Would this be insane? *rhetorical question*

[racetech]

Would this be insane? *I realize this is a rhetorical question*

As I read about people questioning if there may be hidden NOS systems on some fast Vipers & other cars, I'm reminded of why I don't care for power adders in general. Please understand, this is just a personal opinion and I do admire the work done by many installing S/C, T/C, and NOS systems.

About two years ago while conducting a racing engine school, one of our instructors (and world-famous racers) made what I thought was a great point in response to a question about nitrous oxide systems. Here's what he said: *paraphrasing*

The problem I have with nitrous oxide systems is that they kind of make all the hard work you do on an engine a "so what?". Sure, you worked really hard getting things right in the short block. You may have a great pair of cylinder heads and a killer induction system. Yes, your car is really fast, but if you also have a bottle, people will look under the hood and say "Oh...well, no wonder--it has nitrous". It kind of negates all your hard work because everybody knows a shot will add power, and up to a point, more will keep adding more.

I agree with him and don't care for the idea that when your bottle is empty, you're out of power.

I'm going to say some possibly upsetting things, but please don't kill the messenger! I'm as rabid a Viper fan as there is I think, but...to be honest, the Viper engine is 30 year old technology. Don't feel bad--most "high performance" engines that you see in cars started life decades ago in engineering departments.

I took a look at the "high performance" heads that are available for the Viper engines and well...what can I say. Yes, I know they can represent a bolt-on gain of 50hp--nothing to sneeze at. But...so much more is possible. They are not only 30 year old technology, but they have other problems that would be nearly impossible to fix.

I'm telling the truth here, but many will find this absurd--ridiculous--impossible. The folks I deal with work mostly with naturally aspirated racing engines and routinely create up to 2.65hp/CID. Their best so far is 2.7hp/CID. I watched them test a 358 cubic inch Pro Stock Truck engine. With two carburetors and on nothing but racing gasoline, it hit 960hp at just under 10,000 rpms. Bill Jenkins stuff was a little better...probably right around 965 hp. Not bad for pushrod engines!

On a bad day, these people make 2.5hp/CID. That'd be a naturally aspirated 1220 hp Viper engine, presuming they could solve the problems assoicated with an aluminum block and a very long V10 crankshaft. On a terrible day, they could make 2.0hp/CID. That's still a 976 hp 488 engine. If they really tried hard to screw everything up on a streetable engine, I'm sure they'd still make around 1.7hp/CID and you'd have an 830hp Viper engine.

But...it would take fixing what's really wrong. It would take a total redesign of the heads, valve train, camshaft, pistons, rods, and induction system.

I was at the PRI show recently in Indy and well, the pieces have all fallen into place for me to put together such a package, starting with new head castings. But the costs would be very high, and I'm not sure I'm THAT insane. I know there may only be a market for a few hundred sets of the heads.

So here are my questions. How much would you pay for such mods? And would it still be a Viper engine? Afterall, the only "Viper" parts left would be the engine block and accessory items. For a moment, indulge me and presume that I could hook you up with a naturally aspirated Viper engine that would have about 800-850 hp with no power adders. Increase the displacement and you'd have a hundred more. Add power adders and you're way over 1000hp. What's that worth to you?

Thanks for your input...

Bob

 

[BIGBADCJ]

how long do you think one of those motors would last? why when you can stick with a stock everyday driver motor and just spray the hell out of it. it lasts longer and it a hell of alot cheaper. i say just keep extra bottles and you will never be out of power.

 

[Shelby3]

Turbo's and blowers already make insane almost unusable power in the Viper and they don't run out of bottle. I think you're right about the market being small for your approach.

 

[Gerald]

Problem with N/A motors once you start really getting pushing the limits of the motor, the car is beating itself to death even at idle.. Blowers and Turbo's don't sacrafic very much if anything on the life of the engine. I can't imgaine having a 850RWHP N/A viper and putting 20,30,40,50k daily driver miles on it..?

