What Engine for 500BHP
Discussion
stevieturbo said:
Can you show boost and ex manifold pressure on same screen, and same scaling only ?
It's very hard to make out any units or scaling on that screenshot.
Wherever your cursor is says manifold pressure is 40 and exhaust 86 ?
None of those units make any sense.
Edit.
I presume the scaling on the left covers both ? ie boost is around 180 or so ? so EGBP around 240 ?
I guess that's 0.8bar positive, and 1.4bar positive ?
If you want a smoother graph, either mechanically filter it, or I'm sure you can filter that channel in the log viewer.
Given how laggy it appears to be I'm surprised EGBP is that high, but in real terms it isnt so high it's of any concern at all.
Ok Here it is again:It's very hard to make out any units or scaling on that screenshot.
Wherever your cursor is says manifold pressure is 40 and exhaust 86 ?
None of those units make any sense.
Edit.
I presume the scaling on the left covers both ? ie boost is around 180 or so ? so EGBP around 240 ?
I guess that's 0.8bar positive, and 1.4bar positive ?
If you want a smoother graph, either mechanically filter it, or I'm sure you can filter that channel in the log viewer.
Given how laggy it appears to be I'm surprised EGBP is that high, but in real terms it isnt so high it's of any concern at all.
Edited by stevieturbo on Thursday 29th October 17:59
MAP, Boost Target & EBP are 50-300kpa
rpm 0-7000
throttle 0-100%
And I have stuck the cursor where you can see it. 6950rpm - Map =195kpa (0.95bar) EBP = 257kpa (1.57bar) so pretty close to what you interpreted from the first graph.
What would you consider too high for Exhaust pressure?
stevieturbo said:
Do you have adjustable camwheels ? And can they be adjusted easily ?
Rather than spending money on cams, it could be worth playing with them on the dyno.
Stevie - the cams are not easily adjustable. The cam wheel/cam connection is a taper, with no key, so could be adjusted, but not something easily done, especially time wise on a RR.Rather than spending money on cams, it could be worth playing with them on the dyno.
Evoluzione said:
R8VXF said:
On the subject of the cam, all I really think I know is that for boosted applications you need little to no overlap between intake and exhaust valve opening to allow the turbo/supercharger to actually pressurise the cylinder, whereas NA you need the overlap to help keep the air flowing. I would look into seeing if you can get a CAM designed for boost IMO, will improve the engine a lot.
That's completely incorrect. You treat a performance turbo engine with a sizeable turbo just like you would a performance NA when it comes to cams.Neil the cams in your engine are pathetic! It must be like driving a car with small electric motor - it gets there eventually, just very smoothly and slowly. The tricky bit would be introducing more power without it happening all at once and throwing you sideways, so I guess a mild cam upgrade coupled with your trick boost control would work well. It would be too easy to let loose with big power and make a car which is vicious to drive.
More power I dont need! If I wind up the boost to 1.5 bar , I would expect to see around 600BHP, which is more than the rest of the driveline can handle. So as the thread title, I have now decided to stick with around 500BHP, what I am looking for is to get the boost earlier to get better driveability...
All suggestions are welcome...
stevieturbo said:
If you can get a turbo with similar turbine flow and much smaller lighter compressor, it should spool up a lot faster, but still be efficient on the turbine side too.
Maybe try and pick up a GT30 second hand ? Although probably need to buy the turbine hosing new to suit your V-Band unless you're lucky to find one.
The GT30 1.06 a/r housing has pretty much the same flow as the gt35 0.82 housing, so that should work. There is one for sale, with a tial housing in the USA now, but the guy selling it dosent know what a/r the housing is!!!Maybe try and pick up a GT30 second hand ? Although probably need to buy the turbine hosing new to suit your V-Band unless you're lucky to find one.
andygtt said:
What is the power curve like on a stock engine thats not turbocharged?
Despite the lower CR Id expect your power curve to be better than the NA everywhere and just have it increase when boost comes on.... if the stock engine doesn't have much power low down its going to be hard to change that dynamic pre turbo spool.
I will have to look for one, as I cant find it at present....Despite the lower CR Id expect your power curve to be better than the NA everywhere and just have it increase when boost comes on.... if the stock engine doesn't have much power low down its going to be hard to change that dynamic pre turbo spool.
stevieturbo said:
turbonutter said:
Stevie - the cams are not easily adjustable. The cam wheel/cam connection is a taper, with no key, so could be adjusted, but not something easily done, especially time wise on a RR.
