Chip

iTrader: (3)

Ive dont deny his talent, I think a lot of Karl's work. I have driven a few NMS mapped cars, both off the shelf and live mapped, they've ALL been great, but like I said, great mapper or not, he cant get a load of power that simply isnt available, and im sure that SCS in this instance have rung pretty much every BHP out of that setup.

Mike Rainbird

iTrader: (3)

Chip,
You're still not listening (although it may be I'm not explaining it very well ) .

A 0.48 a/r has a physical limit of around 385bhp, BUT it will run safely at this limit for a reasonable length of time due to it's reduced operating rev range and natural rpm shift point.

A 0.63 a/r has a physical limit of around 420bhp, but due to the higher rpm that these run at to produce this power, IF you run a 0.63 a/r at this level, it WILL lunch itself in a relatively short period. It can't live with being pushed this hard due to how the extra engine rpm causes it to over-speed even further than the 0.48 a/r does when this turbo is run at it's max bhp limit (obviously as both turbos are running at this power level with the wastegates fully shut, a turbo running at an engine speed of 7000rpm is going to be spinning faster than a turbo running at an engine speed of 6500rpm). Therefore to make the 0.63 a/r last as long as the 0.48 a/r, you have to pull boost (thus power) out of it so that it isn't overspeeding more than the smaller turbo does. Around 370bhp seems to be where they are TOTALLY reliable at.

So to sum up, all I am saying is that a 0.48 can run at it's limit of achievable power, but a 0.63 can't.

I hope I have explained better this time?

Chip

iTrader: (3)

As before I am listening, you are just talking nonsense about the 370bhp limit, even Jimbo (and hence no doubt Harvey) seems to agree with me on that.


Well the rpm shift point in isolation has relatively little to do with it TBH, its the natural tailing off of boost that causes the turbo to be saved at high rpm, but you can mimic that with the correct mapping on the .63 anyway.


Im sure we all agree on that Mike, no one in this thread is saying a .63 at 420 will be as reliable as a .48 at 385, merely that a .63 at 390-400 will be.

Its not the engine RPM in isolation that is the issue, its the turbo rpm which is key and thats effected by many factors of which engine rpm is only one, you can happily run the engine at high rpm if you limit the boost as the turbo then still doesnt have to spin too fast. Thats just a case of correct mapping.

If you map the boost level appropriately the wasteage on the T34.63 at 7Krpm wont be fully shut though.

Only if you let the boost wander off unchecked, if you set it so that the turbo is only making 390-400bhp, you shouldnt have a problem

Yes, as I have been saying since the start of the discussion you need to pull boost out, however if you pull the boost out inteligently only at the top of the rev range you can peak at 385bhp at the same point you did on the .48 housing and do so with LOWER turbo speeds, so in fact if you wish to expose the turbo to only the same RPM (which is safer anyway due to lower EGTs from less back pressure) you can actually make OVER 385bhp as safely as you can make 385 on the .48

You must be the ONLY person on this forum with any knowledge of engines or turbos that thinks adding a larger better flowing exhaust housing will mean that the turbo now is safe to LESS power




We all know that, but what we are laughing it is you saying that the .63 cant run 420bhp reliably so it needs cutting back not to the 390-400 that would see equivalent load to the 385 on the .48, but that it needs chopping back by 50bhp till its making less power than the .48 can, thats what makes NO sense at all.
There is NO reason at all to run the .63 at LESS power than the .48 while chasing the same reliability.



You are explaining yourself perfectly, we can all understand EXACTLY the incorrect belief that you have.
The problem isnt how you are explaining it, the problem is just that the thing you are trying to explain (why a .63 housing makes a turbo less safe at 385bhp than a .48 housing does) is simply total and utter nonsense.


You have a turbo at 385bhp, doing X turbo rpm and Y engine rpm, you add a larger exhaust housing to allow it to make the same power at the same X/Y values with lower EGTs, and you are now claiming that somehow the turbo that is now spinning slightly slower and experiencing slightly lower EGTs is somehow at more risk than it started

See, I understand 100% what you are saying, but I also understand that what you are saying is completely wrong, maybe if I have also done a good job of explaining you'll now see why

Ima Racing

iTrader: (1)

Mike does seem quite ill informed, is harvey out? As speaking for yourself does not work, unlike the bd10 evidently !

