Discussion
Was thinking about Jay Esterer's BMW V12, which got me speaking with a Benz tech who explained a couple of things about that new 600 benz biturbo v12. slightly higher than normal boost with cats it'll run 625bhp/740lbs-ft, which is all fine and well as anything with 5.5 litres and 12 cyls and 2 triple K turbos should put out stupid power, but the reason i perked up was that the whole motor, pipes turbos and heavy alternator come to about 560lbs dry.
motor's bulletproof by all accounts, can handle a lot more boost (check the AMG 65 motor, word is it's mostly more boost and that thing'll run 1000/1200). I have to admit that it's an expensive choice for an ultima at ~60K USD dressed and delivered, but I believe that any heavily prepped motor with this sort of power/reliability, whether nascar-style or street/feulie or bmw/jag v12 is going to approach 50-60K in any case. The ultima looks like a million bucks anyway right?
Of course all this power probably couldn't go through a G50 in any sort of trim i've heard of. How's Quaife/Hewland/Ricardo sequentials, anyone running this kind of gear in an ultima? I have been putting off calling Jay, I'm going to run this by him too offline..ht
motor's bulletproof by all accounts, can handle a lot more boost (check the AMG 65 motor, word is it's mostly more boost and that thing'll run 1000/1200). I have to admit that it's an expensive choice for an ultima at ~60K USD dressed and delivered, but I believe that any heavily prepped motor with this sort of power/reliability, whether nascar-style or street/feulie or bmw/jag v12 is going to approach 50-60K in any case. The ultima looks like a million bucks anyway right?
Of course all this power probably couldn't go through a G50 in any sort of trim i've heard of. How's Quaife/Hewland/Ricardo sequentials, anyone running this kind of gear in an ultima? I have been putting off calling Jay, I'm going to run this by him too offline..ht
Anyone considered popping a big rotary in one of these? Seems like the ideal platform in that the chassis is very capable and (imo) the GTR looks stunning. The power-weight side would be interesting.
2-rotor would be about 80kg
4-rotor ~150, add turbo(s) and make it ~165-180kg
From talking to someone who builds rotary engiens for a living a 4-rotor runnin 1-bar boost should manage ~800bhp or ~1000bhp/800 ft lb torque at 1.2bar.
Probably around 15-25k for the engine work though so it's be pretty expensive...
The more I think about this idea the more I like it
Possibly a project for late 2005 or 2006 so pie-in-the-sky for now.
Iain
2-rotor would be about 80kg
4-rotor ~150, add turbo(s) and make it ~165-180kg
From talking to someone who builds rotary engiens for a living a 4-rotor runnin 1-bar boost should manage ~800bhp or ~1000bhp/800 ft lb torque at 1.2bar.
Probably around 15-25k for the engine work though so it's be pretty expensive...
The more I think about this idea the more I like it
Possibly a project for late 2005 or 2006 so pie-in-the-sky for now. Iain
before we all get carried away (and i would love to be by this thread) will this motor fit? its great having a huge Merc bonnet to shoehorn stuff into but a tight GTR engine bay i another thing! has anyone got any mesurements of the fully dressed units?
not trying to pee on anyones fire, just Keepin it real!
Thanks Chris.
not trying to pee on anyones fire, just Keepin it real!
Thanks Chris.
chuntington101 said:
before we all get carried away (and i would love to be by this thread) will this motor fit? its great having a huge Merc bonnet to shoehorn stuff into but a tight GTR engine bay i another thing! has anyone got any mesurements of the fully dressed units?
not trying to pee on anyones fire, just Keepin it real!
Thanks Chris.
How tight is the bay? Not sure how big the v12 is but the 4-rotor is less that a metre long... I suppose losong a rotor and upping the boost might be an option is space it too tight.
Is the spec for the engine mounting position available online anywhere?
Iain
I am a huge rotary fan and considered doing a 3 rotor in my canam, but decided to go with an ls1. The rotary engine is not light.
Stock 2 rotor with accessories and turbos = 410 lbs
Stock 3 rotor with accessories and turbos = 561 lbs
6 inches longer than a 2 rotor (approx 666mm long, 2.1ft)
Of course the weight can be shaved down but they are not the paper weights everyone thinks they are.
If you look around www.rx7club.com and read all the threads where people are putting v8's in the rx7 you will find more arguments about weight than you will possible want to read.
Search this forum we have been through the rotary thing before. If you go the rotary route stick with a 2 or 3 rotor, at least they are production motors. You will notice most drag racers use 2 rotor and make 700+ rwhp. Several have tried 3 rotors and have come back to using a 2 rotor.
