The drivers side of the engine is a mess of hoses and wiring without the factory intake manifold covering it up. We opted for the Stillen engine cover that fits over the drivers side and weaves in nicely with their intake manifold. Additionally we opted for the 9lb boost pulley. The current 8lb pulley supplied with the kit is good for 9-10 psi. The 9lb pulley should produce somewhere around 11-12psi of boost.
Soho then supplies their own
- Intercooler
- Block off plate to convert Stillen manifold over to Air to Air from Air to Water
- Breather filter
- 4 large hose clamps
- 6 medium hose clamps
- 4 intercooler hoses
- K&N filter
- Tial Blow Off Valve
- 2 intercooler pipes
- Crash bar and tow hook (optional)
- Injector adapters for easy installation of our ID1050x fuel injectors (optional)
- Eight gauge SPAL fan harness to power our fuel pump (optional)
Dealing with Soho during this process was a big relief for the many, many questions we had along the way. This sort of upgrade with all these parts from many different manufacturers resulted in many questions. George at Soho answered all of our questions in his extremely polite demeanor and he never rushed us off a call. They have a full service shop in North Carolina complete with installation and dyno tuning. If you’re looking to add major or minor upgrades to your Nissan 370z or Infiniti G or Q, Soho is a great place to start.
14 comments
Wait, 60-70whp from a filter? Do you mean 6-7?
Yes 60-70whp in forced induction doesn’t seem out of the realm of reality. We haven’t confirmed this with our own car this was confirmed by both Soho and our tuner at Specialty Z.
Here are a couple of dyno charts for your reference if you scroll down a bit on these pages. While they don’t show the results with the filter on and off they are really big numbers for a supercharged v6. Based on the numbers we’ve seen on our car and others I’d think these runs were with the turbo guard.
https://sohomotorsports.com/products/soho-motorsports-a2a-supercharger-kit
https://sohomotorsports.com/products/soho-motorsports-air-to-air-upgrade-for-the-stillen-vq37vhr-supercharger-kit
In this particular case with a supercharger, 60-70whp seems reasonable. Once you see the install, you’ll see how little space is available for the filter and why the small K&N from the H-D was used. Relatively speaking, this filter is highly restrictive. On a turbo car, you can adjust the wastegate to spin the turbo faster. On a supercharger, it only spins as fast as the fixed pulley sizing will allow, so it can’t compensate for loss of mass air flow due to the restrictive air filter. So, 60-70whp loss is the result.
Because of space constraints, this is a silly small filter. In the future, we might cut a hole in the core support and fabricated something less restrictive to test.
why the move to air to air? whats wrong with air to water?
If you have the space, air to air is generally better, air to water systems have smaller bricks and greater pressure drop and the water side has smaller heat exchangers and can thermally saturate more easily.
is it possible to make an air to water system that won’t saturate? that would fit in a car that is, not some enormous system in a lab with no space constraints… or will all air to water systems saturate? specifically in a lapping day scenario with 20-30 min sessions…
It can be done. Just have to size a really big radiator for the IC system. Ferrari ran an air-to-water setup on their F1 car. so yeah, it can be done.
I think You would be better off using some sort of cobra-head silicone hose and re-routing the filter somewhere more sensible.
https://www.do88.se/en/artiklar/silicone-hose-_-hoses/silicone-hose-black/cobra-head/index.html
I’ve never seen a silicone hose like that before. I took a look at the flow charts and it seems like the testing is there to prove the airflow improvements over a 90 degree hose. At some point we’ve got to punch through the core support and get past the radiator to the fresh air in front. I’d think we’d also want a shield to prevent turbulence in airflow; similarly to what was on our V3 cold air intakes from Stillen when the car was N/A.
This is definitely top of mind before we start looking at e85 or adding more boost.
Do you have a part number for that KN Filter?
I’ll get in touch with the vendor and get the part number.
The part number is a K&N # RX-4130-1
What would you think the hp gains would be like with running soho’s air upgrade that they use on their new a2a kits? it routes it to the front around the bov with a full filter like you described. I will also be running a 9lb pulley with long tube headers hoping to make 600whp on 93