Originally Posted by GtoRx7

Hey sorry Brandon, I read your message and didnt have time to give a answer. Then more PM's came in everyday and knocked it off the first page. Then out of site, out of memory. A few slip through the cracks once in a while
Putting a 20b in a Rx-8 is not fun. I have taken measurements with a engine out of a Rx-8 and the largest enemey is the steering rack (much like the FD). But on the Rx-8 its ten times harder due to the fact its steering rack is WAY larger in diameter. So you cant just put the 20b over top of the rack and adjust everything else to fit. So it has to be shoved way back, and make a very very short lower intake manifold to tuck it all in. Shorten the pp frame, shorten the driveshaft. Mod the shifter location on a FD or FC tranny. FC will be easier to do, but none are easy. Then build custom engine mounts. And this is all in speculation, I never did the swap yet.

Now seeing that you need more information in the area of n/a 20b's, ask me anything you want. 350rwhp n/a is not very easy. There are bridge port n/a 20b's and a p-port 20b's that are street driven making 300rwhp. A few years ago my car made 348rwhp with ITB's and a streetport. Recently tried a stock intake and made 313rwhp. I can put you on the right track, but alot will have to come from your own research with trial and error dyno time. Gotta keep some cards close to the chest if you know what I mean My best advise is to initially use medium to small street ports. Very big ports are not a key to large power. If going ITB's, 50-55mm is a good place to be. Use the 9.7:1 rotors for the best cost/power ratio. The stock oil system lacks on the 20b. Revs over 8500 with race clearanced bearings will result in a drop of pressure. Stock apex seals work very well and are safe below 8500 rpms. To make over 350 wheel, your going to need over 8500 rpms. Make sure you have the rotating assembly fully balanced. The difference in a 8500rpm 20b and a 10,000 rpm 20b is more than double the price. I would wait on aluminum side housings and invest in carbon body parts or other sweet parts for 7.

Originally Posted by Falken

Hi, thanks for the reply.

On the issue of engine mounts, I think I might have it covered - there is an RX8club member who has done a turbo 20b swap who says he would be willing to fab up some mounts with me. I'll ask him what he did with the steering.

Correct me if I'm wrong - the reason I thought I would end up with a big streetport is because of the revs. I agree I need those type of revs to obtain my power goals, and I always thought that there was no use revving that high if I don't make any power up there, which would require big ports.

Other than that I've had the same general ideas. ITBs, 9.7 rotors...I was going to go with ceramic seals and a dry sump too.

I wonder if it's worth going with modified RX-8 rotors, apparently gmonsen has found success with them and he was seeing 350s.

As for price, I'm trying not to think about it yet I figure I'll figure out what it would cost to do it ideally and than subtract what I can afford to lose from there.

Thanks,
-Brandon

Originally Posted by GtoRx7

A large street port will not support any more revs than a medium will. There will be LOTS of people to dispute that, but the port shifts power only so much. The intake and exhaust will do the rest. A street port is good up to about 9k, and will just make broad power at 10k. It wont make any more peak power after 9k. But its really about the power under the curve anyway. With a street port only I would say your limited to 350-360rwhp. If you go with a bridge port, semi p-port or full p-port you can get from 370-460rwhp. The later being completely too loud for the street. Only one turbo 20b swap in a Rx-8 I've seen kept the stock steering rack. And that was done by mazsport. Everyone else has used a FD steering rack and shoved it down. Not the best method in my book, but it works to a degree.