Your biggest problem is going to be heat + tuning. If you do go the rotary route please post pictures, I would love to see it.
iaint nice rx7. Sold mine to help pay for my canam.
Mark
Stock 2 rotor with accessories and turbos = 410 lbs
Stock 3 rotor with accessories and turbos = 561 lbs
6 inches longer than a 2 rotor (approx 666mm long, 2.1ft)
Of course the weight can be shaved down but they are not the paper weights everyone thinks they are.
If you look around www.rx7club.com and read all the threads where people are putting v8's in the rx7 you will find more arguments about weight than you will possible want to read.
Search this forum we have been through the rotary thing before. If you go the rotary route stick with a 2 or 3 rotor, at least they are production motors. You will notice most drag racers use 2 rotor and make 700+ rwhp. Several have tried 3 rotors and have come back to using a 2 rotor.
Your biggest problem is going to be heat + tuning. If you do go the rotary route please post pictures, I would love to see it.
iaint nice rx7. Sold mine to help pay for my canam.
Mark
mkoch1 said:
I am a huge rotary fan and considered doing a 3 rotor in my canam, but decided to go with an ls1. The rotary engine is not light.
Stock 2 rotor with accessories and turbos = 410 lbs
Stock 3 rotor with accessories and turbos = 561 lbs
6 inches longer than a 2 rotor (approx 666mm long, 2.1ft)
Of course the weight can be shaved down but they are not the paper weights everyone thinks they are.
If you look around www.rx7club.com and read all the threads where people are putting v8's in the rx7 you will find more arguments about weight than you will possible want to read.
Search this forum we have been through the rotary thing before. If you go the rotary route stick with a 2 or 3 rotor, at least they are production motors. You will notice most drag racers use 2 rotor and make 700+ rwhp. Several have tried 3 rotors and have come back to using a 2 rotor.
Your biggest problem is going to be heat + tuning. If you do go the rotary route please post pictures, I would love to see it.
iaint nice rx7. Sold mine to help pay for my canam.
Mark
Thanks for that info - it's something that's at the 'seriously considering' stage. Heat would certainly be a serious issue on a turbo'd rotary. One possibility is a short-crank peripheral port N/A quad - this would run a lot cooler but not generate much more than 5-600hp. 3-rotor dowelled with ceramic tips running higher boost would be good.
The V8 engines do sound great but I'm a rotary zealot! It'd be an interesting project although tricky and expensive which is why I'm looking at a reasonable time frame to do the research.
Problem with the drag engines in Oz are their life span - they might well put out silly power but they don't last long (like any drag engine!). I want somethign that's going to be fun on track. 450-600hp is easily more than I would be safe with now though. Got the FD almost fully sorted for track-days now so by the time I can take a step-up I should have enough experience to survive!
Iain
DAM, i was always though that rotors where much lighter than that! 500lbs for a triple? now i see why people are sticking to V8s insted of going with rotors. what is a reliable figure for power and torque for a turboed triple? i have had a look on RX7 club but not got many answers! do you guys thing that packaging a triplr in, mainly the turbo and coolers, would be a problem?
as for the Merc V12 (i must remember to wipe my mouth when reading this thread, i have marks on my keyboard now) has anyone got any pick of the thing out of a car? be nice to see where the turbos are mounted. also how the chargecoolers run. if its a similar size to the BM V12 then it would fit, and as long as the turbo packaging is ok (or can be fabbed) then it could be a runner!
Thanks Chris.
as for the Merc V12 (i must remember to wipe my mouth when reading this thread, i have marks on my keyboard now) has anyone got any pick of the thing out of a car? be nice to see where the turbos are mounted. also how the chargecoolers run. if its a similar size to the BM V12 then it would fit, and as long as the turbo packaging is ok (or can be fabbed) then it could be a runner!
Thanks Chris.
chuntington101 said:
DAM, i was always though that rotors where much lighter than that! 500lbs for a triple? now i see why people are sticking to V8s insted of going with rotors. what is a reliable figure for power and torque for a turboed triple? i have had a look on RX7 club but not got many answers! do you guys thing that packaging a triplr in, mainly the turbo and coolers, would be a problem?
Thanks Chris.
500lbs+ is with all the accessories, ac, ps,etc. The stock turbos are also very heavy. If you ran a large single turbo and removed all the accessories you could cut allot of weight.
www.pettitracing.com sells a 3 rotor conversion. I believe they claim 550 rwhp at 10 psi.
