Remember you are calculating air/flow for HP at the flywheel .....

 

And now to take it back off track :

Ok, now for a 20b, we'll stick with stock ports just to make it easy... please correct this formula if it is wrong

120 * .70 * 8000 * 1/1728 = ~389

The part I don't know about the 3rotor is the displacement/rev (D_R).... I'm pretty sure its not still 1, but is it 1.5 or 1.33 or what? How would you figure this out?

Also, assuming you have a good street port (I know that this is a VERY vague statement), would it be enough to make the VE at least = with a boinger? or could it actually surpass the VE of the boinger with the same displacement?

Thanks,
Nick









Gene [/B][/QUOTE]

 

Good thing you posted the graph.
I would also like to point out (and stress) that the 424 number was taken at a peculiar peak at the very end of the run.&nbsp "Peak" power is exactly that - you could get wildly fluctuating dyno run and hit a peak power number that is not truly representative of a real run.&nbsp You could argue that the slope of the graph could hit the peak, but this is a what-if question...

Not to take anything from the achievement - it is a solid 400hp to the wheels run, which is not an easy feat by any standard to do on a 13B.


-Ted

 

Yeah, it does reach 424 after a slight bounce at the end, (i wish that run was an RPM graph instead of a mph graph...) He does hit 400 rwhp 10mph earlier (whatever RPM that equates too, I'm not sure... I'd do the math, but I'm too tired ) So, it certainly can be done.

BTW, I'm sure you know this ted, but most people probably dont.... his air to water setup used the stock top mount intercooler with a water resevoir JB welded to the sides and a Home Depot pump and rigged heat exchanger up front... BDC has a lot of ideas

 

I'll have to agree with you on that also!

crispeed

 

Come on Ted! Give us an answer! I have answered the A/R many times for Rotorheads, Honda bubbas, Stupra dudes and just about anybody else who wants to know. What is A/R and how is it measured? Of course you are just gonna quote something from Porky Smell's book but please enlighten us lowly people with no knowledge?

 

I think we should probably stick to method number one, and use 1 for the displacement/RPM. A very good street port probably won't increase the VE by a huge amount, (perhaps to .8 ?). That's close to a boinger whih is typically .85 for modern engines.

A big bridge or peripheral port will be higher...close to 1 (recall reading this in a few SAE papers a while back). Again, the street port figure is a SWAG a I have yet to see real data.

Gene

 

I remember reading a while ago that BP & PP 13Bs would hit almost 100% or over 100% with the right intake. This has to do with the intake pulses..


A street port is on par with a boinger..


The reason i have heard the rotary is down on power is because so much exhaust heat is lost through the peri. exhaust port.


The new renisis motor corrects this problem.


-Zach

 

Okay, I did some more complex calculations to figure out corrected flows and max boost per thousand RPMs for 4 turbos on a stock (non-ported) 13B using Turbonetics compressor maps. These are only estimates, but they seem to agree fairly well with other's data.

Below are the results (might want to copy/paste into Excel or something):

Boost PSI/RPM
Turbo 2000 3000 4000 5000 6000 7000 8000 8500
60-1 1 5 14 17 22 23 22 22

62-1 0.5 6 14 17 22 23 23 24

T04E 57 1 7 14 23 25 22 17 15

T04E 60 0.5 5 13 17 23.5 23 20 19

Note how the boost rolls of after 6-7K RPMs for the T04 turbos. This is a function of compressor efficiency and stock porting.

If you like, I can run these numbers for street ported motors, making a guestimate of VE.

Regards,

Gene
www.purplemantis.com

 

A good a "very" good street port should approach 92%-98% @ tq peak.
VE% is related to many different components in the system though.

 

Compressor efficiency should be the same unless you are significantly raising boost at 8000-8500?

What VE% did you plot. What stock ports are they. The T2 ports are extremely small in comparison to REW/RE ports.

I believe with stock FD ports the VE% @ tq peak is around 85% with a larger exhaust housing turbo, and other supporting mods. This is why the "standard" street port for an FD engine can get away with "cleaned up" ports, IMO.

I wish RICE RACING would get on here and post some real VE info .

 

BDC is using my old turbo, I sold it to him about 3 years back. It's a 60-1 hi-fi compressor, which flows about 10% less than a regular 60-1. So I'd say 400 hp at the wheel shouldn't be a problem with a ported 13B at all, even with air-air ic.

