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omg that black one is incredible looking... WANT THAT.....

viper engine in an MR2 though... would be pretty neat...

though it would basically be a henessy venom...
 

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Gouky said:
The 8.4 liter motors are 600hp
that's still quite pathetic when you look at it in terms of power per displacement. but yeah, 600hp is nothing to laugh at either.[/QUOTE]
People have to stop thinking specific out as in hp/liter. It isn't always the hp/liter that makes an engine badass or not. There aren't many engines out there that make the brutal torque that an 8.4 liter V10 does. The Viper is intended to be a brutal car. Yes it has gotten some finesse over the years, but it is about as brutal as a car can be in modern times. Not many cars that can hang with a Viper either. The 2013 Viper engine is still 8.4 liters, but has been bumped to 640 hp and 600 lb/ft torque. Might not be a finesse engine, but it is about as effective as a 20 lb sledge hammer making mashed potatoes.
 

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scottgas said:
People have to stop thinking specific out as in hp/liter. It isn't always the hp/liter that makes an engine badass or not.
i'm not doubting it's worth as a motor. it's just not an achievement like many other modern motors are.

certainly it still has it's pedestal. and if you're going for the full aural experience nothing else can sound like 8.4L. heck, that radial engine i have only puts out 160hp, but it does it with 8.9L and it sounds so great doing it.
 

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Gouky said:
i'm not doubting it's worth as a motor. it's just not an achievement like many other modern motors are.

certainly it still has it's pedestal. and if you're going for the full aural experience nothing else can sound like 8.4L. heck, that radial engine i have only puts out 160hp, but it does it with 8.9L and it sounds so great doing it.
except for UPS trucks.
 

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Gouky said:
i'm not doubting it's worth as a motor. it's just not an achievement like many other modern motors are.

certainly it still has it's pedestal. and if you're going for the full aural experience nothing else can sound like 8.4L. heck, that radial engine i have only puts out 160hp, but it does it with 8.9L and it sounds so great doing it.
Gouky, I wasn't necessarily talking about you. Just seems like so many of the younger members here worry too much about hp/liter. Yes, I agree the Viper 8.4 liter has a low specific out, but like I mentioned earlier the Viper was not meant to be a high winding Ferrari competitor. I was meant to be a car that bludgeons its competitors into submission which it does quite well. The newest Viper engines are absolute monsters. This coming from a huge Corvette fan. I am not much of a Viper fan, just giving credit where credit is due.
 

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hp / liter is an internet penis length comparison figure. hp / weight is the number worth getting excited about. Motor swaps where you remove an iron block and add an aluminum block with more displacement and power with less weight to result in better fuel economy and acceleration... win win win. Swapping a massive heavy motor + required transmission adding significant weight requires more tradeoffs to decide if it is a win or not.. If you add 500+ lb total weight to the car, have to remove the trunk, have to stretch the chasis, have to move the center off mass backwards farther as there is more hanging into the trunk area behind the read axle line, have to improve the brakes not just for the added power, but for the added mass as well, have to adjust suspension significantly to compensate for the completely different dynamics of the car, maybe have to strengthen the chasis itself as you are more than tripling the torque delivered to the wheels.. etc etc.. At some point you think, just owning a viper would be cheaper and have better results, especially if you do not have the resources to just go measure the peg and the hole and decide if they will fit without asking on an internet forum. I have to confess, I thought the original poster was a troll baiting us.. I am very suprised to see so much serious discussion in this thread when there are so many other options that would work much better with many fewer tradeoffs.
 

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you bring a very interesting point in the HP/weight.

i just looked up the V10 and the first number i came across was 711lbs. that's massive, like big heavy diesel motor heavy.
 

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Gouky said:
you bring a very interesting point in the HP/weight.

i just looked up the V10 and the first number i came across was 711lbs. that's massive, like big heavy diesel motor heavy.
Like Jared posted after you, the new Viper engines are considerably lighter than early ones.
Also, there is more to power/weight than just hp/weight. There are 500hp Honda motors that won't pull crap against a 500hp LS7 or Viper V10. There is more to power than just hp. If you look at what an 8.4 liter V10 is capable of power wise even in n/a form, it makes a pretty strong argument for itself. The Viper V10, at least rev 2 motors, are capable of being punched out to 9.0 liters. Depending on what your project is, a punched out Viper motor would make one hell of a beast of a motor.
Even LS7s are capable of 600hp without that much work to a stock one.

Sorry for the ranting but my point is that these big motors not only make big hp, but BIG torque.
 