More people are putting v8's in rx7 because it's cheap reliable power. Stock rx7 makes about 250 hp, with a horribly complicated sequatial turbo system. Dam thing has over 60 vacuum lines running it. Stock ls1 makes 320hp. In most cases the v8 only add a minimal amount of weight if any. Biggest complaint about rotaries is the lack of torque. Rotaries are great at making power but are delicate motors that require a good tuner. Water seal and apex seal failures give them a bad name. The motor itself is not bad but overheating and bad tuning cause allot of motors to pop. The bad wrap the motor gets is mainly due to the owners / tuners not knowing what they are going when they start to modify it.
I think a 3 rotor would fit in a gtr pretty easily. Just a word of caution you may find the factory to be not so rotary friendly. Search the old posts.
Mark
Counting the a/c and ps in with the engine weight is a tad unfair. One of the engine builders I know has built a quad-rotor that will be running n/a with carbs at first and then efi later on. The base weight for then engine without carbs is 150kg (330lbs).
Adding rotors does wonderful things for torque on a rotary As you point out - most of the problems come from poor maintenance and badly conceived mods.
I'll have a search for past threads on Ultima and rotary engines. I wouldn't expect the same level of service using such a non-standard part as a wankel but I wouldn't expect them to make it too hard either!
Cheers,
Iain
>> Edited by iaint on Wednesday 29th September 16:43
Adding rotors does wonderful things for torque on a rotary
As you point out - most of the problems come from poor maintenance and badly conceived mods. I'll have a search for past threads on Ultima and rotary engines. I wouldn't expect the same level of service using such a non-standard part as a wankel but I wouldn't expect them to make it too hard either!
Cheers,
Iain
>> Edited by iaint on Wednesday 29th September 16:43
Well I still like the idea of a twin turbo lexus v8 (1UZFE, hello >9k rpm and 1hp per Kg). Apparently I have to pass emmissions though 
If you wanna spend 60k on an engine, why not just get a judd v10 or a falconer v12 or something?
Rotary, a 4rotor would be very interesting but yeh rotories aren't as light as everyone thinks they are. Would be good if someone did this.
If you wanna spend 60k on an engine, why not just get a judd v10 or a falconer v12 or something?
Rotary, a 4rotor would be very interesting but yeh rotories aren't as light as everyone thinks they are. Would be good if someone did this.
Mr J, got any links to Judd and the other web site? also how much would one of these things cost? thats the nice thing about production engines, there are (relativly) cheap and in large supply. race engines are graet for racing, but for a machine deigned for the road and track, i would go for a road engine! at least with a road unit, you are more likly to pass emmitions and rebuilds will be a lot less frequent. the last factor is worth baering in mind when thinking of a race over production engine on a cost basis.
thanks Chris.
thanks Chris.
Well I haven't had a chance to follow up on this, sorry for the tease and sorry for the long note here.:
> The merc motor will likely fit dimensions wise,
> no clue on standing trans issue (what handles 700-1000 lb-ft AND has five or more forward gears in a GTR)
> turbo plumbing would have to change a little putting it in the middle but hey, little kkks can fit about anywhere.
Reasons why I'd look at this Merc:
>Over the judd
-judd isn't exactly streetable
-nor will it pass a smog just about anywhere,
-a v8 isn't quite what i had in mind
-and a v10 is end to end vibration even if 72deg
>Over the Falconer
-90 degrees is not what i'm looking for in a v12
-block too long, deck too tall
-note: worth asking the brammo guys,they've done an ultima and they're involved with that motor (separately)
>Generally
-don't want a race motor on the road
-want to run pump 92-93 USA octane daily
-car must idle (manhattan much of the year)
-should run very smooth, not explode, road car
-flat plane, cross plane, it doesn't matter to me as i already have a nice thoroughbred v8, and in the US there are plenty of rumblers and screamers both, i want that v12 orchestra!
-would like to have option to run JP and silly boost when necessary (OK, maybe not necessary)
-target macca f1 refinement
I have to differ on the point re: torque in a 1 tonne car, given the option or loophole many teams would take a restrictor plate motor running more torque than hp, cause all those lbs-ft all over the rev range keep you moving constantly forward all the time, no matter what gear you're in. However, in a road car is precisely where you need that kind of torque, just in case you need to pull the trailer you drove the ultima to the track in home. haha. I'd argue that in the road car you in fact have no need for all those ponies, but neither argument really flies, ever, as you want as much of both as possible as often as possible, which is why i love this motor. more torque = more streetable, but not if it blows your trans!
and re: 120kph burnouts, i reckon 6 speeds final for about 400kph you'd still bark the tires into 3rd gear near 160+ I saw a corvette years ago with only(!) 600 lbs-ft smoke it up at full on highway speeds, owner said john lingenfelter and I said yeah that's what's up.
