jimlab

I guess it's time to haul out the "proof of concept" graphs again...



Naturally aspirated, pump gas, lightweight car. Any questions?

the_glass_man

iTrader: (2)

I notice there isn't a three rotor graph on there. Only fair.

jimlab

How so? Because so many of you have 20Bs? I fail to see how it makes the comparison "fair", but if you insist...

the_glass_man

iTrader: (2)

Q: How many people have 396's in RX-7's???
A: None.



A 20B is as much of a "drop in" (if you want to call it that) as an LT1 engine. If you are going to increase displacement its only right to include other options as well.

jimlab

Even if the graph only included the LT1 and a stock 13B-REW, the comparison is valid. The comparison is NOT the increase in displacement, the comparison is the increase in power over a known baseline.

The comparison is even more valid if you add the "Modified FD", which is Brooks' Weisblat's previous 364 RWHP stock twin car. This comparison is especially meaningful to FD owners with stock twins, since they're more than likely making power somewhere between stock and Brooks' curve.

For the comparatively few single turbo cars, Rice Racing's dyno results ("13B T04S") is extremely relevant. It also indicates just how "bad" (from a street perspective) the power curve of a high horsepower single turbo 2-rotor can be, in my opinion.

Note that the torque and horsepower are actually lower than the twin turbo engines until power starts to climb at 4,500 rpm? This is a text book illustration of the short comings of modifying only for high end horsepower with a very small displacement engine.

If you want a 20B thrown in to compare displacement vs. displacement, then Chito Solomon's FC with a T64 20B is the best example I could find. The 3-rotor certainly does make a lot more torque than the 2-rotor engines... but not compared to a small block V8, especially below 4,000-4,500 rpm which is where street engines operate most of the time.

Peak numbers are fine for bragging rights, but averages tell far more about how broad the powerband of an engine really is.

Peak RWHP
221 @ 6,500 - Stock FD
364 @ 6,500 - Modified FD
519 @ 7,500 - 13B T04S
458 @ 6,500 - 20B T64
551 @ 7,000 - NA 396 LT1

Peak RWTQ
200 @ 5,000 - Stock FD
299 @ 5,500 - Modified FD
386 @ 6,500 - 13B T04S
434 @ 4,500 - 20B T64
473 @ 5,000 - NA 396 LT1

Average RWHP (2,000-8,000 rpm)
155 - Stock FD
231 - Modified FD
286 - 13B T04S
319 - 20B T64
396 - NA 396 LT1

Average RWTQ (2,000-8,000 rpm)
161 - Stock FD
228 - Modified FD
268 - 13B T04S
320 - 20B T64
413 - NA 396 LT1

Average RWHP (2,000-4,500 rpm)
102 - Stock FD
116 - Modified FD
112 - 13B T04S
185 - 20B T64
254 - NA 396 LT1

Average RWTQ (2,000-4,500 rpm)
156 - Stock FD
178 - Modified FD
172 - 13B T04S
273 - 20B T64
399 - NA 396 LT1

Maestro

Then why would you want to mess up the 50/50 weight ditribution in the RX-7.

I'm sorry but I think a Rx-7 should be kept a rotary. Besides V8's are primative !

the_glass_man

iTrader: (2)

Until its in the car and moving on its own power, putting down real numbers I'll reserve judgement.
Taking numbers from dyno graphs and plotting them for baseline comparisons is fine, but just comparing run of the mill 13B's with a fully built LT1 engine doesn't seem like a very good comparison.
Maybe you should compare a stock LT1 as it comes, compared to a bolt on car like Brooks or Rich's 368 RWHP???

jimlab

Who said anything about messing up the 50/50 weight distribution? Do you expect me to believe that you know more about it than I do? This topic has been covered ad nauseum... look it up in my V8 conversion thread if you're interested in the truth.

But while we're on the subject, do you really know what static 50/50 weight distribution really means, or are you just regurgitating it as something you read which was supposed to be one of the "good" things about the FD? Furthermore, do you realize that it isn't necessary to have 50/50 balance to still have a car that handles very well? Do you (and others) know what effect you're having to the 50/50 balance of the car when you pull off things like the catalytic converters, relocate the battery, add a larger intercooler, throw in a stereo, or change the suspension (spring rate, sway bar stiffness, etc.)? And finally, you do realize, of course, that weight distribution is constantly changing the entire time the car is in motion, don't you? Just curious about what you know on the subject...

Um, OK. That's "primitive", by the way.

jimlab

Real numbers? I guess engine dyno numbers aren't "real"?

Putting the engine in the car won't change anything. Drivetrain losses (15% calculated into the numbers above) aren't going to magically drag my engine down to "rotary level".

