Bomb Proof Rotary????
 

Guys, just looking for some advice on doing a Rotary build vs. piston build. I want to build a car for the SRWD class in NHRA next season. It is currently a toss up between a couple options.



FD RX7 w/13B

or

SC300 w/2JZ



I would need to make around 600-800whp be somewhat reliable as far as the motor and tranny goes. Can the 13b be built to handle this kind of HP. I would want the motor and tranny to last a season like our pistons motors currenty do. We are limited to use the engines and trans from same manufacturer as the car.



If this is even possibly who builds the best rotary motor and what type of trans would hold up to this abuse. Please list your dream motor set up and who you would have build it for reliability? I already have the turbo, EMS and misc stuff figured out if we do the RX7.

I would look to crispeed on the board. He has experience at those levels.

ErnieT is at 700+ on a 13b and Ray Wilson at PFSupercars did the motor and tuning if memory serves well.

Dave at Speed Machine built the Falken drift car.

Most here stop around 400-500 at the wheels. Myself included on those numbers. I would just be guessing to recommend those levels. A few have broken into the 600+ but they have large budgets.

13b? why not go 20b?

The rules of the class limit it to a 13B.

Weight of a SC300 has to be far more then any S2000...


I have not read the class rules but I am sure there is some car you are not thinking of that is a far better car for NHRA then a RX7 or SC300. Maybe a Volvo 240 with a Volvo Motor (5cyl or 6cyl) swap. Hell even the 4cyl can see into the mid 600whp range reliable if built properly.

Not really looking to built a Volvo. The car has to be somewhat cool considering how much money I would put into it.

Dude, Volvo 240 is about as cool as it gets... Also when people see them go fast they get a ton of attention.

Talk to RX7.com . They have been doing it for years and probably can provide you with a lot of valuable information if you are serious.

Going to have Speed Machine build the motor.


Now I am looking for a reliable transmission that can handle 700whp. What would you guys recommend.

HKS dog-box?

Lenco.

Gerico

Can we discuss the internals of this type of engine?
I've been turned away by a few big-name shops who didnt want this type of project.

What are some general ideas being used in high HP engines?
I've read a wide range on port jobs, oil delivery, stud kit, dowel pinning,etc. Even different types of bearings being used as well as beveling the rotors.

Can anyone add some input to the requirements on high HP 13b engines?
I'm only asking about the short block here.

Ya, I would like some info as well.

the only thing i've been able to understand for certain is "port work" & "stud kit".
i know seals play a big part in this also.

Hmm... wow, I feel like such a big asshole for saying this so often recently, but, perhaps if you are not shure of what to do in order to make a 13b have 600HP and last, you should not undertake such a project? I think that you would be better off with doing a piston car.

Shure, you CAN learn alot about everything, but it will take more time and reaserch to do it right than you probably think is worth it....

First, if you want a high-powered drag racer, the FD RX-7 isnt the car to go with by a longshot.

Now, an old FB would actualy make SOME sense, seeing as to how it's a LOT lighter, there's a lot more people drag racing it, and theres 100,000 thousand of them left, compared to like 9,000 registered FD's out there. :gasp:

Also, the FB has a live rear axle, which you can convert to a 9" ford rear end, as I saw some FB drag guys do. You will prabably want to use a 20B (if the rules say same manufacturer, then that's still ok!) Umm, HUGE turbo, methanol injection, dog box transmission, dry sump oil lubrication anyone? Racing beat lightened/beveled rotors, HUGE ports, studd kits, and dowel pinning, custom intake manifold, ceramic coated everything, Bill Gates' bank acount,.... god, a rotary is just such a bad choice for drag if you don't know what you're doing... no way around that. :(

so let me get this straight... your response is "If you dont know already, I'm not going to tell you"?

Well I guess we should box our ems units, turbos, engines and ship them back because we dont know what it takes to hold higher levels of power.


If I'm going to take a legit stab at building a high HP rotary... I'll be doing the following (at least):
- dowel pinning and/or studs
- seals to withstand high boost
- porting (unsure of what has been proven out side of PP)
- eshaft upgrade (?)

i mean come on, not a lot of moving parts inside :)

Ruff, pay close attention to engine tuning some aspects of rotary engines are not forgiving like piston engines. Most piston engines you can detonate them a little bit and be ok, detonate a rotary one time and it will be puking out seals.

I'm not sure how long the big boys around here can run through the season without having to do a rebuild but a first season on a rotary, I would plan ahead of time for trashing a few engines.

Seems like I was a wee bit misunderstood.

I am going to have to agree with Asterisk on the FB>FD due to weight and solid axle.:)

You can buy full race motors already prepared from some shops, so you may want to look into that. If you want to be competitive, you will need a bridgeported motor with a large turbo and probably NOS. You will also need to bulletproof most of the driveline because stock FD rear diffs and axels don't hold up well to launching.
The thing about rotaries is that the "bulletproof" is more in the tune than in the build. A factory stock engine can withstand a large amount of HP, but only with a very good tune from a veteran with the rotary. I would call Ray Wilson at PFS if you are serious.

However, if you don't know rotaries, I would suggest simply going with the 2JZ engine. They are easy to build, reliable and can be built by anyone that knows drag piston motors basically.

You don't start off drag racing a full race rotary. You have to work up to it and know the engines or you will end up crying.

I think that information is wrong... I'd need Blake to help out with what I'm trying to relay here but..

I wouldn't jump into a bridgeport to make 700+ HP. It can actually hurt the power ouput. Everything needs to work as a modular-system. For example, an engine builder wouldn't say "PP, T51R-SPL, Ceramic Seals, Studs" engine done. The PP may not work well(at at all) with the turbo.

A goal needs to be set for the car (time attach, drift, drag,etc) then looking at the internals of the engine, porting, etc - in order for the maximum power to be reached.

anyhow.... Ray Wilson will not crate a motor - he wont take the chance (we spoke about doing just that).

I didn't mean PFS crates motors, i just suggested that some shops do. My opinion is that PFS knows the cars and I suggested he call them if he wants to build a car.

"I wouldn't jump into a bridgeport to make 700+ HP. It can actually hurt the power ouput. Everything needs to work as a modular-system. For example, an engine builder wouldn't say "PP, T51R-SPL, Ceramic Seals, Studs" engine done. The PP may not work well(at at all) with the turbo."

....In the drag racing world, you will also figure out that everyone has their own opinions about what will work. Then again, I used to race crew for a very prominent name in the rotary drag racing world, so i have a very good idea of what works....some opinions are more valid than others :)

nono, i'm not even touching on opinions or who did what and where they did it.

i think my point was along the lines of the approach to building a rotary-motor that would work at least 80%+ effectively... getting all the free hp you could.

and what i mean by that is this... i think there is more to building a higher level engine than saying "bridge port, large turbo, probably nos". it very well may be your experience that led you to running XYZ in the 1/4th mile, however, if the turbo matches the engine, the fuel matches the engine output, etc etc.. the perfect storm..

oh hell n/m. we've all got our own opinions and hold them so high over most others.

look - i dont want to turn the thread into a pissing match, not at all..

what i'd like to take from this thread is other builders experience, their little secrets in making that extra 20hp - what other people have learned first hand.