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View Full Version : importance of cam timing on a nova


S_Gault
11-06-04, 08:12 PM
Well just to prove what i keep saying , I had a wee rally car on dyno last night-

rough spec- 1300, cosworth pistons, mod head, AST3 cam, 40s etc.

cam in door with 86bhp!

left with 109bhp! and it was all cam timing and 4 jet changes!

Steven
novaboy1981
11-06-04, 08:29 PM
thats not bad!
Snowface
11-06-04, 08:30 PM
the ast3 must be mad.

where does the power kick in? is there a steep curve at 4k?
Adam
11-06-04, 08:51 PM
the ast3 must be mad.

where does the power kick in? is there a steep curve at 4k?

i think it kicks in at around 2K where it increases power quickly.
Will
12-06-04, 12:57 AM
Well just to prove what i keep saying , I had a wee rally car on dyno last night-

rough spec- 1300, cosworth pistons, mod head, AST3 cam, 40s etc.

cam in door with 86bhp!

left with 109bhp! and it was all cam timing and 4 jet changes!

Steven

wheels or flywheel figures sir?

very good results!
benji
12-06-04, 10:45 AM
wheels by the sound of it, does the ast3 need solid lifters?
rallyxnova
12-06-04, 09:07 PM
Steve..

I seen this car today at Nutts corner, it sounds unbelievable, and it sounds like it pulls from idle. I spoke with Ken the owner, hes dead chuffed!

Oh.. it won by the way, beating Marks SB developments engine!

Mark
S_Gault
13-06-04, 09:03 PM
an AST pulling from 4k!! who sets up your engines..

this pulls from 1500rpm relatively easily.

Yea Mark, Ken phoned me last night,

Steven
krobinson
13-06-04, 09:27 PM
How does the AST3 Cam compare to the piper 285 being used in my engine? Does it use solid or hydralic lifters?

Cheers

Keith
S_Gault
13-06-04, 11:09 PM
Its impossible to compare kent and piper profiles as they quote their durations on different check heights.

piper use zero clearance, kent tend too use .016in so 2 identical cams would give different numbers.

Steven
krobinson
13-06-04, 11:50 PM
Just checking up some info on the AST3 Cam..

AST3
Power band - 2500 - 7000
Cam Lift - 7.49mm
Valve Lift - 12.66mm
Duration - 280 Degrees

Keith
S_Gault
14-06-04, 06:24 PM
Its all pretty meaning less thou Keith,

eg- the power band varies on the build and where its dialled in at

the valve lift varies with the actual rocker ratio of the followers which changes when you cut valve seats etc

and the duration- if piper measured the same cam it would prob be a 300deg cam.

Steven