Boost differences

[SP33DY]

First post!

Right everyone I'm new to the site and this is my first post so hope you don't mind this techie question.

I recently had my car (clio 182) fitted with the Ktec low pressure turbo conversion.

When the fitting etc.. was being carried out I was told it would be running approx 220bhp at 7 psi (0.5bar) boost.

After the fitting I took the car to RStuning for some tweaking of the original map, as it was originally done on Seans 172 clio. On Pauls rollers the best he could get was 205.9 bhp (the print off confirmed 0.5bar of boost)

Moving on, there are a couple of supercharger kits being developed for clio's in both high and low boost formats. Both the low boost conversions are claimed to be running at 0.5 bar yet putting out 250+bhp.

So the question is what is the difference between turbo boost and supercharger boost at 0.5 bar that should yield such significant power differences? Considering both conversions use standard internals, CR's etc..

Surely boost is boost?

From all the research I've done, a turbo should have the highest gains due to the fact that it runs from exhaust gasses.
Where as a supercharger has to sacrifice some of the bhp gained, due to the extra drag placed on the crankshaft to turn it.

I did a search on google about this and all I could find was various groups argueing which was best.

Hopefully some of the experts can break it down into simple terms for me.

Cheers

SP33DY

[Os8472]

Damn the first time I get to be first posting about a can of worms topic and the smiliey has gone oh well

You've pretty much hit the nail on the head, a turbo in theroy will give you more power but you'll have lag where as a super charger will have no lag but will take some engine power to make it turn.

Did K-tec give a dyno print out when they fitted the conversion or did you do it yourself?

[car.crash]

i would be very wary of tuners claimed bhp output. they love to exadgerate.

[BriC]

Whilst we wait for Scoff, Andy, etc to reply, have you got any pics of your clio?

[Os8472]

i would be very wary of tuners claimed bhp output. they love to exadgerate.

That was gunna be what I said next

[SP33DY]

New poster! (less than 10 posts)

Nope being the lazy person that I am and the fantastic fitted price they gave me (as it was the first 182 clio) I let them carry it out.

They put a safe map on the car and the intention was to go to RStuning who would create a generic map to be sold with the kits (as they are DIY kits) before carrying out a custom map.

As it stands the car has Janspeed exhaust, decat, open induction kit., GT28 ball bearing turbo, FMIC and a custom map.

[SP33DY]

New poster! (less than 10 posts)

Bloody hell some quick replies there!!

No pics yet but should have some after the weekend and I'll post them up.

[youngscottie]

sounds like alot of work for not much gain
your spec list is just crying out for a corrected cr and lots more boost
how would the na cams affect the turbo setup???

remember tuners dont make ££ by giving real world bhp figures

that said sounds like a great car (turboed 182)

[SP33DY]

New poster! (less than 10 posts)

sounds like alot of work for not much gain
your spec list is just crying out for a corrected cr and lots more boost
how would the na cams affect the turbo setup???

remember tuners dont make ££ by giving real world bhp figures

that said sounds like a great car (turboed 182)

Thats what I thought about the gains, but Paul at RStuning said most 182/172 clios are only putting out between 160-165 real bhp so that cheered me up a little.

I'm also already on the case for further upgrades (turbos are to addictive) and have a set of uprated rods just deciding what pistons to get? wossner or JE custom?

As for the cams mate not sure how they effect things?

[Ashy]

as per my post on cliosport

If you were told that at 7psi your conversion would make approx 220hp, and at 5psi you are making 205h then I don't understand the issue?

Why not just increase the boost to 7 psi? I guess on the low pressure conversion you haven't lowered your compression? so at 0psi you would be making 170hp and at 5psi you are making 205hp, so thats approx 7hp per psi. so if you increase the boost to 7psi you should "in theory" make 219hp... So thats not too far away?

Putting your car on the rollers is never an exact science, there are so many variables that need to be entered, differences between rolling roads and calculations made to give you a flywheel figure that your result is only ever an indication.

If the car runs well with the conversion, feels fast on the road then thats all that matters, isn't it?

If people are claiming 250hp with a charger thats fine but you can manage 250hp from your setup aswell.

Interestingly I've lowered my CR to approx 9:1 and I still manage to make 238bhp and 230lb/ft at 7psi.

[Ashy]

also, its better to ask questions about "what to do if your girlfried dumps you?" or "who's got the best @rse Britney or Christina?" on Cliosport... If you ask a technical question they just start spouting sh!te.

[Ashy]

and another thing, I see you're in Sunderland, be good to see you at a local meet soon? would like to have a look over your car!

