how much HP if I install a SC cam

ignac002 · 10-01-2013, 03:29 AM

Hello,

I Like to install a SC cam in my engine and wondering how many HP I could get after install. them.

Engine is modify:
- Carrera intake
- EFI (SDS ECU)
- OBS headers
- Costum made intercooler (same like GSF are making)
- Open flow exhaust

The heads on the engine are stock. (sigle plug)
stock wastgate (0.8 bar).

The Car is in 2008 convert to EFI by my self and I never went to a Dyno.
But I will do it before changing those cam.

Regards.

T77911S · 10-01-2013, 03:44 AM

4

i love questions like this

RarlyL8 · RarlyL8's Garage

Peak HP increase means little with SC cams, it's all about off boost torque. With EFI added to the mix the engine should be quite responsive. You will pick up a bit extra power on top but that is not the emphasis. You don't say what turbo will be used. For best results the boost range of the turbo should match the power band of the cams.

ignac002 · 10-01-2013, 08:17 AM

I'm running a K27 7200 turbo and maybe in the future I like to install a gt35r.
So RarlyL8 you are say the change in HP is minimal?.

unclebilly · unclebilly's Garage

If you are only looking for horsepower numbers, crank up the boost to 1 bar. You have EFI so if our injectors are big enough, you should be able to get in enough fuel.

TurboKraft · 10-01-2013, 09:01 AM

SC camshafts are a great upgrade. For your engine configuration, peak power will be moderately higher than with 930 cams, but the big gain is the midrange torque and off-boost response. These mean improvements in the drivability of your Turbo.

Those cams also have a lot of max power potential if the engine is developed further. For example, this car has the original SC/Carrera camshafts:
America Roadster Turbo Project

Tippy · 10-01-2013, 09:25 AM

Quote:

If you are only looking for horsepower numbers, crank up the boost to 1 bar. You have EFI so if our injectors are big enough, you should be able to get in enough fuel.

Why not 1.5 or 2 bar?

ignac002 · 10-02-2013, 04:13 AM

Tippy, I would like to keep my engine in one piece, thanks by the way for juot info.

TurboKraft, I understand what jou mean, but with my setup what kind of number (HP) we are talking, 300, 350 400 HP.

But I like to now where I am in HP with my setup after changing the cams.

Thank you all for the answers.

RarlyL8 · RarlyL8's Garage

I would guess your number to be in the 350-370 WHP range with those mods and stock boost. The SC cams might be worth 15 WHP over stock depending on how they are timed. The torque curve is a better indicator.

TurboKraft · 10-02-2013, 09:41 AM

"How much" depends greatly on the efficiency of some of the engine parts (exhaust, intercooler) and your tuning skills.

For comparison's sake, here's results from an ex-ImageAuto 3.3L we tuned up while back with EFI, SC cams, flat manifold, stock heads, B&B header + muffler, UMW K27S, Kokeln intercooler, and 0.8bar stock wastegate. On the Dynapack:
366.8hp @ 5,711rpm / 371.2tq @ 4,675rpm
Customer didn't wish to run any additional boost.
With the boost turned up, it should max out the turbocharger ~395whp (455hp flywheel).

Another 3.3L, not so different than above: EFI, SC cams, flat manifold, 36mm heads, B&B muffler, Hooligan muffler, GT35R, Andial longneck intercooler, 1.05bar boost (stock wastegate spring but boost creep):
464.8hp @ 5,894rpm / 432.1tq @ 5,243psi

Tippy · 10-02-2013, 05:53 PM

Wonder why the owner wished to stop at 0.8 bar?

TurboKraft · 10-03-2013, 08:24 AM

Don't know, didn't make sense to me, either.

Tippy · 10-03-2013, 09:18 AM

Seems to have left a bunch of power on the table.

Tinker · 10-04-2013, 07:31 PM

Chris, Did they two cars you mentioned drive different? Obviously one has greater power, but the peak torque is higher in the rpm range (due to the heads and turbo?). Curious if there is much lag with the GT35R?

