My New Spec...
#81
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In theory, in the same way (I posted up where the measurement on the dyno was taken from in my original post, so there could be no confusion, but obviously I didn't allow for you ) - the only difference being, you wouldn't be able to hold the load site you were measuring very easily on the road (would require left foot breaking etc).
do you have to have a boss welded to the manifold? or is a probe inserted somewhere? ()........
Can it be shown on someone's dyno pictures?
#99
Norris Motorsport
Hi Mike,
Interesting results from the engine dyno. Here are some of my thoughts....
1. Wastegate is returning to main exhaust. I have never done this, and find the 0.63 and 0.82 housings VERY similar for back pressure, where as on harveys dyno the two are clearly different.........however the power is very similar, exaclty as I have found.
2. The chances are my test engine had a considerably better head and cam setup than the dyno engine, and my engine revs to 8800rpm! We have held it sustained at 8500rpm whilst mapping with no issues. The engine in question is the sunbeam engine and is essentially a 700bhp engine running a GT30.
3. The dyno results in no way reflect the road characteristcs of the two turbos. The 0.82 is more laggy and lazy.
4. For thoroughness of testing I will bolt a normal 500bhp head to the sunbeam engine and retest back pressure readings and let you know what I find.
5. 137mph qtr mile terminal speeds with the 0.63 GT30 and no NOS shows its hardly down on power regardless of whether you believe the 530bhp claim! LOL
Interesting results from the engine dyno. Here are some of my thoughts....
1. Wastegate is returning to main exhaust. I have never done this, and find the 0.63 and 0.82 housings VERY similar for back pressure, where as on harveys dyno the two are clearly different.........however the power is very similar, exaclty as I have found.
2. The chances are my test engine had a considerably better head and cam setup than the dyno engine, and my engine revs to 8800rpm! We have held it sustained at 8500rpm whilst mapping with no issues. The engine in question is the sunbeam engine and is essentially a 700bhp engine running a GT30.
3. The dyno results in no way reflect the road characteristcs of the two turbos. The 0.82 is more laggy and lazy.
4. For thoroughness of testing I will bolt a normal 500bhp head to the sunbeam engine and retest back pressure readings and let you know what I find.
5. 137mph qtr mile terminal speeds with the 0.63 GT30 and no NOS shows its hardly down on power regardless of whether you believe the 530bhp claim! LOL
Last edited by Karl; 10-04-2008 at 11:13 AM.
#100
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2. The chances are my test engine had a considerably better head and cam setup than the dyno engine, and my engine revs to 8800rpm! We have held it sustained at 8500rpm whilst mapping with no issues. The engine in question is the sunbeam engine and is essentially a 700bhp engine running a GT30.
Ben
#101
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Hi Mike,
Interesting results from the engine dyno. Here are some of my thoughts....
Hoped you would reply, as I am always interested to see your findings, as they seem to be based on actual testing .
1. Wastegate is returning to main exhaust. I have never done this, and find the 0.63 and 0.82 housings VERY similar for back pressure, where as on harveys dyno the two are clearly different.........however the power is very similar, exaclty as I have found.
What effect do you think that feeding the wastegate into the exhaust will have? Are you measuring the back pressure in the same place? How are you measuring the back pressure (from a load site point of view)? I was surprised that given the back pressure disparity that the power was so similar .
2. The chances are my test engine had a considerably better head and cam setup than the dyno engine, and my engine revs to 8800rpm! We have held it sustained at 8500rpm whilst mapping with no issues. The engine in question is the sunbeam engine and is essentially a 700bhp engine running a GT30.
I don't doubt that for a second, as Paul's engine only has a medium port head, standard size valves, 2wd exhaust and EECIV inlet. Given your above statement, it seems unusual for you to claim 530-540bhp from an engine that is way off the air flow of your test engine, along with having the wastegate connected in a way that yours wasn't?
3. The dyno results in no way reflect the road characteristcs of the two turbos. The 0.82 is FAR more laggy and lazy. The 0.63 wins hands down EVERYWHERE.
I agree, you can't see anything other than improvements in boost threshold on the dyno (although you get a basic idea of what it "should" do from experience). The 0.63 a/r turbo is the one to have for a road engine, but I would be concerned at the back-pressure readings for one that is going to be used either extensively on track or in top speed running.
4. For thoroughness of testing I will bolt a normal 500bhp head to the sunbeam engine and retest back pressure readings and let you know what I find.
That would be very interesting to see - don't forget to use a standard inlet and exhaust manifold for direct comparisons .
5. 137mph qtr mile terminal speeds with the 0.63 GT30 and no NOS shows its hardly down on power regardless of whether you believe the 530bhp claim! LOL
That is very impressive, but without knowing the weight of the car, doesn't give any indication of power to weight to get a better picture of exactly HOW impressive . Can your reveal this?
