Hey, first post...gonna buy a project FD here soon and trying to get an idea of what I am looking at. (coming from owning 3 240SXs)

So my goal right from the start is to make around 600whp, i want power. So I have been researching on my own and have come up with a few turbos that could possibly do this. 500R, GT40R, GT42R, and the T51 Kai. (I dislike Greddy turbos personally lol)

I am going to be having a large streetport and am ok with some noticeable lag, not trying to defy physics here, but obviously the most responsive turbo that can reach that goal would be best, which is where I need some direction.

On top of all that, it would be awesome if I could reach 600whp with 91 octane, but that may be pushing my luck...never the less, I would at least like to hit as close as I can with 91 and I will more than likely have a race gas option on my tuning...

Thanks for the help.

 

GT40R

Mine spools early and hits hard. This is on a full bridgeport though. Nevermind, I just saw that you said you want to do it on pump gas 91. Agree with Ted.

 

Not going to happen...

Either you're going to be boosting past the limits of pump gas, or lag is going to be significant.


-Ted

 

So lets say its possible with 116 or something, thats fine...what would the be limits that 91 gets me...?

I am also contemplating going with a half-bridgeport...

 

have you considered meth or water injction?

 

42r... Though you're not going to do it on 91 alone.

 

You can just buy my setup and have an instant 735rwhp!

https://www.rx7club.com/showthread.php?t=708491

 

Haha, thats a baller setup man but i need the car first Plus I kinda want to build it all myself...a learning experience!

My plan is to have a race gas map and a 91oct map, this is going to be my second car for weekends and such so I don't want it to DEPEND on race gas, water, or alky. The injections are just something that complicate what I want, which is, at its base, relatively simple.

From what I've seen, the GT40R is pretty good, is the 42 version just a little more lag for a little more power?

What kinda power am I looking at for a 91oct setup with one of said turbos you think? 450whp~? From what I noticed with these turbos usually around 1 bar is max on 91...would this be correct? It would be nice to hit at least 500whp, but I can try to be realistic

 

Only way you will hit 500rwhp is with water/meth injection

 

e85?

 

400 rwhp on 91 octane will most likely be the safe limit. With methanol injection, you can probably push that to 500 rwhp.

You have to remember a healthy 400 rwhp in an FD is enough to trap 125ish mph in the quarter, these aren't heavy pigs like the supra, mustang etc

 

welcome to rotary land. do it right and you will never regret your decision.

600 is at the top of the hp range before you need to get into lots of esoteric engine internal stuff mostly relating to crank, er eliptical shaft, flex and the engine plates moving around. so your 600 is a fair top target assuming you do it right.

i really respect your wish to do it yourself...

a couple of considerations.

the rotary requires more airflow than a piston engine. generally a piston engine will produce around 10 hp per pound-minute of airflow, i e a 65 lb/minute turbo will produce 650 hp. a rotary is less efficient in re to flow.

a 65 lb/minute turbo on a rotary requires the following calculation.

65 X 10 = 650 / 1.3 = 500 max rear wheel rotary hp.

or

65 X 14.471 = 941 CFM/ 1.92 = 490.

so when you look at turbos use the above calculations and you will be in the ballpark for MAX rotary rwhp.

an 80 lb/min turbo will get you around 615 for instance.

this doesn't mean rotaries are at a disadvantage... you just set it up to flow more air.

the other item is fuel.

given your fuel choice your street hp limit will be fuel not airflow. the engine can take just so combustion chamber pressure before knock. you mention 91 octane. can you not run 93 in your area? regardless, it makes little sense to me to have a fuel limited 400 rwhp on the street and 600 on the dyno when you can have 600 on the street.

the fix is methanol injection. it is the perfect solution to 91-93 octane pump fuel. and it is evolving faster than the tach spins on a 600 rwhp rotary.

i have just installed the newest architecture. the FJO AI system functions as an additional fuel system it employs fuel injectors and is guided off a X Y 256 cell grid which has rpm and boost controlling influence.

here's the grid w my % deliverability (1400 CC Min max) settings.


here's a pic of how the two injectors install...


the pump


i suggest your revisit your research re AI ( see the AI section on this board) as you can have your cake and eat it too. while i appreciate your desire to keep things simple there is no simple format to build a 600 hp FD. you do need to employ certain systems.

