mythed about bhp

[Mattyfarish]

can anybody explain why my 172 cup made 189bhp on the rolling road yesterday it has got a cat back and the acoustic valve is removed the current millage is 60000.

 

[DanFreemanPhoto]

Dodgy rolling road?

 

[.Kev.]

Most people will point the the rolling road over reading ect, may just be a strong well maintained car. And an over reading dyno.

 

[CuppyDean]

Dodgy rolling road?

Agreed, even freak f4r engines dont produce that much with just a decat

 

[Mattyfarish]

the rolls have just been calibrated or so i have been told but the was stuff there making about its right bhp. i am the second owner on the car and it has a full service history and i have serviced it every six month since i have had the car. it hasnt been decated yet.

 

[CuppyDean]

May have been modified by the previous owner, does it have a raised rev limiter?

 

[imprezaworks]

Oh dear. May have been a bit hasty, or could have the above

 

[Mattyfarish]

there was the cat back on the car when i bought it, the inlet is untouched to the limiter comes in at 6500 7 ish

 

[CuppyDean]

So its not mapped then, must be very friendly rollers for 189bhp

 

[Mattyfarish]

well i am porting the inlet next weekend and the throttlebody and decat it when i have the funds and after that i will find a another rolling road in my area i see what it get on that one i will post a picture of my graph shortly.

 

[Chip-mk1]

Try and find a dyno dynamics, they're still not totally error proof but they are among the more more accurate out there IMHO

 

[CuppyDean]

well i am porting the inlet next weekend and the throttlebody and decat it when i have the funds and after that i will find a another rolling road in my area i see what it get on that one i will post a picture of my graph shortly.

Porting the throttle body? even with correctly ported inlets from a specialist you will only see a few bhp gain, will be interesting to see your RR graph

 

[Mattyfarish]

 

[Chip-mk1]

Thats not from JDM is it? (looks like one of their make believe graphs)
If so those rollers are absolutely renowned for the massive over readings that they give, I know several people who have had figures from them that just wouldnt even vaguely be possible on the engine spec they had and that havent been anywhere near what other rollers said.

 

[Mattyfarish]

the throttleboby is resticting the air flow it is shaped so the air flow is not as good as it should be according to the person i was talking to yesterday and the inlet won't be to hard i will vernier the ports on the head and set about making the inlet manifold the same size but if i go over the size of the ports on the head it will have the same effect of them been to small (loss of power)

 

[Mattyfarish]

yeah it is jdm there was a rolling road day yesterday but they have been calibrated according to a lot of people

 

[CuppyDean]

the throttleboby is resticting the air flow it is shaped so the air flow is not as good as it should be according to the person i was talking to yesterday and the inlet won't be to hard i will vernier the ports on the head and set about making the inlet manifold the same size but if i go over the size of the ports on the head it will have the same effect of them been to small (loss of power)

Hmm never heard of anyone porting out a TB before, i dont see how it can be done to be honest

 

[Mattyfarish]

i am taking it of this week to have a look myself to see what i can do with it because i find it hard to believe myself but i will post pictures and info if i find anything when i strip it.

 

[CuppyDean]

i am taking it of this week to have a look myself to see what i can do with it because i find it hard to believe myself but i will post pictures and info if i find anything when i strip it.

Have a search on here but im sure you wont find anything about porting a TB, theres no way of porting it. If i were you id take your car to another RR and compare results as that graph you have the figures dont add up, 167lbs worth of torque, that is ITB territory

 

[Mattyfarish]

there is someone i know in kendel with one and it was bought brand new last year i will tap him up and see if he has still got it do you know if bike throttle bodies are any good on or are they to small?

 

[CuppyDean]

there is someone i know in kendel with one and it was bought brand new last year i will tap him up and see if he has still got it do you know if bike throttle bodies are any good on or are they to small?