I'm sure there's a market out there, but how much is a good question

Gerald

 

[cratica]

You raise some good points, but the bottom line is reliability.

Sure, you can create massive horsepower n/a but for how long?

I'm an avid Nascar fan and used to have a nascar license as well as a street stock race car (beginner class). Nascar Winston cup engines can put out 800 hp out of a 350 ci/class V8 and that's with quite a few restrictions. The engines are capable of even higher hp. Thing is, even with the 'lower output' of ONLY 800 hp, many of these engines don't even last 1 race (300-500 miles). Also, you have to realize these race teams are using the best components known to man and spare no cost in engine building/development.

So, yes, you can get a LOT of hp out of these engines, but the real talent is finding the best compromise between reliablilty/longevity and horsepower/performance. It's relatively easy to do one or the other, only experience and talent can do both.

 

[joe117]

I've always thought the Viper V10 was put in there just to make the car exotic.
It's a good engine. Its state of tune is about the same as the LT4 Vette engines. It could easily be better.

The problem is, it's a low production engine with very little aftermarket speed equipment available for it. And what is available is very expensive.

There hasn't been 1% of the R&D done to the V10 that has been done to make power from other American engines.

Getting lots of power NA has some trade offs too. Without some kind of variable valve timing there is going to be a problem with low end power and street driveability.

If I wanted to make a Viper go fast with a NA engine, I'd have to say that I wouldn't use a Viper engine.

I would probably use a sb aluminum chevy bored and stroked to max displacement. Taking advantage of all the high tech equipment available, I'd expect over 2hp/inch and with super rods and crank it would be bullet proof.

Someone could re invent the wheel and spend a literal fortune on the V10 to max it out and make that kind of power NA but I don't believe anyone is ever going to make a super NA V10 that any car guy would buy. There just are not enough of these engines out there and thus the price would put it out of reach for all but a handfull of owners.

Of course, it wouldn't be a Viper and there probably are a handful of guys who would go for custom cast heads for the V10.
Like you say, the cost would be huge.

I can't imagine getting the kind of flow from newly cast Viper heads that is available from quality chevy aftermarket heads. People have been working on that for decades. Can you beat them on your first try?

 

[SNKEBIT]

You raise some good points, but the bottom line is reliability.

Sure, you can create massive horsepower n/a but for how long?

I'm an avid Nascar fan and used to have a nascar license as well as a street stock race car (beginner class). Nascar Winston cup engines can put out 800 hp out of a 350 ci/class V8 and that's with quite a few restrictions. The engines are capable of even higher hp. Thing is, even with the 'lower output' of ONLY 800 hp, many of these engines don't even last 1 race (300-500 miles). Also, you have to realize these race teams are using the best components known to man and spare no cost in engine building/development.

So, yes, you can get a LOT of hp out of these engines, but the real talent is finding the best compromise between reliablilty/longevity and horsepower/performance. It's relatively easy to do one or the other, only experience and talent can do both.

I agree, sh1tloads of power can be done but how long is it gonna last??????
Look at fuelers, they're lucky to get a 1/4 mile!!!!

 

[racetech]

I can't imagine getting the kind of flow from newly cast Viper heads that is available from quality chevy aftermarket heads. People have been working on that for decades. Can you beat them on your first try?

I've always been a firm believer that the aluminum really doesn't know if it has a bowtie, oval, penta-star, or other insignia on it. The reason they'd flow just as well is because they would have the same valve layout and chamber design as other state-of-the-art heads. More than likely, they'd flow better because of the skills of the guy (friend) I've talked to about doing this. His stuff is on quite a number of the fastest cars in NASCAR and drag racing.

The reality of professional-category racing today is that everyone has been driven to essentially the same point--canted valves, tiny heart-shaped combustion chambers, flat-top pistons, spark plug located as close as possible to the center. That works and everything else falls short.

