meGrimlock

sorry to get off topic of the thread, but i agree with roddimus that the engine is probably not a city stop/go workhorse, but rather prefers the free flowing air of a highspeed track or highway. the cx-7 has the ability to sell well because the success of other crossovers like the murano has given it good chance with the competition. but engine will have its trials when the cx-7 goes on sale.

Roddimus Prime

yeah. I'd think they'd sell a TON more 3.0L V6 NA CX7's than anything else. American buyers are leary of odd new engine designs. Look at the horrible reputation the Rotary gets and lower sales of RX8 because of that. Quirky engines are for enthusiasts. Like us.

Honestly though...what would you rather drive in a CX7?

1. 2.3L DISI turbo w/ 240bhp 240tq, 23mpg, $1500 premium, more frequent oil changes

2. 3.0L V6 NA w/ 220-230bhp 220tq, 30mpg, $no additonal cost, less maintaince on proven powertrain

It just doesn't make sense to me with the exception of the AWD....However if you wanted the premium AWD it seems like you'd want a little more power to go with the added control and sporty grip.

Am I sounding logical or no?

Jay Chen Mazda

You seem little defensive.

Obviously you seem to know your cars. But you should also look at it this way. You want a high horse power SUV? Is this correct? Just as you yourself want high horse power car by adding FI. I'm guessing you put FI system into one of your NA cars? If so, you should know that its easy for an engine with FI system to go higher power than a car without.

Sure, CX7 might only have 220-240 rating... but modifying this should be pretty simple as its already turbo'd.

If you look at the history of turbo charged imports, you'll see that all of them are underrated. Since you are an expert in Mazda, you should know about rx7s. They were rated 255 from the factory but few small bolt on's it'll easily push 400HP at the engine.

Since you also seems to know about RX8, you should also know that its nearly impossible to get it to have 400HP at the engine due to lack of FI system. And because its high compressioned rotors, it nearly impossible to make that kind of power without one. This principle goes hand to hand with piston engines too. I'm a former RX7 owner back in CA. I used to track my 7 all the time. And I've never managed an auto parts store. Just had to get rid of it when I moved here 4 yrs ago. Since then, I've been concentrating on my career than cars.

So, have you owned a 3rd gen RX7? My father bought his 94 new and I got it 2 years later as my graduation gift. I had it for almost 6 years and sold it because I had to. I've also driven many many many high end sports cars (Lambo, Ferraris, 911 turbos, M3s, etc etc. Mind, it was few years back) on the track not just joy riding on the street. Great thing about living in CA. And by far 7 is the best handling car and for the money. I'm actually thinking about getting another to track as I'm making decent amount of money.

Point, as stated earlier, this engine is a great step for Mazda. They are not following other makers and just slap on V6 or V8. Yes, its cheaper to manufacture, cheaper to design, cheaper to maintain, cheaper to drive, overall its cheap!

But to be unique, it takes money. Hence, I admire Mazda for being unique in the past and hope for the future.

Roddimus Prime

I'm not defensive. The internet is a poor conveyor of tone of voice or demeanor. Ask anyone that knows. I'm super laid back.

You're only about half right though about your "bolt-on" statement. Here's what I mean:


Current (00-present) mazda ecu's are JUNK for tuning. The only way to tune them is with standalones or expensive piggyback controllers and that one mod is $500-1500 with NO increase in power...just the ability to tune for higher power. Add to that a full turboback exhaust ($700+ for 20whp), FMIC ($800+ for 10-25whp) and the list goes on and on....

Anything can be fast if you throw money at it. I was only talking stock for stock. The CX7 should've been 300awhp STOCK with racing beat tuned suspension. If it was it would be a Porsche KILLER for less than $30k. I've driven the Cayenne S turbo and it's crazyfast but it's HEAVY..it rolls...you feel the weight. A nimble AWD crossover with 300hp would easily match the $80K Porsche if not beat it.


