Hi guys.

Just need some opinions on the GSC S2 ~ 274/274 cams.

I plan on putting these into my Evo 6 that has a stock turbo and stock engine/internals.

I understand that there are many factors for an engine that is 16 years old concerning the condition and performance but what I want to know is how much can the stock internals support (Horsepower/Torque), and how 'safe' these cams will go in my stock engine with upgraded GSC springs, retainers, valve seals and valves.

Car is currently tuned on 98 RON,
3" s/s Turboback exhaust
Grimspeed 3 port boost solenoid

DYNO
285awhp, 405nm @ 23 psi

 

Well, as you probably know, we don't have the VI here stateside so probably won't get too much help. I'd say it would handle the cams no problem, with a tune obviously. I had a IV when I was in Okinawa, and always heard the V and VI engines were better designed, so I'd imagine you could handle near 400 tq similiar to the VIII here stateside with a stock block.

 

From everything I've read on lancer registery from the Aussie and UK guys, the V/VI motors are good for around 400whp with a stock motor. If you plan on doing the whole GSC valve train, you're not going to run into any problems with your cams. Even at the 274 duration. I only advise that running such a high duration is going to move your powerband to the right. You'll have more top end by revving higher and carrying the power longer, but you're also going to lose your responce a little bit. If you had something like a bw 7670, fp black, or 35r, those cams would match up far better to where your turbo would be building power. Our smaller factory turbo's spool up amazingly though and that would be a hard pill to swallow having a slower spool and not having the benefits of big power.

Maybe someone with some first hand experience can chim in here.

I have a Evo 5 running 20.5psi tapering off to 18.8psi and I make 295whp with 92 oct, turboback exhaust, aem 320lph and a tune.

 

Evo vi motor is same as evo 7/8 motor
Minor changes have no functional effect to reliability or power.

Mine is at 395whp on Mustang quiet happily.
For many years.

S2 cams will work fine but are lumpy at idle.
HKS 274/278 are smooth at idle.
I have both...speaking from experience

 

Ok, I am fairly satisfied with the internals handling this upgrade (GSC S2 cams) thanks heaps guys

I am after that rough idle because I love it every time I hear it and of course the performance gains although I am aware that it will be pushing the flow limit of the turbo/wastegate lol.

Now I've had a few mates of mine say to me you might need to upgrade your injectors along with this upgraded cam?
I'm sure if it comes to it, a set of 750cc injectors wouldn't cost much and should do the job nicely?

 

Yes, 750's would be fine. Your stock injectors will be in the 90% duty cycle range when you start getting toward the mid 300's. Say 330-340whp. 750's will give you far more room to keep climbing. Depending on what your future goals are, you could also jump to 850's or 1000's and scale them down with your tune. Which is going to be required if you change your injectors anyway.

 

Upgraded valve springs are highly recommended.

EDIT: Oops, I see that you are. Good boy.

 

750cc injectors, gsc beehive springs and retainers, new valves + seals i will post again once this has all been finished, cheers everyone

 

Anyone from perth western australia here? I need the s1 cams instead of the s2's. Brand new just need to switch

 

Hey man I'm in Perth did you want to sell your cams the s2 I do have some Bc272 comming that are milder with less lift but I wouldn't mind more aggressive cams I'm in Perth 0422321845