V8 not revving beyond 4000rpm

[Bengt Sweden]

The engine is rebuilt with an aftermarket cam and the heads milled 1mm. The engine runs very strong at low revs but looses steam higher up. Any suggestions what it could be?

Bengt

[StrangeRover]

Have you experimented with advancing the ignition a couple of degrees to see if it extends the range upwards without detriment at the bottom-end of the range?
I am assuming that all's well with the ignition components and fuel supply.;)

[Satancom]

Is the dizzy advance working?

[landowner]

All of above and check carbs are opperating fully, and needles are in propperly if you have had them out.
The needles could be too week for the engine if it's on carbs that is.

Would go with Strangerovers ign advance advice though, make sure the vac pipes are on the right way etc and that it's advancing as it should.

I had a problem like this with a smaller engine once and it turned out that a carb manifold gasket had slipped during installation and was restricting the induction.

all things to think about.:)

[Bengt Sweden]

A -99 DII has electronic injection and ignition. So I need some other suggestions.
Bengt