joeylyrech

iTrader: (11)

OK Ted they are running injection now on they race cars(modified class)but i was talking about before around 10.00 years ago when everybody in the USA was running EMS they were running this kind of setup and like i said running way faster than anybody(aparently a good setup for a fun,fast budget race car)Now on the streets a lot of people if usings this stuff(went down a couple of months ago and 4 out of 10 rotaries were running this setup) cause its cheap and easy to tune and it work the same way as a regular turbo setup,i do know that you dont have the control and tunning abilities like on a EMS setup but my point its that it works and its not as bad like some people think

RETed

Sure, it works.
Their formula was super light chassis with decent power equals fast times.
You didn't need that extra last 10%, cause there were only a handful that were consistent back then.

Yes, "cheap" and "easy" is right.

My point was no one said it DOESN'T work.
You need to watch out what people are saying, because the thread can get twisted.
My point is that EFI is advantageous over carburation.
I never said carburation would not work, nor did I call it crap.
EFI is a lot more involved than a "screwdriver and a bunch of jets".
Mr. RotaryShack just reinforced my argument - not refute it.
He took it personally cause I don't like carbs - which wasn't my point.


-Ted

680RWHP12A

ted, my car has had fuel injection on for years now and makes over 700rwhp, but thats not the topic here is it?

well, carlos gonzales uses a what you call "archic distributor" to power his second gen into the seven second range, and he was competitive in his class(modified)

link
http://www.nhrasportcompact.com/2006..._Gonzalez.html

oh and i searched the good guy/bad guy didnt find anything bad

680RWHP12A

actually, they drive quite nice when properly tuned.. they drive like a carbed n/a car off boost and they haul *** when the turbo spools up

like joeylyrech mentioned its all about getting the fpr dialed in.. its simple

RETed

Yeah, I guess you're right on that one.
It's all buried in the 1st gen section...

https://www.rx7club.com/1st-generation-specific-1979-1985-18/rotaryshack-com-mazdaracing-com-122944/
https://www.rx7club.com/1st-generation-specific-1979-1985-18/rotary-shack-149065/
https://www.rx7club.com/1st-generation-specific-1979-1985-18/latest-rotaryshack-13bturbo-swap-80rx7-274305/page5/


-Ted

680RWHP12A

bravo! well said! cheap fast and reliable, it dosnt get much better than that!
i never said blowthrough was better than efi, its just alot more bang for your buck

anybody can dump thousands of dollars on a nice efi system, then fly steve kahn out to dyno tune it, but you dont have to...if you dont want to

racerlinkfc

i've seen many blow through carb setups and the nicest i've ever seen have come from the rotaryshack . you haters can talk all the crap you want but those first gens are freaking fast !

ZAN_TUNING

iTrader: (1)

ehhh, i drove mine every day =) bridgeported t70 blow-thru... a/c was nice too. sold that engine tho and now run haltech for the 40+ psi territory

ZAN_TUNING

iTrader: (1)

yep, i was using a boost referenced power valve on both the primary and secondary side which was sooooo great for the street! afr's were in the low 14's off boost and high 10's to low 11's under full boost with a nice taper leading down to those. held flat till i let off every time.

i actually still get more questions about that setup than the new one. the only thing i didn't like was how close the turbine was to the rear bowl. i had a blanket on it and all but it still bothered me. if i had kept that setup i would have built a manifold to push the turbo a little farther up oh and i DEFINITELY would have added a block of cheese or two

680RWHP12A

i thought that was you.. whattt up cheese

im glad you got the holley setup running good, but for 30+++ psi a carby wont do

Aaron Cake

iTrader: (1)

Thread cleaned up. Please keep it clean people. Just because someone disagrees with the way you do things, does not mean that it's alright to insult them.

ZAN_TUNING

iTrader: (1)

hell yea, i maxed out at 28psi and couldn't get anymore fuel without stepping up to an 850. ah well, it was fun times!!!!!

i gotta call you soon man, we gotta catch up!

Hyper4mance2k

iTrader: (40)

FYI a properly tuned carb application will allwyas make more peak horsepower than any EFI system. This is due to the huge temprature drop when the fuel atomises. This same thing doesn't happen in an EFI setup so the intake temps are allways higher. The biggest bennifit to EFI is that you can get a broader power band and make more power over a larger RPM range then you can with a carb.

Evil Aviator

I'm sorry to say that's just an old wive's tale. An EFI system could easily incorporate a venturi if desired. The difference is that a carburetor needs a venturi, while it is optional with fuel injection. Since most fuel injection systems do not include a venturi, I think it is obvious that the temperature drop at the throat isn't worth the accompanying restriction. However, you are welcome to install a venturi on your EFI intake if it makes you feel better.

RETed

I wasn't going to say anything, but...

To claim a carburator would atomize fuel better than a high pressure fuel injection system is just...STUPID.
Please folks, I think you should shut your mouth if you're going to claim things that go against the laws of physics.


