Grizzly

Ok, I'm about to build a Half Bridge motor, thing is there is so much info on the net i'm now confused.



I know the shape and size of the Bridge i need to cut out but the thing thats confusing me is the Angle? I have done lots of reading and noticed 60-70% of the Bridges are cut nearly square to the machined Surface (as lower pic), but saying this there is alot of people saying it needs to be cut at an Angle then the runner opened up so the Bridge acts a bit like a scoop (upper Pic).



All his being said i was talking to a guy my dad works with in the Aerospace Industry and he seemed to think it would make little diffrence becouse of the 90deg Turn at the end of the port (basicly creating resistance/Backing up as its Not as Efficant as the Strait runner) so he tells me it would proberly work better if the Bridge was Angled towards the 90deg bend in the runner so the effect of the Poor design 90deg helps push the air in) Does this sound plausable?



I'm sure by now i'm Confusing you so this is the Angle i'm trying to explaine in the Pic.

BDC

Hi Grizzly,



I'm a big, big advocate of bridgeporting. I'm one of those guys that pushes bridgeporting for street use, but I suppose I am a bit on the hardcore, unorthodox side. In any event, I've been messing with street-driven BP's for not quite 4 years now and I've done alot of BP cuts in my time since then. Alot of my experimentation has been derived from changing the cut size, width, heighth, placement, etc. to categorize differences. Basically, what it boils down to when it comes to this angular thing, is it doesn't seem to make much practical difference if at all. From what I can tell up to this point in my few years of experimenting with BP's, the biggest difference in terms of VE increase and engine power potential comes from just going from a low overlap port to a high overlap port (from going from a stock/street port to a BP). Otherwise, I can't see any real benefit to cutting the BP cut like that (atleast I haven't noticed any that can be empirically shown). I guess it's one of those things, Grizzly -- Some people say this or that, and that you "should" do this, or "that won't work", or whatever it is, but my vote is to listen to only those who've done this sort of thing. I'm one of those guys and I say ya ought not sweat over the angle of the bridgeport cut.



B

Grizzly

Thanks for that. I always get nervous just before i cut big holes in expencive bits of engine

ChainSawOnSteroids

JUST DO IT!!!!!!!!!!!

Grizzly

Yep only a Muppet would cut a Bridge not knowing/not sure what there doing in a brand new Plate