9a valver on k-jet & throttle bodies

[sambo 0]

Hello there. I had this idea of scraping standard air intake manifold set up on my valver and fit gsxr th. bodies but still keep k-jet. Some time ago i was told by vw motorsport mechanic that standard manifold is very badly designed and robs power for many reasons like long air path and heat bild up. So say i graft 4 th. bodies to front of the engine and make intake box to mate up to k-jet meetering head. All vacum connections could be retained as well as throttle switch. Surely responsivness and power should be way better. Has anyone done this before? Should be fun trying :)

[Kevin Bacon 5]

VW played with the 16V manifold a few times in an effort to improve torque, but they were never really happy with the engine in all honesty, so VWM telling you that comes as no surprise. What the mechanic didn't tell you is the shorter the inlet tract, the less usable torque you get - in theory at least. There have been some awesome throttle bodied 16Vs over the years but they don't make for a paticularly good road engine. Track use, yeah!

[sambo 0]

To be honest he said to me the oposite! Aparently the lower section is the bad one as thats where the air mass its lost as the travel is to long! One day they have played with it and they choped of about 1.1/2 inch out of it and welded it back together, and R.Roaded it. Power and torque went up by about 15 bhp/ft! The bonnet wouldnt close because of an angle manifold was. :lol:

[aide 0]

glad someone bought this subject up as i'm intending to weld the box section of the upper manifold to the lower section of the manifold, thereby reducing heat gain and shortening the induction tract.. as kev says the gas speed is theoretically key for torque and the longer/ straigter the tract the quicker the gas speed.

 

i've seen an astra 16v with a manifold in similar vain to suggestion above on the web somewhere, and whilst there was only a 1bhp gain the fella reckoned torque curve was flattended/ improved by the mod.... i'm looking to do the mod regardless but won't be this side of christmas :D as its unusual i'll definitely be posting it up

[aide 0]

apologies for hijacking your thread a bit sambo, but link is here for the astra one - not sure what original astra manifold is like though?

 

http://www.tomstickland.co.uk/astra/mod ... htm#inlet1

[PeterMunns 0]

sambo,

 

Keep us informed sound good if it works.. :?: :!:

[sambo 0]

One can only try it and see!