In the meantime, thanks for taking part in this discussion, as it is always interesting when you are involved - especially when you are imparting technical details .
Interesting results from the engine dyno. Here are some of my thoughts....
Hoped you would reply, as I am always interested to see your findings, as they seem to be based on actual testing .
1. Wastegate is returning to main exhaust. I have never done this, and find the 0.63 and 0.82 housings VERY similar for back pressure, where as on harveys dyno the two are clearly different.........however the power is very similar, exaclty as I have found.
What effect do you think that feeding the wastegate into the exhaust will have? Are you measuring the back pressure in the same place? How are you measuring the back pressure (from a load site point of view)? I was surprised that given the back pressure disparity that the power was so similar .
2. The chances are my test engine had a considerably better head and cam setup than the dyno engine, and my engine revs to 8800rpm! We have held it sustained at 8500rpm whilst mapping with no issues. The engine in question is the sunbeam engine and is essentially a 700bhp engine running a GT30.
I don't doubt that for a second, as Paul's engine only has a medium port head, standard size valves, 2wd exhaust and EECIV inlet. Given your above statement, it seems unusual for you to claim 530-540bhp from an engine that is way off the air flow of your test engine, along with having the wastegate connected in a way that yours wasn't?
3. The dyno results in no way reflect the road characteristcs of the two turbos. The 0.82 is FAR more laggy and lazy. The 0.63 wins hands down EVERYWHERE.
I agree, you can't see anything other than improvements in boost threshold on the dyno (although you get a basic idea of what it "should" do from experience). The 0.63 a/r turbo is the one to have for a road engine, but I would be concerned at the back-pressure readings for one that is going to be used either extensively on track or in top speed running.
4. For thoroughness of testing I will bolt a normal 500bhp head to the sunbeam engine and retest back pressure readings and let you know what I find.
That would be very interesting to see - don't forget to use a standard inlet and exhaust manifold for direct comparisons .
5. 137mph qtr mile terminal speeds with the 0.63 GT30 and no NOS shows its hardly down on power regardless of whether you believe the 530bhp claim! LOL
That is very impressive, but without knowing the weight of the car, doesn't give any indication of power to weight to get a better picture of exactly HOW impressive . Can your reveal this?
In the meantime, thanks for taking part in this discussion, as it is always interesting when you are involved - especially when you are imparting technical details .
#102
Caraholic
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The engine is gradually built up to the rpm load site (both revs and boost wise) and once satisfied that everything is safe, a few seconds are waited for it to stabilise and then the "run" recorded. I would say the total length of time it takes from start to finish of each load site run is no more than 10-12s.
#103
Norris Motorsport
Hi Mike,
Regards comparing AJC's engine in terms of power to our sunbeam engine, the reason I estimated his power to be around 530bhp is because he uses the same 83lb siemens injectors and 5 bar map sensor on a L8 ecu as in our car. Hence comparing his fuel map to our sunbeam engine his engine is VERY similar in injector durations up to 7300rpm, (He also runs the same fuel pressure which was monitored during mapping) which is where the engine will be making peak power.
Back pressure readings are taken at the entrance of turbine housing.
I believe the external plumbing of the wastegate makes an improvement on back pressure BUT until tested that is only heresay and my opinion.
Regards comparing AJC's engine in terms of power to our sunbeam engine, the reason I estimated his power to be around 530bhp is because he uses the same 83lb siemens injectors and 5 bar map sensor on a L8 ecu as in our car. Hence comparing his fuel map to our sunbeam engine his engine is VERY similar in injector durations up to 7300rpm, (He also runs the same fuel pressure which was monitored during mapping) which is where the engine will be making peak power.
Back pressure readings are taken at the entrance of turbine housing.
I believe the external plumbing of the wastegate makes an improvement on back pressure BUT until tested that is only heresay and my opinion.
Last edited by Karl; 10-04-2008 at 11:14 AM.
#104
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as you know Karl Pauls engine made just shy of 500hp on the dyno with no ancilirys so in car its going to be even less where are you quoting 530hp for andys engine in car as that would mean 550ish hp on a Dyno? do you put the extra 50hp down to your cam choice and head work?
thanks
thanks
#105
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Best thread on here for a long time, I am learning so much info that will no doubt have a direct impact on the choices I make in the future. Cheers guys.
#106
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Hi Mike,
Regards comparing AJC's engine in terms of power to our sunbeam engine, the reason I estimated his power to be around 530bhp is because he uses the same 83lb siemens injectors and 5 bar map sensor on a L8 ecu as in our car. Hence comparing his fuel map to our sunbeam engine his engine is VERY similar in injector durations up to 7300rpm, (He also runs the same fuel pressure which was monitored during mapping) which is where the engine will be making peak power. (Our sunbeam makes 537bhp at 7300rpm). The big difference comes after 7300 where AJC's power falls away steadily where as believe it or not our sunbeam still has over 500bhp at the 8800rpm limiter! (Amazing for a GT30 which is well out of puff at 8800)
Back pressure readings are taken at the entrance of turbine housing.
