Low HP readings

Author
Discussion

mfp4073

Original Poster:

1,984 posts

181 months

Thursday 30th May 2019
quotequote all
My brother has a 2016 S550 with a V8 and a 6 speed manual. From the factory these are about 415 HP.
The car has a full performance exhaust, headers, sport cats and a cat back system. The intake is a Roush cold air kit, and it had a remap by Wortec.
On a rolling road it only made 428 HP, and put down 360 HP at the rear wheels.
This seems pretty poor as we were expecting about 470 HP at the flywheel, however the car feels way more than the figures suggest.
Do any of you guys have a similar set up with better HP numbers?

Regards John

Garvin

5,265 posts

184 months

Thursday 30th May 2019
quotequote all
The stock headers on a UK S550 Mustang are woeful, particularly on the right hand bank where they had to redesign them to accommodate the steering column for RHD! Just a decent set of headers alone should produce the HP seen!

eybic

9,212 posts

181 months

Thursday 30th May 2019
quotequote all
How "true" is the rolling road? My understanding is that they are pretty much all different, the only way to get a true comparison is against a similar car running on the same road on the same day.

slowhand99

242 posts

115 months

Friday 31st May 2019
quotequote all
How did the torque figures compare? That’s more likely what you can feel on the road.

irocfan

42,391 posts

197 months

Friday 31st May 2019
quotequote all
mfp4073 said:
My brother has a 2016 S550 with a V8 and a 6 speed manual. From the factory these are about 415 HP.
The car has a full performance exhaust, headers, sport cats and a cat back system. The intake is a Roush cold air kit, and it had a remap by Wortec.
On a rolling road it only made 428 HP, and put down 360 HP at the rear wheels.
This seems pretty poor as we were expecting about 470 HP at the flywheel, however the car feels way more than the figures suggest.
Do any of you guys have a similar set up with better HP numbers?

Regards John
Sounds similar to my Camaro - both in terms of what's been done and (seeming) lack of extra power figures. That being said it feels quite sprightly so who cares (easy for me to say since it was a previous owner did the work!)

mfp4073

Original Poster:

1,984 posts

181 months

Friday 31st May 2019
quotequote all
slowhand99 said:
How did the torque figures compare? That’s more likely what you can feel on the road.
The standard torque figure was 530 and increased to 541lb/ft so not a great increase.
The thing is the car feels very strong on the road and has instant pick up in any gear.
We might try another rolling road later in the year.

Matt Harper

6,769 posts

208 months

Friday 31st May 2019
quotequote all
A dynamometer (rolling road) only measures wheel horsepower - so establishing engine hp is a very approximate calculation of driveline losses which tend to be notoriously inaccurate.

What this does demonstrate is the bolted-on plastic tubes with big cone filters, most after-market flash tunes and cat-back exhausts (all loved by so many modifiers) do not produce the hp gains that their huckster manufacturers claim.

I've had a few barnies with folks on here (mostly Mustang owners/fans, interestingly) who's hp claims are quite laughable given the mods done.

I'm not anti-Mustang - I really enjoyed mine, but the mods I made (AirRaid cold air, Bama tune, bigger throttle body and cat-back) combined - added about 25whp. I eventually caved and added a Boss 302 intake that put on another 15-16hp, but also cost me in torque - so something of a wash, in real terms.

LuS1fer

41,750 posts

252 months

Friday 31st May 2019
quotequote all
Rolling roads are not very accurate at all. I have seen some readings which far exceeded the manufacturer's figures and many are plain nonsense. One reason I have never bothered putting my car on a rolling road.
Drivetrain losses can vary but will be 30-40hp.
Ultimately, I take the view that if the car feels fast then it is fast and I don't need to indulge in a totally meaningless bar room bullsh*t contest about who has the most horses.
Anyone that worried will simply take the car to the drag strip to get their quarter mile time. There's no BS involved in that, it is what it is and, as motoring shows have shown us so many times, what makes a car fast is traction and gearing, not just horsepower.

Modifications add sweet FA.
I used to have a 4th gen Camaro Z28 and took it to the strip and ran a 13.8xxxxx. I then modified the suspension, put a bigger air intake on it, put a free flow exhaust on it, lowered it a little, put better tyres on and I gained about 1000th of a second over the quarter mile, albeit with a slightly higher terminal speed (which counts for nothing really).

