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-   -   Rotaries with Blowers vs. Rotaries with Turbos? *PICS* (https://www.rx7club.com/rotary-car-performance-77/rotaries-blowers-vs-rotaries-turbos-%2Apics%2A-158700/)

Resource 02-16-03 08:46 PM

Rotaries with Blowers vs. Rotaries with Turbos? *PICS*
 
Most of the big horsepower rotary guys have turbo rotaries. What's the reasoning behind not going the blower route?

This guy claims to be putting down around 900rwhp in his blown FC 2 rotor. I say no way in hell. I'm not sure what's the story on this FC but he lives nearby me.

https://www.rx7club.com/forum/attach...postid=1502127

Resource 02-16-03 08:47 PM

another

https://www.rx7club.com/forum/attach...postid=1502129

KNONFS 02-17-03 03:12 PM


Originally posted by Resource
another

https://www.rx7club.com/forum/attach...postid=1502129

I don't think that's a rotary engine :(

rotarygod 02-17-03 03:24 PM

Why not? It looks like a rotary to me. He just found a way to stick a roots blower on top of the factory manifold. I don't see how you'd get 900 hp out of it though. If it were a bridgeported 3 rotor running methanol I might believe it but that looks like a 2 rotor to me. No way in Hell theres 900 rwhp out of it. Looks kind of neat though.

moespeed 02-17-03 04:53 PM

Why ask us. Why don't you ask him to show you his dyno sheet? Did he run it at the track? Where is the charger belt? Where is the Crank pulley? Do you have a pic with the blower belt on it? If he even made 700 RWHP without Nitrous, this would be an interesting Blower vs Turbo post.

CrackHeadMel 02-17-03 05:16 PM

does that think have a distributor? looks like a vacume advance pot where the CAS should be

is it a 12a or 13b? im not thamiliar with the older frontplates

rxrotary2_7 02-17-03 05:40 PM

it appears to be a 12a front cover. using a 12a front cover is very popular for mounting a 13B into a 12a chasis, but why its used here still remails a mystery to me from 2 pics... :confused:

Evil Aviator 02-17-03 06:18 PM

Re: Rotaries with Blowers vs. Rotaries with Turbos? *PICS*
 

Originally posted by Resource
What's the reasoning behind not going the blower route?
1) Blowers are thermally inefficient (in newbie terms, they are the opposite of a cold air intake). For example, most of the common aftermarket turbos have a little over 70% efficiency, while a Roots blower is only about 50% efficient. Heat costs horsepower.
2) Blowers have their biggest advantage at low rpm's, while rotary engines produce most of their power at high rpm's like turbochargers. How anybody thinks that rotary engines and blowers perform well together is beyond me.
3) Turning the blower belt requires engine horsepower.
4) A turbocharger's turbine wheel can soak up to 70% of the engine noise, making a turbocharged rotary engine streetable while a blown engine of the same horsepower will be too loud.
5) With modern ballbearing turbos and sequential turbos, the low-end power issue is not very significant like is was back in 1960.

Advantages of the blower:
1) Looks cool
2) Sounds cool

Resource 02-17-03 06:40 PM

Like I said, I have no more info on this car that what I've said already. He hasn't ran it nor dynoed it. He only claims what he thinks it will do.

KNONFS 02-17-03 08:31 PM


Originally posted by KNONFS
I don't think that's a rotary engine :(
Damn it, I still don't see a rotary engine :(

CrackHeadMel 02-17-03 09:02 PM


Originally posted by KNONFS
Damn it, I still don't see a rotary engine :(
http://www.teamfc3s.org/forum/attach...&postid=100854

a. is where the cas would go, looks the same as my engine (its in the garage, i just went and looked)
b. is the OMP well looks to be blocked off in the pic, but in same location and relative same size as mine

-Jacob

rxtasy3 02-18-03 10:35 AM


I don't think that's a rotary engine
Yes it's a rotary.



