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This Noob Is Crazy!


Guest Gollum
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Great project, I'm also watching on the edge of my seat smile.gif

Also a fan of the Z (have a 300 in the garage that doesn't get out as much as it used to), I think it would be a great platform although heavy in the frame compared to a mini, there's also as much room as you would need (putting in the Corvette V8 is relatively common isn't it?), and it looks awesome

But would running both outputs to a common shaft increase the torque on your transmissions? I guess if you have one piston from each motor firing at the exact same time it would divide the torque into the two, but if it's staggered at all then the first would bear the full weight I would think

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So, I did up a little spread sheet.

You can play with your tire height, and all three ratio points. It calculates your tire circumference and resultant Rear Wheel RPM at various speeds (in MPH for your convenience :offtopic:). It then takes your input ratios (in reverse order) to give you the engine RPM at those speeds. Green figures you can change, red are formulas (leave them unless you see an error).

Now, I don't know all the formulas needed to calculate the actual torque being applied, but it will help you in figuring out what needs to be done where.

From the quick groupings I did, it looked like you wanted the tallest rear (smallest value), and some very tall mid and primary gears, or your engine RPMs get ridiculous. Good news is that having close to 1:1 ratios up front means small sprockets. Gives you more space to work.

Let me know what you think, and if I forgot anything. Have fun!

EDIT: Oh, bollocks. I goofed. That would not give you engine RPM, but output shaft RPM. 6th Gear would be the closest to true considering it's ratio of 0.965:1. I'll fix that in a minute or two.

Ratios.xls

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That is REALLY sweet.

Running a midship setup isn't really an option for me, and I don't think it's smart to be running a chain all the way back from the front.

Though that does make me think...

I could still use something similar. Have the engines in the bay like I was planning, but run both sprockets out to a common rotating shaft and make that shaft run back to the transmission tunnel. Sounds easy when I think of it like that. Then I can even use stock sprocket parts, no modification necessary!

The only question I have, would be how compact I could make it all, and how much will I have to offset the engines to make room for that setup. I think I'll be fine, as the Z has plenty of room to work with, and since it's a bike engine I can fudge the rotation of the engine quite a bit.

You guys have already been a good help!

Thats what I was picturing. A jackshaft setup like this blue car with a driveshaft running to the rear end. Here's a picture of a twin bike engined caterham doing something similar. Actually, this would should give you your flat plane sound since a flat plane V8 is pretty much two inline 4's joined at the crankshaft!

6569_1108833363789_1315492114_30280109_3448732_n.jpg

The Z does have a looooooong nose!

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Well, things have gotten quite a bit more complex, but I believe I have gotten the spreadsheet to take the internal primary, and each (selectable) individual gear ratio into consideration.

I've even tried a different layout to make it a little more user friendly. I also left the listings of the factory (internal) gear ratios at the bottom for quick reference (and don't delete them :rolleyes:). Although, all you need to do is use the drop down to select the gear you wish to see the mph:rpm ratings for. Obviously, you can change the other specs on the left as well...

Let me know if you have any questions! :blink:

Ratios.xls

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That's a wonderful calculator!

So, if the primary reduction is completely internal, then gear ratios will be easy to achieve. If that's the case then it looks like I can just use a mid ratio in order to get RPMs where I want them with a 3.7 rear diff (the easiest ratio to find a clutch LSD unit for almost any nissan diff carrier).

A .5 mid ratio would give me about 4,100 rpm at 65mph in 6th. I'm going to be able to make that mid sprocket pretty darn small...

Does anyone have any info on the stock EFI? Has anyone cracked it? I've seen people talking about PC II and PC III but I haven't researched it yet. I'm assuming it's some sort of piggy back. I plan on running the stock EFI for NA application if I can, but if I can't make some custom maps then I'll probably be using either megasquirt, or adapting some OEM system that's already easily programmable.

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Keep in mind 4100 RPM is just the start of the usable power this motor makes. With the turbos that might be fine, but with just the dual motors, I'd suggest some shorter gearing and bring that up... You also don't need to be geared to hit 200+ (or do you?).

I just noticed something that might look a bit confusing. My labeled "Primary Ratio" in the spec range refers to the first external sprocket set. The factory internal "primary ratio" is just that. Internal. I didn't notice that until reading your post. The 1.939 factory internal primary is already taken into the calculation. The value in the box is adjustable as it would be the first stage of external gearing.