Also, you can't compare the Renesis in the rx8 to the 13B in the rx7. The 13b has been out for several decades. It's been picked clean by specialists for 20+ years. The renesis is brand new and was designed from the start to be an NA engine. The same thing could be said of my brothers Toyota Corolla XRS. It's a 1.8L NA engine and can't hold boost for crap. However my 1986 Ford 2.3L turbo motor can make 700whp on stock internals. They are designed differently.

This new 2.3 DISI is brand new no'one knows how tuneable it is or how much potential it has. IMO it'll be a beast. I know it has forged internals and Juan at hiboost has made 508whp on a 2.3L with forged internals and a turbo. The DISI only helps to boost power even further since it only injects fuel during 15* of crank rotation so there's less chance of detonation.

p.s. I'm building a new rx7 right now. It's all motor...I'll be making plenty of power because it's designed to be all motor!

Jay Chen Mazda

Roddimus,

I'm wondering about your knowledge in rotary engines, even though you say you are building one. You say I can't compare Renesis to 13B? You do know that they are pretty much the same engine except for portings? I'm not an expert but what I know of is that Renesis has the same displacement as 13B and uses slightly higher compression rotors which could be interchanged between 13B engines. If it was a completely different engine, you cannot do that. You do know how rotary engine works right?

And your 1986 Ford 2.3L turbo making 700whp on stock internal. Come ON, 13B REW can also make 600HP on stock internal.
Your comment about ECU's. Its common knowlegde that if you start boosting higher or trying to make more power, you have to increase fuel and in turn you need tuneable ECU. NO factory ECU without some sort of tuning will make it reliable. Thats a no brainer.

And your comparison with Porsche Cayenne S Turbo. I'm sorry, I have to disagree. My dad actually thought about buying one. I didn't drive it, but he said its one of the best SUV he's driven. He actually described it as, "It almost feels like my old M3". I trust him over you since he has driven many many many high performance cars and owned many in his life time. NO way NA 300HP car will match with 500+HP, 911 Turbo SUV. Have you even seen the brakes that come with the Turbo Cayenne??

Also, you are missing the point of my earlier comment. DISI is a good stepping stone for Mazda. Its unique for a company to build a turbo charged engine in today's market. As you could see, you are comparing CX7 to $100+K SUV thats also turbo charged.

Roddimus Prime

Dude...I can't keep going over the same points over and over. You are wrong about a lot of things. This may not be your fault though. A lot of people make broad generalizations about cars that just don't always apply. I'm going to go over this one more time and then we're going to stop because this is WAY off topic for this guys thread.


1. The renesis 13b in the new RX8 is a peripheral port motor. The exhaust exits the engine in 3 ports and not 2 like the older 13b's. The exhaust gas also has to make 2 90* bends to get into the collector. For this reason it does not flow as well on the exhaust side as the older 13b engine. The intake side is MUCH better and flows tons more than the older 13b due to its completely different design (made for NA). The principle in how the two engines work is the same but they are NOT the same engine. One is deisgned to be an NA engine....the other is designed to be a turbo engine. Obviously one of these two is going to work better with a turbo.

2. your comments about the ecu are so elementary and obvious with lack of detail that I highly doubt you know what you're talking about. Maybe there's a language barrier difference but I get the feeling you either don't know how to communicate what you're wanting to say or don't know the right thing to say. I never said that you could boost higher or make more power without an ECU upgrade. What I said was that Mazda ECUs are JUNK for tuning requiring EXPENSIVE upgrades and not just simple modifications. If you had any experience tuning a ford/gm you'd know what I'm talking about. Ever since the horrible FD reliability hit US shores Mazda's taken a bath on warranty claims and in turn has basically locked out all forms of simple tuning. The ECU's are not easy to mess with and without buying piggybacks or standalones you're pretty much left with few options as far as tuning goes. If you're such a smart RX7 guy you should know that 99% of everyone with a modded FD runs the Apexi PowerFC. How much do those cost? $1k-1200?? Why don't they just buy a $200 FMU and increase fuel pressure with boost? Now do you see what I'm getting at? With my fords I can just throw on a bigger MAF, bigger injectors and a superchip and make as much power as I want. Some cars are just easier to tune for more power...mazda is not one of them.