It's just me, as even though I love Mouse and Rat motors in hotrods and old vettes, I look at this car and the evil me wants to put something exotic in one of these things, something extreme, something that can really scream on race gas and get tuned down(!) to 625 to run on pump if need be (or v.v.), that goes and goes without rebuilds. Is the merc motor the right one for the ultima as it stands? Almost definitely not, considering the car has had several years of development exclusively around the SBC there's no good reason not to go with the amerspeed engine, especially since the new 377 will apparently put out 700+ hp and rev like a bandit. How it idles who knows, or handles bumper to bumper with the A/C on in LA or Phoenix or, let's say Dubai. Consider my speculation to be idle then, since there is no good reason to try the merc motor over the amerspeed or other proven platform, there is no good reason to fool with what is a very quick package in general. This is the prevailing wisdom. But there is no really GOOD reason to build one of these ultimas either, still if I were to do so, I'd want mine to be BAD. Does that mean titanic twin turbo v12 action? Maybe it means I steal some engineers and hatch a diabolical scheme to get a couple of hayabusa motors in there. Maybe that means amerspeed 350 stocker and i paint it black and put in a gun rack, who knows, but in the beginning, definitely keep it simple right? So probably none of the above, buy someone's ready built ultima-spec drive and see what makes these GTRs tick, then decide if it's worth the R&D and the risk to life of driving something with unproven dynamics.
But if any of you go and buy a benz biturbo v12 and jam it in your GTR please for posterity's sake post a build diary! ..ht
> The merc motor will likely fit dimensions wise,
> no clue on standing trans issue (what handles 700-1000 lb-ft AND has five or more forward gears in a GTR)
> turbo plumbing would have to change a little putting it in the middle but hey, little kkks can fit about anywhere.
Reasons why I'd look at this Merc:
>Over the judd
-judd isn't exactly streetable
-nor will it pass a smog just about anywhere,
-a v8 isn't quite what i had in mind
-and a v10 is end to end vibration even if 72deg
>Over the Falconer
-90 degrees is not what i'm looking for in a v12
-block too long, deck too tall
-note: worth asking the brammo guys,they've done an ultima and they're involved with that motor (separately)
>Generally
-don't want a race motor on the road
-want to run pump 92-93 USA octane daily
-car must idle (manhattan much of the year)
-should run very smooth, not explode, road car
-flat plane, cross plane, it doesn't matter to me as i already have a nice thoroughbred v8, and in the US there are plenty of rumblers and screamers both, i want that v12 orchestra!
-would like to have option to run JP and silly boost when necessary (OK, maybe not necessary)
-target macca f1 refinement
I have to differ on the point re: torque in a 1 tonne car, given the option or loophole many teams would take a restrictor plate motor running more torque than hp, cause all those lbs-ft all over the rev range keep you moving constantly forward all the time, no matter what gear you're in. However, in a road car is precisely where you need that kind of torque, just in case you need to pull the trailer you drove the ultima to the track in home. haha. I'd argue that in the road car you in fact have no need for all those ponies, but neither argument really flies, ever, as you want as much of both as possible as often as possible, which is why i love this motor. more torque = more streetable, but not if it blows your trans!
and re: 120kph burnouts, i reckon 6 speeds final for about 400kph you'd still bark the tires into 3rd gear near 160+ I saw a corvette years ago with only(!) 600 lbs-ft smoke it up at full on highway speeds, owner said john lingenfelter and I said yeah that's what's up.
It's just me, as even though I love Mouse and Rat motors in hotrods and old vettes, I look at this car and the evil me wants to put something exotic in one of these things, something extreme, something that can really scream on race gas and get tuned down(!) to 625 to run on pump if need be (or v.v.), that goes and goes without rebuilds. Is the merc motor the right one for the ultima as it stands? Almost definitely not, considering the car has had several years of development exclusively around the SBC there's no good reason not to go with the amerspeed engine, especially since the new 377 will apparently put out 700+ hp and rev like a bandit. How it idles who knows, or handles bumper to bumper with the A/C on in LA or Phoenix or, let's say Dubai. Consider my speculation to be idle then, since there is no good reason to try the merc motor over the amerspeed or other proven platform, there is no good reason to fool with what is a very quick package in general. This is the prevailing wisdom. But there is no really GOOD reason to build one of these ultimas either, still if I were to do so, I'd want mine to be BAD. Does that mean titanic twin turbo v12 action? Maybe it means I steal some engineers and hatch a diabolical scheme to get a couple of hayabusa motors in there. Maybe that means amerspeed 350 stocker and i paint it black and put in a gun rack, who knows, but in the beginning, definitely keep it simple right? So probably none of the above, buy someone's ready built ultima-spec drive and see what makes these GTRs tick, then decide if it's worth the R&D and the risk to life of driving something with unproven dynamics.