I'm also not sure what having a .5 stage would do to your torque output. I'm not certain that a 3.7 immediately following would recoup that halving of power. I imagine that halving the ratio would make it much harder to turn that shaft. There by placing undue stress on the sprockets and chain. I'd keep all the gears about as close to one another as possible. Get the tallest rear you can get your hands on, and try to keep the mid gears closer to 1:1. Anything on the positive side of 1 should be beneficial.

Try these figures:

23.7

3.7

.85

.9

6

156.4

156.4mph would be your theoretical limit, if your rebuilt motors had the same 11,750RPM redline. That would also put your 65mph cruising rpm at just under 4900.

I'm not sure if the numbers are perfect, but here is a dyno run for a stock bike:

dyno-2002-hon-vfr800.gif

The HP difference between 4100 and 4900 is almost 10hp. That shorter gearing would make same gear passing much easier. VTEC (if you didn't mess with it) would kick in at ~90 mph in 6th. ~68mph in 4th, and ~60mph in 3rd. Then you would get the full pull through 3rd, up to ~100mph.

Maybe an actual engineer will stumble through here and voice their opinions...

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I was thinking the same thing. I was just stating that the ability to go down as far as .5 and still have acceptable ratios shows that I should have quite a window to work with. Keeping the ratios as close to 1:1 as possible while achieving the cruising speeds desired would be the goal, not limitation.

I think in the end I'll probably end up with a 3.364 final ratio. What will be challenging is that if I use the car that I have available to me now, then it's got ZERO suspension, which is good and bad. It gives me a chance to built it the way I want from the first place, but it also means I'd need to source an original 3.364 R180, which is considerably easier than a 3.364 R200 but still hard. But then I'd also be want to get a CLSD R180 from a subie, and swap over the LSD carrier with the nissan gear set. Those get pricey. I'll end up with a good $800+ just in the diff setup, but it'll be bulletproof.

Oh, correction. Tire size will be closer to 23.9"

So with 23.9 3.364 .9 .9 I can still be abover 7k in 3rd gear at 65mph, and in 6th gear 65mp is 4,660. I think that's in the acceptable range. I don't need to be geared for 200mph, but I also want to keep the RPMs as low as reasonable possible for the engine. But obviously I'm not going to give up the usability of my gears, so this seems close to the range I want to be.

By comparison, if I was building a LS2 V8 with a T56 transmission I'd be shooting for around 1,800 at 65rpm, due to that transmission's .5 OD. At those RPM levels there are guys knocking back well over 30mpg with over 400hp to the wheels. Not to mention the wear benefits of those RPM.

Regarding the T-Rex. Seems like a nice toy, a very cool and fast toy too. A Z is a very different animal though. I don't want to say better, because I truly believe there never is such a thing as "best". There might be better for some than others, but you can never say something is the best, period. The Z is just more to my liking. I like the chassis dynamics. I like the disposable nature of them. I like the simplicity of the car, and how it just works the way it is. They can be built as very competitive cars at almost any level, and the people tuning them have gotten them so refined that they keep getting bumped up classes, even to this day.

Oh, and someone said earlier in the thread, something like "isn't the SBC swap common?" Yes, yes and yes. That being said, here's a list of swaps I've seen:

LS1, LS2, LS6

VG30E, VG30ET, VG30DE

SR20DET

KA24ET, KA24DET

Ford 289, 302, 351W 5.0 etc

Chevy Big block - all sorts, even twin turbo'ed

Ford 4.6 Mod motor (Lincoln DOHC all aluminum)

Mopar 340, 318

Mopar 440

RB25DE, RB25DET, RB26DETT, RB30DETT

Mazda 13B-RE

Ford Lima Turbo 4

VQ35DE

Any Chevy small block you can think of

VH45DE

1UZFE

2JZGTE, 1JZGTE

7MGTE

Viper V10

And one of my favorites:

Jag V12 (only two of these that I know of)

There's more I'm sure. That's just all the swaps done I can think of off the top of my head. These cars are engine whores. Space for anything you can dream pretty much. The Ford Mod Motor was one of the tightest fits I've seen. If I were to do it myself, I would have tube framed the front of the car.

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I know this isn't really the forum for this, so if I offend a lot of people I completely understand.

What does everyone think about the V-Max engine? It's not nearly as technically advanced imo, and I really don't like the idea of dealing with carbs, but I'm wondering if the added displacement/hp/torque would be worth it. It's also a shaft driven bike, which might make it easier to adapt. I have a feeling it wouldn't be any easier though, just different.

