What MFI space cam to use with DC80 cam?

[MST0118]

Hey Guys,

I'm in the process of having my 69 injection pump built for a 2.8 rsr build. I am fairly certain that a 2.8 rsr space cam will be put in. The potential issue is synchronizing this space to the DC80 cam that I plan to use. So, I am trying to determine the best injection space cam to use that will closely sync with the DC80 cam.

When I compare the cam specs for a DC80, 906 (used on 2.8 rsr), and 3.0 rsr cam, it appears that the 3.0 rsr cam is closer to the DC80 cam as compared to a 906 cam when considering lobe separation angle, lift overlap, duration, and valve lift. This leads me to believe that I'd be better off with running a 3.0 rsr space cam in my injection pump instead of 2.8 rsr space cam even though my engine displacement is 2.8.

My most important question is what is the best space cam to use for a 2.8 race motor with a DC80 cam? A secondary question is whether there any adjustments that can be made to modify the DC80 camshaft so that it would synchronize more effectively with the correct MFI space cam for better tuning. For instance, does it make sense to slightly change the lobe separation angle of the DC80 cam so it is similar to the 3.0 rsr camshaft which matches to space cam or just leave it alone?

Appreciate any suggestions you have on this issue. I’ve been through this once before several years ago on a similar motor build and had to change out the space cam in the middle of dyno-tuning, so trying to avoid that same mistake.

Thanks.

[HawgRyder]

You might also list the rest of the specs for the engine....compression, ignition, etc.
It would help for others to help you.
Bob

[MST0118]

Okay. Good idea. here's most of parts/specs: Twin plug crank fire ignition, Mahle 2.8 pistons, 10.5 to 1 compression. Mag stacks bored at 46/41 with throttle bodies 41/39. Ex port 37. 2.7 heads ported 39/37 with 46/40 valves, ebs racing springs, titanium retainers, Carrillo rods, forged rockers, titanium wrist pins, mag 7r case prepped for racing, alum lght weight flywheel, 2.4 crank that armando is cross drilling strengthening balancing, rsr injection pump, dc80 cam, European headers.

[MST0118]

Anyone using DC80 cams with mfi? If so, what space cam are.You using in injection pump?

[356RS]

If you could locate a V-109 space cam from a EP/RLA 1 V1077 (3.0RSR) MFI pump you would be close. The DC-80 has more lift than the 3.0RSR camshafts, .035" more, so you would have to modify the space cam a little. No one in there right mind would do that to a rare V-109. You will need to modify a 2.0 S or 2.2 S space cam to match up with your engine specs & with the DC-80 cams. An engine dyno will be a must.

[MST0118]

Thank you very much. I was thinking that 3.0 rsr space cam would be closer.

[cmcfaul]

You will be a master at tuning MFI when you finally get it set up right. An AFR meter and good MFI tools are going to be critical.

Chris
73 911 E