The turbo is an air pump, if it is pumping more air than the engine can use then the compressor can go into surge (worst case) or add more heat into the charge air than it should (low efficiency).
Lotus Elise K24 turbo build
I thought I would create a thread to take advantage of the collective experience on K20a.org. I have a similar build thread on LotusTalk.
My build will utilize a JDM K24a RBB-3, an EFR 7163 turbo, RBC intake manifold, Skunk2 70mm TB, and custom exhaust manifold. Intake cooling will be air to water. The Haltech 1500 Elite will be used for engine management as well as controlling electric pumps for the engine and charge A/W cooler. The plan is for a flex fuel set-up with ID 1300xds injectors and all the appropriate sensors and safety controls including individual EGTs. I could go into a lot more detail if anyone is interested but you get the gist.
My goals are a street/track car with great drivability. We are keeping the K24 stock other than upgraded oil pump (at least for now
) so boost will be limited in the low RPMs to avoid bending rods and such. The Haltech 1500 has multiple boost control strategies and the EFR comes equipped with an integrated boost control solenoid, wastegate and recirculation. We should have a lot of options. It is also a pretty compact set-up which makes things a lot easier for an Elise build.The HP will be whatever can be achieved with comfortable margin of safety given a K24 with stock internals. My builder has extensive experience tuning K-series so no issue there. My plan is to leave it to him but I must say I am more than a bit excited after seeing the results of other K24 builds with low boost and stock internals.
My Elise's had a REV400 SC 2ZZ and we will be carrying over the Toyota e153 tranny. It might seem an odd decision but it turns out there are e153 to K series conversion kits readily available for MR2 swaps. My e153 has a close ratio KAZ gear set with a LSD and 3.9 FD. It is pretty much new with beefy axles so why the heck not. I haven't really come across any Lotus K series turbo e153 builds so maybe it's something unique.
My build will utilize a JDM K24a RBB-3, an EFR 7163 turbo, RBC intake manifold, Skunk2 70mm TB, and custom exhaust manifold. Intake cooling will be air to water. The Haltech 1500 Elite will be used for engine management as well as controlling electric pumps for the engine and charge A/W cooler. The plan is for a flex fuel set-up with ID 1300xds injectors and all the appropriate sensors and safety controls including individual EGTs. I could go into a lot more detail if anyone is interested but you get the gist.
My goals are a street/track car with great drivability. We are keeping the K24 stock other than upgraded oil pump (at least for now
) so boost will be limited in the low RPMs to avoid bending rods and such. The Haltech 1500 has multiple boost control strategies and the EFR comes equipped with an integrated boost control solenoid, wastegate and recirculation. We should have a lot of options. It is also a pretty compact set-up which makes things a lot easier for an Elise build.The HP will be whatever can be achieved with comfortable margin of safety given a K24 with stock internals. My builder has extensive experience tuning K-series so no issue there. My plan is to leave it to him but I must say I am more than a bit excited after seeing the results of other K24 builds with low boost and stock internals.My Elise's had a REV400 SC 2ZZ and we will be carrying over the Toyota e153 tranny. It might seem an odd decision but it turns out there are e153 to K series conversion kits readily available for MR2 swaps. My e153 has a close ratio KAZ gear set with a LSD and 3.9 FD. It is pretty much new with beefy axles so why the heck not. I haven't really come across any Lotus K series turbo e153 builds so maybe it's something unique.
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Gotcha, that's something I've just learned. Not only can a turbo choke by trying to produce too much boost going past the efficient zone (blue), but it can also choke or surge by being under or above that efficiency island (red/yellow). Though, yellow line would be something like a super small turbo fitted to a large engine, and red would be vice versa. Hopefully I've interpreted that correctly. Thank you for the information guys.
a small TC would have that efficiency area mostly compressed to the left side of the diagram given the same x-axis scale. The rpm lines would drop off at much lower flow rates. The slope, so PR over flow is steeper for a smaller compressor vs a bigger one.
most of the time, these efficency maps are scaled to show that entire “clam shell”. That scaling adaptation makes them look almost identical.
Here is something to read. Complicated topic as the exhaust turbine also needs to fit the bill.
motoiq.com
most of the time, these efficency maps are scaled to show that entire “clam shell”. That scaling adaptation makes them look almost identical.
Here is something to read. Complicated topic as the exhaust turbine also needs to fit the bill.
Turbo Tech: Compressor and Turbine Map Details - MotoIQ
Turbo Tech: Compressor and Turbine Map Details By Khiem Dinh Khiem Dinh is an engineer for Honeywell Turbo Technologies at the time of this writing. All statements and…
motoiq.com
Its a popular "tuner / Aftermarket" myth that drives sales of blow off valves. If it was a particular issue we would see blow off valves on endurance race cars but instead we tend to get lots of chatter.
Good luck with the build
Race/rally cars also often run anti lag systems bypassing excess air into the exhaust header before the turbine and often afford to swap their turbos
Seems like 1300cc injectors will be too small to run E-85 to it's potential. Why not run something bigger that would allow for room to grow so you don't have to replace them when you want more power?I thought I would create a thread to take advantage of the collective experience on K20a.org. I have a similar build thread on LotusTalk.
My build will utilize a JDM K24a RBB-3, an EFR 7163 turbo, RBC intake manifold, Skunk2 70mm TB, and custom exhaust manifold. Intake cooling will be air to water. The Haltech 1500 Elite will be used for engine management as well as controlling electric pumps for the engine and charge A/W cooler. The plan is for a flex fuel set-up with ID 1300xds injectors and all the appropriate sensors and safety controls including individual EGTs. I could go into a lot more detail if anyone is interested but you get the gist.
My goals are a street/track car with great drivability. We are keeping the K24 stock other than upgraded oil pump (at least for now
My Elise's had a REV400 SC 2ZZ and we will be carrying over the Toyota e153 tranny. It might seem an odd decision but it turns out there are e153 to K series conversion kits readily available for MR2 swaps. My e153 has a close ratio KAZ gear set with a LSD and 3.9 FD. It is pretty much new with beefy axles so why the heck not. I haven't really come across any Lotus K series turbo e153 builds so maybe it's something unique.
Yeap, a nice ECU, released today here in Europe 😄, but a bit disappointing as for DI, free function programming and some other CAN stuff you still need BOSCH, MoTec, Syvecs, ...that was the chance to go into a bigger market and balance the ECU prices new. They missed it.
A BOSCH MS 6, even in the version 6.1, a more powerful on the functional side if inputs (around 20 analog, more on the higher version) are enough. Torque based control, 3 CAN, Matlab/Simulink interface for customizing all what you can think of, ...like a BOSCH
. I like the NSP SW, which is really a step forward but there is a reason why 100's of SW engineers working on "safe" over air methods like BEV's are using it. That Wireless stuff is nice, but comes with a lot of questions for me. BTW, (over air) map switching
, the over 10 year old AEM Infinity was also able to switch maps, blend maps, that is just SW with an analog poti port connected. Did you look at others like MaxxECU Pro or ECUMaster Emu-Pro 8, those have a very attractive price-value-ratio. Both are CAN capable, have enough out- and inputs, and an easy-going SW with a lot of supporting features.
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