The output faces the wrong way for mounting the engines in a V8 longitudinally in the engine bay. The easiest way I can figure doing it, would be use the same cradle design idea I've got worked up for the VFR engine, and have a suspended front shaft that has a 90 degree meshed gear for each engine. I'd have to make a custom differential style gear for the output shaft of the engines, and a corrosponding gear on the shaft that's going to connect to the driveshaft.

It seems like it'd be a simpler engine to engineer some parts for though, like the exhaust manifolds and the engine cradle. It's a physically larger engine, but that might not pose a problem. It's a 5 speed instead of a 6 speed, but it's still pretty close ratio, but the rev limit isn't as high so I think the 6th gear won't be missed too much.

The main downside I'm seeing though, is that it seems their engines aren't nearly as available and affordable compared to the VFR engines, which seems surprising considering how much some people brag about the sales of the V-Max....

Overall it seems they make about 30-40% more power compared to the VFR, and it's all due to torque from displacement. Not because it's "better" in any way. Let me be the first to admit, I prefer the VFR engine, but for my project I'm just weighing my options.

Opinions and facts welcome.

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Well, if you're going to use a VMAX engine, you might as well use the new 1700 version. 200 hp, fuel injected, torque meister. I haven't seen one in a car yet, but it has to be one of the best motors to use in one.

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well considering the cost of the current 95-05 engines I'm finding, I don't think the new engine is going to be cost effective.

If I wanted to spend 10k on this, I'd just build a flat plane crank LS1.

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well considering the cost of the current 95-05 engines I'm finding, I don't think the new engine is going to be cost effective.

If I wanted to spend 10k on this, I'd just build a flat plane crank LS1.

Well, how much are F355 engines going for these days? :beer:

I don't really see why someone would want to build a flat plane crank LS1. I know these engines make tons of power, but I would think a smaller V8 with a multivalve head and a shorter stroke would make a much better flat plane base. Why would you want a flat plane V8 if you can't rev the thing to 10K?

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Oh, just incase you didn't already know... Since you're going to use a VTEC motor, make sure you get the same revision. 2002-2005 are the same, but the ECU (and maybe more) changed from 06+

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well considering the cost of the current 95-05 engines I'm finding, I don't think the new engine is going to be cost effective.

If I wanted to spend 10k on this, I'd just build a flat plane crank LS1.

Well, how much are F355 engines going for these days? :cool:

I don't really see why someone would want to build a flat plane crank LS1. I know these engines make tons of power, but I would think a smaller V8 with a multivalve head and a shorter stroke would make a much better flat plane base. Why would you want a flat plane V8 if you can't rev the thing to 10K?

Because you actually can make a LS1 rev to 10k reliably. Circle track guys have been doing it for decades, which also means it's pretty cheap to do compare to say... a 1UZ or VH45. With those you're buying FOUR custom made camshafts with THIRTY TWO springs, and their' timing setup is always more complicated. With a SBC, SBF, or LS engine you just throw in some cam gears to replace the chain, a $300 camshaft, and a $1,000 valvetrain kit consisting of the super lightweight pushrods, roller rockers, and the strongest for their weight springs available.

The big upside to something like these engines though, is that most of the parts are commonly available, and affordable. And another HUGE upside is bore size. If you wanted even a MILD stroke comparable to a Ferrari stroke, then you've got well over 5 liters to play with. Even at 8k that's going to be making more power with stock LS1 heads over a 3-4 liter Ferrari reving to 11k. Shorten the stroke to reduce vibration caused from the flat plane design and you still have 4+ liters and an engine that won't rattle your fillings loose (Ferrari engines tend to be quite buzzy, but it's well compensated by their spacecraft quality mounting). Shortening the stroke obviously has it's other benefits, that the engine will rev easier and the pistons & rings will last longer.

But really, even a 2 valve LS1 head can outflow a 5 valve Ferrari head, once to take into account the fact that most Ferrari V8's are very small displacement and they're not running NEARLY the oversquare design most bike engines are running, which is why even Ferrari engines have a hard time beating a basic F20A Honda engine for HP/Liter.

That being said I'm not bagging on Ferrari. They have their engines, but a lot of their stuff just makes me go "who cares". Their consumer stuff has never been farther from their race stuff in history. If I was going to spend $20,000 on a used engine, I'd expect it to reach at least 110% volumetric efficiency.

Oh yea, did I mention a guy I know was going to build a flat plane crank LS1? He's going to be running around 4 liters iirc, and build it to live around 8k all day long, and is projecting over 500hp. He's a machinist for a living, and a well respected head porter, so I'm sure his costs will be about as low as they get, and I still think I could do this for less than half what he'll spend. I won't have the power potential, but we both have different goals in mind for different projects.

