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-   -   how to biuld 800 hp 13b? (https://www.rx7club.com/general-rotary-tech-support-11/how-biuld-800-hp-13b-573765/)

GUITARJUNKIE28 09-02-06 11:24 PM

350 whp is plenty to have fun with.
400-450 just feels plain nice :)

anything above that i wouldn't run on pump gas, at least not in a daily driver on california 91 octane.

Nihilanthic 09-03-06 12:29 AM

Yanno with most motors you can generally figure out what part fails when and why.

With rotaries that kind of information seems really hard to come by.

No_Rotor_RX7 09-03-06 12:55 AM

i've gotten way too used to 400 and 500 hp cars :( feels slow to me now which is why i have a turbo v8 in a little fb. i don't blame someone for wanting 800hp... but i wouldn't be dumping all my funds in to a 2 rotor. just step up to the 20b and it will be cake.

$100T2 09-03-06 09:20 AM


Originally Posted by No_Rotor_RX7
i've gotten way too used to 400 and 500 hp cars :( feels slow to me now which is why i have a turbo v8 in a little fb. i don't blame someone for wanting 800hp... but i wouldn't be dumping all my funds in to a 2 rotor. just step up to the 20b and it will be cake.

Exactly. Why strain and stress a two rotor when big power is easy to come by with either a 20B or a V-8? I'd rather have a large, comfortable motor than a small straining one.

BTW, something tells me that an 800 h.p. 3 rotor and an 800 h.p. 2 rotor will cost about the same, but the 3 rotor will make the power easier, also be far more reliable, and last longer, too.

kapono 09-04-06 08:52 AM


Originally Posted by razorback
everyone always forgets about the transmission..which is about another 7k..

and full re-build + LSD which will probably be shot to pieces with that kind of power.

GUITARJUNKIE28 09-04-06 10:47 AM


Originally Posted by Nihilanthic
Yanno with most motors you can generally figure out what part fails when and why.

With rotaries that kind of information seems really hard to come by.


nonsense. there aren't that many things that can go wrong... oil failure, pre-ignition, or detonation.

oil failure tears up the bearings, e-shaft, and sometimes irons.

pre-ignition takes care of apex seals and sometimes cracks the irons at the dowel pins

detonation does the apex seals, and can crack the irons at really high hp levels.

drama 09-04-06 11:13 AM

how to build a 800hp 13B??
 
This thread has a lot of Drama. You should just learn like the rest of us. You have to blow them to hell sometimes to figure what went wrong.To learn to build 800 hp motors not just rotarys, You have to know more than asking Stupid Questions Like the one here.

GUITARJUNKIE28 09-04-06 12:51 PM

a cheaper way to get 800 to the wheels would be to grab an ls2, stroke it out to 400 cubes and add a blower.

GtoRx7 09-04-06 01:19 PM


Originally Posted by GUITARJUNKIE28
a cheaper way to get 800 to the wheels would be to grab an ls2, stroke it out to 400 cubes and add a blower.

OR, a even cheaper way is to use two high compression hampsters, and feed them some nuclear power!! Yeah, thats at least 900 worth of hp.

GUITARJUNKIE28 09-04-06 01:50 PM

now why didn't i think of that?

Aeka GSR 09-04-06 03:26 PM


Originally Posted by GUITARJUNKIE28
a cheaper way to get 800 to the wheels would be to grab an ls2, stroke it out to 400 cubes and add a blower.

you dont even need to stroke it.
edit: whoops didnt see WHP, nevermind.

GUITARJUNKIE28 09-04-06 04:30 PM

maybe YOU don't need to stroke it, but i quite enjoy it :p:

fidelity101 09-04-06 06:56 PM


Originally Posted by GUITARJUNKIE28
a cheaper way to get 800 to the wheels would be to grab an ls2, stroke it out to 400 cubes and add a blower.

that probably could end up costing just as much

GUITARJUNKIE28 09-04-06 07:10 PM

gurantee you it'd be more reliable

Aeka GSR 09-05-06 11:52 PM


Originally Posted by GUITARJUNKIE28
maybe YOU don't need to stroke it, but i quite enjoy it :p:


well ill tell you this. I work in a sandrail shop and we got in an ls2 with a whipple blower. The thing did 840 crank hp. That was just an out of control machine, instant boost and shitloads of torque. The thing had me shittin bricks, its good I was only a passanger on that one, I would have killed myself.

That engine was nearly $30k

Nihilanthic 09-06-06 01:56 AM


Originally Posted by GUITARJUNKIE28
nonsense. there aren't that many things that can go wrong... oil failure, pre-ignition, or detonation.

oil failure tears up the bearings, e-shaft, and sometimes irons.

pre-ignition takes care of apex seals and sometimes cracks the irons at the dowel pins

detonation does the apex seals, and can crack the irons at really high hp levels.

