BillZ260 Posted November 27, 2007 Share Posted November 27, 2007 Now that I have most of the exhaust on, and apparently solved the electrical issues, I'm ready to tune the 355 for the initial drive. I've been reading on reading and adjusting timing curves, how to properly adjust and tune the Eddy Carb, so here's my plan. If you have any input, it's much appretiated. Currently the motor won't idle lower than somewhere above 1500 RPM. I have a loose connection to find for the tach. Pull vacume advance and hook up vacume guage. Turn in both idle mixture screws all the way, then back out 2 full turns to ensure a bit rich enviroment. Start it up and set initial timing to about 12 Deg BTDC Adjust RPM's down to 850, if possible, if not check timing again (anything else here to get the idle down?) Let the motor come up to temp Re-check the above. Turn in ONE idle mixture screw untill vacume stops rising, adust in second to match the first. Adjust Idle back to 850 Re-check initial timing. Reinstall vacume advance (Initial adjustment? all the way in back out so much?) From here I can map the current timing curve, but i'm not really sure where to go after that. I understand how the mech and vacume advance's work, just not how to correlate how they change w/ my cam or whatever. I'd also like to check and adjust the AFR and make sure i have the right metering rods in the carb, but I guess i'll need to drive it to figure that out eh? Not sure I want to buy an AFM, is it a neccessary tool to have. If so can i stick the ox sensor in the x over pipe in my exhaust so it reads both banks? Thanks Guys. Quote Link to comment Share on other sites More sharing options...
jbk240z Posted November 28, 2007 Share Posted November 28, 2007 You might want to also check that you do not have any vaccum leaks. Check intake flange area, carb mounting, power brake system, etc. Good luck! Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted November 28, 2007 Author Share Posted November 28, 2007 Still a couple of electrical gremlins, but they are all my fault since I did all the wiring! Hope to get it sorted tonight while Crys is at class. Some coolant on the ground, coming from the back of the block, I HOPE that it's just loose heater fittings... Quote Link to comment Share on other sites More sharing options...
HICKL Posted November 28, 2007 Share Posted November 28, 2007 Are you working with a new carb or an older one that may have some crud or blockage. That may explain why you can't idle it down. I usually set my base timing right away before I bother with any carb tuning. Jeff Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted November 28, 2007 Author Share Posted November 28, 2007 Used carb, has a 30 min rebuild on it as of last year. If I can't get it down I'll pull it and check. Quote Link to comment Share on other sites More sharing options...
HICKL Posted November 28, 2007 Share Posted November 28, 2007 I have one of those carbs on a project truck I am building and mine is notorious for the idle circuit getting clogged if it sits for very long at all. Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted November 29, 2007 Author Share Posted November 29, 2007 I got the idle down to 850 w/ no problem, almost right away. I guess w/ no mufflers it sound like it's running faster than it is? Checked the timing, I think it was about 15 Deg ATDC at idle! I really need to have another person helping me, trying to watch the tach, vacume guage, timing light and keeping the engine running was really difficult! The thing got to temp really quick and with the timing so advanced, the headers and about 2 foot of the exhaust was glowing red by the time I got the timing set to 12 Deg BTDC and the idle adjusted. The Headers cooled off pretty quick but the exhaust tubes stayed red for a while. I turned in the Idle adjustment screws but the vacume did not move off of 10 in/Hg after two 1/4 turn adustments. I checked my other guages, oil pressure was down to about 45 psi and temps were climbing. Reved it up a bit and it started to cool but the floors were HOT so I called it a night. As soon as I turned off the car, I think I found my coolant leak The thing was puking all over the place, I need to get a catch can! I think the initial timing is set now, I need to clean up the garage and get some help and finish the tune up. Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted November 29, 2007 Author Share Posted November 29, 2007 Found another method using an adjustable timing gun (which i have), I'll check my settings and see how they compare. Downloaded the Eddy Carb Owners Manual, lots of good detailed tuning information there. I'll keep you posted... Quote Link to comment Share on other sites More sharing options...
pparaska Posted November 30, 2007 Share Posted November 30, 2007 Bill, with the ignition timing retarded to 15 deg AFTER TDC, there's no wonder the exhaust headers were hot and the thing was puking coolant out of the overflow - retarded timing will cause lots of heat. Did it get a chance to run long enough after changing it to 12 BTDC to cool it down? Good Luck! Pete Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted November 30, 2007 Author Share Posted November 30, 2007 Well Pete...It was acutally 15 BTDC BEFORE I started jacking with it. So I happily adjusted it to 12 Deg ATDC, I guess I was looking at it backwards... How's your back by the way? I realized this about mid-day yesterday, sitting at my desk trying to figure out why it was so hot, and it hit me that I was looking at the wrong side of marks on the ballancer. I guess I can add this to the "stupid moves" post. SO last night, I re-set the timing over to the other side of the mark at about 12 Deg BTDC and it imeediatly ran much better. THen I tried the 2nd method that I read about, which is turn the dial on your gun to 36 Deg, start the car, rev to 2500-3000 and ZERO the timing marks. Runs almost perfect. Revved and Idled for at least 30 minutes, no over heating issues at all, fan was on/off coolant never over 200 sitting there in the garage. Idles easily at 700 rpm, and doesn't keep running when I turn off the key Lots of throttle responce but with the vacume advance hooked back up it was backfiring on the way back down. Still running rich, need to finish the tune and get her leaned out a bit. I absolutly hate the garage smelling like fuel. Was able to move her back and forth a bit under her own power in the drive, cluch needs another 1/16" of movment to totally dis-enguage( I hope ). Couldn't get it in gear running, but could kill the motor, put it in gear and start it up w/ no issues. Oh, and I found out I forgot to put the Trans Breather tube back in after I rebuild the tranny, it's sitting on my bench, and now I'm getting a small puddle of trans fludid from it I think. Any ideas on getting it in w/ out pulling the powertrain? Also a small puddle of oil, hopefully the pan that needs to be repalced anyway. The small things just kill! But I'm getting so close!!! Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted December 3, 2007 Author Share Posted December 3, 2007 Ran out of gas yesterday trying to finish tuning the carb So I spent the afternoon getting the guages all hooked up and working, as well as a couple of accessory switches here and there. Found access to the breather vent on the tranny, doesn't look like it's the leaky culpret Any other thoughts? I'll check the fill / drain plugs, but other than, that since the drip was in the center of the trans not behind the engine, not sure what it could be. One day at a time... Once more progress is made I'll start another tread detailing my progress, and once I have a final "TUNE" set up I'll post the results here.... Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted December 5, 2007 Author Share Posted December 5, 2007 Got about 3 gallons in her last night, finished up the idle and idle mixture. Idles and revs much better after the adjustment detailed in the EDDY manual. Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted January 3, 2008 Author Share Posted January 3, 2008 Any quick thoughts as to why it starts to run very irradic when above 3300 rpm or so? Should I just pull the vacume advance all together? 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.