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Ronald Wendt
09-22-2009, 09:23 AM
How different are they?

If I have a cam from an automatic reground for my 5 speed would it matter in any way? I can't imagine but then with these cars I am always being surprised

thanks

Ron

Wagonman88
09-22-2009, 12:07 PM
If it's reground then no. The difference is between overlap and duration I believe. You can run either in any setup you'll just have issues with a big overlap cam in your auto cause it will want to stall out when put into gear due to the rough idle.

But if it's reground then the profile is completely changed to whatever you get it ground to.



Jeremy

fturner
09-22-2009, 12:10 PM
You mean the 5spd, not the auto in these cars. The auto cars are really resilient with big cams, but the 5spd's are very finicky even with a mild cam and requires advanced tuning to sort out.

Fraser

Wagonman88
09-22-2009, 12:54 PM
I meant in general. People run less of an overlap in autos so they won't stall. I'm new to the SC's and their tuning issues so I'm not sure. I don't see how tuning for a 5 speed transmission that uses a clutch you can control is more difficult than an automatic that you want to keep a good idle but not die on you when you put it in gear.



Jeremy

fturner
09-22-2009, 01:22 PM
In an auto, you have a big heavy Trq Convertor that helps to keep the motor spinning until the EEC resestablishes itself, and generally you don't see stalling with those since the landing down to idle is slower.

In a stick, you'll get alot of stalling when you declutch especially from higher rpm's unless either the tune has been corrected, or as in the old days bend tabs etc and crank open the throttle body etc to try to compensate and generally end up with a higher idle and flaring.

This is a Supercoupe, what you have experienced with other cars generally needs to be forgotten about when it comes to these cars ;).

Fraser

Wagonman88
09-22-2009, 01:32 PM
This is a Supercoupe, what you have experienced with other cars generally needs to be forgotten about when it comes to these cars ;).

Fraser

Haha, I'll have to keep that in mind!!

I can see the inertia from the torque converter helping to keep the motor running. Personal experience though, a buddy had an 81 camaro we swapped a 350 into with a big cam and he couldn't get it into gear unless he two footed it every time. Without a stall converter that is very dangerous as it wants to leap forward when it finally goes into gear.

I believe his overall question was is there any physical difference where these cams can not be interchangeable by, say journal size or timing gear bolt size. Please correct me if I'm wrong Ron.



Jeremy

fturner
09-22-2009, 02:20 PM
No differences....

Fraser

baer198
09-22-2009, 02:29 PM
I do be leave their is a post on here for parts , and a guy has a cam for the manual dirt cheap....

the-big-e
09-22-2009, 03:00 PM
This is a Supercoupe, what you have experienced with other cars generally needs to be forgotten about when it comes to these cars ;).

This is going to be my new catch phrase.....:D