Smooth Bore Induction Hose ?
Smooth Bore Induction Hose ?
Author
Discussion

daveb500

Original Poster:

391 posts

217 months

Wednesday 14th January 2009
quotequote all
I've got a small hole in the black pipe coming from the Plenum (looks like the dipstick has been rubbing on it at some point) and so I need to replace it. What are the benefits of the full "smooth bore" induction kits? I understand the logic behind it but does it make much difference on it's own or is it only really beneficial with other engine mods? Obviously I'm not expecting miracles.

Has anybody fitted one and noticed a difference?

thegman

1,928 posts

234 months

Wednesday 14th January 2009
quotequote all
I have one fitted. I have not noticed any difference except it looks better. Its meant to provide like 1 extra hp. Probably much less important than the wind direction....

900T-R

20,406 posts

287 months

Wednesday 14th January 2009
quotequote all
According to Joo as well as the owner of the place where we rolling road test all our road test cars, the 90 degree elbow from AMM to TB is the important one - IIRC Joo said it's an easy 5 hp (or so) to get.

daveb500

Original Poster:

391 posts

217 months

Wednesday 14th January 2009
quotequote all
Ok. So infact, the pipe that I need to replace (the 90 deg. bend) is the bit that makes the most difference then. Question is, do I spend £30 to be practical or £120 to make it look nice....confused

rev-erend

21,622 posts

314 months

Wednesday 14th January 2009
quotequote all
Best put a bit of duct tape on it for now.. smile

900T-R

20,406 posts

287 months

Wednesday 14th January 2009
quotequote all
daveb500 said:
Ok. So infact, the pipe that I need to replace (the 90 deg. bend) is the bit that makes the most difference then. Question is, do I spend £30 to be practical or £120 to make it look nice....confused
I spent not even that to make it practical and nice - a 135 degree silicone bend has longer legs than the 90 degree ones, so I took one and cut it off at 90 degrees (for some reason, this worked better with the 70 mm ID bend for the standard sized throttle than with the 76 mm one that replaced it, but then I had a mission getting it to fit on the AMM side as that's 80 mm... eek).



Old 70 mm version which I still have in my basement storage - a cast-iron b**ch to put on at the AMM side, though. wink

spend

12,581 posts

281 months

Wednesday 14th January 2009
quotequote all
The resistance to deformation is just as important (probably more in fact) than the smoothness in the total induction. The smoothness seems particularly effective in the AFM-plenum, and the resistance to collapse in the filter-AFM IMHO wink

900T-R

20,406 posts

287 months

Wednesday 14th January 2009
quotequote all
So the above combo must be just about optimal, then. wink

Uncle Fester

3,114 posts

238 months

Wednesday 14th January 2009
quotequote all
Has anyone tried relocating the AFM?

What would happen if the AFM were rotated 90 degrees so the path of the air was a straight line from AFM to throttle body?

Then move the bend to before the AFM.


rev-erend

21,622 posts

314 months

Wednesday 14th January 2009
quotequote all
900T-R said:
daveb500 said:
Ok. So infact, the pipe that I need to replace (the 90 deg. bend) is the bit that makes the most difference then. Question is, do I spend £30 to be practical or £120 to make it look nice....confused

quote]

That must have been loud .. if you started it hehe