M42club.com - Home of the BMW E30/E36 318i/iS

DISCUSSION => Swaps, Turbos, Buildups => Topic started by: hammoj28 on May 23, 2007, 06:39:19 PM

Title: E36 M3 throttle bodies vs Bike throttle bodies?
Post by: hammoj28 on May 23, 2007, 06:39:19 PM

Basically what would be better? For power/ease of fitting and cost? I have been trawling through threads on here and both setups look good.

So, as i have seen steve321's m3 throttle body setup and it looks awesome, i was going to go with that but theres a small part of me that wants to go with bike itb's. I see the advantage is that you could run them on a sock filter as Tim mentioned in a post instead of having an airbox manufactured which is one advantage and noise isn't a problem? but i have heard somewhere that they are harder to set up?

Whats your opinions? I am going for top end mods mostly including cams, the above, lightened flywheel and mega squirt and possibly polished, ported head.

Any advice would be much appreciated. Just wanna know whats the better option. I am swaying towards the M3 throttle bodies at the mo btw.

Thanks

James.

Title: E36 M3 throttle bodies vs Bike throttle bodies?
Post by: dino245 on May 28, 2007, 12:23:54 PM

The E30 M3 throttle bodies are spaced at 100mm apart like the cyl. spacing of the S14/M10 ro M30 engines. The M42 has a bore spacing of 91mm like the M5x/S5x or M20 and M42. If you wanted something closer to stock find some european market S50 throttle bodies but even these need some modifications to make them work, but it can be done look at tim_s he has done this. For us on this side of the pond use Motorcycle throttle bodies I would sudgest early Hayabusa.

Title: E36 M3 throttle bodies vs Bike throttle bodies?
Post by: Boyracer on June 07, 2007, 05:48:45 AM

M3's S50 engine throttle bodies for teh win. They have same cylinder spacing as M42, also their diameter is spot on.

Bike throttle bodies have the problem that their throttle plates are angled too shallow when they are closed, I think around 10-15 degrees. M3 TB's are more like 2-3 degrees.

This means that same rotation of throttle plate will allow much more air to engine on bike tb's compared to M3 tb's. This will make slow speed driving very interesting.

I guess you could manufacture somekind of variable rate system to bike tb's to make them less sensitive on small throttle openings but I think it will never be as good as M3 tb's.

Title: E36 M3 throttle bodies vs Bike throttle bodies?
Post by: dino245 on June 07, 2007, 08:36:24 AM

I have purchased a set of S50 ITB's and will be using these instead of the Hayabusa throttle bodies, I had a change of mind and sold the ITB's on ebay. I like the factory S50 throttle bodies better.

Title: E36 M3 throttle bodies vs Bike throttle bodies?
Post by: hammoj28 on August 18, 2007, 11:41:20 AM

Cheers for the replies. S50 seems to be the best bet.