BTW, my goal is also 600 rwhp. my turbo solution is two 44 lb/min turbos. i have 10,000 miles on the setup that i built myself and think i am a dyno session or two away from my goal. i think i can do it at under 25 psi boost. maybe yes. maybe no.



good luck and welcome to the club. build it right and you'll build it once.

howard coleman

 

+ 2

 

nutz!

 

Thanks to all the replies, especially howards.

I have questions about meth injection, but I will save those for the correct forum. As far as availability of 93, none. I am in Colorado...all we get is 91, probably because we are a mile above sea level. But don't quote me on that. Btw, your setup looks sweet.

So assuming large street to half bridge, meth injection, and gt40r...hows that sound anyone have any experience with a similar setup?

 

Howard Coleman, nice work man. Where do you store the methanol? How long does it last before you run out? Do you have a gauge to keep an eye on the level? I've always known about methanol and its wonderful properties, just never saw it done on a rotary engine. Those injectors, how much do they flow? Thanks

 

go bigger. You would need a killer built full bridge and tuned by one of the best to get 600+. I suggest going with a 42 or atleast a 4094.

 

You guys forget I made just over 700rwhp on a street port. BP is not a must, it helps, no doubt, but not a must. I say follow what Howard has done.

 

my injectors do 700 CC/Min each. my pump setup is 850/1600. prior to the methanol i had run my pump injectors to 90% duty cycle. with the methanol they are in the high 60% duty.

i run a 4 gallon Jaz fuel cell. it is recessed to the floor of the spare tire well. it lasts quite a while as when you get to around 500 hp there are fewer opportunities to really lean on it. almost out of control. i am sure Ernie T has a few stories.

yes, i do have a red LED that lights when i get low. no problem.



there's lots (180 threads, 2511 posts) of info in the Auxiliary Injection Section.

 

Messinian7: im in breck for the winter, and im missing my car. if you want an extra hand, lmk, i have a good friend living in ft. collins so its a good excuse to visit.

and off topic...HC, what are your intake temps like with the SMIC? or have you upgraded since that pic? it seems as though every system in your car has been gone over with a fine tooth comb, as it should be. all the AI info you have presented has been great and i know will be a real help in the future.

now i just have to figure out if i want to go with AI or E85.....or both.

 

i relocated my air temp sensor before the elbow so i don't keep track of the alcohol's cooling effect from a temperature aspect. after a dyno pull, however, my UIM is very cold to the touch.

as to ICs... "have you upgraded.... from a SMIC" i consider the SMIC an upgrade from a FMIC as far as road racing. intercoolers are heavy and i want as much rear weight as possible. i am at 54%.

please don't take offense as none is intended. and thanks for the kind comments.

hc

 

You really broke 700 with a streetport!?! What were the exact specs on your 42r again?

 

600 is my goal too. I'm gonna try to do it in about a year with 1.0 500r, water/meth, and some 108 octane. Goodfellow has the same turbo, I remember him saying he thought this turbo would max at about 600hp. What do you guys think?

 

Based on the size of the compressor wheel, the 500R should crack 600 at boost levels approaching 30 psi.

 

The following paragraph is a Private Message response to me about finding the right 600 whp turbo. The author is very experienced in this area at these power levels. I had a thread like yours last spring, and I concluded that the gt4094 was the best choice if the goal is 600whp.

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A T51 is essentially a 42R, minor minor differences. I would say a good setup might be a 4094 or even the smaller 42(94)R. The issue is spool. And the larger the turbo the longer the spool. You can offset this with other things but it will never be quite as responsive as say a 35R. The 500R would be hard pressed to get you 600hpyou would have to wring the crap out of it is my guess.


Quote:
Originally Posted by III Gen X
As for the level of build, it has everything. It formerly had a t-88 on it running 30 psi and nitrous. When I bought it, I wanted something more streetable so I went with a T-61 and only ran 22psi. The car now has a new owner and he wants to hit the 600whp mark. Since the gt42r can support over 700whp, I'm guessing there is a smaller turbo that'll get the job done. I thought about the 500r, but I don't know anything about its hot side flow capabilities. Will the 500r flow enough on the exhaust side for this power level? Or should I be thinking about one of the gt40 combinations and which one. The car is street driven and owner wants both quick spool for street racing and plenty of top end to boot. He thinks the t-51r kai is where it's at, but I told him you might have other ideas. THanks!