Fitted the .48/60 T3... Interesting results! LEAKS FOUND!
29-06-2011, 09:26 PM
#1
Fitted the .48/60 T3... Interesting results! LEAKS FOUND!
Fitted it this afternoon, went out for an hour or so to get it mapped safe for driving and the results are interesting...
At 16psi the car now needs the same amount of fuel as my previous .36/50 did at 26psi so the VE of the engine has increased massively!
But.. It wont hold more than about 16-18psi!! My AVC-R is at around 70% duty to hold that and if I try for anything more like 21psi then I get terrible surge going from 21psi down to 16psi then back up again... What could my restriction be?
I'm on a stock exhaust manifold so should have no problem getting rid of the gasses as they flow for 350bhp+, my head is a NMS head with the Newman off the shelf RST cam and lifters so shouldnt be them either?!
The engine breathes fine right to the limiter of 6600rpm still needing plenty of fuel (VE doesnt drop off like it did on the .36/50) so I dont see a problem getting air into the engine, it looks like typical turbo surge with exhaust gasses struggling to get out.
Thoughts and opinions welcome as always....
At 16psi the car now needs the same amount of fuel as my previous .36/50 did at 26psi so the VE of the engine has increased massively!
But.. It wont hold more than about 16-18psi!! My AVC-R is at around 70% duty to hold that and if I try for anything more like 21psi then I get terrible surge going from 21psi down to 16psi then back up again... What could my restriction be?
I'm on a stock exhaust manifold so should have no problem getting rid of the gasses as they flow for 350bhp+, my head is a NMS head with the Newman off the shelf RST cam and lifters so shouldnt be them either?!
The engine breathes fine right to the limiter of 6600rpm still needing plenty of fuel (VE doesnt drop off like it did on the .36/50) so I dont see a problem getting air into the engine, it looks like typical turbo surge with exhaust gasses struggling to get out.
Thoughts and opinions welcome as always....
Last edited by Karlos G; 20-07-2011 at 07:09 PM.
29-06-2011, 10:12 PM
#2
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It's quite odd that you've got surge on a CVH to be honest. I've only ever seen surge on a CVH when some idiot machined out the compressor housing and fitted a T4 compressor wheel inside of a .42 housing!
My car only surges once it gets up to about 1.85 bar on a GT28 but it's quite a big turbine housing without the RST elbow and a big compressor wheel, standard exhaust manifold, ported inlet, NMS head, 3" exhaust, GRS intercooler.
The only way you'll know for sure where the restriction is, is to monitor pressures around the engine. Try either side of the intercooler first.
It may be that your compressor wheel is now too big. A 2wd Cossie compressor wheel is a 57 trim opposed to the 4x wheel being a 60. Might be worth you trying that.
My car only surges once it gets up to about 1.85 bar on a GT28 but it's quite a big turbine housing without the RST elbow and a big compressor wheel, standard exhaust manifold, ported inlet, NMS head, 3" exhaust, GRS intercooler.
The only way you'll know for sure where the restriction is, is to monitor pressures around the engine. Try either side of the intercooler first.
It may be that your compressor wheel is now too big. A 2wd Cossie compressor wheel is a 57 trim opposed to the 4x wheel being a 60. Might be worth you trying that.
no surge what so ever here!
29-06-2011, 10:41 PM
#4
I cant see it being the comp side, surge is generally caused by exhaust gasses not being able to get out fast enough.. At least thats my understanding 
Cam timing is stock Jimbo, I dont have a vernier fitted.
Cam timing is stock Jimbo, I dont have a vernier fitted.
Last edited by Karlos G; 29-06-2011 at 10:48 PM.
30-06-2011, 07:28 AM
#7
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At what RPM do you have the surge? Probably low down as that is where surge usually taken place. Can't you just lower the boost at that RPM band? I know this is more like removing the symptoms than removing the actual problem, but could still be worth while doing.
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30-06-2011, 07:33 AM
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The restriction can be anywhere from the compressor housing all the way to the tip of the exhaust. The compressor wheel is producing air that has no where to go!
30-06-2011, 09:13 AM
#11
-31 Garrett 3/4 of a hole preload mate.
Yeah I see what your saying Dazc
30-06-2011, 09:42 AM
#12
The only time I saw this was when i got my cam timing wrong, and it surged at 4k put the cam timing back and it was as good as normal
I think your cam could possibly be restricting it. This is the beauty of a dyno. You can record all data at each degree of cam timing moved to optimise the engine where you will just be guessing on the road
I think your cam could possibly be restricting it. This is the beauty of a dyno. You can record all data at each degree of cam timing moved to optimise the engine where you will just be guessing on the road
30-06-2011, 10:25 AM
#13
See I was thinking maybe my cam... It's strange that it seems to have hit a wall in exactly the same place as my previous turbo (fuelling requirements are identical albeit at a lower boost pressure) and wont flow any more.
