if its so bad to turbo a high compression n/a, why and how did greddy make a kit for the rx8? now only if they made a bolt on kit for the fc n/a.

 

I don't think they give you EVERYTHING you need to run an actually good setup. They just sell the turbo and parts and you deal with the rest of the hassle. People have done high compression N/A's, just not a lot, you have to know what you are doing.

 

The Greddy kit for the Rx-8 runs only 5psi and includes a FMU ( I believe). Why would they bother to make a kit for the N/A FC, when there is already a turbo version available from the factory?

 

RX8 (HP-6MT) 2004 T618Z intercooled type31, cast-mani, w/ plug-in emanage #11540050 $4,195.00

 

Its because there isnt a huge demand for them to make a kit for the n/a fc. As for the rx8 there is a bigger market world wide for people who would like a kit for there 8.

 

i dont know much about turbos but is T618Z a small turbo

 

They aren't exactly going to boost crazy numbers as you can see on a high comp setup. I thought they ran like 7psi though?

 

4k for 40rwhp more? Yeah I will pass on that. Mazda just needs to make that into more of a family car sports car like a turbo saab. The RX8 is weak.

 

Isn't it supposed to make 300hp? Thats more than 40hp extra.

 

Because a buyer of an RX-8 isn't a dead beat like an N/a FC owner. The 8 owner can afford 4 grand and doesn't bitch when it only nets him 60 more hp.

People here bitch when they spend 600 on 10HP(exhaust/intake mods) think of how they will bitch for a kit costing thousands of dollars.


Better yet go and ask Camden how many buyers they have for their s/c kit.

 

Go over to Rx-8 forums. There are currently 2 members ( that I know of) that have the Greddy kit, and just had it dyno'd recently. The baseline dyno before the kit was ~170RWHP. The after dyno made 240RWHP at 7psi. Thats a damn nice jump in power I think. Should be good for low 13s in the 1/4. The dyno chart was also nice and linear, and spooled ~3000rpm, and held boost till redline. I say good job

 

I think its a mitsubishi TD06-18G in Greddy speak. It a fairly decent sized turbo, definitely capable of more than the 5psi it runs in that kit.

 

Yeah that is a very nice impovement. i would be happy to spend that if I had an 8. Low 13's with a 4 door thats just awsome.

 

i spent close to a grand on the exhaust alone and im not bitching. with my current job i could afford an 8 but i still dont like how it looks just something about it makes me go .
if i was a fan of superchargers i would buy one of their kits it looks well put together.

im just trying to get an understanding of how this works. even though its only 5-7 psi wont it create major stress on a high compression engine. im a noob when it comes to turbos.

 

To oversimplify it alot, what you need to keep in check is the intake air temperature, and air/fuel mixture. You do not want preignition. ( If you dont know what that means, look it up). With boost ( compressed air) the intake air charge is alot hotter already ( pressure=heat), so even before it hits the combustion chamber, it is at more of a risk of detonating ( knock, pinging, preignition, whatever you want to call it). Thats why most stock turbocharged engines run a lower compression ratio. Again, pressure=heat. When you try to heavily compress that already superheated air, you run a greater risk of preignition. So when you are running both a higher compression and forced induction engine, you need to either run lower levels of boost, or try and combat the preignition with richer A/F ratios ( gas cools down the intake charge, as well as combusts at a higher temp). When you look at a dyno/wideband graph for A/Fs of a turbo rotary, most tune somewhere around 11:1 ratios. When you see one for a N/A, they are closer to ~13.5:1. Hopefully that will answer your question a bit, there is alot more to explain, and more that can be said, but you get the idea hopefully.

 

BTW, street price on the kit is just over $3000. It's a VERY nice kit and a helluva good bang for the buck - cast manifold, turbo, downpipe, intercooler, intake, preprogrammed E-manage with plug-and-play harness...it's everything you need. Most turbo kits need a lot of extra bits and pieces - this is a complete kit. Yes, it's a conservative kit, but you just bolt everything on and enjoy - everything's all tuned in and works great.

Greddy's not going to make an NA 2nd gen kit. Hell, most FC's are worth $3000 to begin with . There just won't be enough people that would pony up the money. But, RX-8 guys are buying those Greddy kits like CRAZY.

Dale

 

No, it's not.
It's one size bigger than their popular T517Z turbo, which is used on a lot of their Honda turbo kits.
These new turbos are designed for efficient low boost applications - under 10psi.


-Ted

 

Thanks for the correction.

 

specs on said turbo?

 

We're cheap, remember? We wouldn't spend $4000 to do it. Hell, very few people buy their upgrade for the Turbo RX-7, and that one only cost $2500.

 

It's not. This is a myth spread by people who don't know **** about engines and tuning.

Why? Because there was demand for it, and the car is considerably faster and more flexible as a result of the kit. As is usually the case in these threads, the only gain discussed is peak power. Not one person has mentioned torque, specifically the massive gain in the mid-range where you spend so much time.

How? It's called development, and is a big factor in the kit's price. It's also the reason why you know it will fit perfectly and work perfectly, which is much more than can be said about most DIY turbo conversions.

 

i agree with jason.

i bet the gains in the midrange are massive over the stock power curve. those cars are pigs in the midrange stock.

 

B/c who on here will spend as much money on their turbo as they would on their car?

 

Cartech once made a Hi-Flow 4i turbo kit for the 86-88 6-port 13B. The kit was good for 8.5psi on a stock engine, and up to 12psi on a modified block. You may be able to find a used one on E-bay.

 

In the end....proper tuning&testing.