[SP33DY]

New poster! (less than 10 posts)

also, its better to ask questions about "what to do if your girlfried dumps you?" or "who's got the best @rse Britney or Christina?" on Cliosport... If you ask a technical question they just start spouting sh!te.

Love it.

Your right there mate there is a load of pillocks over there but there is also a few really knowledgable guys. I's just a shame there's so much **** to sift through to find it.

Anyway back on topic it's currently running 7 psi/ 0.5 bar

[J8TRO]

are the figures being quoted and given to you based on the fly wheel or at the wheels? these figures can vary quite a bit.

I second the comment about tuners and claimed BHP but i'm stumped about the turbo/charger same boost different out puts?

It would be interesting to see how many 172's are 172, 182's are 182 and even 197's are providing there badges claims.

[SP33DY]

New poster! (less than 10 posts)

and another thing, I see you're in Sunderland, be good to see you at a local meet soon? would like to have a look over your car!

Depends if I'm going to get a lecture off you about all the bellends on cs? LOL

[SP33DY]

New poster! (less than 10 posts)

are the figures being quoted and given to you based on the fly wheel or at the wheels? these figures can vary quite a bit.

I second the comment about tuners and claimed BHP but i'm stumped about the turbo/charger same boost different out puts?

It would be interesting to see how many 172's are 172, 182's are 182 and even 197's are providing there badges claims.

Mate I have 3 read out graphs

whp and manifold pressur
fhp and torque
whp and A/F

Will have to get hold of a scanner and post them up.

[Scoff]

Where did 5psi come from ? Was that something from Cliosport ?

You can simplify expected power a little by using this rule of thumb:

1) We'll assume that your lower c/r 2l f4r now makes a genuine 150hp with no boost.

2) At no boost you have 1bar of atmosphere to charge the engine. Therefore at 1 bar of boost you have 2 bar's worth of pressure to charge the engine, and keeping things really simple here you can assume that you will get roughly twice the air flow too, and since air flow is power you will get twice the power.

3) So you've got 150hp with no boost, at 0.5bar gauge (1.5bar absolute) you could expect:
150hp x 1.5bar = 225hp.
At 1 bar with the right turbo you could expect:
150hp x 2.0bar = 300hp.
and at only 5psi you could expect:
150hp x 1.35bar = 201hp.

You get the idea

A small amount of boost on that engine will make a big difference. A couple of psi goes a long way

[Ashy]

New poster! (less than 10 posts)




Depends if I'm going to get a lecture off you about all the bellends on cs? LOL

Nah mate, LOL, just a bit Reno Turbo crack

I see I miss-read your post, thought you said it was only running 5psi. 205bhp does seem a little low at 7psi, whats the exact spec of your conversion, which ECU are you using?

[Ashy]

Where did 5psi come from ? Was that something from Cliosport ?

You can simplify expected power a little by using this rule of thumb:

1) We'll assume that your lower c/r 2l f4r now makes a genuine 150hp with no boost.

Like I said, its late and I must of miss-read the 5psi carry on... I don't think the low pressure conversions do lower the CR? Could be wrong though.

[SP33DY]

New poster! (less than 10 posts)

Forgot to add in the opening post that it's running on stock internals at standard CR which I believe is about 11:1?

So as it stands the facts are

CR 11:1
Boost 7 psi/0.5 bar
Power 205.9 bhp and 182lb/ft

[SP33DY]

New poster! (less than 10 posts)

Nah mate, LOL, just a bit Reno Turbo crack

I see I miss-read your post, thought you said it was only running 5psi. 205bhp does seem a little low at 7psi, whats the exact spec of your conversion, which ECU are you using?

It's on the standard ecu unlocked by RStuning the car has Janspeed exhaust, decat, open induction kit., GT28 ball bearing turbo, FMIC and a custom map.

As for the meets, is there many up our way?

[Scoff]

Like I said, its late and I must of miss-read the 5psi carry on... I don't think the low pressure conversions do lower the CR? Could be wrong though.

In that case it does sound low then doesn't it. It might be worth making sure there is definately 7psi there. Its also worth checking for boost leaks - plenty of things to leak boost on a standard 172 manifold, I had to weld all kinds up on mine to seal it up.

[SP33DY]

New poster! (less than 10 posts)

In that case it does sound low then doesn't it. It might be worth making sure there is definately 7psi there. Its also worth checking for boost leaks - plenty of things to leak boost on a standard 172 manifold, I had to weld all kinds up on mine to seal it up.

On the RR graph it shows a peak of 0.55bar (manifold pressure) at 3500rpm trailing off to 0.4 bar at 6500rpm but no spikes or fluctuations.

