JPSC Forum

As some will know I have an Omex Supercharger Kit on my Zetec. The design/kit is marketed by Omex but was actually designed by TTS who are the UK distributor for Rotrax.

I've been concerned with inlet temps for a long time so I decided to pay TTS in Northampton a visit to see what is what. They spent an hour putting sensors and thermocouples all of the engine inlet so as to be able to measure the temps/pressures involved. The car was put on their Dyno and got up to temp, at which point we did some power runs.

Car made 339 BHP with 265 ft lb (TTS admit their Dyno is kind and this was wheel figures and are close to most dynos crank figures but it will be the comparison that is important)
Pressure drop was 5 psi over the inter-cooler (pressure out of the charger was 1.2 Bar)
Peak temp out of the supercharger was 115 deg C while peak temp in the inlet was 69 deg C, ambient was 15 deg C.

So pretty good power but terrible pressure loss and very high inlet. The engine had a misfire at high RPM which was caused by large plug gaps which they resolved

Car is going back next week for a custom inter-cooler and pipework based on their Honda Civic inter-cooler which drops 0.5 psi and sits at 15 deg C over ambient. They (TTS) tell me 1 psi in an engine like mine is 10-15 BHP and 10 deg C is worth another 10 BHP.

So.........all things being equal the car should be in the 380BHP range once the work is done

You know what they say...? Be carefull what you wish for, because you might just get it!

You'll finally be able to break those half-shafts?

Rotrax cars are 'soft' on transmission parts because of the way the power is delivered....will be fun though !

So why does your set-up drop pressure and why does their set-up not?
is the pressure not held in the intercooler and pipework so is there a leak in your system?

Sorry to sound a bit stupid but what am I missing

also how will it drop your inlet temperature.

efficiency....simple as that. Currently the intercooler is in-efficient and the new one will be better

The pressure drop is more to do with the ability to allow air to flow through without restriction. At high revs the engine is consuming air from the one side of the inter-cooler faster than it can flow through from the s/charger side. Once the revs drop the pressure equalises.

So I'm off to TTS for the customer intercooler build tomorrow....will be interesting to see what power it makes on their dyno.

Thats good timing Jeff just in time for Goodwood.

lol...you spotted that then