Ford Mustang Forums banner

1 - 2 of 2 Posts

·
Registered
Joined
·
43 Posts
Discussion Starter #1 (Edited)
Is it better to go with a stocker cam with big-valved heads or a bigger cam with smaller valves?

I'm trying to figure out if, assuming a NA daily driver with occasional nitrous use at the track, trying to build a 9-9.5:1 compression motor would be able to produce more power with say a bigger cam and Thumper style heads, or a more docile cam and Roush 200's or something.

Obviously I haven't gotten the whole airflow/air velocity thing down yet.:eek:
 

·
Registered
Joined
·
180 Posts
Ideally you would want a head that flows better (not necessarily a bigger valve, but that can help) and a cam to complement your heads and induction system. The bigger cam with heads that dont flow well wont make any power and will not be fun to drive.
The smaller cam with better flowing heads and intake system will make more power than stock heads of course but still be very driveable.

I would want to know more about the combination that you are wanting to build. What size will this engine be? The bigger the engine the more power you can make without making the engine a turd at low rpm's. Will the new engine be carbed or injected?

As far as the "airflow and velocity thing" goes, for anything approaching low rpm power you should try using a head that will have enough airflow to get the job done. For instance if you are wanting to build a 500 hp street engine you could get the job done with a head that flows around 260 cfm and has a 2.02 valve.
If you used a 340 cfm head with a 2.125 valve (enough air flow for over 700 hp ) you could sog out your bottom end and possibly not be able to produce the kind of piston speed needed to have good velocity through the ports up high. Another thing to consider is engine size. The bigger you make the engine the more power you can make while staying away from ultra high rpm's and maintaining driveability.
 
1 - 2 of 2 Posts
Top