just found out from the builder the cam is advanced 4 deg what does this mean?advanced at the timing chain
this is if my memory is working right, but a cam that is installed advanced or retarded is in relation to the crankshaft. meaning that four degrees advanced is opening and closing valves alot earlier in the crank rotation. yes this might throw your timing off due to the change in when everything is opening and closing
I don't have much to add to this, you have some really knowledgeable guys helping ya out here. First, I have seen this missed soo many times, if you look at the baseplate under the metering blocks there are 2 (usually)open vacuum fittings(one rear sometimes one front). just pipe threaded holes really. because you have to basically turn the carb upside down to see them alot of people miss putting those plugs in there. Other option is it could just have slip on ******s sticking out of there, but be warned, a lot of the holley baseplates don't have anything in there, just threaded holes. Make sure and check the front and the back. The way its dying when you put it in gear sure sounds like a damn vacuum leak to me. bring it up to a high idle (2500 rpm) and hold it there for about 2 minutes after it has warmed up. Heres the important part. Shut the key off WITHOUT letting off the throttle. If it deisels, put it in gear to kill it. This will give you a true part throttle read on your jets. Just pull a couple plugs and look at the color. If you lift off the throttle before you shut it down, you wil be getting a reading off of just whatever your mixture screws are set at. Here is a quickie guide for you: White = lean Beige/light brown = sweet spot, very close Black = rich. If you do have a vacuum leak I'm thinking that your plugs are going to read way lean at cruise rpm. just pulling plugs won't really tell you because you can partially compensate for the lean fire by screwing out the mixture screws. So make sure you do it as above, holding it at cruise rpm and switching off the key. Next: Here comes the painful one. How did you do cam break in? there are many many reports of new cams going flat these days. Alot of it has to do with lack of zinc in newer motor oils. Alot of people are getting that lube from GM dealers and putting a quart of it in for break in, sorry can't remember the name right now. Next, you did the 2,000 rpm thing for 20 minutes right? Next, with the 1.6 ratio rockers and the over .500 lift cam, I'm sure you are running monster springs on your valves right? Well, did you pull off the inner springs for cam break in? I'm guessing but with the 1.6 rockers you are up in the .550- .570 range on lift, and I'm thinking you have whiped out a cam lobe due to high spring pressures on break in. You can start it, let it idle with a valve cover off and watch the rockers to see if they all move equal distances. Then pull the other valve cover and repeat. Its messy, but the only other way to check is to put a micrometer on the cam or edge of the lifters to check. If you have a flat cam, you wil see one rocker doesn't appear to move as much as the others. Hopefully thats not it. Comp recommends running basically stock springs to break in any flat tappet cam, then after break in is complete swapping to your big springs. check your oil, its normal on a new engine to have the oil look like a letallic paint, VERY fine specs of metal. however, if you have any flakes, or actual small pieces, its another indicator your cam is having itself for dinner. (eating itself) Good luck. Scot
did the cruise idol shut off thing a little black not fouled. 20 min cam break in at 2000 rpm. didmt have the 1.6 rollers on it have 1.46 springs rated to 600 lift suposedly. i bought the heads ***embled and gave them my specs got em from ebay see listing http://cgi.ebay.com/ebaymotors/SBC-CHEVY-CYLINDER-HEADS-195-CC-ALUMINUM_W0QQcmdZViewItemQQcategoryZ33617QQihZ016QQitemZ260053206925QQrdZ1 i am hoping to find a hamber in my area or someone i just dont know...oil looks good
well put a different carb on it an edlbrock 600 i had. seemed to help alot still loses 4-500 rpm when i put in gear but dosent die. still trying to get the timing right. still tryin to get float etc right but this definatly helped. thanks to gofast62 the phone calls helped! so just keepin all yall up to date. gettin dark here soon so i will have to continue tomorow thanks for the help so far....
One more tidbit then Im out of ideas here![I STILL WORRY ABOUT YOUR DISTRIBUTOR] Check the surface of intake where your carb bolts on for square/flat..........i had one leak there but could not see it with the naked eye......I presume carb base is not warped or bent in any way?
