Alright guys here's something that has me stumped... Ordered a ta84-88h for my 455 put it in set timing dot to dot fire it up runs rougher than a night in jail. Advance the dizzy about a plug and it smooths out and runs great...shut it off try to start it back has starter kickback and won't start unless I retard the timing. The. Advance it back to make it run right...anyone else have that issue before on a ta performance Schneider racing cam? Sent from my LG-H810 using Tapatalk
Did you degree it? Years ago I used to install cams "dot to dot" then wondered why I didn't have any low end, idled rough, not much vacuum, etc. I bought a degree wheel set up, took a bit of reading the instructions to understand, but once I had it figured out, WOW:laugh: My 310 and 413 cams I had in my 350 had TONS of low end Degree that cam, it does make a difference:TU:
I hope you understand the difference between valve timing and ignition timing, they are two different things. Putting a cam in dot to dot does not guarantee that it is in right. The valve timing can be off from where the cam card says. Degreeing the cam when you install it really is a must these days. It is not unusual for a cam to like more initial ignition timing too idle better. I'm not really clear how you advanced the ignition timing when you say "Advance the dizzy about a plug". Did you move the plug wires on the distributor one position? The distributor turns at 1/2 the crank speed, so 1* of distributor rotation equals 2* at the crank. Moving the plug wires will result in a huge timing increase. That will make the engine crank hard when hot and kick back and broken starters are a given. Do you have a timing light? See where the timing is and go from there. Put the plug wires back and rotate the distributor to make a smaller timing increase. Increasing the initial timing can make it idle better, but the mechanical and vacuum advance can add too much timing when you drive it.
Set CAM timing dot to dot. Set dist timing at 6* initial start WILL NOT idle until I advance dist to 24* initial. But like you said too much initial hard cranking and starter kickback Sent from my LG-H810 using Tapatalk
The specs on the TA 284-88H are 223*/230* at .050. The cam has a 110* LSA. The cam card probably tells you to degree the intake lobe to 106* ICL making the cam 4* advanced. Theoretically, in a perfect world, dot to dot would make the cam 4* advanced. That may or not be the case. Tolerances can stack up from the gears and/or cam grinding, and the fact is you can't be certain where it is set unless you check it when you install it. It helps to have a multi key way timing gear/chain set so you can adjust it to get it to agree with the cam card. Murphy's Law says the cam probably isn't in right. The 284-88H shouldn't need that much ignition advance to idle well. To run 24* initial timing will require you to reduce the mechanical timing down to about 10* otherwise you will over advance at higher RPM. You can run a start retard to deal with the hard cranking, but that would be a band aid.
Sounds like your balancer has slipped and isn't at zero at top dead center any longer. o No: 24 initial seems like at least double of what it should be, look at your balancer. GL Derek
I agree about the balancer and the necessity of degreeing the cam. I believe the mark on the balancer should line up with the keyway on the balancer? Can't quite remember.
its def not the balancer, bought the engine used done a compete rebuild. installed factory cam no issues and balancer lines up 0 perfectly... looks like ill be degreeing the new cam, just hope my 3 keyway chain will be enough to get it close Derek[/QUOTE]
Confirm TDC on your balancer as it would not be the first time that the outer ring has moved. Any Cam should be degreed other then maybe a factory Cam with a known set of proved out Crank and Cam gears!
Speaking from experience, having issues with both of these on my last build, I will now always degree my cam and verify balancer timing mark aligns at zero degrees. I had simlar symptoms to yours. Do this and I bet your problem will be solved.
Whatever you have to do to correct things if your at the timing gears install a 2 degree advance key to compensate for normal stretch of any chain set up under the Sun!
Running the same cam, degreed to the spec sheet and it is lumpy but not that bad. I'm running 12* initial @ 800 rpm in park. 650-700 rpm idle in gear.
There's ALSO been problems with the timing gears. Don't know if the problems have been solved since. BUT, as mentioned YOU NEED TO DEGREE THE CAM!!!!