Perhaps I'll get a vernier and have a play, a dyno would be very useful yes!
lol
But I will be able to tell by how the VE changes and also if it has an effect on the surgeof course, I also think I'd better get a new inlet manifold sharpish too as we know they are restrictive.
Perhaps I'll get a vernier and have a play, a dyno would be very useful yes!
lolBut I will be able to tell by how the VE changes and also if it has an effect on the surgeof course, I also think I'd better get a new inlet manifold sharpish too as we know they are restrictive.
30-06-2011, 01:22 PM
#16
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Try advancing the cam timing a little if you suspect that as the problem Karlos.
I was looking into building a dyno as apparently, to brake the engine via eddy current is quite easy. To keep the motor that you use to brake the engine cool is another matter! That would be ok for loading engines up and down for mapping purposes but wouldn't give any power figures.
I was looking into building a dyno as apparently, to brake the engine via eddy current is quite easy. To keep the motor that you use to brake the engine cool is another matter! That would be ok for loading engines up and down for mapping purposes but wouldn't give any power figures.
30-06-2011, 03:43 PM
#18
Too many posts.. I need a life!!
Hello karlos,
At what rpm was the boost surging?
With the electronic boost controller you should be able to tailor the boost curve
vs. RPM.
You should be able to plot your engine airflow demand on the 60 trim compressor map you posted.
Also take a look at this turbo calculator: http://www.squirrelpf.com/turbocalc/index.php
It is quite good.
I input a 1.6 engine, and 250 hp, and .55 bsfc, and 1 psi intercooler boost loss.
I also mapped the 60 trim T3 with these parameters.
It looks like 4000 rpm before you can be at full boost (over 18 psi)
Cheers
At what rpm was the boost surging?
With the electronic boost controller you should be able to tailor the boost curve
vs. RPM.
You should be able to plot your engine airflow demand on the 60 trim compressor map you posted.
Also take a look at this turbo calculator: http://www.squirrelpf.com/turbocalc/index.php
It is quite good.
I input a 1.6 engine, and 250 hp, and .55 bsfc, and 1 psi intercooler boost loss.
I also mapped the 60 trim T3 with these parameters.
It looks like 4000 rpm before you can be at full boost (over 18 psi)
Cheers
30-06-2011, 04:45 PM
#21
PassionFord Post Whore!!
30-06-2011, 06:38 PM
#23
PassionFord Post Whore!!
30-06-2011, 07:59 PM
#25
Looking good Karlos, sounds like a headfuck to me but im glad you got it fitted.
Have you given you boost controller a re-set... is it self learning? could it be interfering etc.?
Sounds like a sweet idea mate, a water bath would be the simplest method of cooling, and if necessary and pump/rad/fan.
And you could get a random power reading, which would at least let you see if you were making more power/less power with a map/timing change.
Random power reading will come from the energy needed to maintain a constant speed, or from a constant load vs rate of increase of speed of rollers (probably).
The only thing you wouldn't be able to do if give a BHP/KW figure.
Rob.
Have you given you boost controller a re-set... is it self learning? could it be interfering etc.?
Try advancing the cam timing a little if you suspect that as the problem Karlos.
I was looking into building a dyno as apparently, to brake the engine via eddy current is quite easy. To keep the motor that you use to brake the engine cool is another matter! That would be ok for loading engines up and down for mapping purposes but wouldn't give any power figures.
I was looking into building a dyno as apparently, to brake the engine via eddy current is quite easy. To keep the motor that you use to brake the engine cool is another matter! That would be ok for loading engines up and down for mapping purposes but wouldn't give any power figures.
And you could get a random power reading, which would at least let you see if you were making more power/less power with a map/timing change.
Random power reading will come from the energy needed to maintain a constant speed, or from a constant load vs rate of increase of speed of rollers (probably).
The only thing you wouldn't be able to do if give a BHP/KW figure.
Rob.
30-06-2011, 09:52 PM
#26
Norris Motorsport
Hello,
A 60 trim compressor wheel and basic 1600cc engine generally surge above about 18 psi. The correct compressor wheel for that spec engine on a 0.48 turbine is preferably a 50 trim if you want a BIG mid range boost spike without surge, or a 55 trim for a recommended held 22psi. The 60 trim compressor wheel is I'm affraid a very poor wheel in general.
The only other option is to use a different cam, but assuming everything else is correct, essentially you've got the wrong spec turbo!
A 60 trim compressor wheel and basic 1600cc engine generally surge above about 18 psi. The correct compressor wheel for that spec engine on a 0.48 turbine is preferably a 50 trim if you want a BIG mid range boost spike without surge, or a 55 trim for a recommended held 22psi. The 60 trim compressor wheel is I'm affraid a very poor wheel in general.
The only other option is to use a different cam, but assuming everything else is correct, essentially you've got the wrong spec turbo!
30-06-2011, 11:25 PM
#27
Hello karlos,
At what rpm was the boost surging?
With the electronic boost controller you should be able to tailor the boost curve
vs. RPM.
