yzf-r1

iTrader: (1)

I think this is a bit of a sensitive topic for Jim because he considered going the 20B route at one time...so it's now become somewhat of a mission to prove the almighty 396 Chevy is the "superior" powerplant in all performance categories: hp, torque, weight, and reliability

most likely the 396 IS superior....superior torque at least, and possibly even lighter with some exotic bits....of course it's NA and free of all the turbo bullshit so the reliability is a slam dunk....if your 3 rotor engine pops a seal, you either fix it yourself or tow it to Cam's shop

with that said, it amazes me what turbocharging can do to to "wake up" a relatively mild powerplant....plus the uniqueness of a three rotor engine

anyway....good luck with the conversion and keep us posted

rx7raca

yzf-r1

iTrader: (1)

I should have mentioned it's not fair to compare an NA to FA induction engine anyway, but I don't know where you would hang the turbo paraphernaila in an FD engine bay with a 396 sitting in there

felix_is_alive

well dont know much about all that crap but once you HEAR a 3rotor rev ...........there is just no better sound than that

ech

David,

Have you considered traction control? I don't know if RaceLogic will work with the 3-rotor or not.

jimlab

At 12+ psi.

I've heard a lot of things about the Banzai... I've just never seen any of them backed up with a real dyno sheet or any independent reports. All I see is a lot of "Cam says...". Of course "Cam says". He's trying to sell the conversion.

You couldn't be more wrong if you tried, Mark. This has nothing whatsoever to do with my engine. I obviously had more than enough money to build whatever I wanted, including a 1,200+ RWHP dyno queen as useless for real world driving as the 600 RWHP 20B mentioned previously, and yet I built a naturally aspirated pump gas small block that will end up somewhere around 500-550 RWHP. Something to think about.

You might say I'm more interested in "truth in advertising" or stopping the spreading of misinformation. I've seen enough "1,000 horsepower 20B" threads started to last me a lifetime, but people seem to believe it's as easy as bolting on a few parts, and they got that belief from reading other threads full of the same misinformation about the 20B.

John Pham (LT1-7) found space for a couple turbos...

Fatman0203

Jim I think he was just kidding around.

MichaelFregoe

iTrader: (1)

How long is the car going to be there for the conversion?

RotorMotor

iTrader: (5)

Train A leaves the station at 10AM. jim leaves the station at 10AM as well. jim stops train after after an hour to polish engine internals. Whos train even reaches the station?

yzf-r1

iTrader: (1)

posted by jimlab
[B]I obviously had more than enough money to build whatever I wanted, including a 1,200+ RWHP dyno queen as useless for real world driving as the 600 RWHP 20B mentioned previously, and yet I built a naturally aspirated pump gas small block that will end up somewhere around 500-550 RWHP. Something to think about.[/I]

those figures are de-rated a little from what I saw on your thread awhile ago, but granted I haven't been following it lately

anyway, 600 rwhp is "useless" and 550 is "user friendly" now? c'mon, let's admit this is all about "mine is bigger than yours"...."real world" driving doesn't have much to do with it....I guess you have to ask yourself what is the motivation for buidling any overpowered street car....it certainly isn't about becoming a better driver at the track or improved daily transportation

FCdemon

I do have a better idea..

SSR Professor SP1 in 18x9 and 18x10

http://image.www.rakuten.co.jp/car-wheel/img1063850458.jpeg

http://image.www.rakuten.co.jp/car-wheel/img1063850450.jpeg

http://image.www.rakuten.co.jp/car-wheel/img1063850830.jpeg

jimlab

The cam currently in my engine would have been good for ~680 horsepower on pump gas after tuning according to Brian, owner of B&B. However, it's not a street cam, which is what I specifically asked for (not Brian's fault, more of Mark Montalvo's doing). The duration at 0.050" is 260/266 while the advertised duration is 290/296, so it has very aggressive ramps and very high lift (0.688") which would be very hard on the valvetrain in a street car.

I had a new cam ground by Comp Cams with 242/248 @ 0.050" duration and 0.615" lift that will drop my peak horsepower to about 640 while picking up even more midrange power and gaining about 4 lbs. of vacuum at idle. Therefore RWHP should be somewhere in the 500-550 range.

You're only looking at peak numbers, not power curves.

An engine that makes only 195 RWHP horsepower to ~4,000 rpm and then shoots to 600+ over the next 2,000 rpm is not street friendly. He even admitted he has no chance of traction. My power curve is very broad and linear, by comparison. Real world driving has everything to do with it, especially the huge difference in low end power.

