GregFD3S

Here is an LS1 FD (in the video somewhere towards the end) that made 350/380 and spent boat loads of money doing it, and my FD made more power at only 13 PSI. (sorry 'RX7what' )

Click here to see Video

Callsign_Vega

iTrader: (3)

What exactly does the displacement of the engine have to do with anything? Let's see, most people want five things in an engine: hp/torque (power), fuel economy, reliability, low weight and a useable power band.

Hp/Torque: 13b CAN make some pretty good power numbers but once you get near 500hp and over, a LSx engine can make more and at a much lower fuel octane level. Not to mention the better torque throughout the range. Edge: LSx

Fuel Economy: people think hey, 13b is 1.3 liter so it should be good on fuel. An LSx with over four times the displacement gets considerably better gas mileage. Edge: LSx

Reliability: I won't even bother here. Edge: LSx

Low Weight: Both the LSx and a 13b with all of it's turbo and accessory systems are about the same weight. Edge: none.

Useable power band: 13b with a single turbo to make big power suffers from turbo lag and non-linear power application. LSx has a smooth power output making it easier and faster around a track. Edge: LSx

Don't get me wrong, I like rotaries. I just makes me laugh when people tout 1.3liters like its some big deal when in the end it means nothing besides high revs but loses in 4 of the 5 categories.

Callsign_Vega

iTrader: (3)

I never could understand why people would go through all of the trouble to swap an engine and put a stock or near stock low power version in it. If you are going LSx, do it right and put atleast 500hp under the hood.

neit_jnf

iTrader: (17)

no problem at all jim, i love big power and the sound of a V8!


i just get tired of everybody comparing a big power 13B (comparable to a 2.6L piston and don't start fighting) with a large displacement V8...

they are diferent engines and make power differently so I don't really like to compare them.

jimlab

So I guess your single turbo setup, Power FC, fuel mods and "the basics" were free?

jimlab

How much power would your rotary engine make without boost? How much power could a built LSx make at the same 13 psi? That's what I thought...

DBZ33

Like I said before. I used to have a 94 RX7 and I know how unreliable the motor can be. I love the car but I don’t want to swap the motor every 30-60k miles. Yes I see you make over 400+RWHP but I bet you will not last long at all at that power level. The LSx motor swap is not for everyone. But for me to get back into a FD RX7 this is the only way I will do it. I am not going to deal with the reliability problems anymore.

DBZ33

Have you ever heard of a usable power band. I want lowend power not just 200RWHP @ 3k rpm and then shoot up to 400+RWHP. If I wanted that I would stick with my supra. My supra with only $800 made 400+RWHP. Go back to the 3rd Gen FD forum if you don't like people who swap to LSx motors.

GregFD3S

No, but I sure as hell diddnt spend $15K to make 450 RWHP.

Look, I am not saying that I hate people that do LSx swaps into an FD. I am just saying that its been done millions of times, and its not original anymore. Why spend all that money for relatively the same amount of horsepower?

My 2 pesos...

jimlab

The same smartass ignorant comments have been made a million times too, but that didn't seem to stop you.

Neither are 20B conversions, but I doubt you have anything negative to say about them.

I think you're forgetting the improved reliability, gas mileage, drivability, and a few of the other benefits, not to mention the fact that you're talking about a naturally aspirated platform that can be vastly improved upon before you even have to resort to forced induction. If you think 450 RWHP is the limit of LSx conversions, better think again.

Once again, worth NADA...

JDMRevolution

iTrader: (6)

Torque anyone?

DBZ33

Couldn't of said it better my self!!!

wanklin

iTrader: (2)

OK.... You can buy a full LS1 pull-out for about the price of a good 13brew rebuild and then spend nearly the same money for 8-10PSI (limit of stock internals) of forced induction, a couple thousand on chassis pieces and end up with a little more power than you are currently making. And guess what.. an 8PSI V8 setup will still be making that power while you are financing your next 2 rebuilds..... You can pay the money now or you can pay it later, but you won't get the down time back.

Dark-one

iTrader: (4)

I rode in both a single turbo 13b built up and a lsx powered rx7 with over 400 hp and must say I'd take the lsx swap anyday. I do miss having a turbo but I figure just turbo the ls1 and have something really badass. It all comes down to what your looking the car to have. I wanted a reliable and fast car so I went with the lsx swap. I'm about 80% complete.

