Parastie

I saw aluminum side housings on RB's website. Has anyone used these on a street car? And is the weight loss really worth the money?

banzaitoyota

got ~ 2500 apiece?

Impreza2RX7

I bet they would warp like a SOB too..

NZConvertible

It's about $4000 for all three and you save a total of about 40lb. You have to ask yourself if $100/lb for weight reduction is sensible spending on a street car probably worth less than that...

They do not warp. If they did, nobody would buy them and RB wouldn't still be making them after all these years.

Impreza2RX7

Thanks for clarifying that NZ, for 4K you could spend alot of money on getting rid of unsprung weight anyway..

Mr. Gadget

WRONG WRONG WRONG

Your comments serve only to mislead those that might be interested in this product.

First hand info:

THEY DO NOT WARP!

Impreza2RX7

Did I or did I not say that NZ clarified that? That was my guess, nothing more. BTW, does anyone know the melting temperature of aluminum, I'd like to know just out of curiosity..

pyrojunkie

It has been posted by the mods time after time after time, if you don't know, DON'T guess. You only do more harm than good.

Aluminum's melting point is 660.37 °C (1220.666 °F). Not really a concern in this usage.

drago86

It's more like 50 lbs i think. While thats not really significant in an Fc, think if you were installing the motor in an aircraft, or lotus europa, or dune buggy or something else super light,.. it could possible be worth it to someone.

Mr. Gadget

ummmmmmmmmmmm...... yes, do i own a set, yes I do!, do i have first hand info, yes


Its not just the melting point of Aluminum that plays a part (just so I don't offed you I will not restate Pyro's info), the housings are treated and I quote directly from the RB site:

"After each aluminum housing is cast, using A356 Aircraft Alloy, it is heat treated to “T-6” hardness and then CNC-machined prior to being flame-sprayed and ground to a final finish. The greatly increased wear resistance is the result of this aerospace originated flame spray (or plasma spray) process that imbeds into the wear surfaces a proprietary carbide material whose durability greatly exceeds that of the nitride surface found on the stock cast iron housings."

I have found that the housings are real sweet (if you have the spare cash). I also suggest that if someone were to buy the housings, don't go cheap with the balance of the engine, these are for real hardcore buildups.

(Pyro - thanks for your comments, supporting my lashing out at misinformation!0

Impreza2RX7

Ok, I'll be sure to use them on a hardcore build-up of a N/A RX-7 like you did. I personally wouldn't trust them on a Turbo rotary and I would just put the cash where it would be better used, like a nice turbo and coilovers..

FC-chan

I'd love them, but I'm not intrested in p-port...

chumma7

mr gadget.. does the engine sound different?
did you also use the super lightweight rotors racing beat sells?
also.. how does the engine rev? (if you used the super lightweight rotors)
all alum engine + superlightwieght high comp rotors would make an awesome na engine

neptuneRX

yum, racing beat

TURBO FC

i dont think they made them out of aluminum to save weight.

Parastie

The end of the page says they will be built to your specs, so you do not have to have the P-port. I was thinking this plus the ultralight rotors and some kind of forced induction.

Mr. Gadget

ok, so then why did hey use Alu?

Snrub

iTrader: (1)

Mr. Gadget, could you elaborate on your setup, why you chose the housings and what you do with your car? Sounds like you're doing something interesting so I'm curious. Thanks.

Mr. Gadget

car was built for the strip - ran the **** out of it - blew it up a few too many times so I got out of it for a while. As my wife put it - "might be cheaper to be married to a drug addict."

now I take great joy in restoring rx-7s and ripping those that make comments without facts to base them on.

(nice to be old and done it all once or twice...)

Carl Byck

So, are your old plates for sale???

Mr. Gadget

nope, bought them used in the first place - in fine shape. haven't decided what to do with them (however, I will be keeping them for me!!!!)

Maybe some radical motor. Will decide after I finish my big dog!

PilotSi

How much does a bare-block 13B weigh?

I'm glad someone brought this question up, because I asked this in Rotary Tech, but I didn't get really good answers. Even better to have 1st hand experience.

Although 40-50lbs dosen't sound like much, it's all about relations. If a bareblock 13B weighs in at 300lbs (I think??) then a -50lbs is a very big change.

I guess my other question is, how come Mazda didn't do this from the factory? To me, it is similar to a piston engine with an Iron block. Why not go with Alu?

David

NZConvertible

You're right, it is all about "relations", but not to the weight of the engine. When compared to the weight of the car (which is all that matters), it's a tiny percentage reduction for the money. You could lose the same amount of weight for free simply by removing stuff. If you have a light car car to start with and you're trying to get lighter for racing, then these would make more sense. But for a street car that's relatively heavy to start with, the benefits are not worth the cost.
Cost.

Snrub

iTrader: (1)

Mr. Gadget, basic specs on your drag car?

As for why it isn't done from the factory I'll say this: When the rotary was the talk of the automotive world in the 60-70s the reduced number of parts ment assembly costs would be substantially reduced from a piston engine. As technology has advanced robots assemble modern engines. Because the rotary is essentially low volume Mazda has not invested in as many efficiency techniques in terms of having robots do stuff. It doesn't make sense to spend billions on high-tech assembly when they're not going to make money off the rotary. While it may seem like a cop-out to not have aluminum housings, especially since the rotary's advantage is high power for small size & weight, from a financial standpoint Mazda probably shouldn't bother making the rotary anymore.

Mr. Gadget

drag car is dismanteled and gone. Don't like talking about what would have been.

As for the question of whay Mazda does not use Al form the factory. The cast housings are easier to produce in quanity/quality. NZ is right, it is cost based on the two points I mentioned. I had asked them this very question during a factory tour I took while in the far east. The tour guide refered me to an engineer who basically said cost. If they sold 200,000 a year they would produce a "sport" model that would fulfill all of our dreams. So lets all buy an rx8 today!