How much can the Rx8 Engine take?
#1
How much can the Rx8 Engine take?
I would love to turbo or even supercharged my 8. But when ever I read up on great HP increase I always read about something bad thats happens to the engine. Would love to make 300+ whp but from a lot of reading it seems very hard to do so without hurting the car. Was wondering if you guys know of a way to get that kind of hp out of the car safely. I have about 6k saved up for parts to make a limite on how much to spend.
Last edited by RobRx-8; 02-11-2007 at 12:56 PM.
#2
Originally Posted by RobRx-8
I would love to turbo or even supercharged my 8. But when ever I read up on great HP increase I always read about something bad thats happens to the engine. Would love to make 300+ whp but from a lot of reading it seems very hard to do so without hurting the car. Was wondering if you guys know of a way to get that kind of hp out of the car safely. I have about 6k saved up for parts to make a limite on how much to spend.
#3
The best answer is not much. Adding up all the little things like CAI, RB Flash, high flow Cat, and a light flywheel you might see an equivalent of +20 HP. (The flyweheel doesn't add HP but on a Wheel dyno it shows in lower gears). Beyond that you'll need FI. Most people here know that much if they've read a bit.
Add some $6 a gallon T105 and you'll probably see another 8-10 HP after the ECU has learned the fuel. Extra oxygenation is most of the reason for that.
Nitrous is the poor man's FI, but you'll really want to add a piggyback tuning unit and know how to tune it.
Superchargers would be cool but no one makes one thats readily available, at least for a resonable cost. You could get a decent aftermarket shop in any big city to add one for about $3000, and plan on another $1500 for the tuning.
FI has two drawbacks; First the injectors don't flow enough fuel to satisfy high RPM boost. You could replace the injectors to overcome that but it doesn't seem to be very common.
Second the compression is too high to really get enough boost without detonation. Some people say they can and have done this, but until there are enough people who've done the long term testing with consistent results I'll remain cautious. Popping a motor every 30,000 miles wouldn't be acceptable IMO.
Considering the sales numbers I don't see Mazda putting a 3 rotor with sequential shut down anytime soon. Thats really too bad since it would probably solve part of the fuel economy issue and definately put the power level where it needs to be. Unfortunately they wouldn't sell that many more to make their money back.
Add some $6 a gallon T105 and you'll probably see another 8-10 HP after the ECU has learned the fuel. Extra oxygenation is most of the reason for that.
Nitrous is the poor man's FI, but you'll really want to add a piggyback tuning unit and know how to tune it.
Superchargers would be cool but no one makes one thats readily available, at least for a resonable cost. You could get a decent aftermarket shop in any big city to add one for about $3000, and plan on another $1500 for the tuning.
FI has two drawbacks; First the injectors don't flow enough fuel to satisfy high RPM boost. You could replace the injectors to overcome that but it doesn't seem to be very common.
Second the compression is too high to really get enough boost without detonation. Some people say they can and have done this, but until there are enough people who've done the long term testing with consistent results I'll remain cautious. Popping a motor every 30,000 miles wouldn't be acceptable IMO.
Considering the sales numbers I don't see Mazda putting a 3 rotor with sequential shut down anytime soon. Thats really too bad since it would probably solve part of the fuel economy issue and definately put the power level where it needs to be. Unfortunately they wouldn't sell that many more to make their money back.
#4
Originally Posted by kartweb
The best answer is not much. Adding up all the little things like CAI, RB Flash, high flow Cat, and a light flywheel you might see an equivalent of +20 HP. (The flyweheel doesn't add HP but on a Wheel dyno it shows in lower gears). Beyond that you'll need FI. Most people here know that much if they've read a bit.
Second I dont think he was asking about NA tuning due to the fact he said right at the top "I would love to turbo or even supercharged my 8. But when ever I read up on great HP increase I always read about something bad thats happens to the engine. Would love to make 300+ whp but from a lot of reading it seems very hard to do so without hurting the car."
Third, 300 is easily atainable with a greddy when you tune the car right. Hell one of my local guys who is in this group (DrifterD) is putting down 293RWHP with the greddy kit and a few upgrades.
So again, where are you getting your info about the renesis not being able to take much in the way of boost or was something misinterpreted? Im a little confused now
Last edited by Landon; 02-11-2007 at 04:04 PM.
#5
Originally Posted by RobRx-8
I would love to turbo or even supercharged my 8. But when ever I read up on great HP increase I always read about something bad thats happens to the engine. Would love to make 300+ whp but from a lot of reading it seems very hard to do so without hurting the car. Was wondering if you guys know of a way to get that kind of hp out of the car safely. I have about 6k saved up for parts to make a limite on how much to spend.
btw, drifterds car has an lot more than a few mods...
beers
#6
Originally Posted by Landon
So again, where are you getting your info about the renesis not being able to take much in the way of boost or was something misinterpreted? Im a little confused now
Tuning is a simple matter of running it rich enough and retarding the ignition enough to dampen detonation. How far can it be leaned to make more power? And after leaning it down, how much more prone to detonation is it?
Generally a good tuner has destroyed a few motors before they're really good. The problem is none of the tuners seem to admit they've got the required education. I hardly doubt that someone with a top end budget of $6000 wants to pay for some tuner's education.
Now when there are tuners who have demonstrated dyno results, customers with 50,000 trouble free miles on their tuned FI motor, and full specifications published for other tuners to share, at that point I'll believe the Renesis can consistently make a reliable 300 HP.
#7
There are a couple of companies that have been installing FI on the Renesis for well over a year now in Australia. One is a SC specialist www.rotormaster.com.au and the others are TC. eg www.mazfix.com.au
Some of their customers have clocked up many miles. The WHP they are getting varies between 290 to 320HP. One of the suppliers suggests additional dowling once over the 300hp point to reinforce the engine. Otherwise no reports to date of general structural problems.
If you want to find out more why not give them a call.
Some of their customers have clocked up many miles. The WHP they are getting varies between 290 to 320HP. One of the suppliers suggests additional dowling once over the 300hp point to reinforce the engine. Otherwise no reports to date of general structural problems.
If you want to find out more why not give them a call.
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