Chip

iTrader: (3)

Flol

J1mbo

iTrader: (1)

Chip, your saying 385 on a .63 will be perfectly safe and acceptable. But you run the .63 so that you can rev the engine and make more power, your not going to limit the boost back to 385bhp are you, other wise your loosing 400rpm of response for no reason other than to lower egt and back pressure (when they're acceptable btw or atleast to 172 mph in 1.7miles on full throttle)


Same with the later part of your post with x/y

Why would you run a larger exhaust housing at the same power just to be loosing throttle response when the smaller housing is acceptable?

Chip

iTrader: (3)

Jimbo, I wouldnt, I would use it for marginally more power than I could get with a .48, that figure was just an example for Mike to show that his 370 figure is clearly too low if he is happy to run a .48 at 385, as if he is happy to run a .48 at 385, then like I have being saying for the whole thread he can run a .63 at MORE than that for the same level of safety.

Do you agree with me on that by the way?
Just cause Mike tends to like listening to people from SCS more than to me, so it might help his understanding if you agree with that

Porkie

iTrader: (1)

Jimbo? really?

I am NOT saying you are lying. I am NOT saying the dyno is wrong... but surely you can understand that SCS would have reason to do it?

Guys paid for a lovely build... and if it makes 330bhp he probably wouldn't be happy!


Nothing but respect for SCS and have and would again use them myself. But that statement is bit naive isnt it?

On another forum I use with engine a guy has just paid a load of money for a 220bhp clubman spec engine. Guess what the engone made on that same firms rolling road?? no... not 223bhp... no not 218bhp... but BANG on 220bhp. Despite the fact that these engines seem to vary massively for same spec elsewhere! I am NOT saying its not gonna be an awesome engine or go well...


People just love big numbers! or at least numbers on the 'right' side of what they are expecting. Engine advantages for example! Remember Spadge going there and making 90000000000000000bhp on 4 greys or something!

NOT slagging SCS at all, or doubting them just to be 1000% clear!

Mike Rainbird

iTrader: (3)

That was a limit I quote where the turbo is TOTALLY safe to run at without reducing it's life in any way, shape or form (as I have always stated).


Re-read my posts, this is what I said .


The ONLY point I was trying to make is that a 0.48 a/r can be run at it's absolute limit and still have a reasonable lifespan. The same cannot be said of the 0.63. I chose a figure of 370, purely as this is within the TOTALLY safe limit and well inside it's compressor map. But the point remains, that the issue is the higher rpm that the 0.63 a/r moves the peak power to and therefore the speed that the turbo spins at, at this figure with the wastegate fully closed.

I said that . However, capping the boost reduces the power.

But power will be reduced (and maybe quite significantly if you slowed it down to the same speed the 0.48 is doing (as that is the only explanation as to why one lasts longer than the other ).

Given that inlet and exhaust cams plus porting work are needed to achieve the higher of the above figures, the 370bhp that I quoted as being safe for a 0.63 is the figure achievable on a completely standard engine (same as on the 0.48 a/r).

SO HAVE I .

But by doing this you have the reduced the spool up by 500rpm and gained nothing in terms of reliability - you have only matched the 0.48 a/r turbo, but lost 500rpm down the bottom - pretty pointless . As you can see, 840°C flat out on the 0.48 a/r map is not excessive.....

You're being a bit silly, as I never said that and you're deliberately picking out specific aspects of my reasoning to poo-poo, rather than trying to understand the big picture (and I know you do) . IF we were comparing like for like rpm ranges, then obviously a bigger turbine is going to give less back pressure than a smaller one. However, we are NOT comparing like for like, as the bigger turbine allows a higher rpm to be used and so although the back pressure at each rpm point is going to be less, that is not the whole picture.

The whole picture would be checking the back-pressure produced at each turbine-housings peak power point and maximum rev limit (they differ from each other by 500rpm). I would surmise that the 0.63 has higher back pressure readings at it's peaks (as that is the only explanation as to why it shits itself, where the 0.48 doesn't).

As clarified, the 370bhp is a standard engine.

More like there is no point in running a 0.63 turbine to the same power as a 0.48, just to achieve the same reliability, when by doing so, you will loose 500rpm of response and by capping the boost at the top end, have no better top end power.....

We will have to agree to disagree on that one. The 0.63 is less reliable, purely because of the extra rpm increase pushes it even further outside it's compessor map, causing more overspeed.

No I am not, I understand that completely, it is you that are missing the differences that each turbine has on the peak power being shifted by 500rpm. Like for like rpm is what you are comparing, where I am not as that is not where the turbos make their peak power figures, one is completely different to the other, and it is this extended rpm of the bigger turbine that is causing the overspeeding in like for like scenarios of closed wastegates. It is the fact that the smaller turbine is making it's peak power so much lower down that is saving it from overspeeding to the same extent that the bigger turbine does. This is all I have maintained from the start, but you seem to be missing / ignoring this point .