Those number were attained using only the base maps, by the way. My engine hasn't even been final tuned yet. The comparison only gets worse, not better.

Run of the mill 13Bs? Many people never attain the power levels of Brooks Weisblat with stock twins, and most will never have the power of Rice Racing's single turbo car. How are those "run of the mill" 13Bs?

Maybe I should compare a stock LT1 to a stock 13B-REW?

Why should the V8 be stock and the rotary modified? To make the rotary engine look better? Add heads and a cam to the LT1 and then it's a valid comparison. Or how about we compare a stock LS6 to a modified 13B in the same chassis? Better yet, let's bolt on a supercharger which costs less than a single turbo kit for the 13B, and then let's compare "bolt-on to bolt-on".

twint78

jim and john i cant believe i havent received any hate messages.except one.im on a roll.but jim why waste ur breath on these ppl.ur just a whispering echo fading into the darkest corners of a rotarists mind.u keep telling the same ppl over and over and over about the same topics.no they dont understand 50/50 weight distribution.jim as much as i hate to say it.rx7 owners are just older and richer ricers.

50/50 yo/what about rearranging?something ricers would say and get replied back with.putting a "hi performance exhuast system on it".uuhh fart tip.just an expensive one.yes i have a apexi n1 im running the v8 through.but i can admit that it is nothing more than expensize fart can.then throwing spirit r or rz badges on the 7.yet they make fun of integra's or crx's throwing a SiR type R sticker on it.get witht he program ppl.rotary shops are some the smartest ppl alive though.cuz they know rotards will keep bringing an engine back every 6 months to get it rebuilt for 3500 dollars.plus paying for a turbo tkit hat is 2000 dollars more just cuz it is labeled rx7.

RZRX7TT

man dropping any engine that isnt rotary is the stupidist thing you can do, why the hell would you do that, first of all your transfoming the rx7 to something other than the rx7, the rx7 isnt just known for its shape its known as the rx7 because of the heart and that heart is the WANKEL ROTARY, please stop ruining this beautiful ride and especially a third gen with a piston engine in it, dam one thing is for sure i sure the hell wont ever see it and i dont care to, because its stupid end of my post.

artguy

personally...Id rather just get a zo6 and modify that. but that is my opinion. you guys talk about the hassle of the rotary engine..yet you are going thru a much bigger hassle to put in an Lt1...Jlab you get yours working yet? talk about a two year hassle...granted it will be worth every penny and drop of sweat Im sure.

once they are done they will be fantastic machines...look great...perform great...sound great...but to say you are doing it to avoid a hassle that rebuilding a rotary brings is sorta silly...considering what you all are going thru right now. I cant imagine the difficulties in locating and fabricating all those parts. wow.

the only people that need to be happy with what you do with your car is you. right?

I got harassed by an idiot in the west coast forum that said I spent 20 grand and all I got is upgraded twins...but that is exactly the car I wanted...and now I have it...hassles or not.

I get questioned why I went with the m2 set when I could have gone single....yet many people do not seem to realize that all depends on what you want out of the car.

I want quick fun...I got what I set out for...I dont have time to build an lt1 or the patience and care to do it right...instead I work with what I have. To those that do have the time and bucks..as long as you enjoy it then that is all that matters.


j

PS...those power numbers for the v8 are incredibly impressive...I cant even imagine that much torque down low in an rx7....yer gonna need a LOT of rubber...but man what fun!!

I bet even the naysayers would kill for a ride in labs v8 when it is done...

dclin

iTrader: (4)

I think the reason for all the time that Jim has into his project is 1) he can't stop changing his freaking mind (how many guys do you know that has had three different sleek light kits over a period where his car was not even running? ) and 2) he has been at the mercy of custom parts vendors (I kinda know how that it is, and man, do I have a couple of stories to tell of my own experiences).

I was actually quite surprised on how quickly twint78 got his to this point. I took him for another 'talker' not too long ago (and it was only a couple months ago he was talking about doing a 20B, last I heard).

I think if one was to have gone the simpler route (meaning no crazy engine mod work), there really would not have been too much involved as far as fabrication as that pretty much everthing is included in the 'Granny' kit. Anyways, I know I've gone thru as much with my single (et al) as probably compared to a simple V8 swap....

dclin

iTrader: (4)

Don't open anymore threads titled 'V8'/etc, and you'll be ok.

RotaryWhat?

iTrader: (1)

....just one: How much of that torque/horsepower is actually usable? I'm sure having an extra 250 lb-ft of avg torque is great for bragging rights, but it just seems to me that it's a bit overkill for our cars. I mean, what's the limit as to when all that extra power doesn't make the 7 any faster?

