Power figure & Dyno problems

[Tom5190]

Did a power run tonight on a pretty new rolling road.....

I ran it in 4th gear, went through the test properlly and did 4 runs

138.6bhp
141.2bhp
142.8bhp

Is a J4 with hardly any mods tbh, i rekon its actually putting out more like 115-120.

The diff bearings are pretty shagged a new g/box is going in next week, before some catcams are bungged in, just want a second opinion on the RR i used really. I know it will over read with the faults it has but i didnt think it would be anywere near that much.

It was a Dynostar, im not sure weather to use it again once the drivetrain is problem free.

[Gareth_R]

would make sense to use it again once the problems are sorted, as only that same one will give an accurate comparison of what difference the improvements have made

[Saxovch22]

ive seen some standard 106 gtis make 140-150 with just a raceland induction
and on the same rollers cammed gtis struggling to make 140

you could just have a healthy engine
fix the bits and then go back and see what the results are like

[Tom5190]

would make sense to use it again once the problems are sorted, as only that same one will give an accurate comparison of what difference the improvements have made

Well it will be at a different RR on the 30th after its got some 708's in it, i wont be able to come back to this dyno with standard cams. I ideally needed a reading thats as low as possible. 100 bhp would of been good haha.

ive seen some standard 106 gtis make 140-150 with just a raceland induction
and on the same rollers cammed gtis struggling to make 140

you could just have a healthy engine
fix the bits and then go back and see what the results are like

Hmmm well i very much doubt its anything over 120, and to be honest its not a healthy engine its abit aged. Will have to just wait and see what it makes with the 708s at RS

[titchster]

It's quite common to see J4s & JP4s make ~140bhp with just breathing mods on rollers. Whether they're actually making that or not, well, that's open to debate.


FWIW, my J4 made 142bhp with a Pugsport and Raceland induction kit. (Oh, and it made 129bhp too, on a different roller :A:)

[Tom5190]

It's quite common to see J4s & JP4s make ~140bhp with just breathing mods on rollers. Whether they're actually making that or not, well, that's open to debate.


FWIW, my J4 made 142bhp with a Pugsport and Raceland induction kit. (Oh, and it made 129bhp too, on a different roller :A:)

Ive never even seen one make around the 130 with them types of mods before, i guess ill just wait and see what the score is at the end of the month:y:

[axsaxoman]

ive seen some standard 106 gtis make 140-150 with just a raceland induction
and on the same rollers cammed gtis struggling to make 140

you could just have a healthy engine
fix the bits and then go back and see what the results are like

140 -150 on std engine --not possible -end of
dyno run should take between 12-17secs to do the run up --if it is alot quicker you will always get incorrect figures

[Ross]

Rolling Road operators want to make customers happy so they come back.

It's not about the power output itself imo, it should be about the consistency of the rolling road from one run to the next so you can track your progress as you improve things. EG:

http://www.tracknroad.com/index-Dateien/image004.gif

If you want a low power figure take it to a heartbreaker dyno - one renown for accuracy rather than bullshit.

Alternatively, put it on an engine dyno - but that's a mission. :)

[Gandi699]

Does anyone have a list of some of the more reliable ones around the country? Wouldnt mind doing my cars

[Barry123]

What was the wheel figure?

Mine made 138 or something like that a 4-2-1 manifold and that's it. Obviously BS though but the wheel figure was around 105 which is much more within the realms of reality.

[Ross]

What was the wheel figure?

Mine made 138 or something like that a 4-2-1 manifold and that's it. Obviously BS though but the wheel figure was around 105 which is much more within the realms of reality.

24% transmission losses. Yeah. Something's not right.

A dyno I went on a few years ago had my low freshly built engine at 112 atw - with low compression pistons, and that was quoting 20% transmission losses giving 135 apparent horses. Totally standard in every way, except low compression pistons - ie, should have been down on the 120bhp figure, not 15 up on it... Go figure.

Another a few years before showed my gti with 147bhp on an air filter and exhaust. Graph to prove it ;)

Not many rolling roads I trust really tbh.

Anyone who knows me knows I swear by Track n Road (http://www.tracknroad.com) - over 10,000 dyno runs now and accurate to 1.5% every time it's compared to manufactures figures. You don't go there for a high reading mind you, you go there for accuracy.

[Tom5190]

NMS is the only place I'd trust to call accurate really but using them isn't an option at the minute

[Jack-CTR]

personaly i wouldnt and dont look at numbers its all just bragging rights,

get it tested some where lets say 121 then do some mods same place get it tested 135 there you go youve gained 14 bhp, doesnt matter what the figure is you just know your running x amount higher than last time, aslong as it runs and pulls well then its just numbers

[blackie_2k5]

Rolling Road operators want to make customers happy so they come back.

It's not about the power output itself imo, it should be about the consistency of the rolling road from one run to the next so you can track your progress as you improve things. EG:


If you want a low power figure take it to a heartbreaker dyno - one renown for accuracy rather than bullshit.

Alternatively, put it on an engine dyno - but that's a mission. :)

this is true with 90%, pretty sure my last session had aims to blow my car up tbf, had around 7 runs back to back ranging from 216-220bhp

an evo tuner who was put back with the runs..

[SnakeVTR]

this is true with 90%, pretty sure my last session had aims to blow my car up tbf, had around 7 runs back to back ranging from 216-220bhp

an evo tuner who was put back with the runs..

Lol your seems to be running around 100bhp more than mine, must be awesome :y: , id love to go boost :fcuk: its just the cost and risk of unreliability in the future