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Discussion Starter #1
Ok i have a Racepak sportsman with an 02 sensor, reading avg is in the 10.8 range. When the second kit comes on. I hate posting my exact tuneup but i will. (The first is a plate 10 spread and 5.2 fp. The plate must be close because the afr is in the 12 - 13 range until the second one comes on.) Timing is 22, second is a fogger 4 spread and 5.8 fp, timing down to 13 with both on.
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i know this is fat and yea the plugs are dirty. I cant see any heat on the straps at all and they are still there after a pass. Car picks up solid 30 in the back half, some times 31 based on air density

I do not have a weather station yet.

What direction do i go to safely clean this thing up??

Lower fuel psi .5 ?
Add timing?

Thanks
 

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If it were mine..I would leave timing...and add spread on 2nd stage till it cleans up..like 8, to get it to..12 to 1 range..it will probably haul more ass too
 

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X2. ^^^^ IF you want more power in the tune add NOS jet too it and clean it up that way. Just an option.
 

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Ok i have a Racepak sportsman with an 02 sensor, reading avg is in the 10.8 range. When the second kit comes on. I hate posting my exact tuneup but i will. (The first is a plate 10 spread and 5.2 fp. The plate must be close because the afr is in the 12 - 13 range until the second one comes on.) Timing is 22, second is a fogger 4 spread and 5.8 fp, timing down to 13 with both on.
.
i know this is fat and yea the plugs are dirty. I cant see any heat on the straps at all and they are still there after a pass. Car picks up solid 30 in the back half, some times 31 based on air density

I do not have a weather station yet.

What direction do i go to safely clean this thing up??

Lower fuel psi .5 ?
Add timing?

Thanks

This can be the usual debate about timing, jet spreads, fuel pressures, and A/F numbers... Everyone will have an opinion. But really on the limited info, it's tough to answer correctly in my opinion..

To just say you have a plate with a 10 spread and a direct port system with a 4 spread is relatively open ended. A plate with a .045 nitrous jet on a .010 smaller fuel may not be bad. But a plate with a .120 nitrous jet and a .010 smaller fuel is a piggy..

Same goes for the direct port a .024 nitrous jet and .004 smaller on fuels not terrible. but a .044 and a .004 smaller fuels a different story as well..

Here's what I can tell you, the size of each tune plays a part here. based on the size and the timing numbers is really what holds the real answers.

I see to many getting caught up in pulling all there timing out and wondering why their A/F numbers will never get right.. :confused: As I have said before many times, it's not just about the N/F ratio, you still have to have the timing in the proper window for YOUR combo for all to jive correctly. SJ
 

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Discussion Starter #5 (Edited)
ok Steve........lol

plate is 71 61

fogger is 32 28

carb looks to be very close 12-13 afr in the burnout and staging 14 -15 on the trans brake (lean)?

Im just looking for general ideas, not a set in stone tune, and certainly not looking for a debate on rich lean etc lol
 

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Discussion Starter #7
add nitrous...its not all about heat in the straps, watch mph too
Well SIR....adding N20 is fine to spot you or run that Monte....LMAO

BUT im looking to dial this car into an 8.5000

Saturday i ran an 8.58 cutting gas WAY early...8.58 @ 143
Sunday after an adjustment in the progressive i go 8.56 to the stripe

the air changed what , 1500 feet, by first round and i go an 8.70 ??? First time i "tree" anyone, i had an .060 advantage on the tree and get run down to lose by .015 !!! Oh well

Joe i was hoping to run into you all weekend , want to talk to you about 25-5 my car. I will try to call this week, thanks
 

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Well SIR....adding N20 is fine to spot you or run that Monte....LMAO

BUT im looking to dial this car into an 8.5000

Saturday i ran an 8.58 cutting gas WAY early...8.58 @ 143
Sunday after an adjustment in the progressive i go 8.56 to the stripe

the air changed what , 1500 feet, by first round and i go an 8.70 ??? First time i "tree" anyone, i had an .060 advantage on the tree and get run down to lose by .015 !!! Oh well

Joe i was hoping to run into you all weekend , want to talk to you about 25-5 my car. I will try to call this week, thanks
Then pull fuel out...I saw you by your pit but you looked busy under the hood so I left you alone
 

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ok Steve........lol


carb looks to be very close 12-13 afr in the burnout and staging 14 -15 on the trans brake (lean)?
If you are on the 2-step on the 'brake, then the wideband will read lean (misfires/raw fuel shows lean on the sensor)
 

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Discussion Starter #10
anyone have any exp cleaning up a tune thats in the 10-11 range what amount of jet did it take? .002 ? .004? i understand its trial and error
 

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The nitrous guy
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2 points on an A/F, is a LOT. That will require a pretty serious change. A pound of fuel pressure won't begin to touch that. I suspect that if you keep the same .032 nitrous jet, you will end up with a .024 fuel jet, in the 4.5-5.0 range, to get what you want. Not saying you should go straight there, just saying thats where I think you will end up.

