Which Turbo ?????
Discussion
Im looking to turbo charge an engine for a current project.
I have 2 of these engines sitting here in the workshop so this is the only way to go, another engine is not an option nor would any other engine suit this project.
Ok The stats are:
Vehicle Weight = 1000kg
Use = Fast Street, occasional track use
Manual Transmission, custom lightweight flywheel, ITB's, Aggressive Cam Schrick 264/264 Degree Duration.Custom Software and map.
Engine Code = BMW M70B50 300 BHP 5.0 V12 2 valve per cylinder (Head Flow Very Poor).
The compression ratio is 8.8:1, stroke is 75 mm (3.0 in) and bore is 84 mm (3.3 in).
I believe that all internals are strong enough as stock except for pistons. New ones on order specifically spec'd for forced induction.
Im looking for a good amount of power 550bhp minimum but it needs to be ready and available no lag, but not un-drivable wheels spinning everywhere etc. Progressive i think would be best way of describing it. Does this point toward single turbo?
What Turbo would you recommend? And would it be single or Twin turbo etc?
As the setup initially will be trial and error, im keen to keep costs down so ebay turbos etc that are from other vehicles would be ideal. Once im happy with the setup etc, we can spec the brand new all singing and dancing turbo.
thanks in advance.
I have 2 of these engines sitting here in the workshop so this is the only way to go, another engine is not an option nor would any other engine suit this project.
Ok The stats are:
Vehicle Weight = 1000kg
Use = Fast Street, occasional track use
Manual Transmission, custom lightweight flywheel, ITB's, Aggressive Cam Schrick 264/264 Degree Duration.Custom Software and map.
Engine Code = BMW M70B50 300 BHP 5.0 V12 2 valve per cylinder (Head Flow Very Poor).
The compression ratio is 8.8:1, stroke is 75 mm (3.0 in) and bore is 84 mm (3.3 in).
I believe that all internals are strong enough as stock except for pistons. New ones on order specifically spec'd for forced induction.
Im looking for a good amount of power 550bhp minimum but it needs to be ready and available no lag, but not un-drivable wheels spinning everywhere etc. Progressive i think would be best way of describing it. Does this point toward single turbo?
What Turbo would you recommend? And would it be single or Twin turbo etc?
As the setup initially will be trial and error, im keen to keep costs down so ebay turbos etc that are from other vehicles would be ideal. Once im happy with the setup etc, we can spec the brand new all singing and dancing turbo.
thanks in advance.
As it stands a new single turbo has been suggested borg warner turbo running in at £1400. Im just concerned with my lacking knowledge re speccing my system. I dont want lots of lag but I dont want it to be undriveable.
All that being said new turbos aren't essential. A good used pair from ebay would be fine. How do you spec them though?
All that being said new turbos aren't essential. A good used pair from ebay would be fine. How do you spec them though?
Edited by Mjpmark on Tuesday 29th October 23:12
Mjpmark said:
As it stands a new single turbo has been suggested borg warner turbo running in at £1400. Im just concerned with my lacking knowledge re speccing my system. I dont want lots of lag but I dont want it to be undriveable.
New simply opens up more options, albeit at higher cost. £1400 is excessive for a big single and relatively low overall power goal.From a UK supplier, this sort of thing is still good value, and would work fine as a single, and would spool quickly.
http://www.garagewhifbitz.co.uk/index.php/boostlab...
You could contact Boostlab in the US directly to enquire about specifics, or which turbine housing to use.
Or another option as a single, might be a GT4094R...although part of me only suggests it as I have a good used one for sale.
The BW unit above would for the most part be faster spooling though. The Garret is a ball bearing core which helps, but a larger heavier impeller, which goes against it slightly. But both are intended for similar power levels
Although you do mention "minimum" of 550....now that means an upper range of what ?
Either of the two above would work great I'd think. In no particular order, some US vendors
Obviously you can try UK vendors too, they usually tend to be a lot more expensive though, which is a shame.
Although the Whifbitz one I linked before is a good price for a UK seller.
http://www.precisionturbo.net/
http://www.theboostlab.com/store/
http://www.workturbochargers.com/
http://www.bullseyepower.com/home.asp
http://www.forcedinductions.com/
http://compturbo.com/
By all means contact them and see what they are suggesting.
Obviously you can try UK vendors too, they usually tend to be a lot more expensive though, which is a shame.
Although the Whifbitz one I linked before is a good price for a UK seller.
http://www.precisionturbo.net/
http://www.theboostlab.com/store/
http://www.workturbochargers.com/
http://www.bullseyepower.com/home.asp
http://www.forcedinductions.com/
http://compturbo.com/
By all means contact them and see what they are suggesting.
