Performance help - JeepForum.com

Reply
 
LinkBack Thread Tools
post #1 of 16 Old 02-01-2010, 09:40 AM Thread Starter
PoppaDucky
Registered User
1997 ZJ 
 
Join Date: Jan 2010
Location: Telephone, Tx
Posts: 118
Performance help

Howdy and thanks for any help/suggestions! I'm in a '87 yj with a 258 and ax15. Today I did a fluid change in the tranny and finally did the nutter bypass. I was amazed at the world of difference. The only problem is now my carb seems to be running super rich and idling at 1600 rpm. It's a weber 32/36 and I can't seem to find a diagram that says which screw is which. any ideas?
And also while i've got a thread going, Team rush mod or whole new ignition system? My springs are flat right now but I want my heep to run before I fix the ride quality.
Thanks for any help, these forums are great!

PoppaDucky is offline  
Sponsored Links
Advertisement
 
post #2 of 16 Old 02-01-2010, 11:03 AM
Ra8erFan
Registered User
1990 YJ Wrangler 
 
Join Date: Mar 2009
Location: Reno, NV
Posts: 78
I have a Weber 38/38 so I don't know if I can help you. On my carb the idle adjustment is in the throttle linkage at the back of the Carb, the screw head faces the left towards the battery. On my carb I have two mixture screws, I believe yours only will have one located at the base of the carb facing right. Team rush upgrade is cheeper to do [BUT] if I had the $ I would upgrade to an MSD ingnition system including a new distribitor. After the nutter by pass did you reset the timing?
Ra8erFan is offline  
post #3 of 16 Old 02-01-2010, 01:03 PM Thread Starter
PoppaDucky
Registered User
1997 ZJ 
 
Join Date: Jan 2010
Location: Telephone, Tx
Posts: 118
I did reset the timing, it's amazing what ten degrees will do to smooth out the engine. Last night when I was trying to adjust the idle though it seemed like no matter what I did to that screw it didn't change. Could that be caused by vacuum issues?
PoppaDucky is offline  
post #4 of 16 Old 02-02-2010, 01:21 PM
Ra8erFan
Registered User
1990 YJ Wrangler 
 
Join Date: Mar 2009
Location: Reno, NV
Posts: 78
I have the same problem sometimes. When I adjust the idle I also rev up the engine and then let it settle down. It seems like this can go on for a while until I get the RPMs where I want.
Ra8erFan is offline  
post #5 of 16 Old 02-02-2010, 02:04 PM Thread Starter
PoppaDucky
Registered User
1997 ZJ 
 
Join Date: Jan 2010
Location: Telephone, Tx
Posts: 118
Well I've been messing with it some more and I got the idle to go down to 1000 rpm but its still not right... I'm to the conclusion that it's not jetted right but I'm broke at the moment. Guess that's another thing to put on the "Jeep to do list"
PoppaDucky is offline  
post #6 of 16 Old 02-02-2010, 02:46 PM
wendell
Registered User
1987 YJ Wrangler 
 
Join Date: Aug 2006
Location: grafton ohio
Posts: 3,286
This maybe more than you had in mind, but this is what I did to my 87 258 to help performance. I installed a holley 470 TA 4 barrel, offy intake, comp cam, rollor rockers, 4.0 head, header, hei distributer, MSD, and 4:10 gears. Needless to say, it romps. I'm so impressed with it, I could care less about a stinlin V-8. It makes peak torque at around 1,800 rpm's, awesome on the trails, it boogies down the highway and light the tires. The holley TA 4 barrels are made for off road and will take extreme angles without flooding or fuel starvation. I've had a lot of jeep I-6's over the years, but this is the first one that I've built like this, truely impressive. The 258 in an awesome engine with it's lowend torque, any upgrade just makes it better.

1987 wrangler, 258 I-6, 5-speed.
2007 liberty sport 4X4, automatic
2009 ford ranger 4x4 FX4 OFF/ROAD, 5-speed
wendell is offline  
post #7 of 16 Old 02-02-2010, 03:52 PM
Lonan
Registered User
1990 YJ Wrangler 
 
Join Date: Oct 2009
Location: Tampa
Posts: 56
If you don't have a Fuel Pressure Regulator in line IMHO you're chasing your tail and will always run rich. You're pumping too much fuel. The stock Fuel Pump runs at about 8-9PSI. The max recommended fuel pressure for the 32/36 is 3.5PSI. I put a quality Holly FPR and guage in-line and run it at 3PSI and got rid of all the carb problems. Here's the one I got:
Holley 12-804 - Holley Fuel Pressure Regulators - Overview - SummitRacing.com
Lonan is offline  
post #8 of 16 Old 02-02-2010, 06:51 PM Thread Starter
PoppaDucky
Registered User
1997 ZJ 
 
Join Date: Jan 2010
Location: Telephone, Tx
Posts: 118
I'll check that when I get back home. I remember putting the regulator on but I can't remember what it's set at. If I remember right, the first carb was starving the engine so I had to set it way high, maybe at 5 or 5.5 psi.

Wendell, I'm jealous of your rig but I'm just a broke college kid. I have a 4.0 sitting in my shed that I'm hoping to turn into a stroker this summer so I'm holding off on using my head. For three hundred I got the motor, tranny and a rear end out of a 95. Best deal I've ever made.

