is 70mm big enough for an exhaust

[matto]

at what point power wise would 70mm exhaust bore become a restriction?
thanks
matt

[RobbieRX-7]

the standard system is 65mm so your only going 5mm bigger, not really worth it imo

[probedb]

3" (76mm) is good for well over 300 @ the wheels apparently.

[TRex]

A 70mm bore is v.good for a stock car and for a small/fair increase in mods.
As a matter of fact, I would say more than good enough for the twins at most stage of the cars mods.  
 
 But saying all this depends highly on the type of Exhaust system you want.  You can have a 70mm quality built, with very good flow characteristics exhaust that will out perform a bigger bore exhaust.

 Remember, Size does not matter! :Nono!

[stylus350]

I have 3" EXTERNAL bore and make 500+ fly at 1.1 on a single, so think your ok, depends what mods you are considering/running.

[matto]

thanks for the replies the exhaust in question is the gram lights weight concept:
//www.mackinindustries.com/md/rays/57dragonexhaust.html
i plan to run a single turbo and break the 400bhp @ wheels barrier i liked the looks of it and it seems fairly quiet at 92db so would it be up to the job?

[TRex]

Hhmmmm, nice choice. :Thumbs-up

 I don\'t see why not, once the rest of your system is set up to match this.. then you should have the best of both worlds.  

 Stylus has giving a very good example....