Mjpmark said:
another engine is not an option nor would any other engine suit this project
Ok The stats are:
Vehicle Weight = 1000kg
Use = Fast Street, occasional track use
Manual Transmission, custom lightweight flywheel, ITB's, Aggressive Cam Schrick 264/264 Degree Duration.Custom Software and map.
Engine Code = BMW M70B50 300 BHP 5.0 V12 2 valve per cylinder (Head Flow Very Poor).
The compression ratio is 8.8:1, stroke is 75 mm (3.0 in) and bore is 84 mm (3.3 in).
Sounds unrealistic... not saying it's not possible, but what is the purpose of ITBs if your going turbo? The turbo really takes the advantage away from the ITBs.Ok The stats are:
Vehicle Weight = 1000kg
Use = Fast Street, occasional track use
Manual Transmission, custom lightweight flywheel, ITB's, Aggressive Cam Schrick 264/264 Degree Duration.Custom Software and map.
Engine Code = BMW M70B50 300 BHP 5.0 V12 2 valve per cylinder (Head Flow Very Poor).
The compression ratio is 8.8:1, stroke is 75 mm (3.0 in) and bore is 84 mm (3.3 in).
Are you sure that no other engine would suit this project, or you would just rather not use another engine because you have already invested in this one.
All BMW V12s are heavy engines which is why they were never used in a M car. The one you listed will be roughly 1/4 of the listed vehicle weight once you have everything strapped up. I honestly believe there are a lot of better (and more conveniant) motors out there for your project. I also think you could save some money by choosing a different motor now and selling what you have.
However, I am not saying you are wrong for choosing this motor, it is a cool motor (and should be very smooth), but it will be a LOT of money/time and many projects like this get scrapped before they are completed. If this engine doesn't suit your needs, or you think you won't want to dedicate that kind of money/time to this project, you should stop now and make a change to save yourself a headache later. If you still feel like this is the engine for you, congratulations, and I look forward to hearing about your completed project.
As for turbos, I would pick a twinscrew supercharger instead, it will give better throttle response than most turbo setups and will likely be more reliable.
with turbos, cast manifolds, sump etc my stock BMW M70 V12 weighed under 180kgs... not light but for the configuration its hardly a heavyweight and is almost certainly not heavier than the E36 M3 engine because it doesn't have quad cams and an iron block.... The M3 head weighs more than the 2 V12 heads, I know as I have an M3 head as I was investigating fitting them to the V12.
Almost without doubt IMO the reason the V12 never ended in an M car is due to the size... please remember that this engine was used as a base for arguably the best super car ever made!
Almost without doubt IMO the reason the V12 never ended in an M car is due to the size... please remember that this engine was used as a base for arguably the best super car ever made!
The info given on the engine, including the ITB's are as the engine stands now.
A realistic re evaluation of the engine showed us that 500hp from a N/a M70b50 was far from realistic.
With turbos, the figure is certainly achievable and has been done many times.
This post was simply a way of trying to get more specific details on the turbos themselves. V12 as stated is simply the only engine for this project, at a relatively small cost of 1k to 1500 per engine the initial investment bares no reasoning to the continued use of the engine. It simply has to be this engine.
Ill keep you posted on the progression, Thanks Andy for all your info and Stevieturbo.
A realistic re evaluation of the engine showed us that 500hp from a N/a M70b50 was far from realistic.
With turbos, the figure is certainly achievable and has been done many times.
This post was simply a way of trying to get more specific details on the turbos themselves. V12 as stated is simply the only engine for this project, at a relatively small cost of 1k to 1500 per engine the initial investment bares no reasoning to the continued use of the engine. It simply has to be this engine.
Ill keep you posted on the progression, Thanks Andy for all your info and Stevieturbo.
It is fair comment about the ITB's
From a performance point of view, in this instance they would be a complete waste of money unless they're almost free.
As for the twin screw comment, not a chance of it being more reliable than a turbo setup.
If such blowers were the best and most reliable option, they would be mainstream on OEM.
They are not, and even OEM cars they are fitted too...rarely do any last half as long as a turbocharger on a similar engine. ( BMW turbo diesels excluded lol )
From a performance point of view, in this instance they would be a complete waste of money unless they're almost free.
As for the twin screw comment, not a chance of it being more reliable than a turbo setup.
If such blowers were the best and most reliable option, they would be mainstream on OEM.
