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What is best for my 8?
Posted: Thu Aug 13, 2009 9:14
by tripodkat85
I have a little bit of money I want to put into my car. I'll be installing my cold air intake today. The wheels and tires are good already. I was thinking to do my exhaust next, but not too sure. I want to get some more speed and power if I can. I have a whole list of things I want to get done eventually, but this just my starting off point. What should my plan be? Everyone has ideas for me but they lack the knowledge of this car to be taken into consideration.
Posted: Thu Aug 13, 2009 9:14
by Ranger
At this altitude, you won't get much power just from adding an exhaust. Unfortunately the only way to make noticeable power on 8s up here is to go with forced induction. However if you are going to do that you'll need an exhaust anyway, so that's not a bad start. I don't know much about turbo kits for 8s, but there are plenty of people on here who do, so here's a free bump

Posted: Thu Aug 13, 2009 9:14
by *DarthRX8*
First off welcome! I don't think that I have seen you around here before?
If you are looking for more speed and power I would ask how much?
If your answer is 20whp more then a midpipe/ high flow cat and an accessport with a tune will get you there. The rest of the bolt ons for the RX8 (intake, pulleys, exhaust, etc.) are mostly for sound or a couple extra hp here and there, nothing substantial.
If you want to make anything higher than 200 to 210whp you will have to go FI. Nitrous, Turbo or Supercharger. IF you have the money then I would definitly do it, I wish I could.
G/L
Posted: Thu Aug 13, 2009 9:14
by Fly boy
*DarthRX8* wrote:
If your answer is 20whp more then a midpipe/ high flow cat and an accessport with a tune will get you there. The rest of the bolt ons for the RX8 (intake, pulleys, exhaust, etc.) are mostly for sound or a couple extra hp here and there, nothing substantial.
G/L
I'm not a car guru, or a ricer by any means, but wouldn't changing out the Cam give pretty decent gains? Or was that a dumb statement? :shrugs:
Posted: Thu Aug 13, 2009 9:14
by Ranger
Rotary engines don't have cams

As I recall, the only thing you can do to an n/a rotary to give it a REAL upgrade in power is to enlarge the ports. But, the larger the ports, the harder it is to keep it running reliably. And it also requires removal and disassembly of the engine.
Posted: Thu Aug 13, 2009 9:14
by Fly boy
Ranger wrote:Rotary engines don't have cams

As I recall, the only thing you can do to an n/a rotary to give it a REAL upgrade in power is to enlarge the ports. But, the larger the ports, the harder it is to keep it running reliably. And it also requires removal and disassembly of the engine.
Heh, didn't think so, but I have never delt with a rotary. Pretty neat desgn though.
Posted: Thu Aug 13, 2009 9:14
by *DarthRX8*
Ranger wrote:Rotary engines don't have cams

As I recall, the only thing you can do to an n/a rotary to give it a REAL upgrade in power is to enlarge the ports. But, the larger the ports, the harder it is to keep it running reliably. And it also requires removal and disassembly of the engine.
I know of one person who ported his RX8 (the renesis) and it only yielded about a 10whp gain. Which if you consider how much work goes into doing this it really isn't worth it.
I almost wet myself when I saw FLYBOY ask about replacing the cams, no offense FLYBOY, it was just funny!:D
Posted: Thu Aug 13, 2009 9:14
by Fly boy
*DarthRX8* wrote:I know of one person who ported his RX8 (the renesis) and it only yielded about a 10whp gain. Which if you consider how much work goes into doing this it really isn't worth it.
I almost wet myself when I saw FLYBOY ask about replacing the cams, no offense FLYBOY, it was just funny!:D
Non taken. As I was writing I was thinking that they didn't, but was to far to erase it all. Plus, We learn something everyday.
Posted: Thu Aug 13, 2009 9:14
by chickenwafer
Best mods for the money on this car is the AccessPORT + Catless midpipe.
Also look at the AxialFlow short throw shifter- it gives a real "bolt action" feel and ELIMINATES any slop and play in the gearbox. Very worthwhile.
Also don't overlook suspension, it will completely transform the car. If you think it handles good now, get a good combo of shocks/springs or coilovers and you'll be blown away!
Catback exhaust doesn't net much power, reguardless of altitude. The Mazda engineers did a good job maximizing the potential of the Renesis while making it pass emissions.
As far as porting, two people have now successfully bridgeported a Renesis, which will yield MUCH more than 10-whp gains. We haven't seen any dyno's to date yet, tho.
Posted: Thu Aug 13, 2009 9:14
by Cesaros
retro fit a front clip from the Mazda Cosmo. then you will have the most bad ass RX8 of all time.
any rotary peeps who dont know what Im talking about...shame on you! lol
Posted: Thu Aug 13, 2009 9:14
by Ranger
Posted: Thu Aug 13, 2009 9:14
by Cesaros
good find ranger. a motor worth being in the Rx8.
Posted: Fri Aug 14, 2009 9:14
by chickenwafer
Cesaros wrote:retro fit a front clip from the Mazda Cosmo. then you will have the most bad ass RX8 of all time.
any rotary peeps who dont know what Im talking about...shame on you! lol
Talk about lots of $$ haha. The Cosmo also had a weak-ass automatic transmission which you don't want.
Mad Mike's 8 is sick!! There are a few 20B 8's out there, a lot of them are in Puerto Rico tho, oddly enough. Those PR guys are crazy.
But I think the OP is looking for more realistic options, not $25K engine swaps, lol.
Posted: Fri Aug 14, 2009 9:14
by Cesaros
you can get a 20B for about 5 grand. Theres a place in cincinatti I found that sells refurbished 13B twin turbo and 20B engine.
Posted: Fri Aug 14, 2009 9:14
by chickenwafer
And then it's another $15k in custom fabrication to make it fit in a car that wasn't designed for it, custom transmission, driveshaft, rear end, new rear suspension links (because the stock ones will bend above 500-rwhp), custom new rear axles, custom exhaust, custom downpipe, custom intercooler piping, custom oil pan for clearance, custom radiator hoses, custom wired standalone EMS, whole fuel system and fuel rails, new fuel pumps (you will need two), AN fuel hoses, AN fittings (lots), FRP, new shiny turbocharger, custom intake, custom powerplant frame (plan on $5k for that alone unless you can make it yourself)....
You will also need a power steering rack from an MKIV Twin turbo Supra since the stock one won't fit, custom tierods, etc
Of course once you have that power you'll need better brakes, so a BBK is in order. New wheels, tires, and the stock suspension will squat hard under the power so coilsovers, sway bars, etc.
Trust me, I've helped a 20B swap on an FC, and it's WELL over the cost of the engine alone.