Guest Anonymous Posted December 6, 2001 Share Posted December 6, 2001 Well good news, the z is running again, bad news is She is running really really hot, and the middle two exhaust headers are glowing. Now I remember that people said, I thought, you were too far advanced then you would run hot. Don't quite remember what they have said. I'm running the victor jr intake as well as the edelebrock carb. 600cfm which I'm told will supply enough fuel for up to 400+hp, and I"m just under 400 now. I know I set the timing to 17-18 @ 750. Now what i was wondering is that it still seems like she is running really fast. I mean I feel that with the cam I have in there, (Comp Magnum 270 270degrees advertised duration, 218duration @ .050) I"m supposed to get a nice little lobe, not getting that. I was then playing with the carb a little bit. What I"m wondering is do I need to turn the idle set screw all the way off, and then adjust the timing till it starts, or what would you guys recomend. I really don't want to take it to the shop, since they won't teach me anything there. I know I can get it to run properly, I have all the tools. I just need the info now. It doesn't back fire any more, so I think I fixed that problem. I set the idle mixture screws down some. I did notice that when I drove it around the block, she seemed pretty sluggish, not responsive at all like I have had her before. Also the victor jr intake whould give me more of a power range correct? I was wondering, do I need to slow the timing down, then increase the idle screw. Just wondering. Any input anyone has is greatly appreciated. Is there any good books on how to time/tune your 350? Quote Link to comment Share on other sites More sharing options...
patzky1 Posted December 6, 2001 Share Posted December 6, 2001 Since I, myself, am no expert with carbs so I'll just say something that might be obvious: You set the timing right and also turned down the idle mixture. Is it possible that your car is just running lean but somehow is also running fast? The lean running, to me, would explain why it is running hot and sluggish but not why its running fast at idle. Maybe that is just a throttle problem?? I hope this helps, if only a little bit. Pat Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 6, 2001 Share Posted December 6, 2001 Have you tested for vacuum leaks? The idle circuits often don't want to work if a bunch of air is leaking in somewhere else. A logical place would be in those two cylinders that are glowing hot.. Disconnect the vacuum advance and set your initial timing, tune the idle adjustments for maximum vacuum using a vacuum gauge. I suspect you'll find a vacuum leak though. You can cup your hands lightly over the carb inlet, if it picks up RPM's its got a leak, if it wants to die, things are ok leak wise, at least its not a large leak. Just a few ideas, Lone Ps: Is that 17-18 deg initial advance without a Vacuum advance attached? Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 6, 2001 Share Posted December 6, 2001 yes it is with the vaccum advance unhooked sean Quote Link to comment Share on other sites More sharing options...
Guest kc6wfs Posted December 6, 2001 Share Posted December 6, 2001 Seems like a intake leak to me also. But did you use a smaller dia. dampner? If so the timing marks are going to be off. I got bit by that! If so and running a SBC pull #1 plug and find TDC and see where your mark is. But also I would think all tubes would be glowing. As far as the carbs screw them in all the way and back them out 1 1/2 turns for a ruf adjustment. After setting timing or finding intake leaks it will change. What carb are you running? I'm used to Holleys. As far as idle adjustment it should not be screwed in much. Mine will idle very low with the idle adjustment backed all the way off. Be sure you have something like 1/32 opening from the butterflies with the idle adjustment backed off. Hope this helps. Keep us posted.. Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted December 6, 2001 Share Posted December 6, 2001 mostly good advice above! sounds lean like an air leak to me too. btw remember that intake can be sucking air fron a leaking gasket on an intake port from the lifter gallery area too, so just because the top side does not suck air does not prove its not sucking air fron the lifter gallery area!also that carb should have the idle bleed needles turned in till they just touch then backed out from about 1.5-->2.5 full turns if your much off this area something else is wrong(ignition timeing,valve adjustments, air leaks,wrong jetting,wrong metering rods or the metering rods are stuck) Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 6, 2001 Share Posted December 6, 2001 I now have a vaccuum gauge and a good rpm gauge that measures in 20 increments. I"m gonna go test to see if I have a vaccuum leak via the way lonerider said. If I don't I'm gonna play with the timing and vaccuum theories the way everyone on this site and on chevy talk has told me about. Thanks for all the info and if you have more info, please let me know. Lonehdrider on the vaccuum question I Have just been unhooking the dist. Should I be unhooking the line going to the mast vaccum, ie the line on the back of the carb as well? again thanks for everything everyone. sean Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 6, 2001 Share Posted December 6, 2001 OK, Here is where I"m at now. I turned the idle set screw 3 turns. 1 turn opened the butterflies about a 32th of an inch. It is now idling at 550. When I pulled the line on the master vac the rpm's picked up drastically to 750. When I put my finger over the line it slowed down considerbly to 575. when I just allowed a little opening it picked up just a touch to 600. So I have a vaccuum leak since it didn't want to die, correct? Thanks for the info. sean Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 7, 2001 Share Posted December 7, 2001 If your disconnnecting the vacuum line to your vacuum advance diaphram thats all that necessary to set your initial timing. Just to make sure I conveyed this right, leave all your hoses connected and lightly cup your hands over the top of the carb (air cleaner off obviously). If it picks up RPM's then its probably got a vacuum leak. If it wants to die, it doesn't or at least not a significant one. This works because your richening the mixture by restricting air flow. I'm sort of wondering if this is the case for you though, as when you introduce more air (unblocked hose) it picks up RPM's. Also your RPM seems pretty stable to be a vacuum leak as they usually don't like to idle or idle pretty roughly with a vacuum leak. If it had a vacuum leak like I early suspected it probably should have gotten worse when you opened up the hose and not better. Another way to check is by spraying like chemtool (or any other flamable aersol solvent) along anywhere you suspect a gasket leaking, when you find the spot the RPM's will come right up temporarily as its sucking in the extra fuel (solvent) where it was leaking. Outside of that and timing, I'm not sure what else to suggest. Anyone else see anything I'm missing, or that I mistated? Regards, Lone Quote Link to comment Share on other sites More sharing options...