They are not, and even OEM cars they are fitted too...rarely do any last half as long as a turbocharger on a similar engine. ( BMW turbo diesels excluded lol )
andygtt said:
with turbos, cast manifolds, sump etc my stock BMW M70 V12 weighed under 180kgs... not light but for the configuration its hardly a heavyweight and is almost certainly not heavier than the E36 M3 engine because it doesn't have quad cams and an iron block.... The M3 head weighs more than the 2 V12 heads, I know as I have an M3 head as I was investigating fitting them to the V12.
Almost without doubt IMO the reason the V12 never ended in an M car is due to the size... please remember that this engine was used as a base for arguably the best super car ever made!
All the M motors (powering M cars) of that era weigh under 150kgs. The M70 was lighter than the iron headed 6s but not the alloy headed 6s used in the M cars. Almost without doubt IMO the reason the V12 never ended in an M car is due to the size... please remember that this engine was used as a base for arguably the best super car ever made!
Even the McClaren motor which was loaded with lightweight parts (many of which were magnesium) weighed 166 kgs, and the weight reduction on that motor is fairly significant. If I remember correctly, it seems to me that a stock M70 weighed in at over 200kgs. In more recent years Alpina rejected BMW's newer V12 in favor of a V8 because the V12 was too heavy to be sporty.
Don't get me wrong here, but the McClaren engine was loosley based on the M70, it is more related to the formula motors that BMW was making at the time. Making this comparison is like comparing an LS1 to a C5R motor, they are totally different engines which were loosely based on the same block.
stevieturbo said:
It is fair comment about the ITB's
From a performance point of view, in this instance they would be a complete waste of money unless they're almost free.
As for the twin screw comment, not a chance of it being more reliable than a turbo setup.
If such blowers were the best and most reliable option, they would be mainstream on OEM.
They are not, and even OEM cars they are fitted too...rarely do any last half as long as a turbocharger on a similar engine. ( BMW turbo diesels excluded lol )
Most aftermarket setups are less reliable than twinscrew setups (this is assuming your pushing the same boost on an otherwise similarly matched setup). If the auto manufacturers were always looking for reliability, they wouldn't use variable valve technology or variable displacement technology, but both of these options are becoming more popular because of their benefits.From a performance point of view, in this instance they would be a complete waste of money unless they're almost free.
As for the twin screw comment, not a chance of it being more reliable than a turbo setup.
If such blowers were the best and most reliable option, they would be mainstream on OEM.
They are not, and even OEM cars they are fitted too...rarely do any last half as long as a turbocharger on a similar engine. ( BMW turbo diesels excluded lol )
The mainstream OEM turbos are popular because of increased fuel economy without loosing power. Look at Ford's ecoboost, Saabs old Ecopower, and even honda has a turbo 4 now (on a crossover SUV). Using a turbo you don't loose as much fuel economy at idle and lower throttle as with a twinscrew. Turbos are also popular because they don't rob as much power via drag.
To explain why I recommended a twinscrew over a turbo:
1. Regardless of your turbo setup there will be some lag, he indicated he wanted power on demand, while lag will be short on a well designed turbo setup, the twinscrew setup will deliver the power on demand.
2. Twinscrew setups are more efficient than roots setups at higher RPMs, but provide the advantages to a positive displacement blower.
3. Most setups are less prone to boost leaks, exhaust heat related problems (cracking mostly), significant amounts of oil leaking from the blower into the intake.
4. Most ultra high performance twinscrew setups are more street friendly than a turbo setup producing the same power.
As for the original poster, as I stated previously, it is not my goal to convince you to change your mind. I only hope to share my thoughts and insight with you. I am actually really excited to see this as it progresses (and I would like to follow your build if that is ok) because I actually find this project cool (because it isn't something that has been done a jazillion times).
Just another thought, not a common DIY builder choice, but a VGT would be super cool. The problem would be getting it to work right. I've only heard of one person who had success with a VGT in a DIY application and his setup had very limited VGT capabilities. Not saying you should try to put one of these on here, but if you want a superchallenge...
The technical chaps at Owen Developments have always been very helpful with turbo sizing questions when I've called them in the past. They have yet to sell me a wrong un (or 2).
I think to get 500BHP out of an engine that large should only need a couple of quite small turbos so lag should be well under control.
Garrett do an Iphone app which allows you to put in all your parameters and then it makes recommendations on the right turbo (but only their turbos). I think it's called Turbo Boost Advisor. Still worth having a chat with them though as experience is worth more than a computer program when spending that kind of money.
