Hi all, first off I'd like to introduce myself to the forum as this will be my first post! I have been looking into getting a over radiator cold air intake, custom dyno tune, but am still unsure about doing the headers and high flow cats due to conflicting opinions by different shops. I have a 2015 Calais V 6.0L, and while I am wrapped with this car, I feel a little disappointed with its low down grunt and throttle response. I would prefer to keep it as quiet as I can from standard, my missus uses it as her daily drive car and I'm getting a bit past the loud exhaust now at my age. I do like it to be quiet when just cruising around. I have had two mates that have highly recommended I take it to Western suburbs mechanical to get them to work on it. I've spoken to drew there and he has suggested to go for a cold air intake and custom dyno tune, with the option of ceramic coated headers and high glow cats, keeping the rest of the exhaust standard. He is saying with all of that I should expect approx 320-340kw at the flywheel or 320-340hp at the wheels, which sounds great if that is an accurate statement. I've also spoken to Chris from hi-torque on the Gold Coast and he actually recommend that if I want more low go down grunt to leave the standard exhaust alone completely, as putting on headers and new hi flow cats I would lose a little down low but get much better gains from mid to top end.. I am hoping to find someone on here that has done something like what I'm thinking about doing at either of these two shops, and what they felt they got out of the mods/tune. The numbers actually don't mean a whole lot to me as I know that they can play with the readouts some to make it look impressive for the customer. I'm more wondering what people have felt once they've done these things and how much more performance and throttle response improvements over leaving it completely standard. I have asked them both the question if we can tune it to run on 98 octane to give it the best chance to get some more out of it, they both say they would do that. So having said all this, would I feel a noticeable difference in throttle response and get up and go with just the intake and custom tune, or will is feel like a wast of money if I don't do the headers and cats at the same time? Particularly looking for people that had their work done at Western suburbs mechanical, since they are saying they spend a considerable amount of time tuning each car to what they believe to be perfect before letting it go home. Any guidance would be appreciated here. This would be as far as I'd go I think with mods to this car, as I plan to upgrade in about 3 years to a new car and don't want to go overboard and potentially make it harder to sell and waste unnecessary money. Thanks guys and sorry for the long post, but I figure the more information I can give, the more you guys can help out. Cheers
Hey mate, I can't speak for either of those shops or tuning the LS3 (ask me in a few months though perhaps , however for what it's worth, I had my old LS1 WH statesman tuned a few years back at Castle Hill Exhaust with pacey Tri-Y's, OTR, and catback (can't remember the bloody brand though..!) it transformed it down low and got rid of that notorious flat spot they had. I get that an LS3 is a long way from an LS1..but the principle remains the same.
Mine has OTR and tune. Standard exhaust apart from marriage savers replacing the mufflers. Quite a noticeable difference in performance from stock, so well worth the money. If you're putting the headers on purely for performance (not sound) I'd be saving the 2 grand it'll probably cost you as you'd be lucky to see another 10kw from the headers
I spoke to a lot of shops, and was intending to tune and OTR, with headers and high flow cats through standard exhaust. They said it will sound stock, but with a bit more growl when planted. I wanted to only tune it once, so have often for REX 4-1 headers and cats, with a manta quiet catback. Will report back in a few weeks on how loud it is compared to marriage savers. Most people have said 240ish RWKW tune and OTR only, 255rwkw adding the headers and cats, and another 10 or so with complete system. Most full system tuned VFs seem to achieve 260-270rwkw
D Mig, what I would do is do the OTR, get a set of secondhand HSV Tri-Y headers, some high flow cats and do your tune. Leave your stock catback. This will give you better bottom end but leave you approx. 10-20rwkw short of those with full exhausts. A great and cheap compromise.
G'day Dr Migg; I had gotten an OTR, HSV headers (retaining the stock exhaust from cat-back) and custom tune done at Streamline Automotive (Beresfield NSW). After the job was done, I felt a noticeable change in throttle response and pick up. The need to add more acceleration climbing grades is no longer needed as an example. The exhaust didn't get louder, just deeper. Hope that helps.
Cheers mate, that gives me some confidence, it's still a very similar motor just more refined from what I can see now. Hopefully I will be just as happy with the changes just as you were with yours :
Good advise! I think that's what I will do first actually, unless I can find some hsv extractors that duaned mentioned below, that sounds like a good idea too!
Thanks for the reply mate, this would be very interesting to see how you find your car after this had been done! Please let me now when you get it done, I'm keen to see what you think! I'm new to this forum but can you tag or message me or something to let me know when you give us all your review on what youre about to do?
I like the sound of this mate, this is really helpful advise, especially to save some money. I will have a hunt around for some, would it matter what year model motor they come off?
It is helpful mate, thanks for your reply. I think I will be looking into finding some of these hsv headers. That's a smart idea. I like it!
They are replacement rear mufflers. They are essentially a straight through pipe, with another piece of pipe welded onto it, in the shape of a J, called a helmholtz chamber that cancels out drone. The marriage savers have a resonator that makes it a tad quieter, and reduces drone a bit more. They sound pretty good, have had them on for 8 months, and are a good compromise for note.
Hi Dr Migg. Western Suburbs Mechanical Tuned my Redline. Service was fantastic. Due to circumstances beyond everyones control, they tuned it while i waited, so i got to see it done. From memory, it probably had about 5 or 6 dyno runs, then they took it for a drive afterwards. So it's done properly. They had a lot of nice cars in there getting done too, so they must be doing something right. Mine has a full x-force exhaust and OTR. One thing that hasn't been mentioned is that they tuned my Auto too. But only the sports mode, they left the standard Drive mode alone. I like the extra power, and it just feels sharper. Even without the full exhaust, after you have it tuned, i'm sure you'll find it's much better to drive. Thats my experience anyway. Hope that helps. Cheers Gus
This is great to hear, I have only heard good things from them now which has given me complete confidence, I was just curious to hear some other reviews of them and they really do sound like they do the job well. Thanks for taking the time to reply. It's been a great help!