Obviously you don't - see above .

polly_x

iTrader: (2)

Its neck and neck in the multi post quote race.............

Lee, you love pub figures too.....I remember when you told everyone that your Westfield had 27 gauages in the dash.

Oh hang on. It did!

J1mbo

iTrader: (1)

Porkie, maybe you and a few others may understand more when I say, we did NOT build this engine, we did NOT spec the engine (we don't use bd10s) all we did way run it in on the dyno and map it.
Hopefully that will clear it up

J1mbo

iTrader: (1)

Yes that's correct chip, I'll be. Honest I've not followed what you and mike have been saying as these multi quotes blow my mind lol I'm not getting involved, I'll stick up for myself and what I beleive in

Mike Rainbird

iTrader: (3)

My 0.48 a/r engine made 385bhp and 403lb ft on four greens (see previous posts). It did 172mph at Bruntingthorpe. I think you can safely say it had the power . Look at the figures "claimed" in the back of PF mag for cars that have done similar speeds .

Mike Rainbird

iTrader: (3)

Dan,
Can you post up your dyno figures - would be interesting to do a comparison with my standard cam engine ?

Chip

iTrader: (3)

Not if the mapper doesnt want the .63 to peak higher it wont as that can be controlled with the boost map, if you want peak power at 6500rpm or even 6000rpm on a T34.63 turbo you can do so just by tailing the boost off after that point!
So if the mapper wants peak power on the .63 to be at the same point it was with on the .48 then it will be as it is capable of making the same peak power at that point anyway, as its well within the .63's boost threshold.
So if you want the same turbo speed you had before, you make 390-400bhp at the point that you made 385bhp before, and then where it really tailed off quickly afterwards on the .48 due to EBP you can tail it off slightly slower on the .63 without needing to increase turbo speed, hence giving you a marginally higher peak power and then a bigger area under the curve at the top of the rev range after that point, all without making the turbo spin any faster than the .48 one did.
Maybe its cause you dont map cars that you dont seem to understand this fundamental point that completely negates everything else you are saying.
If you have an engine with a .48 housing on it making 385bhp and you remove it and fit a .63 housing, then it is now capable of making more power than it did before if mapped correctly. That is the bottom line.

Martin-Hadland

iTrader: (2)

I guess Daniel didn't think he'd get a 5 pager out of his thread

Chip

iTrader: (3)

So only 370 is possible on a t34.63 and also this limit is the same as t34.48, assuming both are with standard head and cams?

Cause I would say the .63 can do more power safely on a standard engine than the .48 can and some people will claim even on the .48 you can make more power than that on stadard head and cams, like this fella 2 pages ago:

Ima Racing

iTrader: (1)

...oh hang on SCS do NOT use BD10's....phew for Rainbird, you can now go back to saying how shit they are

Chip

iTrader: (3)

Why do you think he wants the figures from Daniels car, its so he can point out that at 3500rpm he could have had 4lbft more on the standard cam

Jay,

iTrader: (4)

fuck me you have got me

puppets a d strings chap

lol

were have i said it didnt happen back in the day on real fuel ? read the fucking thread numb nutts

Mike Rainbird

iTrader: (3)

You think I don't know that ? I went from a 385bhp 0.48 a/r to a 420bp 0.63 a/r engine ! The turbo needed replacing every three months on the 419bhp engine, the 385bhp one lasted 2 years and the only reason the 0.48 a/r got replaced was because I "thought" I wanted more power (yet the 0.48 a/r had more area under the graph, despite the extra power of the 0.63 a/r) . Can you still not see the point I am making ? 34bhp extra for a 3 month turbo life isn't acceptable IMO. Neither is capping the boost to achieve same peak power at the expense of a 500rpm loss of spool up.

IMO, the 0.48 a/r engine is the absolute best all round engine you can have, I have said that FOREVER.

Given that the point of the 0.63 a/r is to get more power, what is the point of it if you have to cap the boost at the top to maintain a similar reliability? You loose 500rpm spool up and only gain less back-pressure / lower EGTs IF you match the power-out put of the smaller turbine.

I would only recommend using the 0.63 a/r turbine in the method you mention IF it was for a track car, where the engine was spending a large amount of time at high rpm (so the 500rpm better spool up time of the 0.48 wasn't really necessary), but the reduced back-pressure at high rpm was a benefit to an engine living at high rpm, so needed the reduction in boost for turbo longevity.