Callsign_Vega

iTrader: (3)

Wow, talk about misinterpreting a post! I said I cannot understand why people would go through all of the trouble of an engine swap and put a stock or lower hp LSx in it. Upgrade the LSx and make it a badass. Having a 350hp LS1 in an FD is . My current prospect engine for my project FD when I get ready to buy is a Hinson turbocharger kit mated to an LS2. I think I will be staying in this forum..

rajahFD

$10k and only made 350 LMAO WOW

What'd they buy? Body kits, Custom Paint Jobs, Rims and Neon lights thinking it would add HP?

turbogarrett

iTrader: (1)

^Bolt on ls1's make 325-350 rwhp and similiar tq, what's wrong with that? My first setup -small cam, some bolt ons, made a measly(by your standards) 360/370. The car had me grinning from ear to ear for quite awhile, 119 mph trap speeds, a blast on the roadcourse etc. Point is even a lightly modded lsx fd is a fast car and not everyone is a baller(possible dreamer) like yourself and can afford to start with a turbo'd ls2........


edit; this post is in response to mr. vega not mr. rasta

rajahFD

lol

SMonty

I dont really understand why people talk about peak hp number like thats what matters. if you have 1000rwhp for 300 rpms on a dyno curve that looks like a cliff.... I dont give a ****. compare some charts guys. better yet, go test drive a corvette and feel the difference yourselves. Nobody doing the lsx swap cares what makes the car unique, its a good chassy for the swap and its not really expensive, especially the FC.

Eggie

That sounds more like an LSx than a 13B. You're talking 350lb-ft at 3000rpm.

DBZ33

The dyno below shows a single turbo Rx7 with only 100 RWHP @ 3K and @ 4K rpm not even 200 RWHP. I don't want to make this a battle between rotary and piston motors. Like I said in my first post. I love the RX7 FD and I used to own one. I want to buy another one but I don't want to deal with the rotary motor. I want a fast reliable motor with low-end power. This is my choice. I didn't ask if I should swap. This is the only way I will buy another FD. Case closed!!!!


http://www.93fd.com/gallery/main.php?g2_itemId=4935

Eggie

Exactly! Your earlier example of 200rwhp at 3k described the engine you DO want.

DBZ33

Sorry i did take your post the wrong way. All I want is a LS1 or LS2 with heads, mild cam and headers. That should be good for a 420 - 450 RWHP all motor and put me in the 10's @ over 125mph with tires. There is a guy that has an LSx swap and ran 10.89 @ 133 mph. That is what I want.

DBZ33

No I want a V8 motor that @ 3K RPM makes more than 200 RWHP. The LS2 motors with bolt on parts make 300 or more RWHP and over 400 FT/Tq at that same RPM. I don't want to wind my little 1.3L to 6-8K rpm to make power.

silicone boy

Just 420ish RWHP out of your rotary? is that all you got? I've got an LS7 in mine and it can run all day without blowing up and I've got 520 RWHP. Guess what? It's steetable and I can actually race it on the track. You probably have a single turbo making it useless for a road racer. It's probably one of those drag queens. So who's violating the RX7 tradition now? It's probably one of the greatest production road racers ever built and should be kept that way. Yeah, yeah, I know. People say that properly maintained, a rotary can last 200K miles, but properly maintained, a LS motor can last a million miles and get in the mid 20's for gas mileage.


A couple of other jabs. When my car was a rotary, it was pumping out 350 RWHP as a twin turbo, so I was able to keep it true to it's original intent--a single turbo just ruins the car for track purposes. Don't say I can't make rotary power-I can rebuild a rotary with my eyes closed. I've probably been hotrodding before you were born and I've forgotten more than you know about cars. Did you turn every bolt like I did or did you farm it out? Remember, it's about engineering, not devotion to a rotary ideal. I had a goal, and a rotary wasn't gonna get me there. Because of folks like you, I'm gonna post my build just to irritate purists. One of them told me "see ya in 2009" thinking it would take me forever. I've been running for a month and I started in late December of 06. That's just over 4 months working casually after work at nights and I had to wait for LS7 heads for 2 months of downtime. It rocks. Does it throw off the handling? Actually, I had a friend corner weight it and I have very slightly better weight distribution. It's all about the engineering, not the purism