The response of the turbo was pretty quick too, equals or even better than the spool of my non-sequential turbos on the 3rd gen right now. I remember it making lots of power even at 8 psi (~300 hp to the wheels), so it's definitely a good street turbo, a good candidate if you're looking for something to replace your failing stock twins.

Fred Jin
93 silver touring
80 SA Bridgeport

 

many people probably wont beleive this... but i am goint to have a little over 500hp... w/ a 60-1... YES a 60-1 when the car is finished... i'll stick some pics on here and also some dyno charts so you guys don't think i am full of crap.... just keep an eye out for my name... the car should be done some time i'm hopping in july...

 

the problem wasnt making 400 rwhp.....it was doing it at around 15 psi

 

and still no one has T61 info or experience.....

 

Lots of talk, no proof - it would've looked better if you waited till you get your proof then posted this.



-Ted

 

I wish I had dyno plots of my 60-1 on my FC ported engine. I was probably close to 400rwhp at 15psi of boost at the very end of my powerband (8000rpm).

I'd have to agree with Ted that it'll be the peak power.

However, it CAN be done, but it's not easy.

BDC, ran higher boost and a cooler day (compared to mine).
He has a very different engine port from my engine as well.

To answer your recent question, sorry, I don't have info on a T61 set-up. I'm interested in the ANSWER to THAT question maybe 20 posts later.

J

 

i may just have to guinea pig it and try out the T61....

 

Specs:

Ambient temp: 22 deg C
Intercooler Effeciency: 85%
Compressor Eff: 70%
PR - 2.034

"Good" Street port.
313 TQ @ 6100 (90% VE)
424 BHP @ 7800 (82% VE)

Same Port larger exhaust housing.
313 TQ @ 6350
441 BHP @ 8100

Great Street port, large exhaust housing.
320 TQ @ 7600
491 BHP @ 8800

Hard to accomplish but possible. The same could be made on a t-61 without breaking a sweat on that turbo. In fact the compressor eff. would be about 73%.

 

yes.....but should Nic go with the 1.00 exhaust or the 1.15...

i know the 1.15 will work fine....but im afraid it wont spool quick enough for my liking

1.00 spool faster....but will it die on the top??

SOMEONE who knows from experience tell me that it will or will not die with the 1.00....

info PLEASE.....or im just going to have to stick my neck out and try it out and id rather not do that

 

The difference between spool will be noticeable. The difference between top-end power will be less noticeable. On a dyno it will definately be there, but it will be hard to feel.

Take into account your porting. How large is it? It may be with a very large street port, your engine itself will not want to make power at lower-mid rpm ranges anyways, even if boost is present.

It's all about what you want. Power increase from larger housing will happen, but it can be VERY marginal with a "standard" street port. Where a huge street port would take full advantage.

-Brian

 

The VE of a street ported rotary far surpasses the VE of a piston engine, the VE of a BP or PP engine is well over 100% usual measures in the region of 115 to 120% depending on a few variables (timing specific/manifold length and air speed)

Where the rotary looses out is in the BSFC especially if the porting is ****, IE near std, this is why tend to make a little less power in std or badly ported form, however this is changed by using higher compression, and getting higher dynamic compression due to the far better VE of "street ported & upwards" porting. The BSFC greatly improves at peak power and peak torque in heavily ported engines to the point of almost being the same as some piston engines, did you know that PP engines have about 15% better BSFC than a side ported engine at WOT and mid to high revs? Realy good side ports (street ports) display similar characteristics, that is why sometimes it is hard for people to believe the power some people make at lower boost on much smaller turbos (compressors)

400rwhp @ 15 psi is not a problem with higher peak engine speeds that street porting gives you and with a properly toleranced "built" engine, you will achieve this at std temp/pressure day at sea level with a charge temp of 45 deg C, if you can make peak power near 7800rpm to 8000rpm this power level will follow. It is the minimum power you will make with a good header, not a cast POS, decent IC, well built and tuned T2 engine.

My T2 street port makes 500bhp on 1 bar, that is well over 400rwhp in your numbers.

 

Actually many modern boingers easily surpass 100% VE! Notice that new cars have some really bizarre intake manifold setups with two or three (or infinite!) runner lengths that are swtiched at various RPM. That's a big part of it!