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-   -   ever thought going to piston? (https://www.rx7club.com/v-8-powered-rx-7s-299/ever-thought-going-piston-569629/)

razorback 09-07-06 03:19 PM


Originally Posted by GtoRx7
One thing I really enjoy about a rotary-
- I can rebuild it in a weekend
-never have to drop my block off at a machine shop to do it right, and wait 6 months to get it back.
-Or run race gas to make good power n/a.
-Never have to drop off my head to be decked after a overheat
-Never have to drop off my valves and head to have a 5 angle valve job
- I dont have to consider what type of valve springs to use, what type of compression, rings, seats, lifters, rods, headgaskets ect.
- All this makes a rotary a vacation to work on FOR ME!

yeah, because you have to buy a completly new motor.

(missed this earlier)

Mechanic 09-07-06 07:52 PM


Originally Posted by razorback
yeah, because you have to buy a completly new motor.

(missed this earlier)

you think so? must be another one of those that blew/overheated a motor and didnt know what to do with it besides replacing it.

I know a couple of REAL life people that rebuilt overheated rotaries replacing only a coolant seal, and a few other soft seals.

i dont know about you though.

i dunno i rebuilt a crappy d15 in just about a weekend, excluding removal and installation, thats like an extra half a day if i tried hard enough.

so... i dont know what the argument is about.

must be you guys...

razorback 09-07-06 08:00 PM

im not using overheated parts in my motor ever. ive rebuild a few rotary engines, and im pretty sure using an overheated/warped motor is a big no no

Mechanic 09-07-06 08:56 PM


Originally Posted by razorback
im not using overheated parts in my motor ever. ive rebuild a few rotary engines, and im pretty sure using an overheated/warped motor is a big no no

I am glad that you know that...
does everyone on this forums have something to prove?

razorback 09-07-06 09:27 PM

only when people make claims about stuff they do not know about :)

shm21284 09-07-06 10:21 PM

3 Attachment(s)

Originally Posted by razorback
if hes running a 3 rotor then i doubt hes making over 300hp n/a

Wow are you in the dark. I made 193 REAR WHEEL HP on a t2 block with a set of headers (ditched the turbo), and a street port, stock intake, stock 9.0:1 compression rotors, stock 20 year old seals, and a haltech. All under 3000 including the 1st gen it went in. Runs solid 13's.

GTORX7 made 310 to the wheels on a mustang dyno with tuning issues. After he hammered them out, I personally felt it had 40-50 more wheel horsepower, but that's seat of the pants. Fact of the matter is, he made 310 RWHP on a mustang dyno with tuning issues (leaned out at 8000 RPM, stock fuel pump), which is more than your "doubting more than 300 hp."

Oh, just to let you know, there's plenty of horsepower still unleashed in both engines, as the 20b has a mild street port, will be opening the semi peripheral ports soon (still pump gas and good streetability, mind you), and the 13b has 9:1 compression, a stock intake manifold, and a 2.5 inch exhaust.

Here's the dynomometer graphs of both engines. The second is of a lesser quality, it was taken with a digital camera, not a scanner.

razorback 09-07-06 10:32 PM

do you really think a 3 rotor can compete with a v8 na to na powerwise?

i said 300hp, 310 is not far off. and when i said 200hp na i thought he was 2 rotor. which i believe my guess is close to your 193hp mark on your 2 rotor block.

GtoRx7 09-08-06 12:09 AM


Originally Posted by razorback
do you really think a 3 rotor can compete with a v8 na to na powerwise?

i said 300hp, 310 is not far off. and when i said 200hp na i thought he was 2 rotor. which i believe my guess is close to your 193hp mark on your 2 rotor block.

Its kinda obvious that a less VE 3.9 liter isnt going to beat a better VE 5.7 liter engine, what is your point? The 20b was well at 350rwhp last year on sideports alone, and once I finish the new setup it maybe well beyond that. And I am sure V8's will beat me, and I will be sure to beat a few more V8's. You are trying to let us know something about our rotarys that we dont already know?? Because I must have missed it.

88IntegraLS 09-08-06 02:53 AM

People with cars that don't run are the most argumentative when it comes to the V8 / rotary debate. I'm speaking from experience. :)

pinknuggit 09-08-06 11:02 AM

I don't have a comment on the v8 vs rotary thing, but I want to bring up all this time people have been spending rebuilding engines. It will only take as long as the number of parts you have to replace. You can rebuild a piston engine in a few hours if nothing is too worn out - all you will need is new bearings, rings, gaskets, and a flex hone. I'm sure it's the same for a rotary that only needs new seals. However, I know a local rotary guy who spent months building his himself because he had to find someone to press in new bearings, buy new rotors, and a bunch of small things that added up. A piston motor that needs to be bored, have a valvejob, etc can take just as long.

I know that I can rebuild a dohc 4cyl 16v in a little under 2 hours, and a pair of 2v v8 heads in a little over an hour at work taking my time... the bottom end guy (who is about 70 years old) can completely overhaul a shortblock in a matter of hours (boring, surfacing, honing, assembly, everything). These guys who are taking a whole weekend to put a H22 shortblock together must just suck at life.. lol

pinknuggit 09-08-06 11:05 AM


not for nothing, there is so much r&d in the piston history, it makes our wankel engine a thing from the past. then... we get into renesis. NOW, if i remember right, the thing doesnt have perhipheral exhaust ports. what can possible happen to the apex seals... humm.... idk.
http://www.carspin.net/forums/the-fa...problem.0.html

SupraMikesRX7 09-09-06 01:07 AM


These guys who are taking a whole weekend to put a H22 shortblock together must just suck at life.. lol
They do indeed suck.


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