quote

" Engine Weights:
Mazda S4 13BT 171kg/376lbs (Brian long Book pg 84)
Mazda S4 13B 153kg/337lbs (Brian long Book pg 84)
S5 13BT full drivetrain 388kg/854lbs (3rd gen Yamaguchi book pg 110)
Full S6 drivetrain - including PPF 379kg/834lbs (3rd gen Yamaguchi book pg 110)

I cannot find official, reliable engine weights for the S5, S6 and Renesis engines, so I have calculated them using reasonable assumptions.

Mazda S5 13BT Drivetrain Minus Engine Estimated Weight Calculation:
388 (S5 drivetrain) - 171 (S4 13BT engine) = 217kg S5 turbo drivetrain (the this weight is likely slightly low seeing as there are some small known weight savings with the S5 vs S4 engine such as the rotors and flywheel)

13B-REW Engine Estimated Weight Calculation:
379 (S6 drivetrain weight) - 217 (estimated S5 turbo drivetrain minus engine) = 162kg/356lbs Maximum possible engine weight. (Estimated maximum given the fact that the transmission is likely nearly identical to the S5 and considering the added weight of the power plan frame it is likely the 13B-REW weighs less than the quoted figure. Also the S5 drivetrain weight minus engine was estimated in a manner that raises the estimated final engine weight)

Esimated Renesis Weight
80lbs lighter than the 3rd generation RX-7's 13B-REW. (Renesis Rotary Engine Design Technology: Technical Training Program, "Renesis Rotary Engine" Module 3. By Mazda - It's a Flash presentation designed for Mazda mechanics)
356 - 80 = 276lbs/125kg

Honda 2.0L S2000 Engine weight 158kg/348lbs (http://www.autoexpress.co.uk/?http:// ... e_news_story.php?id=37079)
Chevy LS1/LS6 497 lbs, 226 kg (http://www.corvetteactioncenter.com/specs/z06/ls1ls6.html)
Chevy (LT1) L98 600lbs, 272kg (http://www.angelfire.com/ar/dw42/engfyi.htm)
Mazda 20B 350kg, 770lbs (www.fc3spro.com) - This figure is repeated elsewhere and fc3spro.com is likely quoting these sources. I am not blaming fc3spro or the other's who quote this figure, but I have trouble believing this value because it does not make sense that the 3-rotor engine could weight more than two times a 13B-REW and more than a cast iron LT1. 3-rotor engines have a second cast iron intermediate housing that is much wider than those found in a 2-rotor, an extra rotor housing, rotor, longer eccentric shaft, wider manifolds. Hence the weight difference from a 13B-REW should be substantial, but more than two times is hard for me to swallow.

*Note: All engine weights are fully dressed wet weights. So for instance, the full S5 drivetrain would include ABS pump, power steering, air pump, air conditioning and alternator."

The weight figure for a 13bto vs ca18det shows clearly the Ca is much lighter.
151kg for the 13b NA (not turbo) vs 128kg for ca18det.
These weights are confirmed by rotary enthusiast on www.rx7club.com so allowing
50lbs 22kgs for turbo gear 13bt guise its 173kg.
The only lighweight 13b is an NA built with alloy rotor housings, minimal thin
hand carved inlet manifold and custom thin walled inconel exhaust header.
Without the header the Racebeat 13 NA is 96kg without clutch and flywheel with
electric waterpump and alloy endplate housings instead of cast iron.

If they werent expensive, uneconomical, hard to register and with ally endplates
in Victoria I would not hesitate. But the fact is they are now for deep pockets.
I used to be into them but since Mazda has made itself independent from Ford
its prices for spare parts are ridiculous.
As always pistons rule due to the X 10000000000000 more development invested in them
and the fact that its a failed architecture for F1 like rpm, top fuelers, drifting
and everyday driving.

