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.

Landon

This is a rather loaded question but structurally the engine can take quite a bit if you tune it correctly (and take care of it). Lots of people have issues with the greddy turbo kit but that’s more so because the kit isn’t the greatest out there and was rushed to market. With some of the more pricy kits you get serious gains without as many problems you do with cheaper kits but be prepared to pay some serious cash. Remember you got to pay to play when it comes to this car. A better person to answer this question is the moderator named "Rotarygod" but before going to that level do a quick search. I know I have seen a thread around here talking about the structural integrity of the renesis engine vs other 13B engines.

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.

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.

Landon

1st - Where are you basing your info on this engine not being able to take much? The renesis is a damn good engine that can take boost and generate the HP he wants. He just has to be prepared to pay the cost of the upgrades

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

swoope

iTrader: (5)

i would take the time to read around for a while... lots of info here.. not one simple answer...

btw, drifterds car has an lot more than a few mods...

beers

kartweb

The Renesis can take a lot of boost for a short while. Its not a question of how stout the components are, its more about how much detonation can it endure. I've seen impressive numbers posted. I've seen some turbo owners brag of getting 30,000 miles so far. I haven't seen both.

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.

Roxy8

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.