2005 502 Questions

[gaston 2005 502]

A few questions, first the easier.

1. what is the proper torque for valve cover gaskets? some will say good an tight,,, but i would like to have a proper value whether ft lbs. or inch pounds.

2 chrome was peeling in three locations on my valve covers and i sent them back for warranty and were replaced immediately Rodger Mcclain at Lima Auto Mall AND the Factory gave perfect assistance. Requested new valve cover gaskets and pvc grommets and the replacement valve covers and got them. However,the covers i sent off had hold down tabs formed into the cover itself,,, which i liked. The new set does not. As stated the bike is 2005, does anyone's 2005, 2006 or 2007 502 have these type valve covers with NO hold down tabs molded into the metal of the cover? Is this a cheaper version? or is it an outdated version? or what?

3, now of performance, 5700 miles now, got it when it had 2700 miles, installed the vacuum advance and set timing on 36 degrees with i think it was six turns on the vacuum adjustment allen screw. I performed carb mike's stage two mods with the only omission being being to trim the gasket inside of the accelerator pump hole. Now my issue, most of the time when i whack it from say 40 or 60 mph i will get a good clean crisp whack. Plugs i changed and all the same and they looked good to my comparison of plug reading chart. But once in a while,, when i whack it between those speeds,,, i get a stumble. changed distributor cap and rotor, have gone back to the original plug wires as i was getting a miss out of my $160 ones, was using the borg warner select with brass inserts dist. cap. this time went to a MSD dist cap with brass inserts. Now i have recently read in the manual "
ADDITIONAL TIMING SETTINGS: (WITH VACUUM ADVANCE CONNECTED)
502 engine: TDC at 42 degree at 2400 rpm"

have yellow and silver springs in the dist. when it runs good,,, it runs great,,, but occasionally it stumbles. I whacked it 3 times yesterday,,, no stumble, but the fourth,, got a stumble. I check the dist. cap about once a month for corrosion on the brass tabs and have a little corrosion on the tabs when i check it. Not much, but a little and i replace it. I know i can clean the corrosion,,, but i change it. that tells me arcing during fire and firing when not completely lined up during rotation of rotor to cap and or timing adjustment needed? Cold weather (like we really get it here in south texas) i though it runs better,,, but the weather does NOT seem to make a difference. Runs good and stumbles occasionally in warm or cool weather. Also have a MSD electronic module with rev limiter installed and rev limit set at 5700 rpm. Idles good,,, normal performance good,,,, just an OCCASSIONAL stumble. 100 miles, 5.6 gallons,,, 17.8 MPG plus another 60 miles later so vacuum advance install has helped my mileage. Also installed the quick disconnects for the gas lines from small parts.com. One other tidbit, when going to whack it, my normal method is take off normally accelerating till about 50 mph, speed limit goes 35, 4o, 45, then 5o for about 1/4 to 1/2 mile, then whack it up to 100 and let off. Any help on this issue or experiences will be appreciated.


Darryl

[AR]

i aint got a 502....maybe wingman can help ya.

[502wingman]

Sorry, but I am not familiar with timing etc. All I can say is that Andy (Boss Hoss Cologne) installed my vacuumadvance and its been working great since then. I had a bit of a stumble (time lag) when I whacked it. Then Rick at Summit BH took off the vaccum for the secondaries of my quadrajet carb. Now the secondaries kick in immedeatly as soon as I open the throttle a bit faster than usual = great. So this is a more mechanical solution, but it works perfect in my case. The sensitivity of the secondaries may also be adjusted with the springtension.
Peter

[gaston 2005 502]

Peter,

I appreciate your reply and I will adjust my secondary spring tension as i set it at 1&1/2 turns and it "feels" to much as i have a harder time opening the secondaries.

Also What do you mean "Rick took off the vacuum of the secondaries,,," did he reduce the amount needed to open as per carb mike's details?


Also I went to Chevrolet dealership and asked the required torque on valve covers and stated a 454 chevy pickup and correct value is
71 inch pounds and i would think this is comparable. now to my other issues.

Darryl

[502wingman]

Darryl,

there is a vacuum can on the right side of the quadrajet. This setup regulates the secondaries i.e. it also delays the kickin of the secondaries. I guess it is kind of a safety feature. Rick from Summit (who told me that he has spend 3 month in Rochester for these carbs and is, by the way, also a specialist for NOS), said that you dont need that and it is only there "for causing trouble". So he took the whole thing off. So now the secondaries just flip open when I give enough throttle and "bang you go"

Peter

[gaston 2005 502]

Peter,

Thanks for the info as i will give it a try when i get back from work, going to China tomorrow till the 21st

Darryl

[AR]

Peter,

Thanks for the info as i will give it a try when i get back from work, going to China tomorrow till the 21st

Darryl

They got V8Bikers in China?

