Kadunza S54 ITB Adapter Plate Project

[digger]

Wow, I knew the M50 intake was a bit off on the flow but that really put it into perspective. I wonder if that explains the common drop of torque you see in most S52's swapped with the M50 intake. Almost every dyno I see has a drop then a rise around 3k or so.

Wonder if I was to use this adapter for the S54 ITB's what intake would I use?

the effect i showed is not a low rpm thing, it would show up once you started to make power and as the mass flow levels increase would slowly get worse. everyone who has logged AFR for individual cylinders says the same thing there is heaps of variation more than you think with OEM type manifolds. AFR with a single sensor is an average.

i would use the stock one or modified stock one if it fit purely as a start point and go from there once you know the exact space envelope....i cant see it being the best thing for this combo but you need to start somewhere

[Aviator]

m50 all runners drawing (flow is 3.2L 100% VE 8000rpm)



angled entry all runners drawing (flow is 3.2L 100% VE 8000rpm)



All runners never are drawing at the same time only 2 to 2.5 runners are drawing depending on cam duration


m50 runners 1&4 drawing (flow is 3.2L 100% VE 8000rpm) 11% variance



angled entry runners 1&4 drawing (flow is 3.2L 100% VE 8000rpm)
2.5% variance



no questions that the angled entry provides better distribution. with the OEM runners 3 & 4 see more flow than its neighbours due to the poor design. air just dumps into the volume and the velocity of the air means it has difficulty turning corners.

most people flow test individual runners but that is useless for looking at distribution

Wow, I knew the M50 intake was a bit off on the flow but that really put it into perspective. I wonder if that explains the common drop of torque you see in most S52's swapped with the M50 intake. Almost every dyno I see has a drop then a rise around 3k or so.

Wonder if I was to use this adapter for the S54 ITB's what intake would I use?

[rzerob]

Subscribed

[achtunge30]

sub'd

[klodkrawler05]

subscribed for updates! This gives me more motivation to get cracking on my s52 ITB project!

[digger]

yeah the flow of individual runners is still important because this shows flow potential.

if flowing each runner in isolation shows differences these are most likely to be from different geometry of the runner itself. however since all the m50 runners are the same size and shape then the flow will be similar in each when flowed individually. The plenum is large and the entry is large as well so these wont affect flow bench results as much as the runners themselves.

with say the m20 this is not the case some runners have much tighter bends and internal casting details that leave alot to be desired.

the plenum would need to be particularly terrible to show uneven flow on the flow bench on a manifold where runners are identical

[wazzu70]

Digger, you are right that the numbers I have seen were flow for individual runners. Your analysis using two cylinders pulling at the same time gives a lot of great info! I stand corrected :)

[digger]

The center inlet on the M5x manifolds is actually quote good. Better than many side inlet style manifolds. The side inlet is done mainly for packaging reasons.

The flow to each runner in the center inlet manifolds is pretty well matched. Your main improvements would be in the length and taper angle of the manifold runners.

m50 all runners drawing (flow is 3.2L 100% VE 8000rpm)



angled entry all runners drawing (flow is 3.2L 100% VE 8000rpm)



All runners never are drawing at the same time only 2 to 2.5 runners are drawing depending on cam duration


m50 runners 1&4 drawing (flow is 3.2L 100% VE 8000rpm) 11% variance



angled entry runners 1&4 drawing (flow is 3.2L 100% VE 8000rpm)
2.5% variance



no questions that the angled entry provides better distribution. with the OEM runners 3 & 4 see more flow than its neighbours due to the poor design. air just dumps into the volume and the velocity of the air means it has difficulty turning corners.

most people flow test individual runners but that is useless for looking at distribution

[RobertK]

You care enough to keep shitting in the man's thread.

Can't blame the guy, I'd be pretty ornery too if I dropped $10k into a stock eta.

Grade A Google desktop mechanic. He seems to know so much for someone who has done so little for the community.

[agent]

You care enough to keep shitting in the man's thread.

[pantelones]

I know I should not bother, but...

for example a BMW m3 engine has 50mm ITB but they also have 2 very long ports in the head that are only equivalent diameter of 37mm this is the high velocity section of the intake and the butterfly is effectively out near the bell-mouth. This is why everyone who adapts M3 ITB”s onto other engines results in a spectacular failure!

http://www.racehead.com.au/?page_id=211

Pick the "low hanging fruit" to pick on, I could care less...

[wazzu70]

The CSL plenum is gigantic so there is no chance of air starvation to any of the cylinders. Also, the tuning is alpha N so there is no MAF or anything on the end to make the setup possible.

The side entry can work fine, but in most peoples cases its worse than factory due to poor design.

[digger]

The center inlet on the M5x manifolds is actually quote good. Better than many side inlet style manifolds. The side inlet is done mainly for packaging reasons.

The flow to each runner in the center inlet manifolds is pretty well matched. Your main improvements would be in the length and taper angle of the manifold runners.

IMO the central inlet is done for packaging reasons on BMW inline 6's. imagine trying to fit an airbox/filter assembly then a bit of pipe then the MAF between the engine and radiator.

the ebay manifold copies the basic chosen layout for performance manifolds for inline 6 engines including the CSL and it not really a side entry say like the M70. BMW changed the CSL to the angled entry from the regular S54 central entry not for packaging reasons at all. it offers well defined performance improvements when done correctly

[wazzu70]

The center inlet on the M5x manifolds is actually quote good. Better than many side inlet style manifolds. The side inlet is done mainly for packaging reasons.

The flow to each runner in the center inlet manifolds is pretty well matched. Your main improvements would be in the length and taper angle of the manifold runners.

[flyboyx]

where do you get an 80-100mm throttle body? 540i?