If this were all about "mine is bigger than yours", I'd be adding the 300+ horsepower nitrous system that my engine was built to handle and there'd be nothing left to discuss. My engine was built to handle 1,000+ horsepower and 9k rpm, yet I'm only asking it to deal with ~650 and 7.5k. Can you figure out why I did that?

Fatman0203

Hey Jim did you have the heads O-ringed? I know you dont NEED it for NOS, but it sure helps to keep everything inside, and not have those head gaskets go.

yzf-r1

iTrader: (1)

I'd be adding the 300+ horsepower nitrous system that my engine was built to handle and there'd be nothing left to discuss

I hope you would never stoop to that level, Jim...nitrous is

good point about the power delivery....I think you mentioned previously you probably were not going with the traction control system, however....granted the power delivery will be more linear, but traction will still be a serious issue on street tires

anyway, I don't want to hijack this into another 20B vs. V-8 thread (my apologies) so I'll shutup now

ZeroBanger

David,

Congrats on your decision to do the 20B, I think its great. I stopped over RotorMotors house over the weekend and saw his 20B in his garage that he is doing his conversion on. Its an awesome engine.

I will not be far from pettits shop, i'm going to consider a 20B in the future or a renesis swap (no flames) or an Elise.

XLR8

iTrader: (52)

WOW! Everything sounds great Dave!. I would consider a single initially. With the cost of retuning, and instalation, a few more man hours would be saved if done originally.

I'm sure the project will cost MAJOR $$$. Paying someone to work on your car is never cheap, especially when its a project of this scale.

All in all, I'm sure you will love it. The 20b FD definatly raises the staikes.

All I can say is ........Get lots of extra car insurance

jimlab

If all you care about is dyno bragging rights, who cares how you get there?

I have a Race Logic system, however whether or not I end up using it still remains to be seen.

bigmack000

your building the v8 fd to be a dyno queen ?

jimlab

No, completely the opposite.

bigmack000

ok good seem liek a waste if it was jsut a dyno queen.

SPOautos

Are you saying if you add 50% more air and fuel that your wont gain roughly 50% more power?

I think 20B3rdgen posted that link in reply to your statement about "I've yet to hear of one making that kind of power on pump gas" and "point me to the dyno sheet".

STEPHEN

diyman25

I really want to see DAVID's 20B RX7, steap by steap. so can evry one not jack this tread....

IN the REAL WORLD not thing "beat displacment"

Dont give me wrong I like RE so much(I even have PP. and single turbo) but when it come to make big HP, not too many thing can beat Americal IRON.

jimlab

Not unless you make significant changes to the system, and even then power potential is not necessarily linearly related to displacement.

Why does a 13B-REW make 255 horsepower @ 10 psi and a 20B only 300-320 instead of 380+ (a 50% increase over 255) at the same boost level? Because you're adding at least 50% more friction and the 20B's twins are no more efficient than those of the 13B-REW.

RotorMotor

iTrader: (5)

jim, we are not talking apples and apples when comparing the cosmos 20b, and the FD's 13b. yes you are adding 50% more friction, yes you are adding 50% more rotating mass, BUT the 20b's exhaust (and maybe intake ports... i cant remember) are smaller than in the 13b. also the 20b has 3 rotors and 2 sequential turbos... there is no efficiant way to split up that exhast with 2 turbos.

furthermore the 20b's turbos are not proportional to the FD's. the FD uses 2 hitachi 12's, but the 20b uses a ht-12 for the secondary and a ht-15 (only slightly larger) for the primary. basically the 20b's twins start running out of flow at around 5Krpm (if i remember correctly) and steadily drop to around 5 or 6PSI at redline. if the 20b's twins were efficiant & beefy enough to keep 10PSI till redline (and that motor was ported like the FD's 13b, you bet-cha that motor would be putting out that additional 50% (380HP).

SPOautos

Thats hard to say comparing stock to stock because I dont know the exact specs on things like intake and exhaust restriction for both vehicles, those both affect VE. I dont know exactly what the 20B makes at the wheels bone stock, but whatever it is I'd imagine its after more drivetrain losses since its prob in front of a automatic. The 3rd rotor is going to suffer the same frictional losses as the first 2 so each rotar should have the same capabilities for making power. I'm not talking stock cause I have no idea how they are set up stock. I'm talking about 2 modded setups where you would supply the same amout of a/f to each chamber, the 20b has 50% more chanber and gets 50% more air and fuel so it should make close to 50% more power. Obviouly it can be detuned and choked back...I'm sure they could set it up for just 150hp if they wanted to.

Ohhh yea, I believe Bryan at BNR he told me the stock 20b compressor wheels are actually smaller than the 13b wheels. I believe the ones Pettit uses are actually upgraded and adapted to work with the 20b manifold.....might be wrong though its been a long time since we talked about it.