Carb/Nitrous guys come on in!

[slowgreen99]

Originally Posted by 1iron

Need to tune nitrous at the track. Shooting it on the dyno is not the same.

I see. We have pulled it back a few times though. I may bring the fourwheeler if I can make it out this weekend.

[WWhittle]

Originally Posted by 1iron

Need to tune nitrous at the track. Shooting it on the dyno is not the same.

I agree but you can do 90% of your nitrous tuning on the Dyno and then the final 10% at the track. Especially if you use someone like Tuten who has a ton of Dyno AND track tuning experience. You should be able to come off the Dyno with a tune that's pretty damn close for the track and then just check some plugs after a couple 330's to confirm. It's a hell of a lot easier to do that then to go make pass after pass after pass after pass trying to get your tune right.


Of course that's JMHO.

[WWhittle]

Originally Posted by slowgreen99

I see. We have pulled it back a few times though. I may bring the fourwheeler if I can make it out this weekend.

Everytime I've asked you if you were shutting off and pulling back to check your plugs you told me no!

[bwelch]

I have sat at the turn around at dorchester and swapped a couple plugs out so he could drive it back because we didn't have a 4wheeler. Everytime we pulled them they looked good. We dont shut it off every pass but once we know its good on that pill size and the weather we let it ride. 30 degrees of timing on a 150 and 28 degrees of timing on a 200. We even put a datalogging wide band it one weekend to see what the air fuel was on each pass.

[bwelch]

Originally Posted by WWhittle

Everytime I've asked you if you were shutting off and pulling back to check your plugs you told me no!

Brandon's grudge racing his tune up now!

[WWhittle]

Originally Posted by bwelch

I have sat at the turn around at dorchester and swapped a couple plugs out so he could drive it back because we didn't have a 4wheeler. Everytime we pulled them they looked good. We dont shut it off every pass but once we know its good on that pill size and the weather we let it ride. 30 degrees of timing on a 150 and 28 degrees of timing on a 200. We even put a datalogging wide band it one weekend to see what the air fuel was on each pass.

What does your fuel ring look like and where is the timing mark?

[bwelch]

The timing mark is in the middle of the ground strap and at the tip of the electrode. The fuel ring is a dark grey. It was a black at first cause the motor was running rich but we tuned it out. The fuel ring is down in the bottom not up top.

[WWhittle]

Originally Posted by bwelch

The timing mark is in the middle of the ground strap and at the tip of the electrode. The fuel ring is a dark grey. It was a black at first cause the motor was running rich but we tuned it out. The fuel ring is down in the bottom not up top.

Which cylider are you referring to?

[bwelch]

The middle ones are typically a little richer than the end cyclinders. 2,3,6,7 look as I described but 1,4,5,8 are the same timing mark but are more of a medium grey fuel ring. Not light grey though. I know light grey is bad for the motor.

[WWhittle]

That's pretty cool that with a standard ignition box y'all have the timing marks all in the same place- never seen that before.
Not sure what you mean by the light grey deal.
Keep up the good work!

[bwelch]

There aren't in the exact same spot but they are are from the middle to right before the bend. They are all within an 1/8" of each other and none of them have jumped to the threads instead of the ground strap. I talked to nitro dave some and he said that usually light grey can be a sign of pre detonation but I could have miss understood him. If you have any better info or if anything we are doing is wrong please help because we dont want to blow it up.

[slowgreen99]

Debating on running a -10 plug on the corners. Heard that was a good/safe thing to do without a good box. Any truth to that Wes? And yea, we're no experts, but just looking at "how tos" on yb and such, it seems the plugs look pretty spot on.

[WWhittle]

Originally Posted by slowgreen99

Debating on running a -10 plug on the corners. Heard that was a good/safe thing to do without a good box. Any truth to that Wes? And yea, we're no experts, but just looking at "how tos" on yb and such, it seems the plugs look pretty spot on.

If the corners look hot then yes but based on what bwelch said it doesn't sound like you need them.

[WWhittle]

Originally Posted by bwelch

There aren't in the exact same spot but they are are from the middle to right before the bend. They are all within an 1/8" of each other and none of them have jumped to the threads instead of the ground strap. I talked to nitro dave some and he said that usually light grey can be a sign of pre detonation but I could have miss understood him. If you have any better info or if anything we are doing is wrong please help because we dont want to blow it up.

I'm glad to help any time. I certainly don't know it all but I've learned plenty of shit the hard way and I'm half decent at tuning now. My car runs ok and I tune it myself now and have only burnt one piston. Lol.

[bwelch]

We are about to pill it up to a 200. We had it in when it broke but it only went 40ft. Most of the stuff we read on YB said thats its not really needed on a small shot but once you get to the 200hp and up range then most guys are running 10's in the corners. We will find out this weekend if the weather holds out.

All the info I gave you was on a 125 and a 150

[bwelch]

Originally Posted by WWhittle

I'm glad to help any time. I certainly don't know it all but I've learned plenty of shit the hard way and I'm half decent at tuning now. My car runs ok and I tune it myself now and have only burnt one piston. Lol.

This is my first nitrous carb car that I have tuned. we have been pretty lucky with Brandon's car because we haven't really had to change much on the tune besides carb jetting. We were lost at first trying to get the tune right. We went all the way to a 96 in the carb and it was still a little lean.LOL. Come to find out the fuel filter was clogged up with some gunk.

I think with the bigger shot we are gonna have some work ahead of us. I will pm you if we need some help. Thanks

[Chillerman]

Yall definitely have some work to do. I'm still trying to tune my nitrous woe's since I changed my plate.

You need to do some research on fuel (grades, octanes, etc.) and make sure your doing the right thing. I understand that race fuel ain't cheep, but neither is an overhaul if you grenade the motor. Wes knows what he's talking about when he says not to mix. Fuel density and burn/combustion rates are way different from one another. Any bonafied engine tuner like Tuten will tell you not to mix period.

[Darryl Buckner]

Yea, thats a fact don't mix fuels. I always hated the holley regulators cause they always creaped on me on the pressure. I run the Aeromotive SS pumps on the blue car 1 fuel and 1 nitrous and it works fine and no fuel creep. I did it cause the price of 2 Aeromotive SS pumps and regulators was about the same price as a new A2000 pump alone. Now on the LTD I run a rebuild A2000 from Donnie's old motor set up, and an Aeromotive SS pump for nitrous. I realize the A2000 would run it all but old habits..

[Matts94Z28]

http://www.yellowbullet.com/forum/sh...d.php?t=401685

[WWhittle]

I will post a screenshot of my Racepak datalog later to show ya'll how steady those holley regs hold fuel pressure. Pretty cool stuff.