Two companies are now building aluminum blocks that will reduce the weight of the cast iron 490 Lb small block Chevy to 390 Lbs.

Hekimian Racing makes a block that can be bored up to 455 Cid and all factory accessories bolt on for $4000.00

Chevrolet is producing the 5300 Vortec in aluminum for its line of 2004 vehicles
290 Hp @ 5200 & 325 Tq at 4000 with oil change scheduled at 10,000 mile intervals and first service at 100,000 miles.

Based on a rotary engine weight of 337Lbs:
The average battery weghs 30 to 50 Lbs, relocating it to the rear hatch, the weight on the front suspension will be increased by...10 to 30 Lbs.

 

How much do these engine's cost? Ten dollars says I can rebuild and port the hell out of a rotary for cheaper and get to 290 hp and 325 Tq.

Nice find though. 100lbs less on that block is pretty significant!

 

i doubt youll get 325 Tq outa a wankle with just 290 HP

 

No actually I would have much more HP!

 

But it would mainly be down low.

 

Is that based on shortblock weight or longblock weight? An '87 TII engine in shortblock form (no manifolds) weighs in at 200 lbs or thereabouts (according to the shippers who shipped me mine). I find it prett hard to believe that with 2 headers, 2 heads, and all other accessories it only weighs 60 lbs more than a 13bt

 

Being someone who has done a V8 conversion and also being someone who is running a website promoting the V8 RX-7 concept .... this is my opinion:

The newer Chevy LS1 is an all aluminum V8 (about 350-400 HP stock) and there is a couple of RX-7s that I know of that have LS1 motors in them. However, most of the arguments over RX-7 V8 conversions are from people who simply don't like the idea of anything other then a Rotary engine in a RX-7 so I suspect the arguments are not going to stop.

My biggest problems with the whole V8 RX-7 concept is I don't like referring people to Grannys Speed Shop for the V8 conversion parts because I hear a lot of horror stories about Grannys and their products (I also had problems with Grannys).

 

<~~~ doesnt like v8 swaps ... its kinda like ruining the heritage of the RX series..... and all that time those people in japan did the research for years to get it to work... same with the germans.... to me it feels like your disgracing the cars soul.... oh well thats my opinion

 

<--------- hates v8 swaps also


-Shawn (v8 swaps are for people who are scared of the big wankle)

 

If you move the battery to the rear of the car how is wieght increased on the front end?

 

Ah heck. To each there own. I am drawn to the RX-7 for it being unique. And I would have to say a RX-7 with a V8 is unique. At least if you do the swap you know they are automotive enthusiats. Which is more than I can say for some of the wankel engined rx-7 owners i have meet.

James

 

"Almost immediately after taking over the RX-7 program, Kobayakawa began work on the next generation. And while there was total freedom over the powerplant choice for the new sports car, the rotary was selected, first for compactness and power potential, but also for heritage. Said Yamamoto: "To forsake the rotary would be losing our identity. The RX-7 could not and would not exist without the rotary"

hmm...

 

The new posts........ support my point above.

 

im only gonna post once here because i have had this argument so many times before.

V8 RX-7's are an issue that will never have a one-sided argument. personally I would only convert a Vert to a V8 (mainly due to the fact that it is a heavy beast), but V8 Rx7's are just as fast, unique, and time consuming as the regular. the rotary will never die or go away completely and there are many many people who love the rotary, so we dont need to worry about rx-7's becoming extinct or all v8's.

i guess i feel this way because i have 3 7's and when you have had your fun with the wankel, a V8 rx-7 is quite intruiging. i think rotarists should be honored that the Rx-7 is the subject of many V8 swaps. it proves that, not only is the rotary engine a work of genius but the car it primarily resides in is a piece of genius as well

Justin

 

YA CHevys LS1s suck ***! I HAD a Camaro Z28 with a LS1 and it could not even pull a full car length on my friends NA 91 RX7. Not to mention GMs usuall problems with their electronics. The six speed was ok but the skip shift was annoying as hell. Also 290 HP from a big *** V-8 is horse ****. **** poor performance and I would expexct nothing less from GM but **** poor performance. Ok lets see Honda has 2.0 NA thats putting out 240 HP and now Mazdas RX8 will be putting out 250 HP N/A so what the hell GMs got all those cubes to play with and the best they can do in stock trim is 290 LOL Man that is funny. I got a idea GM should just close up shop and do the whole world a favor by not selling there crap products anymore. Oh ya where is 1/2 there motors assembled now? Mexico and the other 1/2 Canada. Not only do they rip the American public off by selling junk cars to the working man but they fire a good chunk of them and move assembly plants to Mexico for cheap labor. Yet the cost of labor goes down but the price of the car still goes up, plus the cost of ownership goes up because of high maintenece on their junk products. Ya know when I think of high quality products and especially cars and where they are made for some reason Mexico does not pop into my head. I guees when I think of high quality craftsmanship I think Japan, U.S. and then Germany. So take your low tech aluminum cast blocked V-8s and throw em in some Impallas and sell it in Mexico. We dont want your crap and you won't sell ****. Imagine a 5 liter rotary? It would mop your V-8 **** up right now. DUMB ***. Please sombody quote me I love that ****

 

Funny you should mention problems with electronics. Does ANYONE have a wiper switch that works right?

