Sorry I just checked and couldn't find it. Keep an eye out on ebay for a used one or even craigslist. They are very good manifolds for boost.

 

If you want more power, I would recommend simply upgrading your map sensor & upping the boost.

I have tuned several stock b18 & b20 motors to the 280-300 whp range.
They all are still on the road today without any problems.

I have personally tuned on a dynocom dyno (over 50 cars).
They work great, however the dyno can be misleading if the dyno is not setup properly.

I would suggest you throw your car on a dynojet for a comparison.

 

I tuned a b20b that only put out 243 at 8.5psi on a dynojet. Top end was a bit on rich side so I am assuming it would put down 250ish when we go back to finish tuning.

Setup was...
b20b 9.2:1 CR
P8R head
Victor X manifold
70mm Throttle Body
Ram Horn Manifold
2.5" Down Pipe

That is why I said your setup seems very strong.

Hey John, back to being friendly...what turbo and psi do you recommend for 280whp on a b20b?

 

how much hp do you think a completely stock b20 can handle? if i can pull a little more power out of it safely then ill go back an turn up the boost a little. i didnt want to push it to far thats why i stopped where i am at right now. ive read everywhere about the cylinder walls being thin due to the bore.

 

They are thin but it's all in how well the motor is tuned. If you get the new intake manifold and throttle body combo and maybe slap in some crower 62402-2's you will make more power without having to increase boost pressure. I bet with those mods you will see a good 10-15whp jump.

If you want to be ready for the future, if your staying nonvtec, get some 404's with springs and retainers...they will even up your power right now.

 

Apples to oranges. If you want to compare your numbers to a DynoJet throw it on a DynoJet for three pulls or run it down the track