I'll post up this evening after I check the pressure. Thanks!
PoppaDucky is offline  
post #9 of 16 Old 02-02-2010, 09:19 PM Thread Starter
PoppaDucky
Registered User
1997 ZJ 
 
Join Date: Jan 2010
Location: Telephone, Tx
Posts: 118
I stepped it down to 3.5 psi and it seems to have gotten better but it's too dark outside to try and tune the carb. I'm betting that I'll end up turning the psi down to 3 though.
PoppaDucky is offline  
post #10 of 16 Old 02-03-2010, 03:19 AM
wendell
Registered User
1987 YJ Wrangler 
 
Join Date: Aug 2006
Location: grafton ohio
Posts: 3,286
Good point Lonan, I also had to install a holley fuel regulator to get the carb to dial in properly. We were pulling our hair out before the regulator, it can make all the difference in the world.

1987 wrangler, 258 I-6, 5-speed.
2007 liberty sport 4X4, automatic
2009 ford ranger 4x4 FX4 OFF/ROAD, 5-speed
wendell is offline  
post #11 of 16 Old 02-03-2010, 09:58 AM
barry5
Registered User
1988 YJ Wrangler 
 
Join Date: Mar 2009
Location: Louisiana
Posts: 4
PD, I've got an '88 YJ w/ the 258. Did the weber 32/36 conversion, nutter, and msd box/coil. Below are some links to the data I used for carb install & adjustment. Mine's running great now. You need to ensure that you don't have any vac leaks or you'll just be wasting time trying to adjust carb. With regard to timing, mine is now set at 8deg. at 750rpm. Is yours set at 10deg at idle? I'm thinking of bumping mine up to see if it makes a difference. Anyone know the max base timing? Or do you just go up until you hit detonation?

If your still idling high make sure that your main cable and linkage is not holding keeping it high. If the carb idle screw is not touching the idle lever, then your linkage may be keeping the idle high.

Weber CARBURETOR SET UP AND LEAN BEST IDLE ADJUSTMENT

CARBURETOR SET UP AND LEAN BEST IDLE ADJUSTMENT

parts breakdown


Also, according to the research I did for the carb swap, make sure your dist. advance is hooked up to a ported vac. source (not manifold vac). Here's the JF thread I used: http://www.jeepforum.com/forum/f12/w...ite-up-382309/
barry5 is offline  
post #12 of 16 Old 02-07-2010, 08:55 PM Thread Starter
PoppaDucky
Registered User
1997 ZJ 
 
Join Date: Jan 2010
Location: Telephone, Tx
Posts: 118
Okay, I've been messing with it a lot since my last post and I'm pretty positive it's just a vacuum issue now. The psi is now set at 3 and it seems to run a lot better but it's still idling high and no matter what I do to the mixture screw it stays rich and I can't change the idle because the screw won't even touch the throttle if I disconnect all the linkage and throttle bracket.
So tomorrow I'm going to pick up all the stuff for the team rush mod and vacuum hoses and connectors. So here's the list I've made so far; please correct me if anything seems wrong:

Rush Mod:
plugs for a 95 yj (4.0 of course)
rotor, cap, & dizzy adapter for an 82 F150 I6
plugs while I'm at it

Vacuum stuff: (not sure about some of this and I plan on replacing the hoses since they're old)
line for ported vac, from CTO & dizzy to EGR port on carb, 2 T's for this
line for manifold vac, from PCV valve to ??? on carb and then to Charcoal canister, 1 T
No idea on the carb vent
I have a second PCV valve at the back of the valve cover? what about that?

Quote:
Also, according to the research I did for the carb swap, make sure your dist. advance is hooked up to a ported vac. source (not manifold vac). Here's the JF thread I used: Weber 32/36 Install Write-up
PoppaDucky is offline  
post #13 of 16 Old 02-08-2010, 02:29 PM
Lonan
Registered User
1990 YJ Wrangler 
 
Join Date: Oct 2009
Location: Tampa
Posts: 56
I don't think the answers to your questions are covered anywhere better than this 32/36 write up, as barry5 pointed out.
Check it out and all the details should be covered, including vacuum diagrams.

http://www.jeepforum.com/forum/f12/w...ite-up-382309/
Lonan is offline  
post #14 of 16 Old 02-08-2010, 06:14 PM Thread Starter
PoppaDucky
Registered User
1997 ZJ 
 
Join Date: Jan 2010
Location: Telephone, Tx
Posts: 118
The diagrams are what I'm having trouble understanding. I can't tell exactly where some of it goes.
PoppaDucky is offline  
post #15 of 16 Old 02-08-2010, 08:54 PM
Lonan
Registered User
1990 YJ Wrangler 
 
Join Date: Oct 2009
Location: Tampa
Posts: 56
That, unfortunately, seems to be the issue in most cases, including mine. The PO of my YJ left a bird's nest of lines with everything from golf tees as line caps to electrical tape melted on other lines. I'm no expert by any means. I followed the diagram for the major lines. Then I carefully traced each line and first made sure there were no vacuum leaks. As I found a leak I plugged it and noted it's effect on the engine and RPM. Then I got rid of the modified "Dead End" lines that went nowhere. These lines were shortened and combined in some cases. I'm still not sure it's correct but it runs quite well. I wish I could help more.
Lonan is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Jeep Forums Replies Last Post
Hawk Performance HPS High Performance Street Disc Brake Pads? NW Jeep TJ Wrangler Technical Forum 54 11-02-2011 09:54 PM
performance and not performance shocks MODUS TJ Wrangler Technical Forum 4 12-02-2007 10:53 AM
What is the one best add-on for performance for a TJ? jb1dsl TJ Wrangler Technical Forum 19 03-07-2006 05:16 PM
4.2 performance cv2004 YJ Wrangler Technical Forum 4 11-23-2003 04:20 AM
performance cam kauaijeep YJ Wrangler Technical Forum 2 11-21-2002 12:19 AM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome