Discussion
Hello all.
How do you size up a turbo for an application?
Lets say I wanted 900hp from a 5.6 litre V8, not revving it past 6500rpm and on 95 Octane fuel. That's only 161hp per litre and it will be chargecooled, so lets also assume that I can keep the temps down reasonably well.
I want it to spool up quite quickly aswell as it'll be used for drag racing.
Do you just go for a turbo that can handle 500hp easily and then buy 2 of them?
Do you run a set that has proven 900hp on Other engines, Skylines, Supras etc?
Do I need to know the boost I expect i'll need to make 900hp and then build the compression ratio to suit, or name a compression ratio and then map it to handle the boost it needs?
I want it to be quite responsive but I think there are lots of aspects about this that I need to take into consideration before I go ahead.
Dave!
How do you size up a turbo for an application?
Lets say I wanted 900hp from a 5.6 litre V8, not revving it past 6500rpm and on 95 Octane fuel. That's only 161hp per litre and it will be chargecooled, so lets also assume that I can keep the temps down reasonably well.
I want it to spool up quite quickly aswell as it'll be used for drag racing.
Do you just go for a turbo that can handle 500hp easily and then buy 2 of them?
Do you run a set that has proven 900hp on Other engines, Skylines, Supras etc?
Do I need to know the boost I expect i'll need to make 900hp and then build the compression ratio to suit, or name a compression ratio and then map it to handle the boost it needs?
I want it to be quite responsive but I think there are lots of aspects about this that I need to take into consideration before I go ahead.
Dave!
Best thing is to ask from those who have done it before you. A lot depends on the engines ability to breathe too.
I dont see why, if its a decent 5.6litre engine in the first place, something like a pair of T60's or GT30's or thereabouts should do fine.
Exhaust housing, and manifold design will play as big a part in spool, as the compressor itself. Even a huge compressor wont be laggy, if you have a small turbine housing...but then that turbine housing might become a restriction at some point.
A CR of around 8.5:1 should be pretty safe ( assuming good intercooling ) to achieve your goals on crappy fuel.
I dont see why, if its a decent 5.6litre engine in the first place, something like a pair of T60's or GT30's or thereabouts should do fine.
Exhaust housing, and manifold design will play as big a part in spool, as the compressor itself. Even a huge compressor wont be laggy, if you have a small turbine housing...but then that turbine housing might become a restriction at some point.
A CR of around 8.5:1 should be pretty safe ( assuming good intercooling ) to achieve your goals on crappy fuel.
Your sorta asking the same questions i did when trying to select a turbo (but on a greater scale). Suppliers always asked "how much power do you want to make" - i would say "whatever i can get away with on 9.25 cr" - which isn't an answer.
Luckily - you have your power goal in mind already, so just either by one turbo that supports that level or pair that supports half that level.
Talk to the american turbo suppliers, as they have relevant experience and give good advise. Get yourself over to turbomustangs and do lots of reading and searching.
www.turbomustangs.com/smf/
As for CR, there is a calculator somewhere that will show your effective CR at a particular boost level - but dropping the CR into the low-mid 8's should get you there.
Luckily - you have your power goal in mind already, so just either by one turbo that supports that level or pair that supports half that level.
Talk to the american turbo suppliers, as they have relevant experience and give good advise. Get yourself over to turbomustangs and do lots of reading and searching.
www.turbomustangs.com/smf/
As for CR, there is a calculator somewhere that will show your effective CR at a particular boost level - but dropping the CR into the low-mid 8's should get you there.
what engine is it your looking at?? i know its only a trivial thing but it helps with what works for diffrent applications.
also you cant just say "i want this power so i need this turbo"! if you want that much power from a LSx engine then people will say go for a T88 (capable of well over 1000bhp). but alot forget that a hybrid T76 can flow over 1000bhp and give you better spool!
also what car are you putting it in??? this can help decide if its easier to go twins or a big single!
will it only be used at the drag track? if so you can live with a bigger but slower spooling turbo for one that makes more power. and if it lags to muhc you can just use some N2O to spool it off the line. if its as a road car then you need to look at ways to combat the lag that are more road freindly.
so, what engine in what car for what use????
thanks Chris.
also you cant just say "i want this power so i need this turbo"! if you want that much power from a LSx engine then people will say go for a T88 (capable of well over 1000bhp). but alot forget that a hybrid T76 can flow over 1000bhp and give you better spool!
also what car are you putting it in??? this can help decide if its easier to go twins or a big single!
will it only be used at the drag track? if so you can live with a bigger but slower spooling turbo for one that makes more power. and if it lags to muhc you can just use some N2O to spool it off the line. if its as a road car then you need to look at ways to combat the lag that are more road freindly.
so, what engine in what car for what use????
thanks Chris.
