What pulley combo/boost for 1100whp Magnuson 2650
 

I'm adding the toohighpsi port with a fore triple system. My car currently has a Magnuson 2650 with a 103mm tb/snout and 5" cordes intake.

What pulley combo would yield 20psi or at least 1100whp? I was considering a 75mm upper and 9.45(17%) lower.

You might want to look into larger tb/snout alternatives, too.

I'd say your gonna make good boost with that combo. Probably around 18 to 20 psi. You can also give Mike Sitar a call at THPSI. His Z06 had a 2650 to develop the port injection. He can probably give you a better idea on the 9.45 with the 75 mm. I ran the 75 with a stock lower on my 16ss with the 2650 and we made about 15 to 16 psi and around 850 at the wheels, so with the bigger lower your gonna make plenty of power. Should be in the 1000 wheel I would think with your new setup.

The pulley combo referenced can get you there on someone's dyno using ethanol, assuming good flowing heads, but I also think your TB and inlet will limit you. I'd look at getting a 112mm for both.

Agreed. Shooting for 1100 WHP is going to be asking for a lot out of a 103 TB.

At what level is the typical 5” Big Gulp a restriction in your opinion?

It is hard to say as we have never tested it. I left the Big Gulp at a little over 1k RWHP, but only because I wanted to easily be able to remove the filter and use a bell mouth. The bell mouth is worth a solid 40 RWHP at 1200 RWHP, just at the risk of sucking stuff into your blower. My current custom intake is only 5" though. They are testing larger ones that are showing some gains, so we'll see where it lands.

My buddy going for 1200hp with his maggie Z06 had to get that 120mm TB and new snout.

Good info. I’ll shoot for what I can on the 103mm. If I don’t make it I’ll consider just using a bell mouth for race nights and dyno runs.

Yeah I’ve got the bell mouth as well but it really raises havoc with the MAF scale. I went to run it one day at the track and decided against it….the blower belt broke the next run and filled the air filter with debris from the hood liner, belt shreds, etc…! That would have all been in my motor if I had run the bell mouth… :smm7:

Maybe Vengeance can develop a 5.5-6.0” intake (perhaps using metric sizes) with integrated bell mouth that is still covered by a gigantic filter. I guess the market demand isn’t huge…just a few of us crazies lol…

It is definitely a risk to run with no filter. I've had some belts explode while using it as well. The MAF used to freak out on mine, to the point where I had a separate tune for it. The current engine runs much better with it and I can use the same tune.

From what I'm told, they might offer this new intake to those that want it, but there won't be any filter. Just a massive 8" bellmouth. It probably needs to be sold with a disclaimer if they do. :smiling1:

That would be cool, please let us know if they do! :happy0180:

You'll probably need a touch more pulley than that unless it's a really happy dyno.

Test it and see where you're at. I think you'll need 23,500+ blower RPM to make 1,100RWHP. This is assuming you have an aftermarket cam, decent heads, and a decent flowing exhaust.

I'll have my 112mm TB & snout combo for sale in August

Really now? With a 90mm/9.06 combo I'm making low/mid 900s @ ~15psi.

I figured 75/9.45 would easily yield enough boost. Perhaps I'll go with the biggest common lower I see without relocating anything, the 9.84.

Then I'll play with upper pullies starting with a 2.85 until I see the magic 11xx. Biggest concern going smaller on the upper is belt slip since I'll be using an 8 rib setup.