[gaston 2005 502]

Goverment probably wouldn't let em in.. and if they did most all couldn't afford them on $125 per mont average salary. They do in Japan,,, but it was dark there last night when i went through so i didn't get to see any no less at the airport

Darryl

[gaston 2005 502]

Carburetor Mike,

Have you ever had any experience of as Peter speaks of as removing the vacuum can on the side of the carb?

"

Darryl,

there is a vacuum can on the right side of the quadrajet. This setup regulates the secondaries i.e. it also delays the kickin of the secondaries. I guess it is kind of a safety feature. Rick from Summit (who told me that he has spend 3 month in Rochester for these carbs and is, by the way, also a specialist for NOS), said that you dont need that and it is only there "for causing trouble". So he took the whole thing off. So now the secondaries just flip open when I give enough throttle and "bang you go"

Peter

Any experiences regarding this will be appreciated

Darryl

[zenbiker]

Peter...I can't believe you are saying there should be no modulation for the opening of the secondaries. If you remove the system, the secondaries will kick in whenever vacuum drops...like giving it more throttle on a hill or whatever! Not for me! ...Joe

[Tom]

Remember the bottom butterflies are mechanical. There is no way the air valves can open with the butterflies closed because there is no venturi opening pulling vacuum under them and there is spring tension holding them closed.. The vacuum pot controls the speed at which the air valves open to increase the vacuum in the main body to pull fuel to act as an accelerator pump for the secondaries. Without it you will have to adjust the opening with the spring tension only. I have never tried it but am interested in what Mike has to say.

[gaston 2005 502]

Tom,

Your reply and explanation is appreciated,,,

CArburetor Mike,

What are your thoughts of the removal of the vacuum can for the secondaries as suggested earlier in this thread?
Advice and knowledge appreciated,



Darryl

[502wingman]

Joe, as Tom says it does not kick in that easy. I really have to turn the throttle fast to open them. It is easy to control, but it kicks in faster by will.
Peter

[Bryan]

Hey Gents,

I guess I'm living proof that I'm not the sharpest knife in the drawer some days, because I did just what you're talking about.

When I installed a manual choke on my carb I assumed the vacuum pot controlled the automatic choke action, so I took the pot off and threw it out. I didn't realize the pot controlled the speed at which the butterflies open. So of course once I wacked the throttle I had the big bog because they opened too quickly. So we messed with the windup spring and got it so the opening speed was right and thus the end of the bog. The secondaries open every time whether I wack it hard or just roll into it so it works well. We just had to wind the spring up tighter than normal, that's all.

Bryan

[gaston 2005 502]

Bryan,,

Thanks for the first hand installation knowledge. I slightly damaged my vacuum pot and ordered a new one before i made this trip to work. I ordered from the following site and they have alot at what i found to be reasonable prices.
http://www.carburetion.com/

Do you have any idea how many turns you had to put on the windup spring?
Thanks for the reply also.

[Bryan]

Daryl,

It was a long time ago but I seem to recall about 1 1/4 turns from the time the load come on to the spring. However I think this will vary from one carb to the next.

Bryan

[gaston 2005 502]

Thanks Bryan and all for the information. I have mine set now at about 7/8 turn. i am going to try first putting the vacuum canister back on and see if my "issue" is fixed. If it is not i will remove it and try the spring at 1&1/4 turns. Thanks again,,,

[KrautV8]

Thanks Bryan and all for the information. I have mine set now at about 7/8 turn. i am going to try first putting the vacuum canister back on and see if my "issue" is fixed. If it is not i will remove it and try the spring at 1&1/4 turns. Thanks again,,,

Darryl,
don't adjust too much at a time. You want to have the tension AS LOW as possible, without the engine bogging when you hit the throttle.

Not enough spring tension = secondary air flap opens too fast = big bog
Too much spring tension = secondary air flap opens too late = slow bike

Start with 1/2 turn spring tension, and make a test ride. If it bogs, adjust in 1/8 steps until it stops bogging. My SB with 1901 carb needed 1 1/8 or so if I remember right...but that doesn't mean much to your carb and bike.

Before you adjust something at all, make sure that:
- fuel pressure is somewhere between 4-7 psi,
- the accelerator pump works like it should
- the small filter inside the carb, any inline filter, AND the filter at the petcock is clean.

Olaf

[gaston 2005 502]

Olaf,

thanks for the reply. it just so happen i am going into it tomorrow as i plan on checking my float level and rejetting the primaries. i think i will also try and reduce spring tension. if i remember i am at 1 full turn now. will let you know how it comes out

Darryl