You should be able to plot your engine airflow demand on the 60 trim compressor map you posted.
Also take a look at this turbo calculator: http://www.squirrelpf.com/turbocalc/index.php
It is quite good.
I input a 1.6 engine, and 250 hp, and .55 bsfc, and 1 psi intercooler boost loss.
I also mapped the 60 trim T3 with these parameters.
It looks like 4000 rpm before you can be at full boost (over 18 psi)
Cheers
At what rpm was the boost surging?
With the electronic boost controller you should be able to tailor the boost curve
vs. RPM.
You should be able to plot your engine airflow demand on the 60 trim compressor map you posted.
Also take a look at this turbo calculator: http://www.squirrelpf.com/turbocalc/index.php
It is quite good.
I input a 1.6 engine, and 250 hp, and .55 bsfc, and 1 psi intercooler boost loss.
I also mapped the 60 trim T3 with these parameters.
It looks like 4000 rpm before you can be at full boost (over 18 psi)
Cheers
I will try mate!
Hello,
A 60 trim compressor wheel and basic 1600cc engine generally surge above about 18 psi. The correct compressor wheel for that spec engine on a 0.48 turbine is preferably a 50 trim if you want a BIG mid range boost spike without surge, or a 55 trim for a recommended held 22psi. The 60 trim compressor wheel is I'm affraid a very poor wheel in general.
The only other option is to use a different cam, but assuming everything else is correct, essentially you've got the wrong spec turbo!
A 60 trim compressor wheel and basic 1600cc engine generally surge above about 18 psi. The correct compressor wheel for that spec engine on a 0.48 turbine is preferably a 50 trim if you want a BIG mid range boost spike without surge, or a 55 trim for a recommended held 22psi. The 60 trim compressor wheel is I'm affraid a very poor wheel in general.
The only other option is to use a different cam, but assuming everything else is correct, essentially you've got the wrong spec turbo!
The engine is a stock CR 1600cc with forged internals, you worked my head for me (stock valve size, but stainless with bronze guides), a newmans off the shelf RST cam and lifters, stock valve springs, and stock manifolds but I have a custom inlet on it's way!
Last edited by Karlos G; 30-06-2011 at 11:28 PM.
30-06-2011, 11:48 PM
#28
Norris Motorsport
Karlos,
Changing manifolds will not help I'm affraid! The problem is that your engine is only 1600cc with a 60 trim compressor! You need to make some quite serious VE changes to make a 60 trim work on a 1600cc.
If after you have tried all your basic adjustments (less actuator preload gives less surge, NOT more preload as advised!!!) I would simply change compressor to a 55trim, as you're wasting your time with the 60trim!
Changing manifolds will not help I'm affraid! The problem is that your engine is only 1600cc with a 60 trim compressor! You need to make some quite serious VE changes to make a 60 trim work on a 1600cc.
If after you have tried all your basic adjustments (less actuator preload gives less surge, NOT more preload as advised!!!) I would simply change compressor to a 55trim, as you're wasting your time with the 60trim!
01-07-2011, 08:24 AM
#29
Ok thanks for that Karl, wish I'd known that in the first place! 
lol
I will try a little less preload, I will also have a vernier in a day or two so will adjust the cam timing to see if it helps, I know advancing will lower the power band and retarding it will raise the power band... But what would be better to help reduce surge Karl?
lolI will try a little less preload, I will also have a vernier in a day or two so will adjust the cam timing to see if it helps, I know advancing will lower the power band and retarding it will raise the power band... But what would be better to help reduce surge Karl?
02-07-2011, 02:19 AM
#37
Too many posts.. I need a life!!
Hello Karlos,
One relatively simple test would be to remove the electronic boost controller altogether.
Replace it with a manual boost valve - or just use the actuator itself.
It would be most interesting to see what happens with only the wastegate actuator plumbed to turbo boost.
One relatively simple test would be to remove the electronic boost controller altogether.
Replace it with a manual boost valve - or just use the actuator itself.
It would be most interesting to see what happens with only the wastegate actuator plumbed to turbo boost.
02-07-2011, 09:32 AM
#38
What are you thinking Rick?
Yeah it is! Very good to see tuners offering advice on here.
Yes mate and by that I mean the engine will not consume any more air, the VE table's maximum value is identical to that of the previous turbo (albeit at 10psi less boost pressure) so I think that points to something other than the turbo maybe...
Yes I could try that!
Yeah it is! Very good to see tuners offering advice on here.
Hello Karlos,
One relatively simple test would be to remove the electronic boost controller altogether.
Replace it with a manual boost valve - or just use the actuator itself.
It would be most interesting to see what happens with only the wastegate actuator plumbed to turbo boost.
One relatively simple test would be to remove the electronic boost controller altogether.
Replace it with a manual boost valve - or just use the actuator itself.
It would be most interesting to see what happens with only the wastegate actuator plumbed to turbo boost.
Last edited by Karlos G; 02-07-2011 at 09:35 AM.
