Help Supercharged 1.9 Power Drop

[tcr 13 2 Cars]

After a couple of hours on the rolling road I'm unable to figure out what's causing the substantial power drop at 6200rpm , I'm running 440cc injectors , dta engine management 1:1 adjustable fuel reg Kent pt37 cam ( 2250 - 7000 power band ) in a ported flowed matched head ,

Anyone got any ideas what could be causing the restriction ?

[welshpug 1,626]

cam timing? not enough valves?

[tcr 13 2 Cars]

Played about with the cam timing but still nothing after 6200

[stef205 91 1 Cars]

are you using recirculating valves or dump valves? belt not slipping?

[tcr 13 2 Cars]

It's running a recirc system and a new belt was fitted one week previous

[allanallen 528 2 Cars]

What charger? What's boost pressure doing at 6200rpm?

[stef205 91 1 Cars]

I would check the new belt isn't slipping at high rpm and your recirculating valve isn't leaking at high boost

[tcr 13 2 Cars]

It's an m45 charger holding steady at 7psi on WOT with no drop in boost

[cheesegrater 43 1 Cars]

How come you're using an adjustable reg. Id be using a rising rate reg personally.

[Vili 17]

What are your inlet temperatures?

[tcr 13 2 Cars]

Inlet temp is in the 80's but iv seen them higher on my old s/c mx5

[stef205 91 1 Cars]

what size pulley is on the charger? its possible you maybe over revving it.

[tcr 13 2 Cars]

It's the standard m45 pulley