If the exhaust housing is 58020 then it is from a cruiser. The Supra housing is just massive by comparison.
Personally, I think the Supra housing is too big for our application as does the only person I've heard of who has tried it. Well, too big to be
drivable. He reported no boost until 2000rpm which is bloody useless for a vehicle like this under normal, real world driving conditions. I'd love to be able to build boost even earlier than I already do without having to add any more excess fuel. Going to the larger housing will ultimately allow more air to flow out but I'm far more concerned with what's happening at 1500-2000rpm than 4000rpm.
As far as the details, the only difference between the compressor wheels is that the 7M-GTE has a 47mm inducer vs the 43mm inducer used on the 1HD-T and 3S-GTE. The exducers are the same, and the turbine sides are the same.
Performance wise, I noticed no down side to the swap. My boost comes on just the same as before but it can hold the boost to higher rpms. With the 1HD-T compressor and a semi-dirty tune I could boost something like this (assume truck loaded, at least 2nd gear, and stomping hard):
1500rpm - 10psi
1800rpm - 14psi
2000rpm - 16psi (max set by boost controller)
3000rpm - 12psi
3500rpm - 10psi
As you can see, it just couldn't get enough air to keep that boost up. The problem wasn't the inability to make boost, it was the inability to make boost at high CFM.
Switching to the 7M-GTE compressor allowed me to hold that 16psi all the way to 3500rpm. I never go higher so I can't comment beyond that. I've since been running it with the MBC maxed at 18psi for about 3000km and it will still hold that right up to 3500rpm.
If you have time on your hands and want to listen to the real experts talk, there's lots of good info in
this thread around page 10-11 (well, the whole thing is good).
Also,
this thread