I think to get 500BHP out of an engine that large should only need a couple of quite small turbos so lag should be well under control.
Garrett do an Iphone app which allows you to put in all your parameters and then it makes recommendations on the right turbo (but only their turbos). I think it's called Turbo Boost Advisor. Still worth having a chat with them though as experience is worth more than a computer program when spending that kind of money.
Gents thank you for all the input, im keen to get many points of view on this install.
Im not defensive or dismissive on any suggestion, if i knew all the answers i wouldn't have had to ask on here. I'm please Ive had responses, and yes ill keep you updated on progress.
Once again thanks for the input.
Mark
Im not defensive or dismissive on any suggestion, if i knew all the answers i wouldn't have had to ask on here. I'm please Ive had responses, and yes ill keep you updated on progress.
Once again thanks for the input.
Mark
I did a vgt build using a Holset he531 vgt blower with two actuators , one for boost and one vac fed to pull the vane wide open under cruise . Made 480whp with a 2.3 4pot engine and spooled up nicely .
22cm or 2.0 ar with the vane fully open and an 85 lb compressor . T4 flange with 3.5 " turbine outlet .
Turbo was £150 in perfect order and they are easily found in the us as the electric motor gives up and they don't sell the motor separate .
Standard fitment on dodge rams with the 6bt cummins engine .
Had no det issues at high boost mainly down to the low back pressure but eventually broke a piston getting carried away on a Dyno .
Twins would be easier to package and something volvo td05 would be cheap enough as they have a built in re circ to suit a maf based system which I think the v12 uses .
Haven't seen one in a while but don't they run a separate ecu for each bank ?
22cm or 2.0 ar with the vane fully open and an 85 lb compressor . T4 flange with 3.5 " turbine outlet .
Turbo was £150 in perfect order and they are easily found in the us as the electric motor gives up and they don't sell the motor separate .
Standard fitment on dodge rams with the 6bt cummins engine .
Had no det issues at high boost mainly down to the low back pressure but eventually broke a piston getting carried away on a Dyno .
Twins would be easier to package and something volvo td05 would be cheap enough as they have a built in re circ to suit a maf based system which I think the v12 uses .
Haven't seen one in a while but don't they run a separate ecu for each bank ?
dblack1 said:
To explain why I recommended a twinscrew over a turbo:
1. Regardless of your turbo setup there will be some lag, he indicated he wanted power on demand, while lag will be short on a well designed turbo setup, the twinscrew setup will deliver the power on demand.
2. Twinscrew setups are more efficient than roots setups at higher RPMs, but provide the advantages to a positive displacement blower.
3. Most setups are less prone to boost leaks, exhaust heat related problems (cracking mostly), significant amounts of oil leaking from the blower into the intake.
4. Most ultra high performance twinscrew setups are more street friendly than a turbo setup producing the same power.
1. true, but on a well designed setup, not an issue. But yes, the instant response from a blower is great1. Regardless of your turbo setup there will be some lag, he indicated he wanted power on demand, while lag will be short on a well designed turbo setup, the twinscrew setup will deliver the power on demand.
2. Twinscrew setups are more efficient than roots setups at higher RPMs, but provide the advantages to a positive displacement blower.
3. Most setups are less prone to boost leaks, exhaust heat related problems (cracking mostly), significant amounts of oil leaking from the blower into the intake.
4. Most ultra high performance twinscrew setups are more street friendly than a turbo setup producing the same power.
2. Than a Rootes yes, but that wouldnt be difficult as they are fairly poor overall
3. Boost leaks are always shoddy workmanship, and Ive never had a functioning turbo install in 20 years leak oil into the intake.
Potential exhaust cracking...yes it can be, but again some thought and workmanship can prevent that.
A blower install is complicated as far as brackets goes, you have belt system reliability, and then lack of intercooling on almost all setups. But that would of course depend on boost used. Also, proper twin screw blowers are pretty expensive to buy are they not ?
4. Street friendly is very debatable. Huge torque on tap in an instant with a 5.0 V12 in a 1000kg car ? Unless it is 4wd or runs huge slicks on a sticky track, I can see issue there.
Now if it was a 2-3 ton car, all that torque would be fantastic on the street.
Plus with any blower, options for variable boost are very limited. With a turbo install, you really have many options.
All boils down to what the user wants or expects, and the application. Either a twin screw or turbo can be fantastic when used correctly. Each has their good points and bad. But regardless, I'd still say a turbo setup is always cheapest and easiest to do on a budget, and will offer the most flexible outcome in terms of power delivery and options.
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