Good point :likecat:

Ahhh, here's one.

Theoretically, the C38 and C30 make the same power/tq. Since the C38 isn't working as hard, should it have slightly lower AITs? It's only $100 more to start with it vs the C30, and I know the mounting/charge pipes are all different (I think) if you move to it later on.

Even if I'm not planning on some crazy built motor for years or ever, is there any reason to go with the C38 over C30?

Sounds like a gt28 vs gt2560 efficiency discussion :laugh:

Maybe response differences? I'd contact and ask.

Always down for lower temps and longer longevity of the blower too :likecat:

I wonder what type of intercooler they're using... "High Flow Powder Coated Air-To-Air Intercooler" :dunno:

wouldn't you have to bleed off boost with the 38 to keep it from bending rods?

Belt driven superchargers don't have comparable response to turbos. Different ballgames.

I'm looking now, I was just assuming they use a different pulley to spin it a bit slower but still get the same volume of air?

IN reality, it's not necessary. Like I said, the C30 on E85 and the High Boost Pulley already will make nearly 400whp.


EDIT: Found it. The use the same pulley sizes.

"It's not spinning at the same speed. The gear ratio of the c30-94 is a 9.49 multiplier, while the C38-81 is 7.50. The difference in compressor efficiency is small enough that it falls under the error range of most dynos."

Sound like lower temps and longevity is the way to go then :bigtu: Even if they're marginal differences. Won't the oil inside the rotrex not get as hot spinning at slower speeds?

Well those first two are just speculation on my part.

Possibly, but the Rotrex has it's own air-to-air cooler for the tractive oil in the S/C.

Would be adding 3 heat exchangers, intercooler, Rotrex cooler, engine oil cooler.

Correct. Also, can confirm SC oil too hot = expensive failure.

Pat, do you know of any other sc oils possibly used? Maybe of the amsoil variety ?

dude. centri is not gonna run hot like his twin screw.

let's keep convo relevant

For a rotrex you're stuck with their oil, it's a traction fluid and engineered to work with that drive system. For something like a whipple/eaton, yes there are other oils. I ran JB Performance oil on a recommendation from here, and measured lower oil case temps after changing to their oil vs whipple supplied oil.

If referring to a rotrex which has a traction drive system (I admit I didn't read all this 14 billion post), they run the hottest oil temps, to the point they REQUIRE an oil cooler at any boost level. Roots/twin screws don't require oil coolers until you're in the 25-30 PSI boost range.

Probably. I have no idea. but it doesn't matter.

let's talk moar about z31 boosting his burrz vs what oil to put in it

It needs boost, in fact needs less talk, and moar boost.

:likecat:

Yep, the kit comes with a cooler for the Rotrex.

Looks like it's about $6k all in with the Rotrex kit, CARB tune, and JR engine oil cooler.

Goes from ~160whp to ~285whp...............

really? I didn't think they had the CARB kits doing 285whp
I thought that was the "high boost" setup or the tuner setup with smaller pulley and custom tune.

Do you need a link to click on to buy it?

:D

FR-S/BRZ C38 Supercharger System | Jackson Racing

High boost pulley + E85 = 380whp.

Until the stock rods ventilate the block

:cry:

My tax guy just called. Looks like the pain from the divorce isn't quite over (losing the mortgage deduction and having to move some money around to pay for everything involved in getting a divorce).

My tax bill for this year = about 75% of what everything would cost. I was expecting $1-2k, not $4500.

Edlebrock screwed up going with the TVS900. The 2.0 supercharged cobalt uses the TVS1320 as an upgrade from the M62, and thats about proper sized for most peoples aspirations with a supercharged 2.0.

*Wait a tick Edlebrock did decide to go with the TVS1320, why the fuck arent these making 350hp on e85?