Bog off the line ? - Page 2

CJohnson · 08-28-2009, 12:19 AM

Quote:

Originally Posted by Jody Lang

I think your sec. spring is too light for your combination. Start your weekend out with the plain (stock) spring and be prepared to try a heavier one.

The heads might be a little big for your combination and might also need a bigger squirter to make up for lack of velocity.

Is this a #3310?

My bracket car has a 3310 on it. It runs mid 11s. Plain spring, 72 76 jets with a 028 squirter.

Good luck.

Thanks for your help Jody,

Ya this carb is a 3310. I will try the .037 squirters and a stock spring this weekend,

Thanks again.

cad · 08-28-2009, 08:55 AM

Your "bog" is very likely a lean condition like stated. Try the bigger squirters, AND make one change at a time, and keep notes.
Jody -- will the spring affect the launch much? I am thinking not much, if any. If anything, it will stay lean a little longer.
Clark Doukas

cad · 08-28-2009, 09:05 AM

Does the car idle well in gear?
Are the throttle blades manually adjusted to be open too far and uncovered the transfer slot?

cad · 08-28-2009, 09:28 AM

Last item I have is an article that talks about baseline setup, and the transfer slot:
http://www.carcraft.com/howto/77958/index.html

CJohnson · 08-28-2009, 07:04 PM

Well guys, changing the squirters was night and day difference, car launches way better with no stutter at all.

I tried it today the way it has always been set up and it went a 13.20 - 1.870 60 ft. and with just the .037 squirter change it went a 13.08 with a 1.840 60 ft. So im very happy with how it is launching now

Thanks for all the help !

Jody Lang · 08-28-2009, 10:57 PM

Clark, spring would definetely affect the launch. A bog from a too light spring can also cause consistency issues.

C, glad to hear you fixed it. If you have time this weekend or another weekend humor yourself and try that spring. It should help. Good luck.

CJohnson · 09-01-2009, 11:27 AM

Quote:

Originally Posted by Jody Lang

Clark, spring would definetely affect the launch. A bog from a too light spring can also cause consistency issues.

C, glad to hear you fixed it. If you have time this weekend or another weekend humor yourself and try that spring. It should help. Good luck.

Thanks Jody,

At the next test and tune I will try a heavier spring for sure.

Thanks,
Craig - C693

CJohnson · 09-22-2009, 05:52 PM

Jody, using the .37 squirter and your choice of 72/76 jets works like a charm on this carb and my set up !

but now at idle i am getting a "pop" every once in a while, does not seem to be affecting the performance or anything, just wondering what this could be ?

Thanks,
Craig

Jody Lang · 09-22-2009, 07:38 PM

one of your posts said you were going to put in a 7.5 power valve in place of the 6.5. you should be going to a lower #.

Check your vacuum at idle. Being a drag car you can use anything under the vacuum it idles at. 3.5 might be a good choice.

It sounds like a lean pop but it could be the power valve leaking too much fuel into the engine???

Have you tried a different spring yet?

CJohnson · 09-22-2009, 08:50 PM

Thanks for all your help jody

It is not a very big duration cam, i checked the vaccume at idle and im reading about 13-14, so I figure the 6.5 power valve that i have in now would be perfect ?
I tried a 7.5 power valve at mission on a test and tune friday and it did not like it at all, slowed more then a tenth.

Also, I have not tried a heavier secondary spring yet. Right now i have a "purple" spring.

08-28-2009, 08:55 AM	#12
cad Senior Member Join Date: Apr 2009 Location: Omaha, NE Posts: 673 Likes: 141 Liked 72 Times in 40 Posts	Re: Bog off the line ? Your "bog" is very likely a lean condition like stated. Try the bigger squirters, AND make one change at a time, and keep notes. Jody -- will the spring affect the launch much? I am thinking not much, if any. If anything, it will stay lean a little longer. Clark Doukas

08-28-2009, 09:05 AM	#13
cad Senior Member Join Date: Apr 2009 Location: Omaha, NE Posts: 673 Likes: 141 Liked 72 Times in 40 Posts	Re: Bog off the line ? Does the car idle well in gear? Are the throttle blades manually adjusted to be open too far and uncovered the transfer slot? Last edited by cad; 08-28-2009 at 09:22 AM.

08-28-2009, 09:28 AM	#14
cad Senior Member Join Date: Apr 2009 Location: Omaha, NE Posts: 673 Likes: 141 Liked 72 Times in 40 Posts	Re: Bog off the line ? Last item I have is an article that talks about baseline setup, and the transfer slot: http://www.carcraft.com/howto/77958/index.html

08-28-2009, 07:04 PM	#15
CJohnson Junior Member Join Date: Jul 2009 Location: .005 ahead of you Posts: 38 Likes: 0 Liked 0 Times in 0 Posts	Re: Bog off the line ? Well guys, changing the squirters was night and day difference, car launches way better with no stutter at all. I tried it today the way it has always been set up and it went a 13.20 - 1.870 60 ft. and with just the .037 squirter change it went a 13.08 with a 1.840 60 ft. So im very happy with how it is launching now Thanks for all the help !

08-28-2009, 10:57 PM	#16
Jody Lang Member Join Date: Mar 2002 Posts: 299 Likes: 28 Liked 81 Times in 25 Posts	Re: Bog off the line ? Clark, spring would definetely affect the launch. A bog from a too light spring can also cause consistency issues. C, glad to hear you fixed it. If you have time this weekend or another weekend humor yourself and try that spring. It should help. Good luck.

09-22-2009, 05:52 PM	#18
CJohnson Junior Member Join Date: Jul 2009 Location: .005 ahead of you Posts: 38 Likes: 0 Liked 0 Times in 0 Posts	Re: Bog off the line ? Jody, using the .37 squirter and your choice of 72/76 jets works like a charm on this carb and my set up ! but now at idle i am getting a "pop" every once in a while, does not seem to be affecting the performance or anything, just wondering what this could be ? Thanks, Craig Last edited by CJohnson; 09-22-2009 at 06:03 PM.

09-22-2009, 07:38 PM	#19
Jody Lang Member Join Date: Mar 2002 Posts: 299 Likes: 28 Liked 81 Times in 25 Posts	Re: Bog off the line ? one of your posts said you were going to put in a 7.5 power valve in place of the 6.5. you should be going to a lower #. Check your vacuum at idle. Being a drag car you can use anything under the vacuum it idles at. 3.5 might be a good choice. It sounds like a lean pop but it could be the power valve leaking too much fuel into the engine??? Have you tried a different spring yet?

09-22-2009, 08:50 PM	#20
CJohnson Junior Member Join Date: Jul 2009 Location: .005 ahead of you Posts: 38 Likes: 0 Liked 0 Times in 0 Posts	Re: Bog off the line ? Thanks for all your help jody It is not a very big duration cam, i checked the vaccume at idle and im reading about 13-14, so I figure the 6.5 power valve that i have in now would be perfect ? I tried a 7.5 power valve at mission on a test and tune friday and it did not like it at all, slowed more then a tenth. Also, I have not tried a heavier secondary spring yet. Right now i have a "purple" spring.