I believe the external plumbing of the wastegate makes a SIGNIFICANT improvement on back pressure BUT until tested that is only heresay and my opinion.
Regards comparing AJC's engine in terms of power to our sunbeam engine, the reason I estimated his power to be around 530bhp is because he uses the same 83lb siemens injectors and 5 bar map sensor on a L8 ecu as in our car. Hence comparing his fuel map to our sunbeam engine his engine is VERY similar in injector durations up to 7300rpm, (He also runs the same fuel pressure which was monitored during mapping) which is where the engine will be making peak power. (Our sunbeam makes 537bhp at 7300rpm). The big difference comes after 7300 where AJC's power falls away steadily where as believe it or not our sunbeam still has over 500bhp at the 8800rpm limiter! (Amazing for a GT30 which is well out of puff at 8800)
Back pressure readings are taken at the entrance of turbine housing.
I believe the external plumbing of the wastegate makes a SIGNIFICANT improvement on back pressure BUT until tested that is only heresay and my opinion.
Goes to show how good your head is, as I know what had to be done to mine to achieve 500bhp @ 8500rpm .
Thanks for taking the time
#107
Norris Motorsport
Gatecrasher,
Yes there is no doubt the heads and cams on my 530bhp GT30 engines are better flowing than the 500bhp engine of pauls. My engines usually run solid lifter cams.
Beyond 7000rpm the GT30 cannot maintain boost, and is normally down to 1.8bar by 8000rpm where I usually see around 500bhp. The GT35 can however still pull 2.3bar at 8000rpm, normally showing power around 580bhp.
Again all this testing is on my own engines are EVERYTHING is monitered and tested including individual EGT'S.
Hope that info is helpfull.
Yes there is no doubt the heads and cams on my 530bhp GT30 engines are better flowing than the 500bhp engine of pauls. My engines usually run solid lifter cams.
Beyond 7000rpm the GT30 cannot maintain boost, and is normally down to 1.8bar by 8000rpm where I usually see around 500bhp. The GT35 can however still pull 2.3bar at 8000rpm, normally showing power around 580bhp.
Again all this testing is on my own engines are EVERYTHING is monitered and tested including individual EGT'S.
Hope that info is helpfull.
Last edited by Karl; 10-04-2008 at 11:10 AM.
#108
Norris Motorsport
Mike,
All measurement is done whilst mapping. To sustain load at say 8500rpm we load the car fully in 4th and hold the engine back on the brakes to maintain load at that particualr rpm. Obviously this is real world testing, and NOT the artifical dyno environment which can be VERY misleading.
Power readings are from Nobles, so of course are speculative, but I have sufficient experience of mapping and comparing specific map data to understand the effects and consequences of changes made whilst testing out on the road and thus can accurately quantify power gained or lost by comparing injection duration times on the same engine.
All measurement is done whilst mapping. To sustain load at say 8500rpm we load the car fully in 4th and hold the engine back on the brakes to maintain load at that particualr rpm. Obviously this is real world testing, and NOT the artifical dyno environment which can be VERY misleading.
Power readings are from Nobles, so of course are speculative, but I have sufficient experience of mapping and comparing specific map data to understand the effects and consequences of changes made whilst testing out on the road and thus can accurately quantify power gained or lost by comparing injection duration times on the same engine.
#110
Caraholic
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Karl,
Perfectly adequate explanation - thanks for taking the time to post .
Obviously the only disparity we have are the power figures (but that is always the case conparing a rolling road's artificially calculated flywheel figures with engine dyno figures) and the back pressure readings (clarified by yourself) . Everything else we seem to be in agreement on.
A real shame that a run without the wastegate connected to the exhaust wasn't carried out on the dyno, as that may have shown a measured difference in back-pressure readings, as it would make sense for there to be less back pressure with a screamer pipe .
That leaves another experiment to carry out on a different day .
Very interesting comment you have made about the GT35 .
Perfectly adequate explanation - thanks for taking the time to post .
Obviously the only disparity we have are the power figures (but that is always the case conparing a rolling road's artificially calculated flywheel figures with engine dyno figures) and the back pressure readings (clarified by yourself) . Everything else we seem to be in agreement on.
A real shame that a run without the wastegate connected to the exhaust wasn't carried out on the dyno, as that may have shown a measured difference in back-pressure readings, as it would make sense for there to be less back pressure with a screamer pipe .
That leaves another experiment to carry out on a different day .
Very interesting comment you have made about the GT35 .
#111
Caraholic
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Would be interesting to see if Martin and Karl agree .
#118
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edited to say after re-reading Karl's post that power could be had above 7500 on solids compared to hydraulics.
Last edited by rapidcossie; 09-04-2008 at 08:04 PM.
#119
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