BTW, I don't agree with what you V8 guys are doing, but I can definitely understand why and can respect it. Keep posting....if nothing else, it's entertaining to read these threads

jimlab

And don't forget 3) I rarely bothered to do any work on it in the last three years.

The biggest progress I've made in recent history (besides the engine, I guess) was getting it painted this summer. I'm pushing hard on mine now, though, and with everyone cooperating (yeah, right), it might be running in February/March, and ready for April/May when the sun comes back out. I'll be putting around $10k more into it in the next month or two. Time to wrap it up and drive it, I'm tired of looking at it.

And artguy... I already have a Z06.

artguy

jim....I know.

yer machines are the envy of the forums.

get that thing going so people will shut up already.


j

LT1-7

First of all, that is the longest sentence I've ever read. Learn to use a period.

It's funny how people say I'm doing a dumb thing and this is the stupidest thing you can do, even refuse to see the end results. The fact is you clicked on my post knowing there was going to be a V8 conversion inside. That itself says you have interest in V8 convesions weather you admit to it or not.


My conversion would have been more than done by now if I would have just dropped a stock LT1 in the first place. I was planning on dropping in a built 396ci but my car has been for so long now, I just want to get it up and running

I really don't see the hassle I'm going through. Trust me, if I would have dropped another rotary engine in, it would have taken me just as long. As you can see, I'm not going to just throw a rebuilt stock rotary in. It would have been a fully built one in which case it would have taken me just as long to redo allot of things. I don't see it as a hassle, just something I like to do right the frist time

You know how every time you step on your gas peddle and it takes awhile to get the actual pull back? Yes, that's called turbo lag No, my engine won't have that. No, not all of the extra 250lbs of torque will be usable all of the time but having more is better than not having enough, I think everyone can agree on that. And even with that much more power, I doubt you could spin the tires going say 100mph. So is it usable? Very

LT1-7

How about if I do this conversion and have a moped at the same time? Since you are so important I would really like to know how much respect you would give me. How about a scale from 1-10. Oh boy, let it be up there with the 9's and 10's!! I don't know what I'd do if you didn't repspect me



Funny you should say that. RE-Amemiya has a kit to convert to Corvette tail lights, so don't think japanese tuners are as close minded as you obviously are

LUV94RX7

iTrader: (3)

I don’t understand why the people that put V8s into non-V8 cars keep wasting their time responding to people that don’t like the idea. Who cares what they think. You will never change their minds. To me the V8 guys are the HOT RODDERS of this generation. I love hot rods.

Ken

dclin

iTrader: (4)

*edit again* Ken - Because it's fun to make them look stupid? But then again, it's really them doing that to themselves. Until someone comes along and gives a real, legitimate reason why one should not put something other then a rotary into a 7 (and please, no more of of this 'soul of the car' crap, makes me puke), I'll be fine with such a conversion.

LUV94RX7

iTrader: (3)

I like hot rods. I had a couple of the in the 60s. I guess the one that I liked the best was a "40 Ford convert with a Chev V8, Corvette Honduas red with louvered hood, chrome wheels, roll and pleated interior. No one back then made fun of me. Hot rodders were loved back then. It just is another example of America going down the tubes. People that don't like hot rods are idiots in my book. Is my car a hot rod?

Ken, 58 years young
'94 white, pep, red leather,
mods: Hayes/KDR street port & polished,
3mm Hurley racing seals,
upgraded coolant seals,
Power FC ecu, Commander, Datalogit,
XS T04e single turbo kit,
GReddy SMIC (400+cu.in.),
Aquamist 2s water injection kit,
Pettit ss resonated MP,
Pettit ss cat-back,
RP Racing fuel pump,
1600cc injectors,
Profec B(16&22psi),
3-Bar Map Sensor,
Centerforce clutch,
Racelogic Traction Control,
Under pulley kit (no air pump),
Pettit short shifter kit,
LaBreck's bushings,
Evans Coolant
http:///luv94rx7.html

jspecracer7

Wow, you're a complete idiot. PLEASE complete a sentence before bashing someone.

RedTT, I applaude your drive to be "different", especially in the face of MANY rx-7 owners that couldn't tell you what a "wastegate" looks like, or how it operates. Good Luck with the project and Keep us updated!

LT1-7

I had a friend come over today that builds race cars and he might have have changed my mind on going NA. He was very suprised at how much room I have in the frotn of my engine and even the side. He basiclly asked me why I just don't go turbo. I really didn't ant to go turbo to keep the weight down but now I just might. Here are some pics I'll be refering to when/if I go turbo. One big turbo in front of the engine, nice and simple. Now I have to figure out what I'm going to do with my stroker kit which is suppose to give me over 11:1 compression. Hey Jim, do JE have pistions that would work with my crank and rods to give a lower compression?

Felix Wankel

Oh. My. God.