[Scoff]

Oh ok, but since peak power is measured at 6500rpm or more then you will have only had 5.5psi or so at that point. That's enough to throw away 15hp, see my "rule of thumb"

How is the boost control done ? Is it manual ? You might need to work on removing that boost spike and making it hold 7psi up until the redline.

[Ashy]

New poster! (less than 10 posts)




On the RR graph it shows a peak of 0.55bar (manifold pressure) at 3500rpm trailing off to 0.4 bar at 6500rpm but no spikes or fluctuations.

Can you scan and upload the graph?

Also any pics of the conversion?

[SP33DY]

Oh ok, but since peak power is measured at 6500rpm or more then you will have only had 5.5psi or so at that point. That's enough to throw away 15hp, see my "rule of thumb"

How is the boost control done ? Is it manual ? You might need to work on removing that boost spike and making it hold 7psi up until the redline.

Not sure about the boost control, give me a chance to poke around the site and get up to speed on whats what. But I don't think they fittted an eloctronic solenoid so am I right in guessing that the waste gate is manually set for boost limit?

Also been trying to get the specs of everything out of Ktec but there being well cagey. One told me it was a GT28 (which it is) another it's a custom BB turbo to there spec and that it's good for 320 bhp. Looking at all the data I've managed to source I'm 95% sure its the GT2860r.

Will post up more info as I find it out

[SP33DY]

Can you scan and upload the graph?

Also any pics of the conversion?

Will try and sort a scanner out to upload the graphs

Sort off, they used my car to create the installation instructions for the DIY manual and I've got a CD with all the photos on but to be honest theres nothing that interesting on there as it's all alot of close up camera work.

[Ashy]

Also been trying to get the specs of everything out of Ktec but there being well cagey.

So you paid them to work on your car and they wont tell you what they used?

Fecking tuners!

[Scoff]

Yes, boost could just be manually set. follow the pipe from the actuator to see where it goes

[Adey aka Ewok]

one major difference, is the turbo conversion runs an unlocked stock ecu, there are still concerns as to how well it can be mapped, would be intresting to see your dyno graph cus every one ive seen has been relying on the knock sensor to control everything, note very eratic spiking on the dyno plot. the supercharger conversion that is about to go on sale runs with a fully mappable standalone ecu that seems to give you alot more control over whats happening. the supercharger increases boost all the way through the rev range so im not sure if helps with the top end power. also, i have been out in the sc clio and **** me it is quick, almost like an m3 engine in the clio rather than a boosted unit

[SP33DY]

one major difference, is the turbo conversion runs an unlocked stock ecu, there are still concerns as to how well it can be mapped, would be intresting to see your dyno graph cus every one ive seen has been relying on the knock sensor to control everything, note very eratic spiking on the dyno plot. the supercharger conversion that is about to go on sale runs with a fully mappable standalone ecu that seems to give you alot more control over whats happening. the supercharger increases boost all the way through the rev range so im not sure if helps with the top end power. also, i have been out in the sc clio and **** me it is quick, almost like an m3 engine in the clio rather than a boosted unit

Scoff I'll have a look next time I get the car out and see where the pipe goes.

Adey RStuning's SC conversion runs on an unlocked ecu. Now the power graph is pretty smooth to be honest and Paul even admitted that if I was to go for a stand alone he would only be able to replicate similar results and probably not improve it.

[Adey aka Ewok]

yeah i know whos mapped it and i dnt wana name names but personaly i feel i know a bit more than average jo when looking at a dyno plot, and when i say i can blatently see the spiking on a plot i know full well the ecu is going nuts of the det sensor, so its either faulty or needs proper mapping. Plus the rs tuning car is running more than .5bar if ure using that as a power ref

[Mart]

cus every one ive seen has been relying on the knock sensor to control everything, note very eratic spiking on the dyno plot

lol, nothing's progressed from the c1j/209 aei then

[SP33DY]

Looking at the RStuning and GDI conversion as comparisons. Pauls in the early stages of its conversion (as I know its running more now) and Andy's how he's about to sell it now.

I have heard that alot of the gains are down to the omex stand alone.

[Andrew Cooke]

I'll think a bit more later, but 2 things jump to mind, first, you've lost the fancy exhaust manifold, and that will cost you power, given the alleged difference between the 182 and 172, it may be as much as 20 hp.

Which T28 did they fit? I wouldn't fit anything smaller than the GT28RS with a .86 back end, anything less is likely to be restrictive with the relatively hot standard NA cams.

Get your plots up, is it still making 0.5bar at peak power rpm?

anyway, I need to eat

[Mart]

Just out of curio', which software does this RS Tuning company use to upload maps to the Megane/225 ecus? Is it based on the FastChip setup per chance?