He only claims what he thinks it will do.
Exactly! It's obvious it's not running yet. He figures with that size blower it should put out that much hp.



it appears to be a 12a front cover. using a 12a front cover is very popular for mounting a 13B into a 12a chasis, but why its used here still remails a mystery to me from 2 pics...
I haven't noticed any difference in the front covers between 12a and 13b. The 2nd gen 7's have 13b's in them. The use of the front cover off a 12a or pre '86 13b, is to get the front mount for swapping 2nd gen engines to first gen chassis.

rxrotary2_7 02-18-03 10:49 AM


Originally posted by rxtasy3

I haven't noticed any difference in the front covers between 12a and 13b. The 2nd gen 7's have 13b's in them. The use of the front cover off a 12a or pre '86 13b, is to get the front mount for swapping 2nd gen engines to first gen chassis.

i dont knwo if you were disagreeing with me, or confirming what i was saying... but that is exactly what i was saying.
if you look at the pic, the front cover has the mounting studs there and uses a fabed mount. ;) if it was any 2nd gen 13B in the car... there would be no need for this. unless the guy tapped a FD block in the center housing the stock MM would not be in use... causing him to use an alternative method of mounting the motor. in this case, the water pump studs would haev to be swapped out due to a difference in size, and the oilpan would most likely have to be from a 2nd gen to make up for the gap. i dont know how else to describe it, i am not good with words and explaining things. :rolleyes:

1FastT2 02-18-03 04:14 PM

That guy is going to be disappointed when it makes half of what he thinks its going to make.

Resource 02-18-03 09:11 PM


Originally posted by 1FastT2
That guy is going to be disappointed when it makes half of what he thinks its going to make.
I agree.

RX-Heven 02-18-03 11:01 PM


Originally posted by 1FastT2
That guy is going to be disappointed when it makes half of what he thinks its going to make.
No doubt. But it still looks badass

trex72 02-19-03 06:37 PM

thats my buddy charlies 2nd gen, hes out of springfield MO
its a 3rd gen ROTARY engine though.
760ish hp at 26 psi, 8.5 possible ets

Liquid Anarchy 02-19-03 06:55 PM


Originally posted by trex72
thats my buddy charlies 2nd gen, hes out of springfield MO
its a 3rd gen ROTARY engine though.
760ish hp at 26 psi, 8.5 possible ets

Actually, that's partially right...

That is most definatly Charlie's car.. here are a FEW facts. The Block is MOSTLY 3rd Gen, the front cover and oil pans are off of various 1st Gen's, and the intake manifold is comprised of a few different gen's. I even know what the blower's from... but I'm not tellin'...

He's done a lot of dyno-testing on it, but he never told me the #'s, so he won't be dissapointed @ the #'s it puts out; he knows them, and seemed VERY happy with them. About his ET's; he HASN'T ran the ¼-mile yet, he said something about this season... and Dallas... ;)

Those pictures are also kindof dated. His setup has changed a little bit, and the car runs (I've heard, seen, and cried about it) oh oh oh!!! I helped put on the blower's belt too!

protlewski 02-19-03 07:26 PM

well then get some pics, man of blower belt expertese.

RX-Heven 02-19-03 09:39 PM


Originally posted by Liquid Anarchy
I even know what the blower's from... but I'm not tellin'...
That just looks like one of those B&M or Wieand single carb under hood blowers for v-8's. That pulley does look awfully small though...

Resource 02-20-03 07:05 AM

Find out some dyno numbers for us.

moespeed 02-20-03 06:09 PM


Originally posted by RX-Heven
That just looks like one of those B&M or Wieand single carb under hood blowers for v-8's. That pulley does look awfully small though...
If you look to the left of the blue bottle with the breather you will see a cog pully that is laying in the engine compartment. Does this belong with the setup?
If that is the case, the pully on the blower will have to be changed.
Hey Resource,
Like you said you have no more info. With that reply you did let us know that the car was not dynoed.
Did he ever get it running with this blower?
Did he work out the belt assembly for the blower?

94mazdatt 02-20-03 07:29 PM

He never said he had 900hp, but someone seems to be a bit woried about a certain rx. Hey Resource youve got to beat that dane ol supra first before you go after the blown rx. Like i said before thanks for the support!!!

LTProject 02-20-03 07:35 PM


Originally posted by Resource
Find out some dyno numbers for us.

how about your HP's number x 2, or lambos x 1.5. Resource would you please go play on the stl forum SHANES waiting for you.

Resource 02-21-03 11:51 AM


Originally posted by 94mazdatt
He never said he had 900hp, but someone seems to be a bit woried about a certain rx. Hey Resource youve got to beat that dane ol supra first before you go after the blown rx. Like i said before thanks for the support!!!
You're right. I mistakenly thought that I saw 900hp somewhere. It was 800 hp that I saw. Here is the quote from Hidperf

"I'm just telling it like I hear it. The guy hooked me up with some pretty hard core rotory guys who build his engine and they're saying 700hp the way it sits and 800hp is no problem.
"

Why would I be worried about a full tubbed/stripped drag car? I have a street car. Nice comparison :confused:


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