I messed some more with my carb and dizzy....

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TT, I heard that it was a Edel carb, but for a time there Edel had Qjets going also, I forget wether Carter or how, but Edel DID supply Qjets also....
been some years now, I went FI long time ago, and never looked back...

:surrender:
 
Yes, but the Edelbrock Q jet replacement carbs is nothing like the Carter AFB type that Karsten has.
 
Twin_Turbo said:
Yes, but the Edelbrock Q jet replacement carbs is nothing like the Carter AFB type that Karsten has.
Click to expand...

Yeh, obviously, I kept thinking Qjet as i'ts much more common, and matches they symptoms he is having.....I never had a AFB do that to me, or anyone else for that matter....best damn 4bbl on the market, EVER....
when in doubt, use two of them....cooler than any tripower even...

:devil::devil:
 
MYBAD79 said:
Carb adjustments seem to have little effect, I moved the pump rod one more hole and it's somewhat acceptable but it still stutters at low rpm acceleration....

I installed the AR12 vacuum can and the golden springs from the MRG 928 kit.

Timing is at roughly 12 degrees advanced at idle (with vacuum connected) and at roughly 36degrees advanced at 3000 rpm.... that's just eyeballing the dampener marks... 45 degrees is easy to spot, my advance is a lot less....

This vacuum can really pulls less advance than the old one... now my ignition is set and I have to tinker a little more with the carb... maybe go to .110" jets (that's between the stock .113 and currently installed .107).....

oh boy this is fun......
Click to expand...


I would add more initial timing (vacuum advance disconnected) to about 18* at idle. If you need to limit the total advance (initial and centrifugal) to 36*, do it with a limit bushing. Some engines, especially "cammed-up" ones need more initial timing than the factory specs. dictate.
 
big_G said:
MYBAD79 said:
Carb adjustments seem to have little effect, I moved the pump rod one more hole and it's somewhat acceptable but it still stutters at low rpm acceleration....

I installed the AR12 vacuum can and the golden springs from the MRG 928 kit.

Timing is at roughly 12 degrees advanced at idle (with vacuum connected) and at roughly 36degrees advanced at 3000 rpm.... that's just eyeballing the dampener marks... 45 degrees is easy to spot, my advance is a lot less....

This vacuum can really pulls less advance than the old one... now my ignition is set and I have to tinker a little more with the carb... maybe go to .110" jets (that's between the stock .113 and currently installed .107).....

oh boy this is fun......
Click to expand...


I would add more initial timing (vacuum advance disconnected) to about 18* at idle. If you need to limit the total advance (initial and centrifugal) to 36*, do it with a limit bushing. Some engines, especially "cammed-up" ones need more initial timing than the factory specs. dictate.
Click to expand...

I don't recall the exact cams in which engine over the years, but it seems that man time for me, when using lots of initial, the starting was a super bitch when hot, and it IS Florida.....had a Qjet '75 van once, it had the 'problem' but not the vehicle suffering the most....so trick was to lower initial and take out the bushing under the mech advance....

:confused2:
 
Update: I removed the .107 primary jets and installed .110 primaries (stock is .113 but that was too rich)
It's better but not perfect (yet)

Still stuttering a little when accelerating from 2000-2500 rpm....

I already installed the stiffest springs for the metering rods.

Tomorrow I'll try different rods, currently the stock rod is installed.

more fun.....
 
Update: now it runs without stuttering and hesitating.

I installed the stock jet sizes that the Edelbrock tech-guy sent me. The jets that I had in there were bigger, no idea why... maybe I got somebody's return...

Anyways.... stock jets: primary .113 and secondary .107, stiffest springs for the metering rods. works fine, drove about 12 miles today and it seems to make pretty good power all the way up to 6500.

I'll have to fab some mufflers for the sidepipes, the maxflows are a little loud above 3000rpm :oh:

The timing is set to 10 degrees initial without vacuum, it did run a lot better with 14 initial but it seems to start easier with less advance... maybe my imagination.... I'll try more advance some time this week.

Limit bushing.... I found some info from MSD:
setyourtiming.com/pdf/8365_frm28975.pdf
 
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MYBAD79 said:
it did run a lot better with 14 initial but it seems to start easier with less advance... maybe my imagination.... I'll try more advance some time this week.
Click to expand...

8982_full.jpg
 
Twin_Turbo said:
MYBAD79 said:
it did run a lot better with 14 initial but it seems to start easier with less advance... maybe my imagination.... I'll try more advance some time this week.
Click to expand...

8982_full.jpg
Click to expand...

TT/Lars....here we go for a question now, I have read here/over years to just ignore the initial advance and set dizzy for 36-38 whatever at 3 grand, but then over the years I have pretty consistently found hot start issues in summer especially with anything over 10-12* initial, and even in winter, hot start crank fighting starter at 14*.....

so the obvious...why not take out the dizzy advance limit bushings, set initial at 10 where it seems most happy and tune advance for 38 and have done with it???

:surrender:
 
Looked for that little red box at Summit. Their product description says:
"They must be used with an MSD 6, SCI, 7, 8, or 10 ignition control."

The 6AL box seems to be very popular. Who's running one and is it worth the money ? Did you notice an improvement ? The rev limiter sure is a good thing to have.
 
Either get the new digital model or get a mallory hyfire box (I liked cranes box the best, have a fireball hi-6 w/ boost retard and a bunch of bells & whistles...but since they went belly up.....)

The MSD 6 series analog ones are the crappiest of them all.
 
There is a hei factory module with an extra wire than can be switched to retard the spark about 10° just for starting. Was originally designed for emission control.

