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Wondering if this has been tried/discussed in the 951 community? My very limited understanding is that it would not necessarily produce more horsepower (or perhaps less). However, one of the primary challenges of the 951 is throttle response, length of intake runners, and etc - this would seem to be the solution. Another challenge is fitting various 3rd party turbos under the intake, which this could solve too. Lastly, many leaks (loosened connections) are under the manifold, so removing it would have some operational benefits.
Our throttle bodies are already mechanical, so it seems an array of four smaller throttle bodies could be driven from the same cable. As per the video, the fabricating would be some kind of coupler to the cylinders with vacuum ports. Thought would be needed as to how to filter the air on the inlet side and not give up the complete benefit of freeing space up.
The challenge with ITB throttles and turbocharging is that there will be a difference in airflow at different throttle positions but the same boost pressure. This means that the air fuel ratio will change if not accounted for. There are several different strategies that can be employed and will depend on the particular engine. You need get a stable MAP signal using a manifold chamber box to be able to use MAP for any type of correction. I like to use a main fuel table based on TPS and RPM and a secondary table based on MAP and RPM or TPS and MAP to account for the VE differences at different throttle position. I still retain the double pressure double fuel MAP compensation table. I map the engine on the lowest boost setting and get the air fuel ratio correct. Then any changes required are done in the seconday fuel table.
If anyone wants to play I'll sell my hayabusa ITB's for cheap.
I doubt it's worth the effort on a forced induction setup, however on an N/A setup and can lead to lots more hp at high rpm. If you wanted to race an N/A 944 it'd probably be worth it if you have deep pockets.
Engineering Explained has a good video on ITBs, on youtube. It won't necessarily make more power on an NA car either. You will get better throttle response though.
There were some post by Michael Mount of his throttle bodies. Very nice looking pieces. I think some RL'ers bought some of them. Would love to see and hear more about his.
Lindsey Racing also has an ITB thread on here if you search for the past thread.
There were some post by Michael Mount of his throttle bodies. Very nice looking pieces. I think some RL'ers bought some of them. Would love to see and hear more about his.
Lindsey Racing also has an ITB thread on here if you search for the past thread.
Never seen a MM 951 build using itb's, he did a really nice na build a while ago.
He built the throttle bodies only....and posted them on here. They were for the 16V head. He didn't build any 951 engines for anyone using them in a turbo. If you search this forum there are some nice photos of them
Originally Posted by MAGK944
Never seen a MM 951 build using itb's, he did a really nice na build a while ago.
03-21-2017, 10:50 AM
Individual Throttle Bodies / 951