Can you get vernier pulleys for them though ? to make it easily adjustable ?R8VXF said:
On the subject of the cam, all I really think I know is that for boosted applications you need little to no overlap between intake and exhaust valve opening to allow the turbo/supercharger to actually pressurise the cylinder, whereas NA you need the overlap to help keep the air flowing. I would look into seeing if you can get a CAM designed for boost IMO, will improve the engine a lot.
It really depends. If the system does see much higher pressure in the exhaust manifold, then yes. You dont really want any overlap for obvious reasons. But as it also depends how well heads etc flow, rpm's etc etc there is no easy answer.Well there is, cams with little or no overlap will always be safe and capable of great drive ability and good power. The worst thing you'll ever do on a turbo engine is go too big with the cams. Usually that just hurts low end drive ability, spool, torque.....all for very little if any real gain up top, and can just shift the power band upwards, often without actually making you go any faster.
the more efficient you can make the build, the closer to 1:1 EGBP vs Manifold pressure...the more you can push with the cams without worry of it turning the car into a piece of s
t to drive.His cams are fine though, it isnt an all out race engine, but it would be nice to be able to play with the timing a bit if it could be done easily.
Maybe advance the exhaust cam a bit to try, might make it spool a little earlier.
But the GT30 sounds like a good plan.
Think I will keep mye eye out for a GT3076...
chuntington101 said:
Is there an alternative to the GT30 that could be had for less money? Anything from BW or Precision? Or maybe someone could rebuild the current turbo with a GT30 compressor?
I have also heard that a bigger turbine wheel with a tighter AR can net both spool and power gains. Might be worth seeing if a tighter AR would help. Also what about the size of the headers / cross over? Is there any room to make either smaller to increase velocity?
I want to stick to the GT range as, if I use the tial housing, it will be a direct swap....I have also heard that a bigger turbine wheel with a tighter AR can net both spool and power gains. Might be worth seeing if a tighter AR would help. Also what about the size of the headers / cross over? Is there any room to make either smaller to increase velocity?
Seen one for sale at the moment, but it has the 0.82 tial housing.. I think the 1.02 would be better as its closer to what I have with the 0.82 on my gt35
stevieturbo said:
If it comes with that housing, I'd just try it like that anyway. No sense spending extra money without trying it.
I guess the cam verniers not such a good idea lol.
There arent so many sellers of the likes of BW etc, and by time you by abroad with all duties etc, prob not much in it. The Garrett's are all over the place so not overly expensive.
Only big downside with them, if there is a problem they're effectively scrap as they cannot be rebuilt.
Whilst it'd probably be too small, and it's on a regular T3 flanges etc, I've a new Turbonetics GTK-550 here that was never used. Probably wouldnt cost a fortune.
Not sure if it's interchangeable with the Tial T3 housings or not.
A friend bought it years ago and never used it.
I was thinking along the same lines - try the 3076 with the 0.82a/r if it needed a bigger housing, I wouldnt have lost anything!I guess the cam verniers not such a good idea lol.
There arent so many sellers of the likes of BW etc, and by time you by abroad with all duties etc, prob not much in it. The Garrett's are all over the place so not overly expensive.
Only big downside with them, if there is a problem they're effectively scrap as they cannot be rebuilt.
Whilst it'd probably be too small, and it's on a regular T3 flanges etc, I've a new Turbonetics GTK-550 here that was never used. Probably wouldnt cost a fortune.
Not sure if it's interchangeable with the Tial T3 housings or not.
A friend bought it years ago and never used it.
No vernier pulleys not so great....
I would have to look into the gtk550, but doubt it would fit the tial housing ....
Evoluzione said:
I'll list them. Port flows we are going to struggle with I assume?
Bore
stroke
Rod length
Pin offset
Static CR
Valve diameters and min port CSA of in & ex
Port flow at a range of valve lifts
Direct acting or rockers?
Intake runner length from valve to entry in plenum
Runner entry area
Port min CSA
Throttle blade size
Turbo name and spec
Ex manifold int' dia'
Tube length
Collector length, entry area and exit area.
Do you have your latest power figures in a table format rather than graph?
Do you have the power figures for an original untouched N/A engine? The more explicit the better.
Most of that I can get, but it will take a while... Port flows as you suspect I dont have, also min pors CSA will be difficult.Bore
stroke
Rod length
Pin offset
Static CR
Valve diameters and min port CSA of in & ex
Port flow at a range of valve lifts
Direct acting or rockers?