3. so sorry you dont trust my opinion on the Cayenne S. As the only person in the "room" to actually drive one at 120mph I feel I'm pretty capable of saying what it feels like. I felt more body roll in it than in my p5. That's to be expected from a tall SUV. What I was getting at was that a smaller, more nimble CX7 with 300awhp (i never said NA) would easily keep pace with the heavier Porsche. There is more to speed than just horsepower and the size of the brakes. Also, you don't know what you're talking about and it's real clear when you call the Cayenne SUV a "911 Turbo SUV". I have no idea what that even means. The 911 has NOTHING to do with the Cayenne. It uses a 3.6L Flat 6 mounted in the rear with twin turbos while the cayenne is a front engine twin turbo V8.


Lastly, The DISI IS a good starting point but that has nothing to do with my original comment about the CX7s lost potential. It's rare for manufacturers to build turbo cars today?? That's odd...

pt cruiser turbo
srt 4
any porsche
vw gti
vw tdi
any diesel truck
lancer evo
subaru (just about all models)
volvo T-series cars
upcoming DISI turbo engines from GM on the solstice and Sky.

I'm not comparing the CX7 to a $100K suv....I'm saying if Mazda had played their cards right they COULD'VE competed on an even plane with them and yet again....I'm right. Sorry man.

dudeondacouch

the gloves come off early this morning...

Jay Chen Mazda

Classic. No wonder Alabama is view the way they are viewed.
Completely un-necessary comment.

You R right! I'm Chinese and I know nothing about cars.

ShadowX

Holy flame war Batman, all of that was completely off-topic...so back on topic

There's also the Hass Turbo kit, which is making more horsepower than the HiBoost. (Not saying it's better, the HiBoost has longer reliability record than Hass right now.)

Hass also offers water injection with their kit, along with a few other 'options'. They're using a Garret turbo instead of an IHI and their BOV is a recirculating type from a Porshe 911 Twin Turbo. And you don't have to tap the oil pan for the oil fitting, they use a banjo bolt instead.

Here's the link to their store -> http://www.hasspower.com/catalog/mazda.html which has NO info.

Here's a link from Mazda3Forums that has a good comparison of the two -> http://www.mazda3forums.com/index.php?topic=26859.30
The 1st page also has pricing and more details on the kit.

Roddimus Prime

If you thought that comment was harsh you're going to have to grow a thicker skin....I was being nice.


ShadowX, I've looked into the Hass turbo kits for my brothers Corolla XRS. It looks quality but don't be fooled by some of the pieces.

1. Who cares if they're using a garret turbo instead of an IHI? They both are good blowers and make plenty of power.

2. that "911 bypass valve".....I have about 10 of them here in my shop. They are about $35 a piece. They are only mildly better than your standard plastic Bosch unit. The only advantage is they're metal and not plastic.


THIS THREAD WILL BE BACK ON TOPIC....end of discussion.

Jay Chen Mazda

Its quite funny since you were the one who turned this topic into how mazda did such a poor job on CX7.

And I was mearily saying Mazda is unique in that they are using turbo charged engine in SUVs.
If you are a Mazda fan, you should knowledge that fact.

ShadowX

Roddimus, at no point did I imply that any of the parts on the Hass kit were better, I was pointing some major differences in parts. I figured pointing out the BOV was different because this kit isn't going to offer the loud BOV sound most often associated with an aftermarket kit.

Roddimus Prime

yeah, I understand you....I was just pointing out that some companies try to make it sound like their included componants are better than others when they make no difference.

The SC kit I designed uses a Bypass valve and still has a little of the whoosh noise that everyone enjoys. What I do is vent to atmosphere ALL the time and only close it under a load (boost) then when you let off to shift it vents again. Sounds pretty neat. You get a fan-running noise at idle.

ShadowX

I personally like the sound of the Bosch units, especially vented. Sometimes it's annoying having the F&F BOV on your car.

Roddimus Prime

yeah....when I was designing the kit and mentioned the bypass some people complained about not having the sound. I personally don't care....function over form is my motto.