Thanks,

Tinker

s5uewf · s5uewf's Garage

how much horsepower increase is typical for every .1 increase in boost, given the usual bolt ons: intercooler, k27, flow through exhaust, tuned AFR levels? Going from .8 to .9 and from .9 to 1 bar, for example?

Is it boost level or timing that gives the most increase, once intake and exhaust restrictions are removed? If the k27 is limited to around 375HP (is it?), is it as simple as increasing boost to get to that level, assuming AFR's are tuned and there is no engine knock? Or is timing more important in getting there? For example, adding water/meth and timing to get there?

It sounds like the cams are not really adding much HP, just moving the powerband around. Is there a cam that actually will had significant HP to a typical set of mods, without requiring piston pocketing, etc.?

911nut · 911nut's Garage

Quote:

Originally Posted by s5uewf

It sounds like the cams are not really adding much HP, just moving the powerband around. Is there a cam that actually will had significant HP to a typical set of mods, without requiring piston pocketing, etc.?

The SC cam has more duration than a stock cam. More duration = more cylinder filling = more hp (approximately 10% more). It's all about mass flow through the engine.

spuggy · 10-05-2013, 05:46 AM

Quote:

Originally Posted by 911nut

The SC cam has more duration than a stock cam. More duration = more cylinder filling = more hp (approximately 10% more). It's all about mass flow through the engine.

10% more seems spot-on to me. My 930/60 dyno'd 330 @ the crank with SC cams, stock intercooler, 3DLZ, RoW headers and a dump pipe. Stock, the 930/60 was rated @ 300HP.

What the SC cams do, as other have said, is really wake the motor up when the turbo isn't blowing; drives like an SC with a big-bore kit until it does.

And they don't hurt when the turbo starts blowing either.

911nut · 911nut's Garage

Quote:

Originally Posted by spuggy

10% more seems spot-on to me. My 930/60 dyno'd 330 @ the crank with SC cams, stock intercooler, 3DLZ, RoW headers and a dump pipe. Stock, the 930/60 was rated @ 300HP.

What the SC cams do, as other have said, is really wake the motor up when the turbo isn't blowing; drives like an SC with a big-bore kit until it does.

And they don't hurt when the turbo starts blowing either.

Good to hear that.
I've installed SC cams in my engine but I'm a week away from having my car back on the road.
Did you have to enrich your mixture?

JFairman · 10-05-2013, 12:20 PM

If you want more HP why waste your money on SC cams. Put in 964 cams instead, the cost done on new billets or a weld and regrind on stock cams is the same.
They have the same 113mm lobe angle seperation as SC cams so they work great with CIS and have smooth idle but they also have more lift and duration than SC cams so you'll have more upper rpm range torque and HP than SC cams.

If you advance the cam timing to 1.3 - 1.35 mm from 1.26mm they have good midrange torque.
SC cams would probably have a little more low and midrange rpm torque than 964cams timed at 1.33mm but I'm not sure of that.
You can also raise compression from 7:1 to 8:1 and run a little lower boost while using pump gas and get more midrange torque.

spuggy · 10-05-2013, 02:32 PM

Quote:

If you want more HP why waste your money on SC cams. Put in 964 cams instead

I don't use 964 cams for the same reason I dont fit RSR cams.

SC cams give MORE TORQUE lower in the rev range and off-boost than 964 cams. (almost exactly the same profile as 3.2 cams, and 993TT cams).

964 cams breathe better and yield give slightly more power than SC cams at higher RPM. They do this by trading off low and mid-range torque.

You (a) don't notice 5HP difference WOT on the top end, (b) can run an extra PSI or so to get that back if you care anyway.

BUT you WILL notice extra throttle response and low/mid-range pickup every time you accelerate off-boost.

So SC cams work really well for a street car. IMHO.