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FWIW, there's guys making over 550hp out of stock LS1 heads and blocks, which means they're pushing almost 100hp per liter, and with relatively low RPM. Those heads can FLOW.

Back to what this post was for. I think the Vmax engine just doesn't suit me. The fact it's not a 90 degree engine is what's really killing it for me. That and the price. I can't believe what some people want for those engines! I don't see them as THAT special.... I'd rather just use the VFR and know that if I pop one or both that replacements are available and cheap. As long as the fabricated parts for the swap don't break, then I shouldn't have to worry about any high cost injuries to parts. And from what I've seen these engines are very reliable for the RPM they spin.

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For those itching to SEE something, this is the best I got thus far. This is the dyno I'd be hoping to see with twin turbos (crank estimate, not wheel).

V8R1600.jpg

Turbos would be twin T3 50 trim turbos. Should be a good turbo from 325-450hp, and could probably reach 550hp, but would be well out of it's efficiency by that point, which would be pushing it on the VFR's compression. This is what my current turbo map plot looks like:

Turboplot.jpg

That plot is getting max boost by 6k, and achieving 400hp by 10,500.

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well considering the cost of the current 95-05 engines I'm finding, I don't think the new engine is going to be cost effective.

If I wanted to spend 10k on this, I'd just build a flat plane crank LS1.

Well, how much are F355 engines going for these days? :cool:

I don't really see why someone would want to build a flat plane crank LS1. I know these engines make tons of power, but I would think a smaller V8 with a multivalve head and a shorter stroke would make a much better flat plane base. Why would you want a flat plane V8 if you can't rev the thing to 10K?

Because you actually can make a LS1 rev to 10k reliably. Circle track guys have been doing it for decades, which also means it's pretty cheap to do compare to say... a 1UZ or VH45. With those you're buying FOUR custom made camshafts with THIRTY TWO springs, and their' timing setup is always more complicated. With a SBC, SBF, or LS engine you just throw in some cam gears to replace the chain, a $300 camshaft, and a $1,000 valvetrain kit consisting of the super lightweight pushrods, roller rockers, and the strongest for their weight springs available.

The big upside to something like these engines though, is that most of the parts are commonly available, and affordable. And another HUGE upside is bore size. If you wanted even a MILD stroke comparable to a Ferrari stroke, then you've got well over 5 liters to play with. Even at 8k that's going to be making more power with stock LS1 heads over a 3-4 liter Ferrari reving to 11k. Shorten the stroke to reduce vibration caused from the flat plane design and you still have 4+ liters and an engine that won't rattle your fillings loose (Ferrari engines tend to be quite buzzy, but it's well compensated by their spacecraft quality mounting). Shortening the stroke obviously has it's other benefits, that the engine will rev easier and the pistons & rings will last longer.

But really, even a 2 valve LS1 head can outflow a 5 valve Ferrari head, once to take into account the fact that most Ferrari V8's are very small displacement and they're not running NEARLY the oversquare design most bike engines are running, which is why even Ferrari engines have a hard time beating a basic F20A Honda engine for HP/Liter.

That being said I'm not bagging on Ferrari. They have their engines, but a lot of their stuff just makes me go "who cares". Their consumer stuff has never been farther from their race stuff in history. If I was going to spend $20,000 on a used engine, I'd expect it to reach at least 110% volumetric efficiency.

Oh yea, did I mention a guy I know was going to build a flat plane crank LS1? He's going to be running around 4 liters iirc, and build it to live around 8k all day long, and is projecting over 500hp. He's a machinist for a living, and a well respected head porter, so I'm sure his costs will be about as low as they get, and I still think I could do this for less than half what he'll spend. I won't have the power potential, but we both have different goals in mind for different projects.

I wouldn't argue with the fact that you can build an LS1 for much less than a quad cam V8, the parts to make them go fast are already there as the engine is well supported by the aftermarket. I wasn't aware that you could make them rev to 10K RPM reliably, I always thought you had to have a NASCAR budget in order to do so.

I was joking about the Ferrari thing, seems like most manufacturers have accomplished what Ferrari has for a fraction of the price(BMW, Audi, Honda, etc.) Now if only Honda would build a V8 using the F20C heads and a flat plane crank....

Back to your project, how are you planning on plumbing the turbos? Will you have each turbo running off a shared(between two engines) bank?

