Aftermarket cams with extra HPFP lobes
 

I see now there's some new aftermarket cams available.

If I'm not mistaken, the HPFP is driven by the cams, and the HPFP cam lobes there are 2 lobes?

Has anyone played around with the idea of 3 or 4 lobe HPFP cams?

Someone mentioned to me that other brands (Mazda I think it was he mentioned) they can improve/increase flow/pressure on the HPFP.

Maybe with a sooped up HPFP more power might be gained, or is the present setup ample?

the Mazda's are getting more out of there systems with upgraded pump internals. I dought you will see cams with extra lobes as getting the new cores done will be costly and I dought anyone is spending the money to test extra lobes for the di pump. As well it is a mechanical part being cycled at a relatively high speed, and increasing its speed may have its own issues that need to be dealt with.

Is anyone having issues with the HP fuel pressure dropping out?

There are definitely three lobes on the HPFP cam.

theres no known issues with the fuel pump(other than noise)...so....until then?

If you are having issues of HPFP pressure dropping out, first thing to look at is improper in tank fuel pump install.

No issues. I thought that maybe running the HPFP harder might allow larger DI injectors.

I just remember talking with my tuner about DI only cars and what they did to get more power.

I was only saying if someone is having issues. If not, then why change?

I didn't mean you personally more anyone having issues.

The point in changing the hpfp would be to have more fuel to deliver but I find it pointless with many in tank options that allow tons of fuel delivery.

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Right, but our cars aren't DI only. I know other DI only platforms have explored adding aftermarket port injection systems for fuel delivery. We already have that from the factory. There isn't much point to upgrading DI unless we actually run into problems with that system.

I guess that was my roundabout question/comment: do we ned more fuel on the hp side

On a side note: someone needs to develop a return system with a sump tank that is almost pnp.

Im getting starvation at 5/8ths of a tank already :(

FBM and Dynosty are pretty close to PnP will get with a return system.

We will never need larger di injectors. High rpm/hp applications will always benefit from the increased fuel from coming upstream of the valve. Motorcycles have been running two sets of injectors per cylinder long before car and tbey have it figured out. The bigger injector is faaaar upstream and only turns on when needed. Similar to how our di pi system should operate.

My Ducati 998S had shower type injectors.
They fires before the throttle body.

Best response of any engine I have ever tried. Smooth like butter.

The misfires in the airbox, however, were pretty interesting:laughabove: