Mr Leigh

I plan to fit a scorpian exhaust, this has a 3' through bore leading to a 4' tail pipe and also replaces the cat. Is a 3' system likely to rob me of torque? It will be fitted to a UK MY99. any help on this would be great.

Jonathan

We did do a comparison on my old STI V between a Blitz Backbox and a 3" full Blitz system.

Yes we did lose low end torque. About 10bhp but gained it above 6000. I would stick with a backbox only IMHO

Jonathan

Speak to Power Engineering. They done loads of tests now.

Mr Leigh

Thanks for the help guys, I would really like the extra vocals of removing the cat.Met a guy with an STi 4 at a local garage with the scorpian 3' fitted, it sounded like a Harley Davidson, but he had had it fitted from new ( Like I shall be ) and so did not know the differance. Will the drop in torque be noticeable? Johnathan, did you mean I will also get a drop in BHP in the mid range. what extra BHP am I likely to see at the top end? Thanks for the advice I will also ring PE this week. I think this BBS service is great when its working.

Jonathan

The loss in the low to low mid range was bhp as well as torque.

It might be different for a Scorpion system, GGR etc. Maybe at the next Rolling Road shootout we can address that one or earlier when PE get there full system, we can get some comparisons carried out.

The full Blitz system felt quicker, but that was because it was louder. The Rollers showed us otherwise.

Jonathan

Pete Croney

If the exhaust gas speed is allowed to fall too low, you will lose exhaust port scavenging. This is where the momentum of the exhaust gas helps syphon gas out of the cylinder of the newly opening exhaust port. It's effect is less important on turbo charged competition cars, but still important all the same. Its effect is most important off boost, when the gas velocity is already low. Any drop in scavenging ability will raise the point at which the engine is running efficiently enough to produce sufficient gass to spin the turbo.

On WRC cars, the works teams fit different exhaust sizes for different events. Gravel events require massive power, to maintain speed over surfaces which offer a high rolling resistance. These cars will use 3" or 3.25" exhausts. On tarmac events, acceleration out of corners (torque) is more important and WRC cars use 2.5" or 2.75" exhausts.

Nick

>David Power
Does this mean that your new downpipe will only be suitable for use with a full Power Eng exhaust system?

BPM

In regards to exhausts, I feel strongly in this case since we BPM have had the opportunity to work with the WRX since 1994 since there are no restictions on the import of this vehicle. Every model is different despite what others might say. Our 3" twin dump system with High flow cat and muffler , full stainless steel has been dyno proven to 40-51HP alone! We have patented the system and we can quite emphatically state without fear that it will take a minimum of 5/10 to 8/10 off your quater mile. HPC coating will then aid in keeping temp low. We have found and testing with Possum Bourne that the 3" is the best solution, the results you will get from this system are unparalled and the DYNO shoot outs will prove this.
If anyone would like pics of the unit and the dealers handling BPM product please email me, our official launch is not until Ausgust in EVO but you can't hold back people who want the a better solution.

Greg
Booost Performance Motorsport
"The ruthless pursuit of speed"

DYNT

High torque pipe size 2.75" and HP 3". Try and find a good front pipe for the car. I used 3" all the way .... with box of course.

Fujitsubo make good exhaust system. If you have lots of time ... buy Exhaust Wrap and start wrapping the exhaust manifold and front pipe. Might be able to get 5hp by doing this.

40-50bhp exhaust system???? .... hmmmmmmm..no way. Well do dyno it. Would be very interesting to read the dyno chart.

BPM

We will guarantee 40HP and add to this if we get beaten by another system company we will give away and full exhaust system on the day to the spectators + an anti lift Kit.

Greg Nikolettos
Boost Performance Motoring
UK Marketing Manager

Ian Cook

What effect does the exhaust have on the torque figures for the car? Its no good having massive HP figures if the torque drops.

BPM

We will guarantee 40HP and add to this if we get beaten by another system company we will give away and full exhaust system on the day to the spectators + an anti lift Kit.

Greg Nikolettos
Boost Performance Motoring
UK Marketing Manager

BPM

Torque increases due to the twin dump system

Ian Cook

BPM,

Excuse my ignorance, but could you explain what Twin Dump means, as its not terminology i have heard before, unless it relates to the dump valve on the turbo????

JohnS

iTrader: (1)

BMP,

further to Ian's comment, can you explain what all your exhaust system comprises.

Is it a full system including the exhaust manifolds, or just a Cat back system (but replacing the Cat it seems).

Mike Tuckwood

It is a poor show when somebody who claims extensively that they are involved in supplying specialist products as this, do not explain themselves fully.


It is my guess that Greg is possibly talking about the exhaust system which blows off excess pressure released by the dump valve via a seperate butterfly in the joint between the turbo housing and the exhaust?


This allows vented gas to blow straight into the exhaust bypassing the cat and allowing the turbine impellors to retain momentum, hence reducing lag.

If I have got this **** about face. (quite likely) I think it was on the MRT (surprise surprise) site that I saw it.