Parts failures from something fucking up are different from simply exceeding the strength of a given part.

At least with the "piston" motors I work on, you can generally find out the given limit of parts of the rotating assembly, and the block, to either torque or rpms... and the valve train generally has its own limits to handling higher rpms and/or crazy ramp rates, etc.

So yeah, if I know at what rpms the rod bolts give out, or what torque or rpm level the rods themselves will give out, and whatnot, it helps me decide what I need to replace depending on what kind of build Im doing.


Now, what you're talking about amounts to oil starvation (which can kill any motor...) and preignition. Im talking about the limits of individual PARTS.

Yanno, such as the stock stationary gear doesnt like to go past 8,000 rpms that much, the e-shaft after a given rpm range, etc, etc... right? Same for oiling mods and clearancing parts for higher rpm use.

But what I was asking for is when does a given part in a rotary actually fail from too much torque/power? It seems to be that the only real failure items (unless you knock like a dingbat) is... the seals, and granted you dont detonate they'll last, albeit with vastly increased wear if youre going crazy with the power.

See what I mean now?

GUITARJUNKIE28 09-07-06 03:20 AM

i saw what you meant in the first place.

the rotor faces can collapse from detonation. apex seals and side seals break, etc...

if something goes wrong, you either detonated, had an oil problem, or spun it too fast. there's nothing special to the forensics of dead rotaries.

myfc3s 09-07-06 03:36 AM

Forget it kids, all you have to do is, remove the rubber hose that connects to the wastegate, and floor the living hell out of it! oh yea dont forget to put the VTEC stickers. They add 150+ more hp's. See that was easy. And if anything happens to the motor. Park it on front of "Guitarjunkies" house.

GUITARJUNKIE28 09-07-06 12:48 PM

i'll call glenn and we'll do another 12 hour pull-rebuild-install.

MaxRX7 09-07-06 03:36 PM

you need NAWWWS..... 2 bottles, the "big ones" :lol:

BigJeff 09-13-06 01:18 PM


Originally Posted by Nihilanthic
Parts failures from something fucking up are different from simply exceeding the strength of a given part.

At least with the "piston" motors I work on, you can generally find out the given limit of parts of the rotating assembly, and the block, to either torque or rpms... and the valve train generally has its own limits to handling higher rpms and/or crazy ramp rates, etc.

So yeah, if I know at what rpms the rod bolts give out, or what torque or rpm level the rods themselves will give out, and whatnot, it helps me decide what I need to replace depending on what kind of build Im doing.


Now, what you're talking about amounts to oil starvation (which can kill any motor...) and preignition. Im talking about the limits of individual PARTS.

Yanno, such as the stock stationary gear doesnt like to go past 8,000 rpms that much, the e-shaft after a given rpm range, etc, etc... right? Same for oiling mods and clearancing parts for higher rpm use.

But what I was asking for is when does a given part in a rotary actually fail from too much torque/power? It seems to be that the only real failure items (unless you knock like a dingbat) is... the seals, and granted you dont detonate they'll last, albeit with vastly increased wear if youre going crazy with the power.

See what I mean now?

That's the point, basically. There are only 3 moving parts in a 2 rotor engine, and 4 in a 3 rotor. There aren't the moving parts like rod bolts, or a valve train, or anything like that in a rotary. It's Just the rotors and E shaft.

Someone said earlier that the 13b e-shaft will start to chatter and could break at around 8.5k-9k or something like that. There's an RPM limit for you.

The rotors themselves are solid metal so it's gonna be tough to break those so that RPM limit is gonna be really high.

Basically the only things that go wrong on a rotary are things like the seals (the big weak point for high RPMs, as you noticed) and the little gasketts and other factors outside the internals of the engine. There's not much to do to them, you port the intake and exhaust, make sure the seals are strong enough for what you want to do, and go to town.

XLR8 09-14-06 08:29 AM

Do you live your life a 1/4 mile at a time.....

weston kime 12-15-09 09:35 PM

Every number is an arbitary number unless it has some relevance. So drumming up 800hp or 801hp has the same probability unless this person would like to know ROUGHLY what is intended to build an engine of that capability. Give it a break.

lastphaseofthis 12-16-09 12:14 AM

[QUOTE=BigJeff;6088364]

The rotors themselves are solid metal so it's gonna be tough to break those so that RPM limit is gonna be really high.
QUOTE]
You've been terribly missinformed. They are not solid, they are hollow. until the last few years solid billet aluminum rotors did not exist.

Dan_s_young 12-18-09 08:27 AM

They probally wouldn't have existed when this thread was made. 3 year old thread.


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