Inlet air temps on a turbo engine vs a blower engine
10-23-2020, 03:48 PM
#11
IMO it won't be as easy as you think finding a water cooled turbo to bolt on to your application, I could be wrong. There might be some trial and error. If it was me, I would put the biggest intercooler you can reasonably fit.
If I'm not mistaken,there is a member on this site with a turboed ls. I think he has it in a platoon boat. Try doing a search.
If I'm not mistaken,there is a member on this site with a turboed ls. I think he has it in a platoon boat. Try doing a search.
10-23-2020, 03:52 PM
#12
Platinum Member
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iTrader: (6)
Gale banks gives all the temps, output efficiency curves for Whipple vs. 10-71
https://www.youtube.com/watch?v=rJ6T...ture=emb_title
https://www.youtube.com/watch?v=rJ6T...ture=emb_title
10-23-2020, 04:41 PM
#13
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Private VIP party in the back...
10-24-2020, 02:12 AM
#14
10-27-2020, 11:22 PM
#15
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Platinum Member
Twin-screw superchargers (Whipple), properly sized, will raise the intake temp around 12 degrees per psi of boost.
TVS-style "improved roots" superchargers (Eaton OEM style), properly sized, around 13 degrees per psi.
Centrifugal blowers (engine-driven or "turbo"), expect around 13.5 degree per psi.
Standard (non-TVS) "Improved Roots" blowers (twisted rotors, Teflon lip seals), you're in the 14+ degrees per psi range.
Traditional old-school roots blowers, anywhere from 16 to 20 degrees per psi.
This is what you're dealing with. And the rule of thumb for keeping detonation at bay is to keep incoming charge temps under 135 degrees. If you can do that, you can consider your setup to be adequately thermally stabilized (at least in the charge-air department).
If it's a 90 degree day, and you run a turbo at 6 psi, you will raise the air temp by 81 degrees to 171 degrees. Your intercooler will need to bring it down under 135 degrees in order for you to expect being able to run effective ignition timing curves. Most OEM turbo/supercharged setups have the ECU's pull timing out starting at 135 degrees IAT. They typically pull boost as well in modern stuff.
Now, all of the above assumes the compressor is properly sized and the plumbing is nor overly restrictive. If you have too many bends, restrictions, or a too-small compressor, it will be required to operate above its thermal efficiency range. This means that the temperature rise goes exponential, making it a losing battle between adding boost vs adding heat.
M
TVS-style "improved roots" superchargers (Eaton OEM style), properly sized, around 13 degrees per psi.
Centrifugal blowers (engine-driven or "turbo"), expect around 13.5 degree per psi.
Standard (non-TVS) "Improved Roots" blowers (twisted rotors, Teflon lip seals), you're in the 14+ degrees per psi range.
Traditional old-school roots blowers, anywhere from 16 to 20 degrees per psi.
This is what you're dealing with. And the rule of thumb for keeping detonation at bay is to keep incoming charge temps under 135 degrees. If you can do that, you can consider your setup to be adequately thermally stabilized (at least in the charge-air department).
If it's a 90 degree day, and you run a turbo at 6 psi, you will raise the air temp by 81 degrees to 171 degrees. Your intercooler will need to bring it down under 135 degrees in order for you to expect being able to run effective ignition timing curves. Most OEM turbo/supercharged setups have the ECU's pull timing out starting at 135 degrees IAT. They typically pull boost as well in modern stuff.
Now, all of the above assumes the compressor is properly sized and the plumbing is nor overly restrictive. If you have too many bends, restrictions, or a too-small compressor, it will be required to operate above its thermal efficiency range. This means that the temperature rise goes exponential, making it a losing battle between adding boost vs adding heat.
M