Come on Greg, if you want us all to know how good your kit is get your website up with some good pictures, accurate technical explanations, performance gains and costs.


I have E mailed Greg (BPM) about his exhaust claims with my cat removal pending at the end of this month but still not had any specific details back, he did tell me that all of the work will be carried out by Autosportif.

Why does that name ring a bell?


Mike.

Mr Leigh

I have decided to fit the scorpian system complete. In the name of noise and to see how it compares to others on the rollers, I read the report on the catalunya rally, I so cant wait to go! I look forward to receiving that free exhaust BPM even if it's not the scorpian system that makes more power.
God I am so excited, its like Christmas, not long now, the car that is

BPM

I have emailed pictures to those who have requested and I am limited to the amount of "advertising I can do on this site. The twin dump refers to the system utilising two ports one for the wastegate and one for the turbo.
It is a full 3" Stainless Steel Mandrel Bend system with high flow cat and muffler.
We are working with Autosportif for the engine rebuilds so you will see how serious we really are.

Greg

BPM

In regards to Mike statement Autosportif will ONLY be doing the engine work ie conrods , pistons etc all the other product is ours.

Ian Cook

Thanks Greg, that cleared that up.

Dont feel we are picking on you specifically, noone advertises on the site, any posts about companies and products come from recomendations, and word of mouth. As you will probably learn once you are up and running.

JAMES.M.

HI THERE.
I AM JUST WONDERING WHAT DAVID AT P.E. AND PETE AT S.SPORT HAVE TO SAY IN REPLAY TO BPM's EXHAUST "CLAIMS"?

Ian Cook

You will probably find they will say very little, as they would probably not liek to get drawn into such arguments. Their customers seem to be saying it all for them at the moment

Mr Leigh

Dyno test all the systems on the same car on the same day. This would make a great article for true grip. I will have my baby fitted soon, I'll let you know.

EVOBOY

AS I'M FROM AUSTRALIA WE DON'T GET THE SCOOBYSPORT EXHAUST SYSTEM.THE MAIN ONE AROUND IS THE MRT 3INCH EXHAUST SYSTEM.IWOULD
LIKE TO KNOW IF ANY ONE HAS GOT ONE OF MRT'S
SYSTEMS AND HOW DOES IT RATE TO YOUR SYSTEMS
HELP PLEASE!

BPM

MRT being a good company , that has done well in the marketplace has some good product.
Now there are so many options here in Australia, like APex, Greddy, Trust, Blitz MRT, AVO,Croydon, and BPM's.

We would like to prove that, yes you can extract 45hp and increase torque on some WRX models and the reason why the MY99 does not do as well.
We launch July 7 in EVO, the exhaust picture can be emailed to you if requested, it has been patented to protect our R & D.
This is only the first step step how about an engine dyno shootout arranged with our 320HP and 400HP bolt on kits against anyone eles in the world. We came back from japan and we have some fantastic figures.

Regards


Greg Nikolettos
BPM/AVO
UK/USA Marketing Manager

Pete Croney

James

Both David P and I are more concerned with torque and driveability. WRC cars have massive exhausts fitted for gravel events, where there is a high rolling resistance. For tarmac, most WRC cars use 2.5" or 2.75" systems, as these give the strongest torque curves.

"Horse power sells cars (and exhausts ;-) ), torque wins races".

BPM

To answer the question I am sure you know know Possum Bourne who has won the last South Asia Pacific WRC Rally. Well he utilises the LINK System and torque is where we go , if you want HP and torque that is achievable at the same time and yes our 400HP turbos do have good drive ability even for your roads.
if you would like me to quote torque figures only I will do so so you can see what we have acheived working on the Imprezza since 93.

BPM/AVO

Mr Leigh

It went on easily and sounds fantastic. Wonderful. Next up a GGoode induction kit.

Bob Rawle

Was at PE on Friday 16th for a phase one "adjust" (Phase 1.1 now!!) and saw delivered a prototype exhaust system. It was fabricated but the quality was superb. Listening in to the conversations I gathered that this was the prototype for the PE 3 inch downpipe, mid box and back box system. It had a separate pipe for the wastegate gases (as it should) and the downpipe contained a hi-flow cat to keep things legal. The cat only increased the downpipe diameter by about 25mm. I was there for about 4 hours while David re-mapped my car again and I was able to get a good look at it. Twin tail pipes were fitted to the prototype but I overheard a conversation that indicated that a oval version of the back box would also be available. The back box is "stuffed" with stainless steel wire not fibre so should last for ever. IMHO it was one of the best systems that I have seen, even though it was a prototype. Tried to find out obout prices etc but too early for that. The prototype is to be used to evaluate ease of fit, adjustment on car, and of course performance. Once they are happy with it the master jig will be produced using this as the template. I believe that the system will fit any Impreza regardless of model year or colour (grey or otherwise!!)


Lets hope that David has something to show us on the 14th.

Bob Rawle


[This message has been edited by Bob Rawle (edited 18-07-99).]

[This message has been edited by Bob Rawle (edited 18-07-99).]