Intake runner length from valve to entry in plenum
Runner entry area
Port min CSA
Throttle blade size
Turbo name and spec
Ex manifold int' dia'
Tube length
Collector length, entry area and exit area.
Do you have your latest power figures in a table format rather than graph?
Do you have the power figures for an original untouched N/A engine? The more explicit the better.
The only thing I am not sure on what you mean is "PIN OFFSET"
also do you want just the power figures or torque as well
Edited by turbonutter on Saturday 31st October 22:26
Max_Torque said:
Before you spend ages messing around, get a psuedo steady state curve!
Ie, 4th gear, against the brakes on a long straight empty road (or chassis dyno), from 1000rpm upwards. Got WOT, use the brakes to drag you down to 1000rpm, slowly let the rpm increase. If you can do it uphill it helps too. You only need to go to the revs where boost is fully built, so probably 3.5krpm ish. This steady state curve can then be compared to the dynamic curve and you'll see if it's a turbo inertia issue or a sizing one.
You can also play around with the ignition angle at low rpms, trade off some off-boost torque for more turbine energy to get it started earlier. Remember, turbo's are positive feedback devices. More boost = more air = more fuel = more exhaust energy = more boost etc etc. Small changes in exhaust energy at say 2000rpm can massively affect the fully spooled point!
That sounds like a reasonable test to make, will try to get it done this week... Ie, 4th gear, against the brakes on a long straight empty road (or chassis dyno), from 1000rpm upwards. Got WOT, use the brakes to drag you down to 1000rpm, slowly let the rpm increase. If you can do it uphill it helps too. You only need to go to the revs where boost is fully built, so probably 3.5krpm ish. This steady state curve can then be compared to the dynamic curve and you'll see if it's a turbo inertia issue or a sizing one.
You can also play around with the ignition angle at low rpms, trade off some off-boost torque for more turbine energy to get it started earlier. Remember, turbo's are positive feedback devices. More boost = more air = more fuel = more exhaust energy = more boost etc etc. Small changes in exhaust energy at say 2000rpm can massively affect the fully spooled point!
So Here is a stock GTA Power Curve.
and here a comparison.
Curves from:
AET Hub Dyno (wheel power) when running 1.3 bar
John Sleath's rolling road (Flywheel Figures) running 1.0 bar
& the stock figures.
Not perfect comparisons as the AET plots start at lower rpm & the figures at 1 bar on the RR, had briefly helt the rpm at 3000 before the pull..
Unfortunately I just had a call from work & there are some issues on my ship, so I have to go back in a coupl eof days, a few feeks earlier than planned, so there wont be any chance to do any testing
and here a comparison.
Curves from:
AET Hub Dyno (wheel power) when running 1.3 bar
John Sleath's rolling road (Flywheel Figures) running 1.0 bar
& the stock figures.
Not perfect comparisons as the AET plots start at lower rpm & the figures at 1 bar on the RR, had briefly helt the rpm at 3000 before the pull..
Unfortunately I just had a call from work & there are some issues on my ship, so I have to go back in a coupl eof days, a few feeks earlier than planned, so there wont be any chance to do any testing
andygtt said:
Ok you don't look horrific compared to the standard NA engine.
Maybe its worth mentioning that the standard noble 3.0L engine had completely standard cams with just shorter rods to lower the CR... however the cam timing on the exhaust cams was set back a single tooth.. forgetting the technical arguments about this what it actually did on all the cars was drop the power band back 500rpm giving more low down power but it tailed off similar place to yours.
Maybe this is an avenue for you to research while on the vessel?
As I say the Ford V6 is very similar to yours and Noble turbocharged it so you might be able to use this engine as a loose baseline to compare especially cam timing?
Definately worth comparing the Noble engine specs with my engine, I have planty of time, so will try to investigate as many options as I can...Maybe its worth mentioning that the standard noble 3.0L engine had completely standard cams with just shorter rods to lower the CR... however the cam timing on the exhaust cams was set back a single tooth.. forgetting the technical arguments about this what it actually did on all the cars was drop the power band back 500rpm giving more low down power but it tailed off similar place to yours.
Maybe this is an avenue for you to research while on the vessel?
As I say the Ford V6 is very similar to yours and Noble turbocharged it so you might be able to use this engine as a loose baseline to compare especially cam timing?
