Rowland84

Whats the power difference between the stage 3 and stage 4 btr cams trying to decide which one to go with on my ls2 gto has a m6 with longtube headers 1 3/4 and catless mids and slp loudmouth 1 catback. I understand you will sacrifice some torque on the 4 over the 3 down low but its still got to be better then the stock ls2 cams torque? Just not wanting to regret not getting the 4 over the 3!

G Atsma

Depends on the engine you're putting it in. Too many variables.

Double06

Also you need to factor in tunability and the dreaded low speed / parking lot cam surge that can be very annoying you get with a cam that is too big. The cam surge is mainly with a stick car where there is no driveline cushion.

joyridin'

iTrader: (1)

The biggest issue for you is probably not horsepower, but where the torque and horsepower come in. You do not mention changing the rear end gears, so unless you want to be running around in 2nd and 3rd gear to keep the RPM's near the higher limits, you may be better off with the milder cam.
I had a BTR 4 in my car (not a GTO). I loved the cam. It came on around 3500 RPM and pulled to 7k. I have 3.70 rear gears and a T56 from a 2006 GTO.

Bob570

If you're going to change to a more aggressive rear end and you're not afraid to rev over 7000 rpm, then the stage 4 wouldn't be bad, if you're sticking with stock gears go stage 3.
Really if you're not willing to rev to 7000 then get a smaller cam.

KW Baraka

iTrader: (7)

There's no sure-fire way to know, as a first timer or novice, what type of cam is best for you.

Generally, no one gets exactly what they want the first time around UNLESS they have a frame-of-reference. That is; they know someone with a setup that's close to or exactly what they want.

That much having be said, it's best to err on the side of caution....and go smaller (versus larger) with the cam.

KW

Darth_V8r

iTrader: (4)

Yeah. In general I would err on the smaller side unless it's a track only application. A slightly small cam is torquey and has great midrange while leaving 5 hp up top on the table. A cam that is slightly too big becomes a PITA quickly

LilJayV10

iTrader: (39)

Very well said.

Regardless of what cam you go with, you need supporting mods for it to work efficiently. Compression, gears, stall, etc.

Yeah a stage 4 cam may make 10hp at peak, but under the curve power is **** and it's a PITA to drive on the street.

QwkTrip

iTrader: (23)

I've had two different 427 engines with cams in the Stage 3.5 range. Neither engine lacks torque. I can out pull any LS1 up a hill in 6th gear at 1600 rpm. But that can't describe the lack of civility in 1st gear at 1600 rpm.

Neither engine likes to be much below 20 mph. Once on the move it drives fine. I just have to drive more aggressive off the line than the Average Joe to keep the engine happy.

And therein lies the problem. You see, there are a lot of Average Joe's on the road. And what's even worse is Slow Toyota Joe. My cam and clutch cause me to move at a different cadence than other cars in traffic. It's not a huge deal as long as I have a couple car lengths between us. But if it's a slow moving line with people creeping on their brakes.... then it's hell on my clutch.

So I'd say if you do a lot of rural driving then you'll not mind a Stage 4 cam. If you do a lot of city driving then it can become a real PIA.

Darth_V8r

iTrader: (4)

Partly that is because a 427 makes torque even if by accident. I can pull uphill 20 mph in fourth gear and have surprised quite a few people by doing just that. And that was with the 248/255 cam I just pulled.

You hit on something too. A really hopped up manual really needs to just launch in order to drive decent. And nobody else on the road knows which pedal makes the car go.

wannafbody

iTrader: (2)

With my Stage 2 cam and a M6 the car is pretty easy to drive but I wouldn't want to drive it in heavy city stop and go traffic.

xBoostx

Stage 4 and 4.11 diff gears will give the clutch a brake and makes easy to drive in slow traffic and if it pulled well before you’ll see now.

joyridin'

iTrader: (1)

Seems like a bit too much gear IMHO. The M12 in the GTO has different 1-3 gearing than an M6 due tot he weight of the car. You would be shifting out of 1st at 5-10 MPH in normal city driving. I have 3.70 gears and it is even a bit much with a M12.

wannafbody

iTrader: (2)

It isn't just about duration but also overlap. The stage 2 has 4 degrees of overlap, the stage 3 has 11 degrees and the stage 4 has 16.5. In talking to people as the overlap increases the car becomes less streetable at low rpm.