Most of the problem is in the crab adustments like everyone said. I dont know what gas you are useing, but you have a low compression motor so a high octane fuel will increase fuel trim and timimg. The more fuel there is in the chamber the longer it will have to burn the fuel so it will retard the timing to get proper atomization to burn the fuel. The motor seems like a well built motor. Carb is out of adjustment, but there are a few things you can do to fix the problem. The first would be adjust the carb which may never adjust out right for the motor combo you have, so you may wanna go with a little smaller carb you wont get all that fuel that you dont need. 2 Points or HEI, dont want to get rid of all that fuel get a hotter burn. or 3 put a gear drive in it, it will spit, fart, and do all kids of crazy **** but it will stay in time. Personally i would go with a smaller carb or the HEI.
one more thing and this may not sound like a good idea, but it works. If you have a set of maifolds or headers you dont use this is a good idea. Go out buy a couple O2 sensores and an air fuel ration gauge, drill the manifold and put it in and hook up the gauge. Good AF ratio would be in the 14:1 range perfect being 14.7:1. Adjust the card when you have them hooked up it will help you get the adjustments close. if the mixture stays too rich its fuel. if the motor still runs bad but you get a lean burn. you may be a spark issue. thats all i got but hey its worth a shot maybe.
boynamedsue, it is an hei. i am leaning twords staying with the edelbrock is a 600cfm a big enough carb or should i go to a 750 performer or thunder? got all white plugs now. dont think the ele choke is working. still get a significant drop in rpm at idle in gear gonna play with different springs and weights in the dizzy to try and get a better advance curve. any suggestions from anyone. got the heavy springs in now gonna go a little lighter. got it down the road today with no spark rattle bot some dieseling on shut down. ran like a scalded dog!! couldnt keep the tires on the pavement!! would adding an msd box help any? would this give me a hotter or better spark? plugs are clean and white? can u put this engine on like a sun diagnostics machine? if i can find someone would this allow me to correctly dial in the carb? thanks for still paying attention to this thread there is some informative **** on here ive gone back and read it like 10 times......WOW
well got it runnin but still not 100% but gettin closer watch the video.. http://www.youtube.com/watch?v=EAluv_tomys
as soon as it quits stormin around here im gonna get her out on the street and burn the tires off her!!! thanks for everyones help put lighter springs in my dizzy all in at 2500 and sharper curve. mech starts now about 1300. seems much better. put some octane booster in, will this hurt anything? tried to hook up an old 6a msd box i had but the box is shot. dose anyone thing adding a box would help any? better spark?
yep. especially with a nice high compression ratio. it allows you to take a *touch* of advance out of it. send it to m.s.d.- thier repair services are damn reasonable. and take it easy on the burnouts till the motor is broken in.
Did you try it with the brake booster vacuum hose unhooked and plugged? I had one car give me fits because it had a pinhole leak and when I put the car in gear it would idle real low and die. This was regardless of me having my foot on the brake pedal or not. It sounds like a vacuum leak and throwing bunches of new parts at it won't solve the problem. This is just my .02 worth on the subject.
tried it with the booster unpluged put on park brake and ran it in gear. same thing. iv re sealed everything. vac guage is steady till i put her in gear then because of rpm loss (i think) it drops to 5-7. on steady gas to 3000 rpm it will pull 20 steady. i am not trying to throw parts at it i had a msd box and thought maby a combo of weak gas, mis adj carb and dropped compression at idle with such a big cam maby hotter spark would help. iv had some local guys tell me id never get it to idle with such a big cam and an auto ******. is this true i have an acc 3000 stall. it seems to do better with some oct boost and the edelbrock i had. gonna adjust that if it quits rainin. the hotter plugs helped. is there an easier way to check for vac leak than guessing? someone tell me the propper procedure or what to look for.
Judging from the video, it seems pretty okay to me. Idles at 1,000, drops 200 rpm or so to 800 in gear...hell, I can live with that. A little lower would be a little better, but it sure sounds like you're real close to being right on now. Oh - I normally wouldn't say this, but I feel overwhelmingly compelled... Boynamedsue - that is the absolute worst advice I've ever seen here on the HAMB.... ...there's no shame in watching from the sidelines sometimes Amigo. Please- unless you know EXACTLY what the **** your talking about, don't offer advice to a guy who really needs help. ~Scotch~
still have some slight spark rattlt (pinging) on slight gas at speed. meaning if im crusin at say 2500 and barley step on it it will ping a little and stop about 3500 but if i step on it harder no pinging. im gonna try to limit the mech adv to 18 its 21 now and slow the curve one more level. its kinda cool this dizzy alows these adjustments. seems to be a little lean also ( exh smells like gas) but drove her all around today, maby 50 miles seems ok. oh and im getting some dieseling on shut down. i just turn it off in gear is this ok? maby when i get the dizzy and carb right it wont, but is it ok to turn it off in gear? thanks for everyones help ill post a better video soon
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