Bearintown

64 posts

124 months

Friday 31st May 2019
quotequote all
Had CAI and canned tune on a s197 and novelty wore off after a day.
Had CAI and a custom tune from a respected tuner in the US on a Challenger and I thought the gains were even less- others were raving about the gains tho!
Only big difference I had was on a supercharged s197- smaller blower pulley and accompanying tune- now that made a difference! Lost the snap crackle and pop from the exhaust tho!

CraigJ

603 posts

212 months

Tuesday 4th June 2019
quotequote all
Unless he had it dyno’d before the mods on the same dyno the results won’t mean anything as you have no base line. Every dyno will read different too.

Had he dyno’d it first it may have put out 400bhp for arguments sake then the mods would look good but he won’t know now.

I’d go for a 2018 intake manifold with MMR lock outs and a good tune from the likes of Lund or Palm beach dyno and see around or just over 500bhp combined with why he has already done.

mfp4073

Original Poster:

1,984 posts

181 months

Wednesday 5th June 2019
quotequote all
CraigJ said:
Unless he had it dyno’d before the mods on the same dyno the results won’t mean anything as you have no base line. Every dyno will read different too.

Had he dyno’d it first it may have put out 400bhp for arguments sake then the mods would look good but he won’t know now.

I’d go for a 2018 intake manifold with MMR lock outs and a good tune from the likes of Lund or Palm beach dyno and see around or just over 500bhp combined with why he has already done.
Strange you should mention the intake manifold mod as he was talking about that the other day. I've told him to leave well alone as the car is fantastic to drive as it is.
I'm sure the Mustang would leave my Monaro in its dust in any case, but brothers never seem to listen do they!!!

B3NNL

1,056 posts

175 months

Thursday 6th June 2019
quotequote all
I had a dyno done after adding a cat back system, CAI and a canned tune. As yourself I was thinking start point of 415 so should be at least close to 440. We struggled to achieve 401 and that was only be returning the car to stock tune and keeping the CAI.
I then added ARH headers with sports cats and a 2018 Inlet manifold.
The car was then put on a Hub dyno up North and a bespoke tune carried out by Motorsport and Performance which resulted in 430WHP approx 495bhp.
I've since replaced the exhaust which was somewhat restrictive with a 3" Steeda cat back system and should be well over the magic 500 mark. Car drives amazingly and even gave the TVR boys a run for their money on our long weekend away last month which was a good marker as the car was standard last year and it never really troubled them, this year they all agreed that they couldn't pull away on me any more.

mfp4073

Original Poster:

1,984 posts

181 months

Thursday 6th June 2019
quotequote all
B3NNL said:
I had a dyno done after adding a cat back system, CAI and a canned tune. As yourself I was thinking start point of 415 so should be at least close to 440. We struggled to achieve 401 and that was only be returning the car to stock tune and keeping the CAI.
I then added ARH headers with sports cats and a 2018 Inlet manifold.
The car was then put on a Hub dyno up North and a bespoke tune carried out by Motorsport and Performance which resulted in 430WHP approx 495bhp.
I've since replaced the exhaust which was somewhat restrictive with a 3" Steeda cat back system and should be well over the magic 500 mark. Car drives amazingly and even gave the TVR boys a run for their money on our long weekend away last month which was a good marker as the car was standard last year and it never really troubled them, this year they all agreed that they couldn't pull away on me any more.
Thanks B3NNL,

Thats a very impressive result, I'll pass the info on.

Centurion07

10,395 posts

254 months

Friday 7th June 2019
quotequote all
I have a PMAS intake with a Lund tune & catback exhaust system.

The PMAS intake alone added 10/11bhp and identically-specced cars have been dynoed at 470bhp. Despite some people trying to claim such gains are impossible.

CraigJ

603 posts

212 months

Saturday 8th June 2019
quotequote all
Worth having a look at JW racing and there power pack upgrades.

I know a few on Mustang6G have the 510 upgrade and have dyno'd and seen the numbers claimed.

https://j-w-racing.co.uk/section.php/5264/1/2015__...

questmotorsport

2 posts

142 months

Tuesday 23rd July 2019
quotequote all
This is always a topic for debate , some dyno,s read different to others , some dynos are downright rubbish depending on what you are using it for.
My dyno is a tool , a very expensive tool . For mapping it is spot on as the brake control is brilliant , it has reputability test on test , so you can see the smallest improvement , essential for dialling in an ignition map etc.