Also let us not forget that that 290lbs is backed with a large 350+ ft lbs of torque that will get your car moving ina hurry.

PS If a LS1 Camaro pulled on a 91 N/A, that Camaro must have had both head gaskets blown, dropped 2 pistons, and have 2 flat tires.

Either that or you are full of something. BS meter anyone?

 

A LS1 6spd Fbody should be a VERY low 13sec car. If you can't pull a NA RX7 with 160hp, you can't drive. I like V8 RX7's, when my motor pops (and thats not IF but most certainly WHEN) I will seriously consider an LS1 swap.

Daniel

 

I'm actually still curious about the weight of a longblock V8 compared to a longblock 7. When I say longblock I mean a totally stock TII with emissions control, compared to an aluminum block with heads, emissions and headers. I'm not bagging on anybody or their projects/cars, I'm just curious.

-David Guy
Andern Research Labs, LLC.
dguy@andern.org

 

Yep....you are a dumbass. LS1's suck???? are you on crack? Ls1's in the new vette make OVER 400 HP. YES repeat that with me again.... 400 HORSEPOWER. That is nothing to laugh at. I would also like to see this 240 hp honda engine produce more then 200 ft/lbs of torque that you are talking about. And whats this about you couldnt pull on a Na rx7??? you know there is more then 2 gears in a 6 speed right? Your whole post just proves your stupidity.... here you go. this should be good enough for now.

-Jerry

 

Mine works just fine LS6.

 

does it seem to anyone else that the Marines are an angry bunch of folks.....what was it my dad used to say... Utah State Motorcycle Club??? Uncle Sams Misguided Children???

Justin

 

what about weight split???

With the V8, 80 percent of the weight is above the crank as opposed to the rotary which is closer to only sixty percent above the crank.

so all you V8 advicates, how do you compinsate for the change in center of gravity???

Even if you add/replace all the extra parts to make the V8 light enough that it changes the weight to maginally close, what to you do about the center of gravity shift???

Or again is straight line drag performace the only thing V8 conversion people are intrested in???

 

I have a 5.0 RX, it was either that or it was going to the crusher, so sue me.

 

Tell me again why I need all that torque to move a sub 2800lb car?

 

One thing to keep in mind about stock (from the factory) horsepower ratings... They don't mean squat. Does anyone care that a stock Camaro makes xxx hp? or a stock RX7 makes xxx hp? Yeah, maybe the first week you own it. My point is this: Everyone who buys their cars for performance reasons, always has the next mod in mind -- and more often than not, that mod is a HP mod...

Keep in mind that the factories crank out passenger cars to be basically on similar levels of performance -- I mean within the same class of car. The factory does not build a motor to it's potential. I don't care if it's Chrysler, GM, Honda, or Mazda. They build it to a level of what they see as extreme reliability, some degree of efficency (MPG), while still maintaining somewhat of a performance edge on their competitor(s).

So to compare a 2.0 Honda to a 350 GM while both make the same horsepower doesn't really mean much... I applaud Honda for getting the same results from a smaller package. But keep in mind there are people who would own nothing less than a V8 in a domestic car. (Including me except for my FC). It's all about marketing . . . Remember back to the 60s when motors were cranking out 400 HP STOCK, and the factories were CONSERVATIVE with their HP ratings -- read: they made more than advertised! Why? Marketing strategies...

If we saw factories build to the limits of their engines, there would be no fun for us. We wouldn't be able to mod without seriously comprimising the reliability of the engine -- and most of our results would probably result in very small improvements.

Sorry for the longwinded post, but my point was that comparing stock ratings doesn't really mean much to most enthusiasts because of what we have planned for the car. Although I have seen some extremely powerful small displacement motors, there is no denying the Torque and HP potential of bigger displacement engines. Right now, those bigger displacement engines are piston engines. I'll freak (and applaud) the day I see a small displacement Honda or Mazda (or anything) run the quarter in 4 seconds... I'm not saying it won't happen, but based on today's technology, it's not possible (or at least no one has figured it out).