I think the issue with dynos is the variations of the baseline. I can remember an article discussing 3 different stock cars with HP varying by as much as 12 under the same test. I think that this is no longer the case but I could see that a tuner would be cautious. I thought that RSC posted a dyno of 443 or 446 with their entire package. I never had mine dynoed but I can be certain in that my car felt much faster and my AM tech said the same thing.

 

Paramount had a dyno showing 448 hp, but it was odd because it showed a dyno graph but showed the 448 hp as crank horsepower, not at the wheels. There's no graph showing baseline WHP and then post tuning change. I do think the tuning from RSC etc works, but for some reason no one has ever come up with a good dyno graph to show it.

 

Tahoe-

My point exactly. I am also sure that RSC offers fine products, enough so that I plan on purchasing, based on other users experiences. I would just like to know how much benefit there is at the wheel from RSC and others, for packages and components alike.

I have yet to see any evidence from anyone on the 4.7L gains.

 

I dynoed my 4.3 with RSC remap, K&N filters, and RSC sport cats a while back and the rwhp came out at, I think, 331 at the limit. I didn't have the foresight to do a pre-mod run, but I seem to recall someone dynoing the stock car and coming up with something like 305 rwhp (Tahoe?). However, I have heard that the power can vary significantly from car to car for the Vantage.

FWIW I doubt the Paramount claims.

 

Yeah that's about right...mine posted 307 rwhp stock on a dynojet.

 

Yes, that's what it was. 307. Thanks.

 

So based on that logic, a gain of approx. 10% or roughly 38-40 Hp before loss could be extrapolated. So it is probably safe to say that RSC cars are running about 420-425. I think that is reasonable and frankly worth the price. I know that Mike996tt is running that set up plus the AM manifold changes. I wonder if he is achieving another 10-20 HP.

 

It certainly would justify the price for me.

I think that it is probably reasonable to assume that the addition of RSC green filters, cats and exhaust would add the same rwhp gain, per component, to a 4.7L. The unknown is then what an ECU remap would add. I am guessing that it would not add the same percentage of gain on the 4.7 as it does on the 4.3, and that the increase in general increased engine efficiency and and overall smoothing of the powerband would be the justification for the ECU remap. Stuart??

 

Not sure what the remap alone does but using the 307 and 331 numbers, the total increase for the remap, filters, and cats is 24 rwhp. Stewart has mentioned a few times that the cats alone are worth about 20 hp (not sure if that's bhp or rwhp) because they tested a car before and after the sport cats were put on. This would suggest that the remap and filters do not contribute all that much. However, the 307 was recorded for a different car on a different dyno on a different day than the 331 so these numbers cannot really be relied upon.

It would be great if someone out there would do each of these mods in stages taking dynos along the way over a relatively short period of time to minimize variation due to climatic changes, etc. Until someone does though, we can only guess as to the actual benefit of the mods.

 

The cats are probably IRO 15-20BHP at the flywheel. As far as baseline figures go I have seen RWHP dynos on bone stock cars that range from 292 up to 302, although 307 sounds sensible just depends on the car/dyno/conditions.

 

i don't think the car above had the full catback though, so it would be reasonable to assume that this would add another 5 hp. So we're looking at a car that should match the 09, but perhaps not through the mid/low range.

 

Mmmm.... I don't know that a full cat-back makes much difference. You're only talking about replacing a few feet of mild steel pipe from the cats to the rear box with a different piece of stainless pipe. We didn't bother with that section because it really wasn't going to make any difference to sound, weight or power and we didn't want to be selling something that didn't offer value.

However, I do know that a modded 4.3 will match a 4.7 in a straight drag (although you're right, there's still more mid-range on the 4.7)

 

Stuart, is the mid-range availability on the existing 4.7 produced by the ECU remap? Assuming all else is the same (cats, green cans, exhaust) what do you anticipate being the ECU upgrade in rwhp?

 

One of the reasons we're very hesitant to peg absolute numbers is because dynos (as we all know) are tools which are good for measuring differences, changes, as opposed to absolute numbers. People who I have spoken to or corresponded with will know that we will usually offer a fair estimate with a high number and a low number. I know Paramount produced a dyno with 448.4 BHP with our power pack but that the baseline run for that car was 387 BHP. We also found those results not to be repeatable. On a 4.3 with our full kit I would be very comfortable quoting 425-435 BHP as a typical result.... however.... the reason we're hesitant to really get into hard numbers is because (and this has happened before) that most frequently, someone will do a post-mod dyno only, and then come back saying that they don't understand why they didn't get a higher number. I actually had someone recently who was disappointed with the WHP number until we actually managed to dig up the baseline dyno which turned out to be 292WHP, which was 12-14WHP lower than we thought it would have been....

I will always refer interested parties to our past customers, or this forum because without wanting to sound arrogant, we have a solid customer list of owners who are happy with their results and who feel that they represent good value for money. To my mind that's the most important endorsment I can offer.

 

Sorry Rick, I'm not sure I understand what you mean ref: your tech?