JonnyBravo

This is my mates graph of his Scs engine. At the time it was believed to have a ported head and inlet cam, I've since had the engine to bits and it appears to be standard Apart from lower compression, long studs, light blues, T34.48 and a wrc gasket.



Boost is 2.1 bar peak, can't remember what it held to the limiter

Jay,

iTrader: (4)

so who said theres wasa cam and ported head on the engine James

Mike Rainbird

iTrader: (3)

Where did I say that was the only power possible? I said that was all I would want to run a 0.63 a/r at for TOTAL reliability. Anything more is KNOWN to reduce the life span. If you are happy to push the turbo harder (in the knowledge that it won't last as long), that is up to you. The extra rpm operating range is what seems to kill the T34 0.63 a/r turbos.

However, if you have a better explanation as to why they die - then please offer it up .

JonnyBravo

Not Scs Jay. I did speak to them about the history of the engine but they didn't keep records that far back.

I believe it was maybe the original owner that had said about the mods when he sold it on but I don't know that for fact, the car had 400/420 stickers on the wings which was apparently the figures those spec engines made !

Either way it went well

Chip

iTrader: (3)

Mike, it never ceases to amaze me the number of things you seem not to know TBH

And if you had kept it to 385bhp for example by capping the boost at high rpm on the .63 turbo, how long do you think the turbo would have lasted then Mike?


Can you still not see the point that I am making that if you halved those gains and just ran 400bhp or so, it would have lasted ages on that turbo!

Just cause you killed it at 420 doesnt mean it can only do 370 even though the smaller A/R you say is safe at 385


No matter how many times we go round and around we keep getting back to that sill statement from you and no matter how many tangents you go off at or examples of totally different engiens you give, it STILL doesnt make any sense cause it is nonsense!



On that I agree, I like the punchyness of it, hence I still have a .48 on my own T34 YB!


Me too, where it could live quite happily at 385-400bhp (ie not only 370 ) and be long term reliable and you wouldnt care about the slower spool time as you would be always well up into the boost threshold anyway.


The only thing you are saying that I am disagreeing with is that the .63 turbo is only good for 370bhp and the .48 is good for 385 on the same dyno, thats the bit which was nonsense from the start and still is!

Chip

iTrader: (3)

You said .48 is totally reliable at 385
but that .63 is only totally reliable at 370


Thats the thing I initially said was bollocks, and still do.

COCHYN

A bit late to say "come on boys, play nice now"?

Dlatch!

can't beat a bit of passion ford tech banter


ps wtf they on about ?

Chip

iTrader: (3)

To summarise the last couple of pages of multiquote gayness :
Mike says bigger turbos make less power safely than smaller ones, I say that is bullshit, j1mbo agrees with me that its bullshit but found something to agree with uncle mike about too cause he didnt want to hurt his feelings, Ran things its funny that Mike cant grasp such simple concepts and Jay wears a vest and thinks Mike is a cunt but TBH I kind of didnt pay much attention as to why. oh, and of course, phil still likes attension.

COCHYN

I dunno, I think Chip slept with Raybum's dog and Jimbo got jealous or some shit like that

J1mbo

iTrader: (1)

COCHYN

Is that the same as how you couldn't grasp the simple design of an adjustable top mount for 4 pages?

foreigneRS

i presume that the bearings are the same for a .48 and a .63? in which case, for the same shaft speed, you would expect higher bearing loads on the bigger wheeled .63 which may go some way to explaining a difference in reliability (if indeed there is one for the same running conditions)

J1mbo

iTrader: (1)

Yes they are. And the wheel sizes do not differ?

foreigneRS

oh right, i imagined that the bigger housing would have a bigger wheel on either or both ends

so a .63 can just flow more through a lower back pressure through the bigger housing?

J1mbo

iTrader: (1)

That's correct mate

slammed106

farckin wars, it all kicks off on a PF thread.....

opposite lock

iTrader: (3)

Its been an interesting read actually imo aswell as halrious . Reading through it certainly suggests for road cars the .48/34 is a better option in the end.
So engine RPM isn't as said the only factor for turbo speed.Would c/r be a major factor too? We see big variations in engines (not checked mikes 2 engine specs ) compression ratio in YB,s would a .63/34 be more suited to less compression for example. where EGT,s were mentioned made me think compression just a bit of techy to keep things on topic .

Jay,

iTrader: (4)

i bet lol and its the most rainbird posted on here in 6 months to