-Ted

Hyper4mance2k

iTrader: (40)

We still wish you wouldn't have said anything. No one said that it could atomize fuel better than EFI. It simply does it differently. Go back to school. When the pressure drops across the choke and the venturi effect takes place and the fuel atomizes and pulles into the carb it makes a drastic drop in temprature. Like, a below ambiant drop in temp... This spring on a humid night at about 50* ambiant I would have ice on my upper intake manifold after a few fun runs. Oh, and I had no intercooler. Just a 45 DCOE weber, a S5 turbo, and a 13B at 15psi.

sharingan 19

iTrader: (16)

this is interesting stuff.....I'm going to get my popcorn.

Maybe when I get back there will be dyno sheets and videos too

RETed

Let's see...

It sounds like you were saying...

The (supposed) increase in (peak) horsepower is due to the "huge temperature drop" from the way the carburator ATOMIZES the fuel.
This implies the fuel atomization is superior due to the carburator design.
Which implies that the fuel atomization is either *more* or *better*.

We can basically throw out "more", since we're talking AFR's here.
Unless we're comparing huge differences in air flow, we can ignore the "more".

Now, that leaves us with "better"...
How do you get "better"?
Since we are talking about atomization of a liquid, "better" atomization would normally imply *finer* atomization.
So this comes down to a matter of (jet) orifice size and FUEL PRESSURE.

WHAT FUEL PRESSURES WOULD A NORMAL CARBURATOR SEE?
WHAT FUEL PRESSURES WOULD A FUEL INJECTOR SEE?

Are you going to argue that the carb jets are smaller than the fuel injector orifice?


I guess this phenomenon doesn't happen with fuel injection then?

Oh, yeah, you're right...I am going back to school, but it's not for this kinda stuff.
I've had enough math and physics, and I've decided to take a different path in my life.

Oh, BY THE WAY, physics folks call this the Bernoulli Principle.


Are you talking about a 50F ambient or a 50C ambient?
There's not many places that would see 50C of ambient, so I'm going to assume you're talking about 50F.
Since "ice" is just frozen water, and assuming about normal atmospheric temperatures, water should freeze at 32F.
So your carb gave you an 18F temp drop?

Lesse...
15psi of turbo pressure...no intercooler...
This engine still in one piece?
You running something other than pump grade gasoline?
Unless you're running methanol or something similar, I call you BULLSHIT.




-Ted

Evil Aviator

I think he was trying to say that the temperature drop in the venturi cools the air, increasing density, and therefore increasing engine performance without respect to atomization. It doesn't actually do that, but I think that was his premise.

... And some people call it a restriction, but I call it a venturi, umm humm.

It's just a phenonenom in which the humidity comes out of the air and freezes. This mostly happens under part-throttle operation in high humidity conditions. If you are saving these threads to your hard drive, you can park the "omg my intake has frost!" posts in the same folder with the "omg my turbo is red hot!" and "omg there are flames shooting out my rotary engine exhaust!" posts.

680RWHP12A

i will respond to this in detail tomorrow but ponder this...

when a fuel atomizes(or vaporizes ) with air what does it do? it gets cold.. so... the carb is much farther away from the block than the the injector in the block right? so the carb has a much larger distance from the motor than the efi(fuel injetor) to take advantage of the vaporazation mixing with air) super cooling

bottom line is a carburated long manifold will super cool the intake charge wayyyyy more than a efi car shoving hot air into the block with a fine fuel atomazation in the engine block

racerlinkfc

so thats why the carb stays cold ! this is a fun read very interesting !

Aaron Cake

iTrader: (1)

FWIW, I've witnessed the frosty carburetor first hand. Half bridge turbo 12A, blow through Weber, stock S4 turbo, no intercooler. After a few runs the hood could be opened quickly to see the frost melting off the carb outlet...Kind of neat...

sharingan 19

iTrader: (16)

this is sounding more and more like a fun little back yard project

Hyper4mance2k

iTrader: (40)

Wow first hand experiance from more than just me. It's people like you who can't read, and who take what people origionaly type and twist it into their own garbage that lead into internet parroted knowledge. AGAIN, for the reading impared, I said nothing about better atomization, but rather I was refering to the temprature drop across the choke/venturi/restriction that will allow for a denser cooler intake charge that will yeild more PEAK power. Dude just do some damn research and stop being a dick.

RETed

Learn some &(#%)(&# English then, cause you're not making your point clear enough.

Your implication is that on carbs are able to do this...
When in fact, fuel injection does the same thing.
You conveniently forgot to point out that fact, and others might be misled by your comments.

You're still harping on the fact that your LATENT HEAT phenomenon is restricted to carbs?
It's not.
"Allow for denser cooler intake charge"?
Denser than what?
Cooler than what?
Fuel injection???
You gotta be kidding me...

Internet parroted knowledge?
Dude, look up any physics textbook.
It's all in there.
It might keep you from looking stupid the next time.
You scared I might just know more than you do?
Scary isn't it...


-Ted