Can the Cam?

[EternityDre]

I brought this discussion on my pending MSE upgrade from the "Are HSV 325 headers an upgrade" to back here. Apologies for that.
So I called Gentech this morning. DPE Walky system is available. They will fit this and tune for $5,900. Tune would be more aggressive than the W375 pack, which they said was very conservative. But still a very safe tune. They said they don't recommend chasing every last peak KW, which is good. So TQ everywhere under the curve should be better than W375. Just no supposed Walkarranty. Alterntively, they will fit the 340 headers, high flow cats and tune for $1,440. They said the main issue is the shitty cats and they can fit good high flow cats with a good entry angle. So, it's DPE with no Walky warranty, or modded HSV for $4,460 less. That's a fair bit of coin! So I expect the DPE path will gain more peak KW. Maybe 385? But, the HSV Tri-Y's with modded cat entry and high flow cats may be a bit better in bottom end TQ and not say 365/370. As I said before, I can't see the value for such a small net gain. Yes the DPE sounds great. But so does my Redline with the HSV bits and HF cats. With the money I save, I can add a can down the track... You're probably all sick of hearing my muses. But, that's where I'm at. It's a simple cost benefit decision now.

If you're happy with the HSV option go for it and save the dollars. Just be aware with DPE closing, it will be a lot harder (if at all possible) to get later if you change your mind. $5,900 is steep.. I paid $4,800 for my 385 pack.

 

[Happydaze]

Back in Jan 2018, I installed the followings to my VF2 redline ute:
- VCM 523 cam which came with HD valve springs, APR crank/cam bolts, oil pump.
- X force full exhaust with 1 7/8 header, duel 3" system with Varex rear mufflers.
- VCM OTR kit with infill panels.

After one year driving
Likes:
- Terrific exhaust noise.
- Midrange acceleration.

Dislikes:
- Not so smooth idling.
- Not so smooth gear changes.
- Engine stalled occasionally at cold start.
- Tunned many times to get it right.

Personal Conclusions:
- 2.5" exhaust system probably better.
- Probably shouldn't have installed the cam.

Sounds more like poor tuning.

224 230 114 in my E1 retains almost factory manners. Nice bit of lump, good power gain, doesn’t push. Boost friendly if that path is taken later.
Had a slight issue when cold, it would start fine but needed to warm up a few minutes before driving off.
Quick call to the shop to confirm “that’s not normal”. Left it over night so they could cold start it and touch up the tune. Good as gold.
My first aftermarket cam in a LS motor, 18000 k’s in, got to say I’m very happy with it, and would do it again.

 

[PeteSS]

I brought this discussion on my pending MSE upgrade from the "Are HSV 325 headers an upgrade" to back here. Apologies for that.
So I called Gentech this morning. DPE Walky system is available. They will fit this and tune for $5,900. Tune would be more aggressive than the W375 pack, which they said was very conservative. But still a very safe tune. They said they don't recommend chasing every last peak KW, which is good. So TQ everywhere under the curve should be better than W375. Just no supposed Walkarranty. Alternatively, they will fit the 340 headers, high flow cats and tune for $1,440. They said the main issue is the shitty cats and they can fit good high flow cats with a good entry angle. So, it's DPE with no Walky warranty, or modded HSV for $4,460 less. That's a fair bit of coin! So I expect the DPE path will gain more peak KW. Maybe 385? But, the HSV Tri-Y's with modded cat entry and high flow cats may be a bit better in bottom end TQ and not say 365/370. As I said before, I can't see the value for such a small net gain. Yes the DPE sounds great. But so does my Redline with the HSV bits and HF cats. With the money I save, I can add a can down the track... You're probably all sick of hearing my muses. But, that's where I'm at. It's a simple cost benefit decision now.

To me it's a no brainer. i would go the HSV system with a tune. When you look at the packs offered (Harrop/tekno, etc), the gain offered by headers, cats + catback is around 25kw (flywheel) on top of just an OTR. Even if the HSV headers + cats gives you half of that gain, i can't justify the extra money for a DPE system for the minuscule power gain

 

[rognvald261]

My preference would be to carefully and thoughtfully enhance the core motorsport aspect of the car, and because it is a limited edition I would step up to something still GM. That makes it easy to explain and low risk for future buyer or any tyre kickers really. Take a close look at the LSX376-B15 race engine, simply a low-CR LS3 that uses LS7 cam with high ratio rockers, better springs. It is rated at 353 kw.

 

[426Cuda]

As I've said before, I really do appreciate everyone's input and tolerance of my musings. My mind is made up. I will sacrifice a few top end KW's and save $4.5 large. If I decide to cam it up down the track, I'll fork out for a full aftermarket system then. I'll be at worst $1440 worse off, ignoring time value of $.

 

[426Cuda]

To me it's a no brainer. i would go the HSV system with a tune. When you look at the packs offered (Harrop/tekno, etc), the gain offered by headers, cats + catback is around 25kw (flywheel) on top of just an OTR. Even if the HSV headers + cats gives you half of that gain, i can't justify the extra money for a DPE system for the minuscule power gain

Well, it worked on my Redline for torque, power and sound. So why not the mighty LS3!

 

[07GTS]

As I've said before, I really do appreciate everyone's input and tolerance of my musings. My mind is made up. I will sacrifice a few top end KW's and save $4.5 large. If I decide to cam it up down the track, I'll fork out for a full aftermarket system then. I'll be at worst $1440 worse off, ignoring time value of $.

if u want power and keep the exhaust just put a blower on it then size dosnt matter it'll just force it out

 

[lmoengnr]

Well, it worked on my Redline for torque, power and sound. So why not the mighty LS3!

I worked out the HSV headers and cats were pretty restrictive on the Maloo, when they were replaced by decent headers and cats.
They 'unlocked' a shedload of torque all the way through the rev range, and that was before the tune.
Took 4 days of driving before the CEL came on...

 

[abuch47]

I worked out the HSV headers and cats were pretty restrictive on the Maloo, when they were replaced by decent headers and cats.
They 'unlocked' a shedload of torque all the way through the rev range, and that was before the tune.
Took 4 days of driving before the CEL came on...

Nice. How likely is it that changing just the cats in the hsv system will through a CEL?

 

[vr304]

Nice. How likely is it that changing just the cats in the hsv system will through a CEL?

The rear o2 sensors measure the efficiency of the cats so if you fit hi flows they will trip the check engine light and the solution is to get the rear o2 sensors turned off in the tune