It is a 5.6 litre M117 bottom end from the 560 SEL and i'll be fitting some M119 twin cam heads to it. I know the bore spacing is the same and people have seen these heads on this block. The block is about as strong as they come so will use this instead of trying to find a closed deck M119 engine.
Pistons and Rods need to be made but this is easy enough, only money, eek.
It'll be going in a MK1 Escort, the chassis is spaceframed and 4 linked ready for the engine but I need to know what i'm looking at pricewise for the engine before I go ahead with it, a wide spread of power will be good as i'm using a 2 speed powerglide, I don't care if it takes me a long while to source the bits.
I'd prefer to go twin turbo due to space issues and it will also be road legal so i'll mainly use it on the road for.
I don't think 160hp/litre is too much to ask from it?
Dave!
Pistons and Rods need to be made but this is easy enough, only money, eek.
It'll be going in a MK1 Escort, the chassis is spaceframed and 4 linked ready for the engine but I need to know what i'm looking at pricewise for the engine before I go ahead with it, a wide spread of power will be good as i'm using a 2 speed powerglide, I don't care if it takes me a long while to source the bits.
I'd prefer to go twin turbo due to space issues and it will also be road legal so i'll mainly use it on the road for.
I don't think 160hp/litre is too much to ask from it?
Dave!
sounds like a very nice piece of kit!! please keep us updated on how its going! do you have any links or pics of the car now???
well as posted above a set of GT30Rs will give you the power to need but are more costly than the turbonetics stuff but should spool faster as they are true dual ball bearings.
also worth looking into is the intercooling. if you are manly going to be using this thing at the track then have you thought about a water to air chargercooler instead of the intercooler??? it will give you colder intake temps (when you use ice/water) and if you only running a little bit of boost on the road then a splash of meth should cool the intake enough. also with the chargcooler/s you can mount them in a esier location. alot of the US guys stick them behind the dash.
also might want to have a look on LS1tech.com to see how thoes guy with the engines do the twin turbo thing.
thanks Chris.
well as posted above a set of GT30Rs will give you the power to need but are more costly than the turbonetics stuff but should spool faster as they are true dual ball bearings.
also worth looking into is the intercooling. if you are manly going to be using this thing at the track then have you thought about a water to air chargercooler instead of the intercooler??? it will give you colder intake temps (when you use ice/water) and if you only running a little bit of boost on the road then a splash of meth should cool the intake enough. also with the chargcooler/s you can mount them in a esier location. alot of the US guys stick them behind the dash.
also might want to have a look on LS1tech.com to see how thoes guy with the engines do the twin turbo thing.
thanks Chris.
Total unconditional respect! I want to have a go!I've had the car for 3 years getting bits slowly done to it, it wont be done next week haha.
www.chargecooler.co.uk/
I'll be using these for the Chargecoolers, people rate them and they will be far easier to fit than an Intercooler due to my space problems.
Dave!
www.chargecooler.co.uk/
I'll be using these for the Chargecoolers, people rate them and they will be far easier to fit than an Intercooler due to my space problems.
Dave!
Howitzer said:
I've had the car for 3 years getting bits slowly done to it, it wont be done next week haha.
www.chargecooler.co.uk/
I'll be using these for the Chargecoolers, people rate them and they will be far easier to fit than an Intercooler due to my space problems.
Dave!
www.chargecooler.co.uk/
I'll be using these for the Chargecoolers, people rate them and they will be far easier to fit than an Intercooler due to my space problems.
Dave!
Ive just completed another complete page on chargecooler testing, pumps and water reservoir. See www.mez.co.uk/turbo13.html
Howitzer said:
I've had the car for 3 years getting bits slowly done to it, it wont be done next week haha.
www.chargecooler.co.uk/
I'll be using these for the Chargecoolers, people rate them and they will be far easier to fit than an Intercooler due to my space problems.
Dave!
www.chargecooler.co.uk/
I'll be using these for the Chargecoolers, people rate them and they will be far easier to fit than an Intercooler due to my space problems.
Dave!
they look very similar to the PWR cooler that are sold in oz (i think). they look very nice pieces of kit! its going to be interesting how you mount them though. where are you thinking of putting the turbos??? most US guys mount them forward and then have a box style chargecooler.
thanks Chris.
chuntington101 said:
Howitzer said:
I've had the car for 3 years getting bits slowly done to it, it wont be done next week haha.
www.chargecooler.co.uk/
I'll be using these for the Chargecoolers, people rate them and they will be far easier to fit than an Intercooler due to my space problems.
Dave!
www.chargecooler.co.uk/
I'll be using these for the Chargecoolers, people rate them and they will be far easier to fit than an Intercooler due to my space problems.