Will have to look up the part #.
 
I looked at Summit's website... mallory Hyfire box, $200... same price as the MSD box and it has the rev limiter.
Will I notice a difference/improvement with the multiple spark or is it just a nice looking underhood 'bling' for $200 ??
 
The only real reason to run one of those boxes is if you want to use a magnetic breakerless type ignition that can't fire a coil because it has no amplifier, then you need the box to do that. Well..maybe it's a nice expensive but better looking replacement for one of those ugly ballast resistors (you won't need one w/ a box)
 
I saw those distributors, they're not as tall and look a lot cleaner.

Distributor: $250-$300
Hyfire box $200
Start-retard control box $200

$700..... for that much money it better be worth 20HP .... I think for now I'm happy my China distributor that I got for $80 (think it's Procomp).... :chinese:
 
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mrvette said:
big_G said:
If your ignition was working properly before, you won't notice a change in performance.
Click to expand...

UNless you have a rich idle carb setup...smooths out greatly then.....

otherwise, NO....

:D
Click to expand...

There ya go. NASCAR runs them for THIS reasone, and this reason ONLY. They also run TWO on an A-B setup, because the POS fails with regularity in 500 miles.
They help keep the plugs from loading up with the super rich idle.
 
big2bird said:
mrvette said:
big_G said:
If your ignition was working properly before, you won't notice a change in performance.
Click to expand...

UNless you have a rich idle carb setup...smooths out greatly then.....

otherwise, NO....

:D
Click to expand...

There ya go. NASCAR runs them for THIS reasone, and this reason ONLY. They also run TWO on an A-B setup, because the POS fails with regularity in 500 miles.
They help keep the plugs from loading up with the super rich idle.
Click to expand...


Serious?? jeez.....:gurney::evil:
 
010752 said:
There is a hei factory module with an extra wire than can be switched to retard the spark about 10° just for starting. Was originally designed for emission control.

Will have to look up the part #.
Click to expand...

You can stay with the reliable hei module.
This is the Hei 5 pin module.
Can replace the oem 4 pin.
Has the extra R term than when grounded with a switch will retard the spark 10°, good for hard starting advanced timing.
Extra term was originally for a knock sensor.

Standard Products LX330, can cross to AC Delco or others.

Less than 25 bucks wholesale or around 60 bucks retail.

StandardLX330.jpg
 
That's it. It should be a good price, not much call for them these days. Good price to test.

Here is the AC Delco equivalent D1941.
http://cgi.ebay.com/ebaymotors/D194...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

The oem Delco are supposed to have the proper dwell properties and apparantly the aftermarket performance modules don't adjust dwell thru the rpm range as GM did and give just the proper dwell for higher rpm. Don't know if Standard is a direct GM copy or not, never had problems with their parts.

Perhaps someone knows the difference, I don't.
 
010752 said:
That's it. It should be a good price, not much call for them these days. Good price to test.

Here is the AC Delco equivalent D1941.
http://cgi.ebay.com/ebaymotors/D194...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

The oem Delco are supposed to have the proper dwell properties and apparantly the aftermarket performance modules don't adjust dwell thru the rpm range as GM did and give just the proper dwell for higher rpm. Don't know if Standard is a direct GM copy or not, never had problems with their parts.

Perhaps someone knows the difference, I don't.
Click to expand...

I may have some of them at home, but I'm outa town. Less than $20 is cheap though. Check at Rock Auto.
 
Karsten, did you try messing with the pump shot volume? Did you try a smaller set of squirters to make the pump shot duration longer? How much manifold vacuum do you have? If it's low, you need a set of softer step up springs so your metering rods actually pull down to the economy step, yours may be not pulling down giving a rich cruise/low rpm because it's running on the enrichment step all the time. If your car idles and cruises lets say around 11-9" Hg of vacuum you will need a 9" or thereabouts spring so you can cruyise lean and have the enrichment when you need it. You may very well have either a gap in your fuel delivery or it's running pig rich down low causing a stumble as the engine recovers from the rich condition.
 
I installed the stiffest springs in the kit per Edelbrock's manual (page8). Right now it's running almost perfect, spark plugs are light brown (tan) indicating it's running slightly lean.
I'll try #7 on the chart in the manual: 1 step richer in cruise and power mode: easy change, it's just a rod...

Pump shot... I moved the rod up to the upper hole and it runs ok, moved the rod to the center hole and the stuttering gets worse.
I drilled another hole where the "X" is and moved the rod to that new hole... that did not make a noticeable change.... I am expecting some improvement from the next rod change....

the photo below is the old 600cfm carb, was easier to use that one for the photo...

214a5153c343bb0.jpg
 
Try some smaller nozzles to time the pump shot longer, no sense in upping the shot if the fuel is consumed too quickly, you need it to last to cover the dead spot between dile and off idle transition to main booster metering, that's the dead spot you are trying to cover. Slow on the throttle and the transition circuit handles it, nail it and it's a pump shot deal.
 
I installed different metering rods (2 stages richer in power and cruise mode, #11 on the chart) - of course I did that before reading your reply here....LOL.... anyways, I only got to take it out for 2 minutes before it started to pour.... but I think the dead spot is gone... I'll have to do some more testing tomorrow if it doesn't rain...

If I need smaller nozzles, where do I get these and why are they not part of the $60 calibration kit ?? All I got for $60 is a few jets, springs and rods.... they sure know how to make money.... :cussing:

Here's the chart and the rod info: Im at #11 now and it seems to run better.

214a54b26937da4.jpg
.
214a54b269ad056.jpg
.
 
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