Thanks thats what I thought. I assume the actual turbine wheel temperature is hotter than measured by the EGT probe, so 950C would be a reasonable max limit to use. What little logging I have of the EGT's I am pretty close & that was with 15C ambient temperatures, So I may have to look at Water Injection - Will see how the temperatures look when we get some warm weather
Edited by turbonutter on Thursday 19th November 16:31
Finally after being home 2 months, I managed to find time to get the car to the MOT station & back on the road.
Did a quicl logging session for temperatures & have found with an ambient temp of 10-12C, I am getting 38C inlet air temp & 950C EGT before the turbo, obviously this will increase when summer finally comes along, so I am looking at fitting some water injection.
I was thinking of using a Devils Own Progressive Kit: http://www.methanol-injection.co.uk/index.php?rout...
Anyone got any thoughts on which Water injection kit to use???
Did a quicl logging session for temperatures & have found with an ambient temp of 10-12C, I am getting 38C inlet air temp & 950C EGT before the turbo, obviously this will increase when summer finally comes along, so I am looking at fitting some water injection.
I was thinking of using a Devils Own Progressive Kit: http://www.methanol-injection.co.uk/index.php?rout...
Anyone got any thoughts on which Water injection kit to use???
I saw the 950C a number of times accelerating 2nd,3rd,4th,5th...
I had a thermocouple at work, with an amplifier and used our dryblock temperature calibrator to see hoe they worked and upto 500C (max for out calibrator) the reading on the calibrator agreed with the amplifier output +/- 5C, so I would guess they are reasonably accurate..
Of course Aquamist, I was thinking the company was cooling mist..... Definately the system they have looks better, as it has the failsafes & monitors the flow, so will detect clogged nozzles etc...Its probably worth the extra for this function.
I had a thermocouple at work, with an amplifier and used our dryblock temperature calibrator to see hoe they worked and upto 500C (max for out calibrator) the reading on the calibrator agreed with the amplifier output +/- 5C, so I would guess they are reasonably accurate..
Of course Aquamist, I was thinking the company was cooling mist..... Definately the system they have looks better, as it has the failsafes & monitors the flow, so will detect clogged nozzles etc...Its probably worth the extra for this function.
stevieturbo said:
AEM sell a flow meter with a 0-5v output.
This could be used to feed into an ecu for either safety purposes or an actual load parameter to make fuel/timing adjustments.
Only caveat with a flow meter is a burst pipe would see flow, but not into the engine. ( rare scenario though )
If it monitored flow and pressure, which I think Aquamist does....it's fairly well covered.
Although if the ecu has good closed loop fuel adjustments and knock control, hopefully this too could catch any problems, or lean trips etc
Depends how much water/meth you want to use. If only small amounts to keep things a little cooler rather than pushing hard for more power, you could easily forego external safeties and maybe just spray a little water based on charge temps, EGT or whatever
ECU control would be by far easiest way for that if you had a couple of spare outputs. ie one for the pump and one for the control solenoid. Unless you choose to PWM the pump itself in which case only a single ecu output would be needed and a SSR or similar to carry the load.
I think the aquamist also monitors for excessive flow, i.e. burst pipe.....This could be used to feed into an ecu for either safety purposes or an actual load parameter to make fuel/timing adjustments.
Only caveat with a flow meter is a burst pipe would see flow, but not into the engine. ( rare scenario though )
If it monitored flow and pressure, which I think Aquamist does....it's fairly well covered.
Although if the ecu has good closed loop fuel adjustments and knock control, hopefully this too could catch any problems, or lean trips etc
Depends how much water/meth you want to use. If only small amounts to keep things a little cooler rather than pushing hard for more power, you could easily forego external safeties and maybe just spray a little water based on charge temps, EGT or whatever
ECU control would be by far easiest way for that if you had a couple of spare outputs. ie one for the pump and one for the control solenoid. Unless you choose to PWM the pump itself in which case only a single ecu output would be needed and a SSR or similar to carry the load.
At the moment I am just looking to cool things a little, but I guess ultimately I will want to add a few BHP as well, to get back to where i was before it blew up
You are right, I could quite easily use the ecu to do what the controller does, with a pwm table with boost or injector duty 'vs' air temp & with another to trigger the pump on. Safety wise I have knock control & can also take a chunk out of the boost solenoid base duty if the temp goes high, so that should cover it.
If I do it that way, then I could use a Devils own pump, with -4 Hose & their race tank, which is quite nice & just use a Aquamist Fast Acting valve for the control.... or skip the fast valve and pwm the pump via a SSR, depends what outputs I have available (i am sure I have plenty of spare ones)...
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