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Gollum, my guess is that the price differential is due to the likelyhood that more V-Max's are crashed or blown up than VFRs, hence more of a market for their powerplants. I've known of wreckers (breakers) here in Australia sitting on VFR motors for years because there's just no-one buying them.

Well, some buggy builders use them, this one has a CBR954 motor but there's quite a few running VFR motors:

Rick%20Schenker%20Piranha%204.jpg

One of these with your flat-plane VFR-V8 would be a bit of fun :blush:

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Gollum, are you secretly me?

For about 3 years now I've been planning a twin VFR-engined, twin supercharged Mini, with a curb weight around 1000lbs and packing at least 600hp. Ever since I was on the Formula SAE team at college, I've wanted to build a car of my own that would perform in the same way, but with the ability to blast around on public roads. There is just nothing like being able to turn as hard & as fast as you can at 60mph without even so much as tire squeal.

Remember that the VFR800 powerplant is actually 90º -- it's the RC45 that has a 180º crank. Unless you make a custom crank for this engine, you won't get it to sound like a Ferrari.

As far as power is concerned, I don't advertise this, but I've seen 167hp at the wheel on my supercharged setup -- that's right around 190hp at the crank. There's no doubt in my mind that the stock internals can handle 200+hp. With the Mini project, I was planning on running forged pistons & rods, and also adding an intercooler, and then 300hp per engine should be cake with pump gas.

BTW, I love the LS1s as well, and plan on doing the E36 M3 swap in the next few years.

Good luck with your project.

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there's definitely no shortage of ideas out there.

here's a guy that put a chainsaw motor on his bicycle:

chainsaw.jpg

look at this POS hack job. it's got a weed wacker motor and a swingarm made of rebar:

weedwackerandrebarhackjob.jpg

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For about 3 years now I've been planning a twin VFR-engined, twin supercharged Mini, with a curb weight around 1000lbs and packing at least 600hp.

I've been dreaming about something similar for a long time as well, turbo VFR in one of these... NSU TT.

5609_1111592072755_1315492114_30287743_4282121_n.jpg

They're already rear engined, and weigh less than 1500 lbs stock, similar to a mini.

Sorry if you're thread is getting slightly jacked Gollum, but you opened up a can of worms with this one!

As far as the 180 vs. 360 crank goes, doesn't the ST1300 engine use a 360 degree crank? I would imagine this engine could be coerced into making some serious power.

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Gollum, are you secretly me?

For about 3 years now I've been planning a twin VFR-engined, twin supercharged Mini, with a curb weight around 1000lbs and packing at least 600hp. Ever since I was on the Formula SAE team at college, I've wanted to build a car of my own that would perform in the same way, but with the ability to blast around on public roads. There is just nothing like being able to turn as hard & as fast as you can at 60mph without even so much as tire squeal.

Remember that the VFR800 powerplant is actually 90º -- it's the RC45 that has a 180º crank. Unless you make a custom crank for this engine, you won't get it to sound like a Ferrari.

As far as power is concerned, I don't advertise this, but I've seen 167hp at the wheel on my supercharged setup -- that's right around 190hp at the crank. There's no doubt in my mind that the stock internals can handle 200+hp. With the Mini project, I was planning on running forged pistons & rods, and also adding an intercooler, and then 300hp per engine should be cake with pump gas.

BTW, I love the LS1s as well, and plan on doing the E36 M3 swap in the next few years.

Good luck with your project.

I don't think I'm you, though I just finished watching "The Prestige" which has me wondering...

I have no intentions of starting an argument, lets just get to the bottom of this like civilized adults shall we? By judging from the firing pattern listed in the FSM for the VFR800 02-05, and the degrees of rotation between fires, I'd say it's a guaranteed flat plane crank. And as I've stated, getting a Ferrari firing pattern IS definitely doable, which is impossible without a flat crank design.

These are pictures taken from the FSM's crankshaft section:

crank1.jpg

Crank2.jpg

If the crank were indeed NOT a flat design, it probably would be a 360 degree design, giving each cylinder it's own journal. Honda did this with their larger displacement V4 cruiser, name of which escapes me right now. THAT V4 sounds smooth as silk, not burly and muscular like the VFR, which is around half the displacement. As you most definitely know, it comes down to the firing pattern. The VFR engine is running as an incomplete flat V8 already, and ends up firing nothing close to symmetrical. It fires both cylinders on one bank, then the next two on the other bank, this is the only way to achieve a decent spread firing pattern on a V4 engine with a flat crank.