Im not the person to give you advice on ITB theres loads of specialist on here who know alot about them, but i know that bike throttle bodies need extensive machining to make them fit the f4r lump

 

[Will.]

If your car makes over It's stock bhp (ps), everyone on here will say Its over read.

RR are good for seeing power increase in your engine after modifications. So once you have done the modifications you said you're going to do, take it back to the SAME place and see what increase you have made from the modifications.

If you take it to a different place you'll never know what increase you have.

 

[tom172cup]

Somebody on here has bored out the TB and played around with it but I can't remember who it was.

Also what Will... Has said make sense too. Once it's all finished go find a reputable place and put it on
There rollers

 

[Jonff]

Somebody on here has bored out the TB and played around with it but I can't remember who it was.

http://www.cliosport.net/forum/showthread.php?603883-Clio-172-Ph1-Throttle-body-With-%26%23304%3Bncreased-Diameter&highlight=ported+throttle+body

This one?

 

[Mattyfarish]

my brother is a machinist but doesnt have access to a cnc machine but my mate does. i will ask the question on here on what tbs to buy.

 

[tom172cup]

http://www.cliosport.net/forum/showthread.php?603883-Clio-172-Ph1-Throttle-body-With-%26%23304%3Bncreased-Diameter&highlight=ported+throttle+body

This one?

That's the one

 

[Steven103]

EDIT: LOL, scrap all of that. All been covered about except the BS rolling road.

A user can callibrate a RR to say whatever they want it to say. There is one particular company known for ridiculous RR claims that RR'd a member's 172 at 160 BHP (a bit low but we'll see where this goes) standard and then 188 BHP after a remap and backbox. Clearly if a customer has spent £650 odd then they'll want to see good results right, so why not show them good results?

 

[Mattyfarish]

that is what i was wanting to do cut the cost but the if i get itb's i get the mapping to suit

 

[Mattyfarish]

there was a 08 vxr went on and made 278 with a full stainless system on and a 05 standard leon went on and made 222 witch is three bhp down. first run with my clio made 189 then second was 178 the thrid 166 but the speedo sensor is playing up so i need that sort but on the first run it was ok

 

[CuppyDean]

that is what i was wanting to do cut the cost but the if i get itb's i get the mapping to suit

Dont cut cost if your doing ITB's, doing it the right way and properly the first time you wont end up with any problems, take a look at the ITB packages TDF offer, your not gonna go wrong with them

 

[Mattyfarish]

i will i just fancied abit of a challenge that's all i have toyed with putting 225 motor in but i have done engine conversion before and iam bored of them.

 

[Gally]

That's not far off +30bhp over stock. Circa 165bhp.

It's wrong.

 

[Will.]

If your car makes over It's stock bhp (ps), everyone on here will say Its over read.

RR are good for seeing power increase in your engine after modifications. So once you have done the modifications you said you're going to do, take it back to the SAME place and see what increase you have made from the modifications.

If you take it to a different place you'll never know what increase you have.

That's not far off +30bhp over stock. Circa 165bhp.

It's wrong.

See...

 

[Mattyfarish]

but if it is a over read then is not best to get it right then start modifing?

 

[Will.]

You have 2 options.

1: modify then take it back to the same place.

2: take it to somewhere that is "accurate", then modify then take it back to them.

Depends how anal you are about a number that to be honest, will never be exact.

Imo RR are good for finding out the increase in power you make from modifcations and lets face it, with a clio, unless you're sending £££££ on them, you wont see much increase, just better drivability.

 

[theduck]

23bhp difference over 3 runs and you believe them to be even remotely right?

 

[Mattyfarish]

well i am hoping to spend alot this year but is 250 a realist figure or is that just fantasy?

 

[Mattyfarish]

there was three different reading due to the fact the speedo sensor was playing up.

 

[Will.]

250 from n/a is optimistic. Prove us wrong though

 

[Mattyfarish]

well interal work will have to be done restoked crank maybe the answer.