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 Updated fuel system and jetting 
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Joined: Sat Jun 01, 2013 8:02 pm
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JayCampbell wrote:
A couple of things. I think you don't pick up as much as others in good air because you're already closer to optimum than the other guys. If they are too rich in bad air, they will definitely pick up more in good air. It's not just the carburetor either, a poor engine combination will benefit more from better air IMO. When you do something like change a shift point, it pretty much nullifies other changes you have made as far as being able to make a direct comparison from previous runs. I know you already understand this, just mentioning it. One thing I see in your graphs, that I see a lot is the rich dip right after the launch. It's from the pump shot, and you might be able to trim that down some and pick up a small amount in the 60'. You can sand down the yellow pump cams some to customize it, or you might be able to run the white cams as long as it doesn't cause a stumble. What I think you'd be looking for is a shot that is still strong at the beginning, but limit the overall volume. Might be a change more on one pump than the other, or might be changing both. Just have to try and see.vIgnore this if you've already been over that. :thumbl:



Jay
I was thinking about that yesterday too, maybe i am more closer to my tune and it doesn't swing as much, and I agree with that too about poor combos picking up better in better air conditions too.
I leave floored so my pump shot is gone by then on the 2 step, but yes I did grind the yellows a couple of years ago , only need to run .035's :)

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74 Firebird 3620 lbs
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Wed May 17, 2017 10:47 am
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KeyKeeper wrote:
Hmm, emulsion shouldn't have anything to do with idle IFR.



Key word shouldn't lol, But did only thing i changed

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Wed May 17, 2017 11:37 am
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Revved Up wrote:
Permatex High Tack Gasket Sealant:

https://www.permatex.com/products/gaske ... t-sealant/

Make sure the wheel lip is clean (brake cleaner). Brush the high tack on the tire bead, let it sit for a few minutes to start "tacking" and then seat the bead and inflate. Do not run the tire for 24 hours, to let the high tack cure. Finally, mark the tire above the valve stem, and watch for slippage. Most of the time, Radial slicks will slip a little, and find a spot where they will stay put. My slicks rotated quite a bit until I high tacked them. They moved a tiny amount afterward, and have not moved since.

That photo is incredible! I am including a link to Mickey Thompson's Tech Bulletin, so that you can read tire pressure guidelines. It may explain why your friend was able to drop so low on a radial. It has to do with tire diameter and vehicle weight. My tire is less than 30", and my car weighs 3000lbs.

Click on Street and Strip Tech Bulletins #3

http://www.mickeythompsontires.com/tech/

I apologize for spinning this thread into another discussion, but it is worthwhile information that will put you ahead of the game early. This will save you a lot of frustration, and in the end, you will be very happy that you switched over to a Radial. Dead hook is the goal with Radials.


I have a new set of 275/60 ET SS coming tomorrow,will get the high tack tomorrow also for the tire place. Probably wont run them this weekend, but will try them week after, local track is doing a radial race. Guessing ill have to tighten up ext to not hit tire as hard? ill try with my shock settings i have now of course first. How much burnout do they need?

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74 Firebird 3620 lbs
10.02@131.96 1.377 60 ft


Mon May 29, 2017 9:40 pm
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Location: San Diego, CA
The burnout depends on the track. At Barona where I race, the track gets greasy quick, so I do a fairly hard burnout. Nothing like the bias ply slicks, but a good hazing. Radials don't need as much normally. I do high gear only burnouts. I simply put it in third, hit the line lock, smack the throttle to 5000 RPM, and look for smoke to start showing in the rear view mirror. As soon as I see smoke, I let go of the line lock, and let the tires spin to within a few feet of the starting line. Feather it, and you will feel it grab. With tire pressure, they are very sensitive. Increase your tire pressure 2lbs at a time, starting at around 18psi. When the tires spin on the starting line, back it down 1lb at a time, until it hits solid every time. Radials will blow the tires off if the pressure is too high. Once they let go, it is nearly impossible to get it back. However, the increased stability on the top end, the increase in MPH, and consistency is unparalleled.

I have QA1 DAs in the front, and I have the shock extension set to 8. That is considered pretty high, but it slows down the front end enough to extend the apply time to the rear tires, and it is very very consistent that way.

I have CalTracs, set in lower hole, and 1 turn plus 1 flat of preload on the right, with 1 turn on the left. My rear shocks are Calvert, set at 7 on the left, 8 on the right.

That should get you moving in the right direction


Mon May 29, 2017 9:50 pm
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Revved Up wrote:
The burnout depends on the track. At Barona where I race, the track gets greasy quick, so I do a fairly hard burnout. Nothing like the bias ply slicks, but a good hazing. Radials don't need as much normally. I do high gear only burnouts. I simply put it in third, hit the line lock, smack the throttle to 5000 RPM, and look for smoke to start showing in the rear view mirror. As soon as I see smoke, I let go of the line lock, and let the tires spin to within a few feet of the starting line. Feather it, and you will feel it grab. With tire pressure, they are very sensitive. Increase your tire pressure 2lbs at a time, starting at around 18psi. When the tires spin on the starting line, back it down 1lb at a time, until it hits solid every time. Radials will blow the tires off if the pressure is too high. Once they let go, it is nearly impossible to get it back. However, the increased stability on the top end, the increase in MPH, and consistency is unparalleled.

I have QA1 DAs in the front, and I have the shock extension set to 8. That is considered pretty high, but it slows down the front end enough to extend the apply time to the rear tires, and it is very very consistent that way.

I have CalTracs, set in lower hole, and 1 turn plus 1 flat of preload on the right, with 1 turn on the left. My rear shocks are Calvert, set at 7 on the left, 8 on the right.

That should get you moving in the right direction


Thanks, Do U Know how calverts rear shocks adj? like you go higher on the number, does the ext tighten , but comp loosen? or they both tighten and loosen as u dial it up or down? I have afco DA in back and calvert 90/10 in front.

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74 Firebird 3620 lbs
10.02@131.96 1.377 60 ft


Tue May 30, 2017 9:01 am
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Joined: Mon Oct 21, 2013 12:15 am
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Location: San Diego, CA
The adjustment is for extension.

It has some effect on compression, but it is intended as controlling the extension of the shock. I try to keep the body separation to a minimum.

I adjusted the extension tighter until it had no effect on my 60', and left it alone. I did the same with the front, after I had adjusted the rear. I started soft on the front, got the rear sorted out, then adjusted the front.

It feels good every time it leaves the line, and I don't mess with it. I can play with the rear tire pressure, and get my starting line under control without messing with the shocks anymore.


Tue May 30, 2017 12:09 pm
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Ok, well I'm full loose right now and in the middle for comp, When I run these i'll try as is with 18 lbs and then go from there.

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74 Firebird 3620 lbs
10.02@131.96 1.377 60 ft


Tue May 30, 2017 8:09 pm
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