Monte
 

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Tony,
I would agree you need to work on cleaning up the fuel side but you may also be a little light on timing too ?? Both will effect the A/F numbers.. If I were you, I would just make small steps and watch the numbers and plugs. SJ
 

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Discussion Starter #13 (Edited)
Well i have been down this road before, first problems i had was i was not pulling the timing with the second kit like i thought. Then i had some mechanical interferance with intake valves and pistons in the radial part of the notch. Now armed with the racepak data i can see a lot easier whats happening as i make these changes.
The car is back to within .18 of what it ran with an 8 spread.....
NOW i can sneak back up on that 8 spread and see AFR as well as plug readings and Pan Vac and keep a good handle on whats going on
PLUS...baby steps for sure. May take me a while but .5lb fuel psi adj and .5* timing adjustments this time. The car is running well again and im not making drastic changes, just little ones

Let me put this into perspective for you.....
i made a couple passes with the timing at 20* with BOTH kits on......

yea i think the timing might be light right now, but as i lean it out it may come right into line.

thanks for all the advice
 

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I have question to add to this subject. I understand that taking baby steps should be the safest way to approach this. On the other hand if it takes to long to get it cleaned up wouldn't that cause damage as well? I feel like there has to be a balance between the two. Or maybe we just go with "the based on experience" theory.. Maybe Steve or Monte could help clarify this some.

Thanks
jl
 

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EFI/N2O JUNKIE
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Tony, put a BIG ASS vacuum gauge on your dash right in front of you, lean that thing out to where it should be, pull 4 more degrees to be safe, and make a pass. If you see the vac gauge swinging-around GET OFF, otherwise keep your foot down and see what a FRESH plug looks like. I am sure you know which cylinders are the hottest in your engine, concentrate on them first. Our fire gloves make swapping a plug on the return road pretty easy. If your A/F is reading correctly and it is in the 10's your plugs should be black or close to it. You need to change fuel jets (smaller) or nitrous jets (larger), changing fuel pressure is not going to do a thing for you where you're at right now.
 

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Discussion Starter #16
Mike i have pulled plugs on the return road. They come out a little "tan" looking. Semi clean but not CLEAN. Certainly they are fat.
When i had an 8 spread they came out like they were right out of the box.
I want to race two things next year, some 8.50 races and some heads up stuff, so i much rather add nitrous jet to clean this up and then slow it down with the progressive delay timer.
 

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id pull fuel jet out till it cleans up on 1st system first ,and do the same with the second and watch the strap for heat and timing mark slow steps passes are cheaper then pistons
 

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I don't try to eliminate the fuel ring on my plugs, I like to see something there. I try to get it light-colored and thin, but I don't chase it much. My porcelain is completely white until you get down inside, then I can see a thin black (sometimes brown) ring. If your porcelain is colored all the way to the end, you have too much fuel and/or too cold of a plug. With the power you are making you should be able to keep a -10 clean. I see no need for a -11 with your engine, but I know there are others that would do it.

So, add nitrous jet and pull some timing. Make a pass with a fresh plug or two, pop em out and see what they look like.

I am serious about the vacuum gauge, it will start to flutter when you go too far!
 

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Discussion Starter #19
I don't try to eliminate the fuel ring on my plugs, I like to see something there. I try to get it light-colored and thin, but I don't chase it much. My porcelain is completely white until you get down inside, then I can see a thin black (sometimes brown) ring. If your porcelain is colored all the way to the end, you have too much fuel and/or too cold of a plug. With the power you are making you should be able to keep a -10 clean. I see no need for a -11 with your engine, but I know there are others that would do it.

So, add nitrous jet and pull some timing. Make a pass with a fresh plug or two, pop em out and see what they look like.

I am serious about the vacuum gauge, it will start to flutter when you go too far!
Mike i am logging the pan vac right now and yea it drops during the pass. Im sure because its rich. There is usually no or only like 3 drops of oil in the can after a pass. You know i have hurt stuff and haha i know how much oil comes out then ! !
 

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The nitrous guy
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I have question to add to this subject. I understand that taking baby steps should be the safest way to approach this. On the other hand if it takes to long to get it cleaned up wouldn't that cause damage as well? I feel like there has to be a balance between the two. Or maybe we just go with "the based on experience" theory.. Maybe Steve or Monte could help clarify this some.

Thanks
jl
This is a great point and makes a lot of since. Tony already tried the 8 spread deal once, as he mentioned. The plugs were mint, the car hauled ass, but it hurt some parts as he mentioned, that turned out to be no fault of the tune. I can see being a little gun shy, but knowing that it has already run well there, I would likely go right back, knowing all those small issues were fixed.

Not trying to start the big rich/lean debate, but myself, I would much rather have it lean, as rich.............so yeah, I would make a big move

Monte
 
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