Vcm9 with 1.8rr compaired to ?

[Johnn]

2012 r8 ls3 m6
Otr & full 3"
Car is daily driven in city peek hour by misses
Was looking at vcm21 but it seem the 9 pulls more torque (about 40nm below 3k)
So was thinking dropping 1.8 RR to give a bit more power and maintain drivability
Thoughts?
Thanks first post

[white lie]

Your post doesn't make a lot of sense but I assume you want to run 1.8:1 roller rockers with either the VCM 9 or 21? In either case, they both have 0.600" lift on a 1.7 rocker, this will become 0.635 with 1.8's. You may struggle for clearance.

I would just run the 21, they're both small grinds anyway, with the 9 being very small IMO.

[Xjas]

Either cam should make more power than stock across the whole RPM range, can't comment on the VCM 9 but my 6L with a VCM 21 drives almost like stock (and would probably be better with a pro tune), gets better fuel economy than stock and its our only car so the missus drives it everywhere.

[Johnn]

Sorry about being a bit confusing
Was looking at vcm9 with 1.8rr compaired to vcm21

Car just came out of warranty so I have brought a vcm otr and diflippo 1 3/4 with dual 3"
Witch I will fit the weekend before having cam done so as to save a bit on installation
Normaly I would do the hole lot but don't have time when wife drives it daily

Because she drives in city peek hour I need something with good bottom end that won't be a pain to drive
Prior ride a vs statesman with 286 cam and 2500 stall with 3.5 rear

This car being a manual makes it a bit different if it was auto I would just stall it and go sometime in the 224/232 range

I have a dump of a vcm3 compaired to 9 hence why I was looking at the 9

[IJ.]

So you're going to install headers and then have someone remove them and refit them when they do the Cam install?

Might be easier to ask them to install them as part of the Cam job, shouldn't cost anymore as they're already removing the old parts...

[white lie]

The 21 will drive a hell of a lot nicer than a 5L with a 286. I really think you'll be left feeling like you want a bit more with the 9 and again, not sure it will fit with .635" lift on the intake with 1.8's. If you want more from the 9, you may as well keep the same lift but go slightly more duration, which is what the 21 will give you.

Have you looked at VCM's videos on cam selection?

[Toddler78]

So you're going to install headers and then have someone remove them and refit them when they do the Cam install?

Might be easier to ask them to install them as part of the Cam job, shouldn't cost anymore as they're already removing the old parts...

thats if the heads are coming off

[IJ.]

thats if the heads are coming off

Yep keep forgetting about the no lifter cam change butchers...

[RED R8]

going off the dyno graph the 9 would be my pick all day long.....unless its your drag car and you spend a bit of time over 5500rpms.

[Johnn]

Looking at vcm dyno I would also chose the 9
10kw means nothing up there on a street car when the 9 holds 10 over it all the way to 5800
Not to menshion the mass I've 40nm below 3000
As for me fitting full exhaust
The differance is mild 2.5" vs s/s 3" in price if I was to get them to do it all
Everyone I spoke to was 8k drive in drive out with no menshion lifter change or heads off
Also all 3 major shops I spoke to all said use diflippo as for otr I perfor the look of the walky/vcm


Does anyone have input on the 21 v's the 9 would like to see a comparison I asked vcm direct if they had and the one above is what they sent me

[Xjas]

The VCM3 is a lot larger than the 21, I think you'd find the 21 would keep up pretty well with the 9 for torque.
Also worth considering the L92 head (fitted to L98, LS3, L76) are know for being weak flowing on the exhaust side hence most people run split duration cams with them.
The main advantage of the 9 would be a better (less lope) idle rather than extra torque IMHO.

[kangavxss]

I have a VCM9 in my auto VXSS. Low down torque together with my 3.73 diff gears makes for a quickly accelerating car from stand still or from mid range (i have to be careful
not to mash the go fast pedal too hard as the back end always wants to step out). The idle is slightly lumpy only (you can still tell ts cammed) and it drives like standard so no problems. Uses the same amount of fuel
as when it had stock factory cam. Good choice for a daily.