So what does a dyno measure , it measures load at the wheels or torque at the roller via a load cell , HP {pub figures} are calculated from this TQ reading via a clever math calculation.
Strapping is also essential to stop wheel slip , when testing we monitior approx 100 perameters from engine speed to roller speed , sampling rate , AIT , ECT , Boost / vacuum , Fuel pressure, Lambda plus a whole host of internal channels , we also on later cars take direct from the OBD port all essential data , how many dynos have you seen do this ?
Manufacturers test their engines on an engine dyno and use a SAE std correction factor which are a bit tongue in cheek , did carol Shelby say HP sells cars TQ wins races.. and that was in relation to Fords i believe.
So its not unusual for a car to make less power than stated .

We recently had a Mustang 2107 model S550 in , it had a CAI , X piece rear box delete and it made 365hp , i cant remember tq , it was running horrendously rich over the mid to higher RPM range which is std , they all do it from factory.
WE remapped it in house , optimised the fuelling , opened up PE to work when we wanted it to turned off a lot of unwanted crap and ran it again on the rollers , we gained approx 40bhp and tq , nowhere near Fords claims but the client rang me a couple of hours later and said it is a different animal , st off a shiney stick i think he said.

So back to the dyno , all are different as are the operators , cooling fans are another cause for concern , in 4th gear the 5.0 S550 does way in excess of the legal limit , so if for instance if it does 140 mph using a fan that blows at 40mph is not a lot of good , my dyno is rated at 155 mph with a 10% safety margin , my fan blows at give or take the same speed and pressure , essential for steady state mapping at what ever speed is needed and also to keep the engine bay temps down.

In essence dynos are Data acquisition tools not BS generators .

Cheers Keith


irocfan

42,391 posts

197 months

Wednesday 24th July 2019
quotequote all
questmotorsport said:
This is always a topic for debate , some dyno,s read different to others , some dynos are downright rubbish depending on what you are using it for.
My dyno is a tool , a very expensive tool . For mapping it is spot on as the brake control is brilliant , it has reputability test on test , so you can see the smallest improvement , essential for dialling in an ignition map etc.

So what does a dyno measure , it measures load at the wheels or torque at the roller via a load cell , HP {pub figures} are calculated from this TQ reading via a clever math calculation.
Strapping is also essential to stop wheel slip , when testing we monitior approx 100 perameters from engine speed to roller speed , sampling rate , AIT , ECT , Boost / vacuum , Fuel pressure, Lambda plus a whole host of internal channels , we also on later cars take direct from the OBD port all essential data , how many dynos have you seen do this ?
Manufacturers test their engines on an engine dyno and use a SAE std correction factor which are a bit tongue in cheek , did carol Shelby say HP sells cars TQ wins races.. and that was in relation to Fords i believe.
So its not unusual for a car to make less power than stated .

We recently had a Mustang 2107 model S550 in , it had a CAI , X piece rear box delete and it made 365hp , i cant remember tq , it was running horrendously rich over the mid to higher RPM range which is std , they all do it from factory.
WE remapped it in house , optimised the fuelling , opened up PE to work when we wanted it to turned off a lot of unwanted crap and ran it again on the rollers , we gained approx 40bhp and tq , nowhere near Fords claims but the client rang me a couple of hours later and said it is a different animal , st off a shiney stick i think he said.

So back to the dyno , all are different as are the operators , cooling fans are another cause for concern , in 4th gear the 5.0 S550 does way in excess of the legal limit , so if for instance if it does 140 mph using a fan that blows at 40mph is not a lot of good , my dyno is rated at 155 mph with a 10% safety margin , my fan blows at give or take the same speed and pressure , essential for steady state mapping at what ever speed is needed and also to keep the engine bay temps down.

In essence dynos are Data acquisition tools not BS generators .

Cheers Keith
fantastic and informative post thumbup

davidmitch10

1 posts

45 months

Friday 26th February 2021
quotequote all
The most common cause of power loss is incorrect gasoline. Therefore, to achieve passport characteristics from the car, it is necessary to use the gasoline that is listed in the user's manual. A fuel pump and a dirty filter can also greatly affect the dynamics of the car. The pump is sometimes clogged with dirt or foreign matter. The most radical reason for the reduction in the power of the power unit lies in mechanical damage. In general, all these malfunctions can be eliminated through serious repairs. On this site, poweretty.com, you can see the horsepower of different car models when they are released from the factory.

Edited by davidmitch10 on Friday 26th March 21:06

C350Akra

12,287 posts

287 months

Sunday 28th February 2021
quotequote all
davidmitch10 said:
My E63s shows me the data on KW, how can I change this to HP?
1 kW = 1.341 HP, 1 HP = 0.746 kW