RockyMtC5

I've had my '03 6spd coupe for about a year and love it, but starting to want more power. I have hurricane air intake, long tube headers (not sure which ones), the car is lowered on C6 wheels and Hogkis sway bars. Runs great but this winter it'll be getting a power upgrade, just not sure what.

So, here in Colorado (high elevation) what is a better way to get over 400 RWHP & RWTQ out of this beast?

I'm talking to Trent @ CPU about doing a head/cam package (ported LS6 heads, cam and associated valve-train upgrade). He is suggesting Fast intake and LS2 throttle body conversion also, but I am not sure I need the intake and throttle body to get over 400 hp/tq. I believe I should get there with just Heads & cam & a good tune with my bolt ons currently. I'm guessing this will cost me about $4500-$5K installed, tuned & out-the-door.

I'm also considering going with the A&A or ECS supercharger instead of head/cam. ECS base unit can be had for $4799 and A&A for $5300, so I'm pretty sure installed, tuned and out-the-door for $6K is attainable. So, for just another $1K I should easily be able to hit 500 RWHP/TQ ….. but with 53k miles perhaps a valve train upgrade would be in order also……

I've never cammed or supercharged a car, so this is all new to me. I do have another full bolt on LS that is around 370 RWHP/TQ but that is all stock engine internals also.

For us high elevation guys, what do you think I should do? Head/Cam or Supercharger??

94ltz

I know Trent really well, he just built my 416 stroker.

It depends what your really going after. Do you want the sounds and feel of a heads/cam car or would you rather have the stock like feel but instant power of a blower?

If you do the blower I would go with a bigger head unit just for the fact of most guys decide later on to build a motor and want/need to push the blower a little more.

RockyMtC5

Thanks for the input! I haven't driven a cammed car or supercharged so hard to say which Id like better.....
I'll talk to Trent about it and see what he suggests. I do love the idea of a mild-moderate cam, higher flowing heads and new timing chain, lifters and basically a new top end. But for close to the same cost the sound of 500+ rwhp that kicks in at 3000 rpms sounds like fun! I'd stick with the base 1500 ECS head unit and minimal boost to not push stock internals of my ls1.

I'm a newbie to mods beyond bolt ons so I appreciate the reply!!

94ltz

One thing to also take into account is if you have emissions.

RockyMtC5

I am in Boulder County, so yes on the emissions. Trent asked if I needed to pass emissions, and I said Yes and he said he could still do it. don't we all have to pass emissions here in Colorado?

When I bought the C5 it had no cats & the dealership had them put on so that it would pass emissions and they could sell it to me.

Wouldn't a supercharger be easier to pass emissions with than a head/cam vehicle? If so, there's another strike for going supercharger

Like I said, I'm a newbie in regards to mods beyond simple bolt-ons. I've always wanted to build a forged stroker n/a build and I think I'll do that one day, but just not with this car since I'm starting with smaller cube LS1. I have a Pontiac G8 GT that is my daily driver, and thinking about having a motor built for it but it has 186k miles now so I may just drive it to the ground instead (or trade it in on a 2016 Charger ScatPack)

94ltz

Not all of Colorado has emissions but yes a blower would simpler to pass, all your really doing is adding pressurized air.

I know Trent can design some killer heads and cam combos and still pass, hell my 416 is built for emissions and we are looking for low 500whp N/A.

RockyMtC5

I've heard good things about Trent and CPU, so I'm excited to talk to him and see what we can plan for this winter project!

500whp will be easy with nothing else but a the supercharger so I'm starting to lean this way…….

RockyMtC5

Spoke to Trent today and am meeting him at his shop next Tuesday to go over options and lay down some money on parts to get this power upgrade in motion!

94ltz

Nice, last time I was there he had easy 5-6 vettes along with the normal camaros, trans ams, etc.

petsur

Ask him to fire up his Z06 and have a listen to his cam! Sounds bad ***.

RockyMtC5

I'll have to do that! I am going to ask him to take my C5 for a spin and talk to him about my goals (more power everywhere but not for racing or tracking, so needs to stay easy to drive).
I'm going to ask him about the AFR 205 or 210 heads, I've read a lot about these being the best street head with most low/mid range power like what I'm looking for. Not cheap but hell, I only want to do this once so I want the best heads now. I think I wanna keep my stock LS6 intake and ported throttle body (I don't think I'll need the extra 20 hp or so that a Fast/LS2 package would bring with the superior heads and I can always add these later). A mild-medium cam with under .60 lift and new timing chain, lifters, oil pump, etc. I think I'd be easily over 400 rwhp & rwtq and with very street able manners….. but he's the expert so I will see what he thinks.

Turns out that Tuesday is my birthday so I'll be in an extra good mood when I meet with him ---> I'm going to treat myself to a nice birthday present no matter what

94ltz

Have fun with it man, I just fired up my new 416 stroker and love the sound!

RockyMtC5

Holy crap that is nasty, putting down some serious power I bet

petsur

Sounds hungry! You should think about getting rid of that muffler on the intake and run one from a Z06. Same element.

94ltz

I want a Z06 intake but can't seem to find one for a decent deal considering it's really not going to give me any power gains I don't want to spend a ton on it.

tommypenguin

My vote would be going SC given the altitude. It would for sure hit your power goals and give you head room to go bigger down the line. If my car were running I would offer to give you a drive in it some time. Motor is at the machine shop.

RockyMtC5

I already decided to move forward with Heads and Cam. Trent said he'd get me specs today so I'm anxiously waiting ;-)

I believe supercharger may still be an option down the line, I think we are going to keep compression around the same as stock but completely upgrading the valve train so if/when I do go with a supercharger I'll be pushing some real power! But one thing at a time…..

7LitreC5

I think that is a good choice. I've been down the supercharger path and prefer NA.

Do you have to deal with emissions where you are? If so make sure that you choose a cam that will allow you to pass the test.

RockyMtC5

Yes, emissions is something I have to do so he said the cam he spec 'd for me is emission friendly (224/229 .605/.612 lsa 115 itcl 113).
It's Chinese to me but hoping it gives my C5 a big kick in the ***

RockyMtC5

Update: I went heads and cam with supporting internal parts (new timing chain, oil pump, lifters, trunion upgrade, etc). I've had it since Friday and absolutely love it! Dynod 406 rwhp and sounds AMAZING. WOT is awesome and the cammed idle sound is intoxicating. Drives great around town and screams all the way to 6800rpm. Trent at Colorado Performance Unlimited did an awesome job & fixed my ABS also.
Luckily the weather the last two days allowed me some seat time and I am very happy with the results. Supercharger will have to wait ..... At least until next year