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Re: $12P Idle MAP Threshold VS Idle RPM
Posted: Thu Sep 12, 2013 10:20 pm
by Holden202T
I reckon you'll find it won't want to happily idle much below where it is now and the lower you go the more vacuum you'll loose!!
Re: $12P Idle MAP Threshold VS Idle RPM
Posted: Thu Sep 12, 2013 10:21 pm
by vlad01
here is a video that explains it very well.
[youtube]
http://www.youtube.com/watch?v=tMZhhLWuP84#t=352[/youtube]
Re: $12P Idle MAP Threshold VS Idle RPM
Posted: Thu Sep 12, 2013 11:42 pm
by Dylan
Holden202T wrote:I reckon you'll find it won't want to happily idle much below where it is now and the lower you go the more vacuum you'll loose!!
Not that I've got much to start with. Although the cannister I fitted inline with my booster helped my brakes and idle.
Re: $12P Idle MAP Threshold VS Idle RPM
Posted: Fri Sep 13, 2013 7:54 am
by immortality
Dylan wrote:Holden202T wrote:I reckon you'll find it won't want to happily idle much below where it is now and the lower you go the more vacuum you'll loose!!
Not that I've got much to start with. Although the cannister I fitted inline with my booster helped my brakes and idle.
Try adding in as much timing as possible at idle to bring up the vacuum.
Re: $12P Idle MAP Threshold VS Idle RPM
Posted: Fri Sep 13, 2013 7:56 am
by immortality
vlad01 wrote:the problem is, "flat tappet" setup isn't actually flat. they are convex slightly and the lobes are slopped to one side and center offset from the lifter slightly. This effective makes the lifter rotate and roll around the lobe.
the lifter must rotate at all times, if they don't the setup is wrong they they will fail immediately. Also they need to be lubricated at all times during the crucial break in period. Oil doesn't cut it unless there is a manganese oxide? coating to make the oil stick to it. That black coating they come with.
Spot on, the lifters really need to be matched to the cam to ensure the angles are all correct.
I have heard some guys use a spray on molly coating on the cam lobes when fitting as well as the cam lube to ensure lubrication during the first start-up.
Re: $12P Idle MAP Threshold VS Idle RPM
Posted: Fri Sep 13, 2013 12:25 pm
by delcowizzid
the torana we just fired up had cam lube but it then sat for nearly a year before starting seems ok at the moment number 1 cylinder is noisier than the rest its just a waiting game LOL
Re: $12P Idle MAP Threshold VS Idle RPM
Posted: Fri Sep 13, 2013 12:29 pm
by vlad01
I much prefer roller lifters lol or over head cam with roller rockers like suby SOHC engines have.
Re: $12P Idle MAP Threshold VS Idle RPM
Posted: Fri Sep 13, 2013 1:31 pm
by Holden202T
well i haven't had alot of experience with V8's, more with holden 6's but in both cases i've never managed to wipe out a cam lobe using the cam manufacturers run in procedures!
Re: $12P Idle MAP Threshold VS Idle RPM
Posted: Fri Sep 13, 2013 4:29 pm
by delcowizzid
haha back in the day when i had 4 cylinder 4K toyotas i swapped cams and lifters between engines all the time allways with lifters in the wrong order etc and never killed a lobe.chevs and holdens can be more prone to chewing lobes especially with spring pressures over 130Lb.full race solid lifter cams dont have a long life expectancy 1 or 2 drag seasons and they go in the scrap pile round here
Re: $12P Idle MAP Threshold VS Idle RPM
Posted: Fri Sep 13, 2013 7:24 pm
by vlad01
I have seen so many stock holden v8 wear out lobs it just makes me think v8s are shit in general lol
They have some major design problems, think lubrication to the cam is a major one for the holden v8.