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another big factor is the power curves... if you imagine a dyno graph for example... the viper engine will have that power at a much lower and build that power much faster in the RPM's thus making the vehicle it is in, faster in a shorter amount of time, or a shorter length of road...

you gotta remember, the HP an engine has is what its peak horsepower is at its optimum range. same goes with torque... now how that hp/tq gains and falls and when they gain and fall can create a VERY different performing powertrain
 

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scottgas said:
Like Jared posted after you, the new Viper engines are considerably lighter than early ones.
Also, there is more to power/weight than just hp/weight. There are 500hp Honda motors that won't pull crap against a 500hp LS7 or Viper V10. There is more to power than just hp. If you look at what an 8.4 liter V10 is capable of power wise even in n/a form, it makes a pretty strong argument for itself. The Viper V10, at least rev 2 motors, are capable of being punched out to 9.0 liters. Depending on what your project is, a punched out Viper motor would make one hell of a beast of a motor.
Even LS7s are capable of 600hp without that much work to a stock one.

Sorry for the ranting but my point is that these big motors not only make big hp, but BIG torque.
yes and no. the torque number simply does not matter. what matters is the area under the HP curve that has to be used based on the transmission in the vehicle.

the reason this myth persists is because bigger displacement cars (high torque cars) tend to have a much flatter HP curve. this means you're putting down higher HP numbers most of the time.

acceleration is only affected by how much HP is put to the ground at that instant. torque is not the full answer.

if we take my favorite example, the 2gr has a terrible HP curve.


it feels like the thing is launching you from a slingshot every time you hit the top of the RPM band. feels awesome until you realize it's awesome in the way v-tech is. if the power delivery was smoother you'd be faster.

if you look at a more traditional dyno curve from a bigger engine:


the torque curve drops in the area that you use while driving in anger. but the HP is fairly flat so it feels like smooth power delivery and overall it puts down more power for the same HP number as the 2gr delivery above.
 

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I agree with Gouky and Jared. The 2gr is probably what would be considered a "high performance" engine destined to be trapped in pedestrian cars. I think it is also needing more revs. It looks like it would just keep making power. The 2gr is also still a relatively small engine comparatively speaking. So of course to make big hp it will need to rev. I am not an expert at reading dyno graph by any means, but it looks like it builds a decent amount of down low, then builds strong hp as it revs. It seems to look like a pretty balanced engine hp/torque wise. A lot of people look at engines like the Viper V10 and the LS7 as big torque monsters. More so the V10. I believe the new ones rev to 6000 or maybe more and do make more hp than torque. They are just so big that they make huge amounts o both. The LS7 revs to 7000 and makes lots of both, just not as brutal as the V10. The thing with both is that they both CAN make lots more hp and torque with very little work. Turning both engines from mere beasts into absolute monsters. They still aren't necessarily the right engine for every project. To me, the engine needs to fit the personality of the car. I think a high revving V6 or turbo 4cyl fit the personality of an MR2 better than a big V8 does. Sorry for tha rambling.
 

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I've already done this....it's overated. Its too heavy and makes the car plow, plus it sounds like a bag of marbles.

Honestly what is the point?
 

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Seriously, my Norwegian friend, the Viper engine is a dog... a very heavy dog with not much power.

IF you are serious about V8 or V10 then i would strongly consider some of these for donors.....


* Toyota/Lexus LS430 - 4.3 V8 ~300hp+ (plenty of mods available for 800hp builds)
* Audi RS4 B8 - 4.2 V8 ~420hp (difficult to modify)
* BMW M3 - 4.0 V8 ~420hp
* BMW M5 - 5.0 V8 ~510hp
* Audi RS6 - 5.2 V10 TT ~575hp (hens teeth to find)

All of those engines are at least 6" shorter than the Viper block AND a good 300lb lighter. Modern all alloy engines are far better for this sort of thing because the last thing you want to do is bog down all that power with stupid weight!

If it had to be V10 then i would not consider anything other than the BMW V10. widely regarded as the best V10 out there. Does a pretty ok job of getting an unsrestricted M5 to 200mph.....

As for transmission.... Tricky once you get to that size and torque you are asking a lot of something from a normal car... I would still probably say the Audi 2.5/2.7 TDi 6-speed from 00-05 roughly. Very heavily build gearbox designed for diesel torque. Ok on an M5 Engine you may lunch it a couple of times but there are gear firms out there that will build it up to take big power too. It's only a case of hardened or straight cut gears in most cases...

HTH

711lb!!!!!! My God!!!! Don't fancy building an engine stand for that! :D
 

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Kotaru said:
So I take it you've owned/driven one or is that just an opinion based on conjecture?
Conjecture Kotaru. I've driven every Audi up to 2006 to wear the S/RS badge and most of the BMW M's amongst others.... Have a passenger ride in a Viper and there is no doubting it is a brutally quick car. But adding a 711lb anchor to the SW20 chassis will not do it one bit of good... The weight would jump to 3200lb roughly! stops being nimble at that stage. My dog comment is in terms of weight... not to mention it's based on a truck engine..!
 

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400lbs compared to the power and especially the torque curves that the viper v10 has.... i think everyone needs to stop kidding themselves... if someone did this the car would be friggin nuts... plain and simple...
 

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but having seen a viper engine bay, and worked on all 3 mr2 generations - the cutting and reinforcements that would be needed just do not make sense. You have to do so much work that you might as well choose a better option, especially if better options end up with a total power to weight ratio that is better.
 
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