Okay, so I'm still devoloping my 20b build. I want a streetable responsive ride at around 450-500whp and am willing to drop some top end power for that. So, I've been trying to see how I could get those numbers with a sequential setup, but the stock manifold is very restrictive for exhaust gases even with a ported opening, the doors are still a problem. Although, if someone has a sequential set-up with those numbers let me know. Anyways, I got looking into supercharging. Decided if I go supercharged I'm going twin-screw setup. Only two problems though, one is fitment under the hood and the other is matching size while clearing the 30psi mark, hopefully clearing 20psi.

So if anyone has gone or looked into going supercharged 20b, let me know your opinion on the best size of twin screw supercharger to go with. I'd like to havesome more knowledge before calling them up, since matching cfm charts with displacement is beyond my knowledge.

Thanks.

 

I am confused. Did you want 450-500whp or 20-30psi boost? Also, what kind of engine porting?

 

Ah hey Evil.. Oh yeah forgot to say porting. Just mild street, porbably could make it bigger but bottomline is nonperipheral. And what I mean by clearing the 30 psi mark is it seems that is the max boost the whipple supercharger pushes before choking is 30 psi (so far from my understanding). So nothing too big that will push too much psi or lose efficiency by increasing the pully ratio. But also nothing that is going to exceed max rpm at 8k if such exists. Oh incase anyone wonder why the low power goal.. I'm not sure what model my 20b is, so I'd like to stay on the safe side.

If still confused, let me know. I'm stil learning so I might have gotten something backwards. Thanks again.

 

Yes, still confused, lol.

At 20-30psi you are looking at around 600-900whp on a 20B. This is definitely not "on the safe side" with an otherwise unmodified engine, lol. It will also require a serious amount of modifications.

If you just want something with good street response, you could simply copy this excellent turbo setup in the below link for much less money and effort than a massive supercharger project. It fits square in the middle of your original 450-500whp goal with a very mild 11psi boost level, and I am sure the response is excellent. The tuner often makes road trips for tuning events.
http://www.7parts.com/erikstrelnieks.html
http://www.7parts.com/forums/viewtopic.php?t=12

 

And here's where I shamelessly plug my setup! LogicFoxX, check out the FS ad linked in my sig for the 20B manifold. Plenty responsive, and you could easily achieve your goals with just a different WG spring. BAM!

 

Hey, I like that dynograph, pretty solid. I def might go with that instead. Beats the t-64 and t-72 graphs as far a linearity. But outta curiosity, what size would you go with to meet the 500hp mark on an otherwise unmodded engine? 1600 or 2300?

 

Well guess it's one of those things, "If you have to ask." But thanks for the help anyways, maybe upgrade to supercharged at a later date when I get bored with a turbo setup.

 

ide be looking at the w175ax or bigger. certainly the more exspensive way to get such little hp.
But then I want the W305 to replace my Weiand unit if I ever have the coin to do it

 

Hmm cool, Noted, thanks for that tid-bit.

Although, I've long ago decided to not invest my money and instead poor it into my money-disposal of a car.

 

oh, so your a member of my club lol