Exocet on Dyno...

[theancientone]

Our Exocet with MP62 had 4 rib pulleys and an OEM TB on the s/c. It made about 240bhp and 200lbft at the flywheel.
We recently changed to 6 rib pulleys and a 70mm TB on the MP62. Being a little nervous that the engine might then run lean saw us get the car on the Dyno yesterday.
The car made 276bhp and 230lbft at the flywheel. I'll post the graphs when I can sort out a host for the photographs.
Looks like we're on, or beyond, the limit of stock internals.
The 240bhp and 276bhp results were on the same Dyno with the same operator so I guess there's some relative validity.
Dyno was Evotune near Durham, with A K Automotive in attendance. A K suggested it might be as well to have a spare engine handy.

[gwnwar]

Numbers sound high. What kind of dyno and last time it was calibrated.. What PSI, Rpms were your peak readings, what engine management are you running.. Only mod is the nose pulley is it a 70 or 68.. no crank pulley overlay.. OEM throttle body.

[theancientone]

Megasquirt 3.
With 4 rib pulleys and OEM TB on MP62 maximum boost was 10psi. With 6 rib pulleys and 70mm TB on MP62 maximum boost was 13.5 psi. 6 rib pulleys are same ratio as the 4 rib.....130 / 62.5 = 2.08.
Doesn't matter if the Dyno figures are correct in absolute terms. It's the relative improvement which is important to us.
Evotune are renowned tuners of Evo's, WRX's, Sti's, Skylines etc etc.
A K Automotive are respected MX5 specialists.

[theancientone]

Graphs.....

[davetherave]

Any pics of the engine are you running a intercooler as well

[theancientone]

Yes....it's an 'over the top' intercooler. I'll get some shots of the engine in the next couple of days.

[davetherave]

Thanks