jets jets..and more jets

[bohn333]

OK, i\'m on my 4th set of spark plugs, they foul out every 2 to 3 weeks, i called holley and they said to just keep rejetting it. Its like a hit and miss thing. I went to 71\'s already, i don\'t want to go to low and lean it out to much, what are you guys running for jets, perferrably they guys with the ZZ crate motors. Those seem to be the closest to mine in power out put. Thanks. http://www.s10v8.com/images/smilies/icon_wink.gif

[basementdweller]

What does the ZZ4 put out for HP? its a 350 correct? and what size cam are you running (lift / duration).. what size carb., vac. secondaries or mech. secondaries. Are you running a power valve? I can get ya REAL close if you can provide that info.

[bohn333]

A ZZ4 makes about 350HP, my cam is a Elgin 292duration 480 lift, 230 at .050. Holley 750 vac secondary, it says it has power valve blow out protection, so i\'m assuming it has one, what size i have no idea. My motor is not a ZZ4, but that is the closest one i think that is camparable to mine. I have all the specs listed on my profile, just click on my name for more motor info, thanks. http://www.s10v8.com/images/smilies/icon_wink.gif

[basementdweller]

Go 67\'s up front 69\'s in the rear (If you only have 1 metering block just go to 67\'s). See how that works out for ya. It may not be perfect but your plugs will last longer than 4 weeks http://www.s10v8.com/images/smilies/icon_razz.gif from there you can get a good idea after running it and looking at the plugs. Turn your air mixture screws all the way in and then back them out 1 1/2\" turns.

[basementdweller]

Dont forget to check your float levels.. you dont want to be dumping fuel!!! Take out the sight plug.. no gas should come out.. push down on the fender and get the truck to shake.. gas should dribble out.

[ZZ4Blazer]

I think that I had 68 or 70\'s in my motor with my 3310. Stock vacuum secondary spring.



How is your timing? Mine always ran really rich, and the guy that helped me install my motor in my old truck only had the initial timing set at 8. Factory is like 10 or 12, and I have it set around 14 now, and overall at 34 degrees. Runs much better. I could probably go up to 36, just haven\'t messed with it yet.

[bohn333]

Thanks guys, i\'ll try and see how it runs, my timing mark is off on the balancer, so i really have no clue where its at, i just advance it till it starts hard when hot the back it off till it smooths out.

[basementdweller]

make sure you find out what the power valve in there is (grab the number off it). If its opening too soon, it\'ll dump fuel and cause the motor to run rich. Power Valves are often over looked, and can cause major tuning problems if your not aware of what exactly they do.

[bohn333]

i put the 67 jets in it and adjusted the idle screws like you said, it has a hugh flat spot off of idle now. I pulled the power valve and it has several different numbers on it, theres a S then clockwise is 6 5 3, there real small so hard to tell. Any more suggestions, should i go up in jets or should i try something else?

[basementdweller]

What exactly do ya mean by flat spot. Does it hesitate, does it pop or backfire, or does it sound like it wants to turn off?

[bohn333]

it seems like it wants to quit as soon as you touch the gas, sometimes backfire through the carb. even at part throttle it will want to die when you give it gas, even if you ease in to it, it will still want to quit.

[basementdweller]

If its backfiring through the carb then your timing is off. I remember when i had my timing off, when i stepped on the gas the truck would almost turn off, soon as i took my foot off the gas the idle would go up and it would start running again. Make sure your distributor isnt a tooth off....bring it up to TDC on #1 compression stroke drop the distributor in and make sure the rotor is pointing at the #1 cylinder. Set the initial timing between 10-12 at first, then you can play with it. Are your headers red? Do they glow at all? That would be a sign of running too lean or incorrect timing.

[bohn333]

I\'m gonna go buy a new balancer then try to time it, how far should i advance it with my cam, i no longer have the cam card, so i\'m kinda guessing. 292 duration, 230 .050, 480 lift, installed straight up.

[ZZ4Blazer]

Advance the hell out of it. Advance it till it pings, then back if off. I\'d say atleast 32 degrees total w/ vaccum advance disconnected. I\'d say you could run up to 36 or so.

[bohn333]

i put on a new balancer today, so as soon as i can get a timing light i will time it. But i went to start it and the damn thing fouled all the plugs out again. I\'m thinking that my choke is what is making it foul out plugs. It has an electric one now. I\'m gonna take it off and see what happens. if that don\'t work then i\'m gonna go by a fuel injection set-up, because this is getting pretty sickening. I have bought so many spark plugs in the last 2 months that i should start buying stock in AC Delco. I don\'t even have to say anything when i go to AutoZone, they know what i want....lol.

[rudedogg]

gotta love that efi,harder to foul plugs,not impossible though.the efi set ups are getting better phttp://www.s10v8.com/images/smilies/smileJap.gifd chip mods to compensate for larger cam profiles and that instant fire up and drivability makes for an enjoyable cruzzzzz.what ever your preferrance may be lets go play http://www.s10v8.com/images/smilies/icon_biggrin.gif