Dont get me wrong i do love them as much as I love variety in anything but the fact is
they are expensive, inefficient and difficult to register. However for light aircraft
they rule over existing super expensive lycoming and other overpriced brands.
Also in single rotor turbo guise they are almost as affordable as a 2liter four cylinder.

rotary turbos are very quick and rev like all fuk. if u go rotary just make sure u get a proven good motor

lol if we are talking street cars then im pretty sure a modified CA18DET would catch a modified 13b... considering you cant register a 13bt

i would go the rotor, only cause when i had my CA it was a ongoing money pit, yeah i know rotories dont have good reputations but i think people who say that never drove one.. i have been around rotories for a while and the reason i went for a rotor instead of CA is i dont want full power or the quickest car on the street i wanted a cruiser for weekends that sounded like sex on wheels and i can tell you chicks love it and if the day comes i want power i can assure you no CA will ever catch a decent 13b, you tell me who has ever seen a CA with over 1000hp? ive seen rotories at that figure.... and i know a 20B rotor would fit in a datsun and put out over 500kw on standard n/a..

but its what you want to do with it...

any modified car is a pig in trafic. as for the weight of a ca18 vs a 12a ( both na engines). the rota is heaps less. how many modified cars sit in trafic and dont overheat

there is pros and cons with every motor and every modification.

if you look at all the rotor guys who have gone 2jz is the guys who own the rotary shops. example craig dyson from dyson rotary and also maztech have gone that way aswell. gas motorsport made a deal with them to run the cars

these guys have been racing cars since the early 90s. and i dont think they find it hard to find parts.

any motor cost big bucks to build if you want it done right. there is heaps of blokes who rebuild rotors on the cheap and have no drama. if they were that unreliable why would they build the rx8

Quote:

A ported NA 12a is a pig in traffic, my 12a bridgeport was fun at high revs but the 13b extend was much more fun in everyday situations it didnt make you want to rev the crap out of it like the 12aBP did. A turbo rotary is the perfect combo not an NA rotary for the street. However as mentioned earlier impossible to register in most states. The problem with the rotary now is the price of rebuilds and parts they have more than doubled across the board and most drag racers that where into rotaries are now going the 2jz. Enthusiast are not happy about the costs and neither the 2jz mushrooming effect across the drag strip.
Good rotor rebuilders and machinist are not common or have quick turnarounds.

As for weight the CA is much lighter than a rotary in NA or turbo. The rotary has a compact form factor, inefficient put supremely powerful for its size.

There are plenty of well setup rotaries and ca18det but when it comes down to
economy, budget replacement parts and ease of install and registration the
CA is way better than even an SR20det.

I have a custom single rotor 13b which Im playing with at the moment
it was in a turbo escort sports sedan with a PP housing and making 280hp.
It only came to life at 6500rpm once the t3 was at full boost.
It blew the clutch at perhaps 12,000rpm when the accelerator was stuck.
It drank fuel like a big block v8 and sounded like a virgin busted by Long John Silver.

i think you can go past a rotary. ive had 2 13bt powered 1200 utes. one i still own and one i sold. both wild as hell cars to drive. the first one i had was a standard series 4 13bt with no mods. car ran a 12.2 @118 mph quater. if i had traction i have the mph to run an 11.3. car had heaps more in it. just struggled with wheelspin.

ive driven a mates ca18det ute. my mate has had more trouble with it then any rota i have ever owned. blown head gaskets. etc

if you drive a rotary properly with good oil and good fuel supply you wont have any problems with it. unless you over rev it and dont warm it up.

with both engine packages there is enough power to beat most cars on the street and they are both fun to drive.

the issue i had with the ca18 is the shifter sits to far back in the car as to the 13b it sat forward and was easier to drive.

the rotary made power strait away as the ca was power at the top. maybe different in other cars.

even if you put a 12a in the car with porting it would still make good power. just as much as a 13bt if the right guy built it.

another plue with the rotary is that its heaps lighter and heaps more room under the hood.

each to their own i guess. hope this helps out

nah can only go 1.2 litres for rotor, all those figures are halve for what you can have for a rotor i'm pretty sure, so 2.4 piston or 1.2 rotor n/a

sr20det vct all the way