Firing patter and spacing:

1 - 180Degrees - 3 - 270Degrees - 2 - 180Degrees - 9 - 90Degrees (back to 1)

The cylinder numbering has odd on one side, even on the other.

The 270 and 90 degree separations are what's giving the engine it's rough sound, extremely different from the domestic V8 engines these V4's sound is commonly compared. A domestic's rough sound is created by the fact the engine is firing unevenly. It fires evenly until it burps, two cylinders on the same bank fire back to back without the other bank firing, then it's even, then it burps again, the other bank has two sequential fires as well.

The domestic V8 can "theoretically" achieve a flat crank sound with 180 degree heads, that correct the exhaust pulses, but in theory, practice and theory are the same, but in practice they're not. No matter how good the exhaust will sound, the engine itself has it's inherent nature already determined by the crank. No matter how loud the exhaust, the sound of the engine itself is off.

I think of the rough sound of the V4 to be more like a odd fire V6, a V6 design that only has 3 rod journals, that have to be shared. If this is a 90 degree block design then the firing pattern won't be even. If it's a 60 degree design, the pulses will be even. The odd fire V6 doesn't have nearly the same gaps as the V4, but the characteristics are very similar.

You can hear the roughness of the odd fire V6 here:

The big difference between an odd fire engine, and a domestic V8, is that the V8's roughness will be linear. As the engine gets louder, the roughness is still just as noticeable. With a odd fire engine, as the RPM's increase, the difference in the firing time difference decreases, and the rough nature becomes harder and harder to hear among the other engine noises. This should be easily perceived by any of you VFR owners.

If I'm completely wrong, which is possible, please let me know why. I'm 100% all ears.

Now onto other things.

As far as turbo plumbing goes, I plan to run one close to equal length header for each side, not engine. So each engine will share both turbos. I'm still undecided if I want to feed the turbos to the engines separately or together. I might feed them both into a common intercooler, and then split the air to both engines. The only reason I'd want to split them, is because designing an intake plenum that's shared might end up being HUGE depending on how far apart the engines have to be. If I can get them within 6 inches or so, then a common plenum should be doable, if not then I'll have to build a plenum for each engine, and do my best to create equal flow with balance tubes.

I hope to use the stock velocity stacks as I think they're a wonderful design for an OEM piece, and just enclosing them in a good size plenum should be sufficient.

What will be more interesting will be the intercooler/radiator setup. I'm still undecided, but there's so much room in the Z engine bay that there's no point in putting the radiator TWO FEET from the engine. Let me dig up some examples of what I've been considering as inspiration.

Here's a Z guy I really respect, known as "blueoval Z" on our message boards. He's running a small block ford.

blueoval.jpg

hoodoff002.jpg

In my case, the engine should be considerably more compact, even with the gap between them. I'm thinking I'll rake the radiator forward like he did, but set it farther back, and build a duct for it from the front, and curve the duct towards the hood, and run the intercooler as the exit for the duct, and make the intercooler a "shaker hood" type setup. This should give the intercooler decent flow and keep plumbing length to a minimum. It will also keep weight close to the wheel centerline, not way off the nose. This engine combo should be light, but I'll also be running without a transmission in the tunnel, so I'll be removing quite a bit of weight from the rear. I have to consider many aspects about the weight reduction I'll be doing in order do this right.

Oh, and I don't mind the slight offshoot topics started here. They're all interesting, and somewhat related I think. I'm enjoying it, so as long as the mods don't care, share away...

And back to the LS1 real quick. I just wanted to add that the valvetrain out there to run a pushrod V8 to 10k isn't THAT expensive, it WILL induce massive camshaft wear when compared to factory. Though if you're running those kind of RPM odds are you're ok with checking your valve clearance once a month or so. 8k is the reasonable limit for reliably, beyond that you start getting diminishing returns that will create race like wear issues.

Edited by Gollum
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I guess if you look at two VFR cranks linked end to end, they will look just like a flat plane V8, which in turn looks like an inline 4 crank with journals wide enough for two rods on each one correct?

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Exactly.

You have no clue how hard people have been looking for a 4 cylinder crank that MIGHT just MIGHT be close enough bore spacing and with wide enough journals to squeeze two con-rods onto for a cheap flat plane swap.

The reality though is that most 4 cylinders aren't even close on the bore spacing to the conventional V8 engines out there. As far as journal width, there's quite a few out there that are wide enough to "manage", but that doesn't mean I'd feel safe pushing 500+ horses through them...

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