Dave!
they look very similar to the PWR cooler that are sold in oz (i think). they look very nice pieces of kit! its going to be interesting how you mount them though. where are you thinking of putting the turbos??? most US guys mount them forward and then have a box style chargecooler.
thanks Chris.
They are PWL chargecoolers, there was a thread on here a while a go, we were trying to determine the efficiency of them - the guy couldn't provide actual efficiency figures (and declined to allow me to test one)
i know of an Evo 3 that was running one and he said they are great! you just need to make sure the pre rad is MASSIVE! people seem to forget you dstill have to get rid of the heat out of the water. lol
steve, what size water tank was he running??? heard of loads of V8 guysing running about 1.5 gallon was and running ice in them. one guy was running well into the 9's with about 7-800 (american) rwhp. he said after the run the water was "bath tub" warm, so i guess it does get pretty hot towards the end of the run!
has the Scooby guy thought of running both an intercooler and a chargecooler steve??? then he can get air temps down closer to ambient with the intercooler and then let the charecoller get them well below ambiant (with ice).
thansk Chris.
steve, what size water tank was he running??? heard of loads of V8 guysing running about 1.5 gallon was and running ice in them. one guy was running well into the 9's with about 7-800 (american) rwhp. he said after the run the water was "bath tub" warm, so i guess it does get pretty hot towards the end of the run!
has the Scooby guy thought of running both an intercooler and a chargecooler steve??? then he can get air temps down closer to ambient with the intercooler and then let the charecoller get them well below ambiant (with ice).
thansk Chris.
Howitzer said:
Hello all.
How do you size up a turbo for an application?
Lets say I wanted 900hp from a 5.6 litre V8, not revving it past 6500rpm and on 95 Octane fuel. That's only 161hp per litre and it will be chargecooled, so lets also assume that I can keep the temps down reasonably well.
I want it to spool up quite quickly aswell as it'll be used for drag racing.
Do you just go for a turbo that can handle 500hp easily and then buy 2 of them?
Do you run a set that has proven 900hp on Other engines, Skylines, Supras etc?
Do I need to know the boost I expect i'll need to make 900hp and then build the compression ratio to suit, or name a compression ratio and then map it to handle the boost it needs?
I want it to be quite responsive but I think there are lots of aspects about this that I need to take into consideration before I go ahead.
Dave!
How do you size up a turbo for an application?
Lets say I wanted 900hp from a 5.6 litre V8, not revving it past 6500rpm and on 95 Octane fuel. That's only 161hp per litre and it will be chargecooled, so lets also assume that I can keep the temps down reasonably well.
I want it to spool up quite quickly aswell as it'll be used for drag racing.
Do you just go for a turbo that can handle 500hp easily and then buy 2 of them?
Do you run a set that has proven 900hp on Other engines, Skylines, Supras etc?
Do I need to know the boost I expect i'll need to make 900hp and then build the compression ratio to suit, or name a compression ratio and then map it to handle the boost it needs?
I want it to be quite responsive but I think there are lots of aspects about this that I need to take into consideration before I go ahead.
Dave!
have a look at this thread. looks like there is a new 88mm garret unit out that could give you your needs. might be a bit big thouhg! lol
www.ls1tech.com/forums/showthread.php?t=616407
its towards the bottom,. Dr turbo talks about the new 88mm Garret with Dual Ball bearingS!
thanks Chris.
chuntington101 said:
i know of an Evo 3 that was running one and he said they are great! you just need to make sure the pre rad is MASSIVE! people seem to forget you dstill have to get rid of the heat out of the water. lol
steve, what size water tank was he running??? heard of loads of V8 guysing running about 1.5 gallon was and running ice in them. one guy was running well into the 9's with about 7-800 (american) rwhp. he said after the run the water was "bath tub" warm, so i guess it does get pretty hot towards the end of the run!
has the Scooby guy thought of running both an intercooler and a chargecooler steve??? then he can get air temps down closer to ambient with the intercooler and then let the charecoller get them well below ambiant (with ice).
thansk Chris.
steve, what size water tank was he running??? heard of loads of V8 guysing running about 1.5 gallon was and running ice in them. one guy was running well into the 9's with about 7-800 (american) rwhp. he said after the run the water was "bath tub" warm, so i guess it does get pretty hot towards the end of the run!
has the Scooby guy thought of running both an intercooler and a chargecooler steve??? then he can get air temps down closer to ambient with the intercooler and then let the charecoller get them well below ambiant (with ice).
thansk Chris.
I have just completed testing on my low boost setup and found 2 gallons works well, I did try 4 gallons but not enough benefit (for me)
More boost=more heat=probably more water.
Full write up: www.mez.co.uk/turbo13.html
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