Maybe I just need to do some more tuning and figuring out shift points with the new combo. It was a pretty warm and humid day with temps around 90. DA was between 1900 and 2500 feet. As a point of reference, my old personal best was 10.741.

1st run with the 410 primary jets and 398 secondaries:
60' 1.495
330 4.311
1/8 6.755
mph 99.77
1000 8.899
1/4 10.737
mph 121.80

Plugs looked a little lean so rejetted the secondaries to 404.

60' 1.486
330 4.293
1/8 6.716
mph 100.75
1000 8.841
1/4 10.665
mph 122.80

Plugs still looked lean, so rejetted the primaries to 416, I also bumped my shift points from 6000 to 6500

60' 1.465
330 4.277
1/8 6.694
mph 101.02
1000 8.814
1/4 10.635
mph 122.81

So this manifold picked up .11 over my previous best. I think this should be better. In addition to the manifold, the previous best (10.741) was will the old solid flat tappet cam, I have since upgraded that to a solid roller....specs in post 126. I was really hoping to be sub 10.50. Am I off in my jetting? Shift points? Timing is locked at 35*. Launch rpm is at about 2500rpm.
 
Attached is a log of progress and changes made over the past year or so.
 

Attachments

  • timslips.pdf
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Well, surprisingly the new intake manifold, with its larger plenum and runner volume, didn’t seem to hurt the 60’ times......... however if the goal is sub-10.50 passes, you’re still looking for enough of a power gain to get you into the 126+ mph range........about 50-60hp more.
 
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If your launching at the same rpm as before. But you have larger plenum and runner volume the your air velocity is slower. Maybe it might like a bit more launch rpm.
 
My two cents, you need more compression and cylinder head porting to get where you want. My cranking compression is 215-225 psi with 272/276 camshaft. My heads are 65cc's and with flat top pistons about .015 down the hole.
 
Well, the results are in. It was definitely an improvement, but not as much as I expected. Maybe I just need to do some more tuning and figuring out shift points with the new combo. It was a pretty warm and humid day with temps around 90. DA was between 1900 and 2500 feet. As a point of reference, my old personal best was 10.741.

1st run with the 410 primary jets and 398 secondaries:
60' 1.495
330 4.311
1/8 6.755
mph 99.77
1000 8.899
1/4 10.737
mph 121.80

Plugs looked a little lean so rejetted the secondaries to 404.

60' 1.486
330 4.293
1/8 6.716
mph 100.75
1000 8.841
1/4 10.665
mph 122.80

Plugs still looked lean, so rejetted the primaries to 416, I also bumped my shift points from 6000 to 6500

60' 1.465
330 4.277
1/8 6.694
mph 101.02
1000 8.814
1/4 10.635
mph 122.81

So this manifold picked up .11 over my previous best. I think this should be better. In addition to the manifold, the previous best (10.741) was will the old solid flat tappet cam, I have since upgraded that to a solid roller....specs in post 126. I was really hoping to be sub 10.50. Am I off in my jetting? Shift points? Timing is locked at 35*. Launch rpm is at about 2500rpm.
The 10.74 you ran was in 500Da versus 2500 for this trip. Thats a few tenths and mph right there. Also, as you already know, its a lot of little things that add up in the end. I would bet with a little jetting, timing, shift point, squirter nozzle you will be much much faster than before especially if you get that 500DA again. I thoroughly enjoyed this thread. Super cool car.
 
I usually ran my jetting at 113P/110S .047 rod with 750 Eddy's on that manifold.
Doug
 
The 10.74 you ran was in 500Da versus 2500 for this trip. Thats a few tenths and mph right there.

For sure the car will pick up in better weather.

But if the goal is to be able to run 10.20’s in the weather that the car currently runs 10.70’s in....... he’s still looking for a fairly healthy bump up in HP.
 
For sure the car will pick up in better weather.

But if the goal is to be able to run 10.20’s in the weather that the car currently runs 10.70’s in....... he’s still looking for a fairly healthy bump up in HP.
Last trip out, I went 10.63. My short term goal is to cover the 10.50 index. That would mean consistently in the 10.40's and then slow down from there. Long term, I would like to get to the 10.00 index. I realize that will take a lot more work to get to.
 
The short answer is....... you’re still looking for about 40hp.

Going by the Moroso chart, your ET is already better than the MPH(ET shows a better HP/lb than the speed).

My take on the car not responding as much as hoped to changes made in the quest for more power is(cam & manifold) that whatever the real “problem” with the combo is(the “cork”), hasn’t been addressed yet.
 
Spent today at the track in Bradenton...It was a day of Highs and Lows. It was COLD this morning, 32 degrees when I left the house at 8am. Mid 40's by the time I made my first hit. Right off the line, my throttle cable came disconnected. A long idle down the track :-(. Second run was nothing to speak of with a 10.804 @ 121.03. Prior to the 3rd run made a small adjustment to fuel pressure and put another couple degrees of timing in it (I had backed it off some when trying to fix and idle issue) to 34*. Felt real strong, but notice quite a bit of smoke out the back at the top end. Somehow I have developed a signifcant leak at the rear of the valley pan. We'll be fixing that tomorrow. Anyway run turned out to be a personal best by a big margin:

60' 1.465
330 4.246
1/8 6.631
mph 102.51
1000 8.720
1/4. 10.517
mph. 124.63

Getting close to the 10.50 index. Air was REALLY good with DA of -200ft
 
-200 D/A, I can't imagine air that good. My best run of 8.98 was at 2900D/A.
Doug
 
All of this important talk about "good air" reminds me of the weather in South Louisiana and Mississippi in the fall, winter, and spring. The several years that my car club rented a local drag strip, the event was held in the winter, when "bluebird skies" and cool/cold, dry air is abundant. Compared with the 90+% humidity and 85-90° temperatures at night in the summer, those beautiful days are great for racing.
 
Wonder what the ET difference would be vs the -200da?
This was the Mopar Madness race.

20220724_120845.jpg
 
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