Guest needwaymorespeed Posted December 7, 2001 Share Posted December 7, 2001 If you pulled a vac. line off and the rpm went up at idle youre carb idle mixture is too rich-you introduced umetered air into the engine-effectively leaning it out and the rpm increased- Id look at that carb real close the idle mixture is off running too rich at idle -and it souds like it's too lean in cruise or power mode thus the cherry red headers Tru installing smaller metering needles in youre carb-way easy only two screws-If problems still there try going to bigger jets-scre youre idle mixture screws in for the idle increase. Id also bump youre timing up just for kicks as posted earlier youre tdc mark on the balancer might be off to true tdc-could always put a piston stop in and find out true tds Good luck Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 7, 2001 Share Posted December 7, 2001 Ok no vaccuum leak. When I cupped my hands over the top of the carb, it tried to die, so that's good. Now I'm gonna play with some of the other ideas you guys have given me. Should I torque the bolts down to 28? they are at 25 now. sean Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 7, 2001 Share Posted December 7, 2001 ok the two front screws on my edlebrock are the metering screws, correct? Well, how percise are they, I mean I can turn them all the way out or in and they really don't make any difference in the idle at all. Maybe 50 rpm's, if that. it's actually more like 20-30. Does this mean that they are bad? and should I fix that. The car is still backfiring when i turn it off, or when I give it some gas. sean Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 7, 2001 Share Posted December 7, 2001 where do I get a piston stop? no auto place here has heard of them sean Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted December 8, 2001 Share Posted December 8, 2001 http://www.jegs.com/ part#249-4795 PISTON STOP $14.00 or 778-66792 TDC Locator $ 9.99 Quote Link to comment Share on other sites More sharing options...
Modern Motorsports Ltd Posted December 8, 2001 Share Posted December 8, 2001 "ok the two front screws on my edlebrock are the metering screws, correct" Sean, you've got the manual right? It does a good job of describing the process as we've been talking offlist for a while. Those two screws control only your idle mixture/circuit. If turning either one in all the way (don't push them in too hard at bottom) does not significantly affect idle (ie. stall it out or close to it) then you have 'numb' idle screws or fuel is getting in thru the other port, peak into your secondary port and primary to see if it's dripping in their (might have to hold secondary weights open to see down, I recall doing this, I had a numb idle screw once and just exchanged it, PITA to find out but I still love those carbs). A TDC piston tool I'd have a hard time justifying myself. If really in doubt remove valve cover, and #1 spark plug (or all plugs to make turning easier, your choice) and put finger on #1, you'll easily feel compression stroke as it comes to TDC #1 compression and rocker geometry relative to each other intake/exhaust will verify TDC ballpark to know if timing tab or rotor is out etc. I know it's been quite frustrating for you, are you sure you only have 5psi pressure or so at the carb? I setup a psi guage and regulator right in my engine bay right above OEM fuel filter just to know idle pressure was good. You may have too much psi and flooding or floats are high or....their manual is pretty complete. Hope it starts working out soon. You can check plugs from an idle and know if it's excessively rich or lean. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 8, 2001 Share Posted December 8, 2001 Well everyone, I found the problem. The timing mark is 60 degrees off. I went and got a piston stop, and set it in there. It stopped when the tape was reading around 60. Now I'm off to buy a new spark plug, and then to try and start her up and see how she runs now. I bet she purrs like a kitten. Will keep everyone posted. Sean Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 8, 2001 Share Posted December 8, 2001 well set her all up and she fired first shot. Oh she sounds so healthy. tuned her at 14 @ 700. played with the idle adjustments and now I"m gonna take her for a spin. will let everyone know how it goes. sean Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 8, 2001 Share Posted December 8, 2001 well she was kinda sluggish at first. I brought her back home and kicked up the timing to 17 and she is running A LOT better. Thanks everyone for helping me with this problem. Now I just have to tweak it all and she will be running superb. Once again, thanks to everyone. Sean Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 8, 2001 Share Posted December 8, 2001 Glad to hear it man, wish we could have gotten it sussed quicker, but I'm glad to hear it was something relatively simple. Now for the fun part, to enjoy! Regards, Lone Quote Link to comment Share on other sites More sharing options...
DavyZ Posted December 9, 2001 Share Posted December 9, 2001 Enjoy your car, Ellobo! Glad to hear the 'problem' is now fixed! Thanks for keeping us posted, BTW. Davy Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.