More SRM SMIC Flow Testing

I have a set of SRM SMICs on hand that differ from the ones on my S4 with respect to the end tanks.  These new arrivals have cast end tanks.

The cast end tanks look smoother than the end tanks I am using which might lead to a slight improvement in airflow, but something else that has changed is that the inlet and outlet piping are a bit thicker than on the welded end tank.

The inner diameter of the inlet/outlet on my ICs is 2.375″, on these cast tanks the inner diameter is 2.18″, this could be a detriment to better airflow.

I put the driver side intercooler onto the flow bench to get a reading without any piping on the inlet side.

SRM Cast End Tank SMIC
SRM Cast End Tank SMIC

This arrangement flowed 301 CFM @ 28″ of H2O.

Next I attached the supplied SRM intake coupler hose and retested.

SRM Cast End Tank SMIC
SRM Cast End Tank SMIC

The flow dropped as expected, down to 279 CFM @ 28″ of H2O.

As a final check I attached the rest of the inlet piping that would connect the intercooler to the turbocharger.

Silly Rabbit Motorsport Cast End Tank Intercooler
Silly Rabbit Motorsport Cast End Tank Intercooler

The airflow dropped further, down to 228 CFM @ 28″ of H2O.

The drop in airflow with additional inlet piping is not unexpected and lacking a comparison intercooler these numbers don’t tell much.

SRM Cast End Tank Airflow Summary
SRM Cast End Tank Airflow Summary

Tomorrow I plan to run a similar series of tests with the White Dog Racing side mount intercooler to see how it compares.

Upgrade downhill

I’ve finally reached the point of starting to put parts back onto this engine for the Silver S4 that I have made some upgrades to and have been performing maintenance on.

The XS-Power turbo inlets fit poorly so I cut the ends off near the compressor housing and fit silicone couplers instead.

B5 S4 Engine
B5 S4 Engine

The XS-Power downpipes fit well so far.

The same cannot be said for the XS-Power Bipipe that fits poorly.  The pipes are in contact with the cam covers but there is still another eighth of an inch or so that the bipipe needs to seat further onto the throttle body.

May be time to look into a better quality bipipe; i.e used APR Bipipe.