But if any of you go and buy a benz biturbo v12 and jam it in your GTR please for posterity's sake post a build diary! ..ht
Hey guys,
Just stumbled back on this forum and saw this thread. I wanted to say that the reason Rotaries are not so light is because of the extensive use of cast iron.
Many of the blocks they are being compared to are made of aluminium so naturally the iron parts are heavier. Also the reason for the rotary would be reliability. There are much less moving parts as everyone knows in the rotary.
On the reliability side. Yes, turbo'ed rotaries are unreliable due to rotaries nature of being weak to detonation. N/A rotaries on the other hand are very reliable, I would even go as far as saying they are more reliable that 90% of piston engines out there.
On a personal note. I am a rotorhead/heart so yes I am biased but I do love the new LS7. When I visited BigAl I think his forum name is the Canadian GTR, I had in mind of using a Supra engine or a Skyline engine. But after measuring the dimensions given by the chassis I saw that these would be very difficult options.
However, the dimensions the Ultima gives seems to be perfectly made for a 26b derivative 4-Rotor. A 3 Rotor Single Turbo could also be used 20b. Regardless, a 4 Rotor PP'ed Motor would be putting out around 600 crank HP which I think is more than enough in an Ultima. A turbo'ed 3-Rotor with a well matched turbo something like the GT42 series would be hitting 600+ hp at the wheels.
Sorry for my seemingly discombobulated writing but I just wanted to say that someone mentioned "Pettit Racing". Their claims at 550hp @ 10psi on stock twin turbos is false and physically impossible and has been proven so on rx7club.com.
Cheers guys,
Alex
Just stumbled back on this forum and saw this thread. I wanted to say that the reason Rotaries are not so light is because of the extensive use of cast iron.
Many of the blocks they are being compared to are made of aluminium so naturally the iron parts are heavier. Also the reason for the rotary would be reliability. There are much less moving parts as everyone knows in the rotary.
On the reliability side. Yes, turbo'ed rotaries are unreliable due to rotaries nature of being weak to detonation. N/A rotaries on the other hand are very reliable, I would even go as far as saying they are more reliable that 90% of piston engines out there.
On a personal note. I am a rotorhead/heart so yes I am biased but I do love the new LS7. When I visited BigAl I think his forum name is the Canadian GTR, I had in mind of using a Supra engine or a Skyline engine. But after measuring the dimensions given by the chassis I saw that these would be very difficult options.
However, the dimensions the Ultima gives seems to be perfectly made for a 26b derivative 4-Rotor. A 3 Rotor Single Turbo could also be used 20b. Regardless, a 4 Rotor PP'ed Motor would be putting out around 600 crank HP which I think is more than enough in an Ultima. A turbo'ed 3-Rotor with a well matched turbo something like the GT42 series would be hitting 600+ hp at the wheels.
Sorry for my seemingly discombobulated writing but I just wanted to say that someone mentioned "Pettit Racing". Their claims at 550hp @ 10psi on stock twin turbos is false and physically impossible and has been proven so on rx7club.com.
Cheers guys,
Alex
After hearing the C6R in person I can't be against the LS7 line.
But there unless you have experience a 4 rotor it is unimaginable. Sure the SBC is a great engine for $/#'s, but it is alot like the 2jz. Everyone goes around saying ahh it can easily make these #'s on stock ... .... but usually that turns out to be far from true.
When I see cars like Mr. Schwartz's I am seriously mixed between death-like fear and respect. I would never want to drive a 1,000+hp car on the street and yet his install/setup is nice clean and makes insane numbers. 600 will be more than enough to please me
But there unless you have experience a 4 rotor it is unimaginable. Sure the SBC is a great engine for $/#'s, but it is alot like the 2jz. Everyone goes around saying ahh it can easily make these #'s on stock ... .... but usually that turns out to be far from true.
When I see cars like Mr. Schwartz's I am seriously mixed between death-like fear and respect. I would never want to drive a 1,000+hp car on the street and yet his install/setup is nice clean and makes insane numbers. 600 will be more than enough to please me
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