When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
The technician from FVD said with the FVD ECU Tune and Sport Headers will increase power to between 365hp and 370hp.
Has anyone else had a tune and headers installed on a 981S ? Are these claims accurate?
This will bother some, but unbiased people who have dynoed their cars properly know those claims (50-55 bhp on catted headers and tune) aren't reality.
This will bother some, but unbiased people who have dynoed their cars properly know those claims (50-55 bhp on catted headers and tune) aren't reality.
Never mind a 981S, Softronic posted a dyno result on planet-9 showing 370 hp for a 987.2 with headers and tune.
I'd believe 30-40hp gain, but the big gain is to your ears IMO. I have race headers and tune and have seen dynos on here at 330whp or so, which should be ~380bhp. Doesn't really matter anyway unless you did a baseline on the same dyno. Enjoy the headers, best mod for the car IMO.
Never mind a 981S, Softronic posted a dyno result on planet-9 showing 370 hp for a 987.2 with headers and tune.
Smh…..that dyno baselined @ approx. 350hp and those were catless, yours are catted. What I said, and you quoted, is 100% fact.
I'm trying to use my actual dyno time (50+ multiple config runs on the 3.4 alone) and club competition experience to help the less experienced here.
Smh…..that dyno baselined @ approx. 350hp and those were catless, yours are catted. What I said, and you quoted, is 100% fact.
The confirmation bias here makes this pointless. I'm done trying to use my actual dyno time (50+ multiple config runs on the 3.4 alone) and club competition experience to help the less experienced here.
Another useful contributor gone at rennlist.
Hi A432.
Ok, here are some details about my mods, I have purchased the following products from FVD Brombacher;
I am assuming that these 2 FVD mods will give me estimate of between 365 hp to 370 hp.
Additionally i understand from reading other posts that the 981S 3.4 engine in the Boxster is basically the same as the 991 base 3.4 engine.
The only difference is the 981S engine is restricted by Porsche ECU software to 315bhp while in the 991 its unlimited to 350 bhp.
Therefore i am assuming the FVD tune alone will give me 352 hp (see link) and the FVD Sport Headers will provide an additional 16 hp. (also see link)
I think they are pretty reasonable expectations assuming FVD are a respected company in the Porsche tuning industry.
My car is still in at the garage having the Sport Headers installed and will be ready on Monday for collection.
Looking forward to next week.
Last edited by michaelscain; 06-19-2020 at 12:54 PM.
I am assuming that these 2 FVD mods will give me estimate of between 365 hp to 370 hp.
Additionally i understand from reading other posts that the 981S 3.4 engine in the Boxster is basically the same as the 991 base 3.4 engine.
The only difference is the 981S engine is restricted by Porsche ECU software to 315bhp while in the 991 its unlimited to 350 bhp.
Therefore i am assuming the FVD tune alone will give me 352 hp (see link) and the FVD Sport Headers will provide an additional 16 hp. (also see link)
I think they are pretty reasonable expectations assuming FVD are a respected company in the Porsche tuning industry.
My car is still in at the garage having the Sport Headers installed and will be ready on Monday for collection.
This will bother some, but unbiased people who have dynoed their cars properly know those claims (50-55 bhp on catted headers and tune) aren't reality.
One thing you're glossing over is that the first 25 HP to be gained are already "free" because they're artificially missing due to ECU programming. The CGTS has 340 crank vs the Boxster S's 315 with nothing but software. So the actual gains you're talking about are another 25 or so on top of what Porsche programmed out to be gained from better headers and a tune.
360-365 crank is realistic. My CGTS did 371 PS in hot summer weather on a MAHA dyno (the most accurate approximation of crank HP and demonstrably showing spot on figures for Porsche's rated power numbers) with race headers and tune. Cats will sap 5-10 PS so there you go.
Originally Posted by ///M///
I don’t get this.......Any reason why everyone quotes crank numbers and not WHP? Considering a Dyno is being used wheel HP is the number to go with.
For comparison's sake crank power is vastly superior. Wheel power can be influenced by a million different things from tire pressure to tire compound to wheel weight to how strongly they strapped the car onto the rollers. And all manufacturers rate by crank power so you can't even compare WHP to anything.
If you have access to a MAHA dyno, it will spit out the correct crank number even when you play with the abovementioned variables. It will register more or less wheel power but still come to the same conclustion about the crank power. That's why the Porsche factory (and many others) have MAHA's on site.
Hey A432!
Quick question regarding ECU tune.
I have 981S which I’m very pleased with, but if I decided to do a tube what HP numbers would you expect
at the wheels.
Asking more out of interest and general knowledge.
Thanks!
This is not true. For one thing, 911s have better intake design & routing taking cool air from the top instead of from the side, almost acting like a ram-air intake.
Secondly, the throttle body size difference of 74mm vs 82mm on 911s.
I am not talking about 911s?
The Cayman GTS has 340 HP with _identical_ hardware to the 315 HP Boxster S. Only difference is the ECU allows the throttle valve to stay open fully whereas it is restricted to varying degrees on the lower powered 3.4L 981 cars above 5500 rpm.
So the difference between 315 and 340, those 25 HP are free because Porsche artificially removed them.
One thing you're glossing over is that the first 25 HP to be gained are already "free" because they're artificially missing due to ECU programming. The CGTS has 340 crank vs the Boxster S's 315 with nothing but software. So the actual gains you're talking about are another 25 or so on top of what Porsche programmed out to be gained from better headers and a tune.
Originally Posted by A432
I'm done trying to use my actual dyno time (50+ multiple config runs on the 3.4 alone) and club competition experience to help the less experienced here..
Maybe you missed that. About 10 things are glossed over, this wasn't meant to be a technical article. Of course the Porsche torque limiting TP program showed itself.
Like I said, on a 981BoxS, we didn't see a 50-55hp gain on a tune and catted headers. Notice I spoke in gains ie. baselined and normalized relative testing procedures.
There are multiple reasons why that happened, which nobody is mentioning, which leads one to believe people don't want the real answer but some absolute number to boast about.
I didn't claim absolutes for a reason.
Like I said, on a 981BoxS, we didn't see a 50-55hp gain on a tune and catted headers.
Fair enough. Not wanting to step on any toes. But there is a lot of good data from Germany where they've run hundreds of these cars on MAHAs with all kinds of mods. Ehresmann alone has done the tuning on over half of the 3.4 litre race cars on the Nurburgring. The absolute most that can be gotten out of one is 385 PS - catless with larger throttle. 375 on stock throttle catless and about 365 in the sensible "sport headers + X-tips and tune. That is 50 PS over what a BS does stock at the flywheel.
That means 50-55 might be a tad high but not totally outside of reason.
My GTS also raced over 2 seasons before we put the 3.8 in and I have lots of speed trap data between it and my teammate's 981S (Cayman) with other mods and many different tuning maps. The real world corresponds to what we see on the dyno just fine.
Notice I spoke in gains ie. baselined and normalized relative testing procedures.
Lots of guesstimation involved if you're not using a dyno that gets you the right crank number. The invisible losses don't scale linearly so you it's hard to say what the engine is doing exactly and where it makes peak power. On a Dynojet run I picked up 22 HP at the wheels while the same spec had the engine making 31 PS over stock on MAHA...
06-17-2020, 10:00 AM
981S Sport Headers
