My feedback - Upgrading from mild to large camshaft in Auto L98

[GTS_365]

My car is a VE SSV Auto with a 4500rpm stall converter, otr, exhaust, 3.45 gears.
Recently upgraded from a mild 220/220 .595 lift 113 LSA to a 238/242 .603 lift 112 LSA.

I wish I did this sooner, or better still right from day 1 instead of wasting my time with a little cam.
Who said big cams only make big power after 5000rpm? The new cam shows improvement everywhere especially down low (refer attached graph).

On the road the drive ability is identical to the smaller cam, not once has it stalled, hunted, surged. Very carpark friendly and would definitely recommend as a daily driver if you're prepared to pay the extra fuel cost compared to a small cam. It idles comfortably at 875rpm.

The sound is different. Has a deeper louder rumble with much more lope. Sounds like a v8 should.

Overall, the new cam works great with a high stall over 4000rpm (which are made nice and tight these days) and picked up 33rwkw over the smaller cam with a big increase of torque down low. L98's respond well to big cams, very smooth to drive with a big punch when pushed. My previous 1/4 mile time was 12.01, hopefully should go mid 11's now.

I cant speak for manual vehicles, but those who have an auto, do not hesitate to buy a big/stall cam combo if drive ability is your worry.

VE graph.jpg

[whitels1ss]

Looks good mate,

did you have the stallie in there for the first dyno run with your old cam?

[Micks]

That's a nice result & enjoy!

[GTS_365]

Whitels1ss, yes only change was the cam, nothing else.

[whitels1ss]

Whitels1ss, yes only change was the cam, nothing else.

That is fantastic mate

[white lie]

It looks more like the converter was unlocked on the big cam run and locked for the 220 cam.

Good result though, I like hearing when people are pleased with big cams, stalls etc. A lot of people say they'll be pigs or no good for the street/daily use but generally those people either haven't driven one or have a terribly mismatched combo

[GTS_365]

Hmm better find out. Does that mean the 220 cam would have made less power and the 33kw gain is even greater ? If so why would the tuner do that? Wouldn't he want to show the customer the largest kw gain possible ?

[white lie]

The very top end will be similar but the converter will make a lot more torque down low if it's unlocked. It will be multiplying the torque going thru it if it's unlocked.

Here's a couple of mine for comparison. Run on the same day, within an hour of each other actually. Red unlocked and green locked. No mods, maybe just a minor tweak of the tune. 4500 converter, probably stalls up around 5000 though



Notice how the torque peaks a lot earlier when it's unlocked and then tapers down where when it's locked, it takes a lot longer to build/climb. This is because the converter can do what it's designed to do

In the case of your runs, if it was locked on the bigger cam run, it would make a lot less low down (may be equal to the smaller cam) and then over take the original graph when the cam really starts to come in to its power band.

[GTS_365]

Fair enough yes I understand how converters work that's why it's always one of the firsts mods I do in a V8.
I can confirm the before run was definitely unlocked. To be honest I can really feel that down low difference on the road.

[white lie]

It's pretty uncommon for them to run then unlocked. Most tuners prefer to run big stalls locked as they're more predictable on the rollers.

But when it's run locked, it will look a lot lower on the graph but still perform strong on the street when the converter is allowed to work.