[SP33DY]

I'll think a bit more later, but 2 things jump to mind, first, you've lost the fancy exhaust manifold, and that will cost you power, given the alleged difference between the 182 and 172, it may be as much as 20 hp.

Which T28 did they fit? I wouldn't fit anything smaller than the GT28RS with a .86 back end, anything less is likely to be restrictive with the relatively hot standard NA cams.

Get your plots up, is it still making 0.5bar at peak power rpm?

anyway, I need to eat

Both the supercharger conversions are fitted to 172's, which AFAIK haven't had 182 manifolds retro fitted.

This is the turbo supplied and fitted by Ktec

http://www.k-tecracing.com/show_product.asp?id=2132

Any turbo spotters able to identify it for me?

There was a receipt for the turbo left in the car but it just said GT28 BB which would equate GT28R now looking at the power capabilities of each GT28 turbo and the one which seems most fitting for the application is the GT2860R? Also it has .42 AR on it

[Mart]

The GT25r and 28r both have either bolt-on turbo inlets or outlets, unlike the one pictured on K-tec's site. It's not the GT28rs either as that has .6 a/r compressor housing.

If I were a betting man, and I'm sure Adam L will correct me, but that 'M24' .42 a/r housing looks v familiar to the everyday 'T28' 360deg' bearing esque blowers that the gtt tuners used to knock out back in the day. I think the compressor housing origins are from ye olde T3 60trim turbo.

[SP33DY]

Spoke to Ktec earlier.

It is a mechanical manual set boost.

They did say that it was a gt28 which was modified due to clearance issues with the clearance for the wastegate.

I'm bringing the car into work tomorrow so will stick my head down the back of the engine and see what info I can see.

[Mart]

Hi, I'm Mart, and my posts are invisible...

I'm struggling to find any current GT28 series blower that runs a .42 compressor housing that doesn't have bolt-on inlets/outlets...

[Andrew Cooke]

Hi, I'm Mart, and my posts are invisible...

I'm struggling to find any current GT28 series blower that runs a .42 compressor housing that doesn't have bolt-on inlets/outlets...

that'll be an escort cover, 'looks' like a 60 trim on the inside, but it's the exhaust housing that's interesting. Have they stuck a .49 on it, or kept the original .64? Either way, it's a small turbo.

See if you can get a picture down the back of the engine showing the exhaust housing / wastegate / actuator area.

[Mart]

Yep, T series though, not GT, so not sure what shady info K-tec is giving out...

[Mart]

I'd also question the 350hp claims in that advert too.

[Adam L]

That turbo won't flow the 320hp that's been mentioned. That potential power will only happen with the .64 exhaust and .60 a/r housings supplied by Garrett.

I just read the K-tec advert, it won't flow the 350bhp they claim if Garrett don't even rate it past 330hp.


http://www.turbobygarrett.com/turbob...R_466541_1.htm

[Mart]

It's not a 2560r though...

The GT25r and 28r both have either bolt-on turbo inlets or outlets, unlike the one pictured on K-tec's site. It's not the GT28rs either as that has .6 a/r compressor housing.

If I were a betting man, and I'm sure Adam L will correct me, but that 'M24' .42 a/r housing looks v familiar to the everyday 'T28' 360deg' bearing esque blowers that the gtt tuners used to knock out back in the day. I think the compressor housing origins are from ye olde T3 60trim turbo.

By 'inlets' and 'outlets' I'm referring to where (and how) the intake/air-filter pipe attaches, and likewise for the boost hose.

[Rob@Backyardracing]

How much is that blower ... How come no one goes T04e style route ?

[SP33DY]

Just pulled the car out of the garage and stuck my head under the bonnet.

From what I can see (limited admittedly) it's the same turbo as on the ktec link, I can see the AR.42 on the intake side. Cant see anything on the exhaust side except 866 MX which is cast into the top of the exhaust side.

Also I found this on garrett's web site and it's this that led me to believe it was the GT2860R with a optional intake

http://www.turbobygarrett.com/turbob...R_707160_7.htm

[Andrew Cooke]

How much is that blower ... How come no one goes T04e style route ?

not sure how much space there is down the back, and the available manifold has a T2 flange

[Andrew Cooke]

you won't see anything on the turbine, the size is on the inside. A pic may help as there are some good eyes out there

[Adam L]

It's not a 2560r though...

I'd imagine the core would be though, especially if it's using the 60 trim wheel. K-tec haven't exactly branched out much with development, so I bet they still use the same core they used on the 5's.