The cylinder heads in racing today are far more similar than most would believe. Example? The people I work with run exactly the same CNC port program on both their "GM" and "Ford" Pro Stock heads. Now THAT's close! The "Hemi"? Sorry. Great marketing ploy, but look at the Pro Stock Chrysler "Hemi" heads. Same canted valve w/small heart-shaped combustion chambers (twisted slightly from the GM stuff). Finished race-ready versions have around 47 cc chambers. That's right...FAR smaller than even the earlier (pre SB-2) small block Chevies.

The posts here about longevity are basically correct. However, I think they tend to overlook the fact that, ultimately, the only thing making more horsepower is greater cylinder pressures. Regardless of how you achieve this, the longevity at WOT will suffer, and suffer similarly. Adding nitrous oxide can be particularly tricky--if you don't add the right amount of fuel, it's goodbye pistons and you might want to have a fire extinguisher at the ready.

So...the longevity would still be related largely to hp being utilized. Winston Cup engines run all day at 8800rpms and mostly at WOT (wide open throttle). That represents years of hard service for most engines. As you drive around everyday, a naturally aspirated 800+hp Viper engine would "coast", only delivering the power needed to overcome parasitic losses and wind resistance.

Give it WOT and high rpm's and it's of course another story. No pain, no gain. All in all, I can't believe that a naturally aspirated engine that is mostly run in lower rpm ranges would be worse off than other supercharged or turbo systems. An argument can be made that natural aspiration has advantages of cooler intake temperatures and fewer moving parts. Now, put your power adders on this baby and...you have even-more-insane amounts of power. But, aren't they coming out with "supercars" that have 1100+hp anyway like the Bugatti?

The biggest problem I'd run into is, I think, getting it "right" the first time. R&D can easily become a black hole for money and time. That's why I'd only do this in conjunction with people who make low-production racing heads all the time. Even then, I've had nightmares of burned up rocker arms, broken lifters, hot spots in combustion chambers, and all the resulting redesigns.

Yep...I'd have to be insane to try this, but then...life is short. I'm still thinking!

Bob

 

[joe117]

So the up to date chevy/ford high flow head design can be brought right over to the V10.
I didn't think of it that way, you're probably right.

So what's a ballpark price per set if the production run was 500 sets? That number would go a long way in predicting the marketability of your idea.

The other number would be the hp gain from the new heads, cam and pistons?

By the way,
I'm glad to hear what you said about the hemi.
I've been saying that the new Hemi is all about marketing and nothing more.
A bunch of guys on the board told me I was full of it when I said that a couple of months ago.

 

[Lee00blacksilverGTS]

I'll keep my 30 year old technology thank you. I've been through so many "grenade" motors in both cars and more expensively in offshore boats that I could just not care anymore. I want what gerald referred to....massive power that does not beat the engine to death. And by the way, the Viper engine was an all new design with lots of the development done by Lamborghini when it was first brought out. It is not a rebopped truck engine as many think. But I suspect what you were referring to was the state of the art in standard v8/v10 development as having originated in the 50s actually, right?

 

[joe117]

I'd call the Viper V10 a little better than 30 year old technology.
The roller cam, aluminum heads/block and EFI are the things that make it different from 30 year old technology.
Not much else.
Like I said, it's very much like a LT4 with 2 extra holes.
Of course, there was no LT4 in 92.

 

[Vipermed 97.01]

Actually upon conception of the viper motor was BoB Lutz and Carrol Shelby debating the 10 vs 8 cyl. issue.Bob wanted 10 and shelby wanted 8.......Bob won....but what where the irony is the Lutz is now spearheading GMs V-8 as the soon to be "viper killer"

 

[RX VIPER]

Bob,

Per dollar for what current venders have to offer, for 800rwph it would be in the 18-23k range. IMO.

-M

 

[Paolo Castellano]

Racetech,

Rhetorically speaking, I would say you should go for it and make a head that flows 340-350 CFM that has better cooling properties/etc.....

I know that your 500 sets of heads would be gone very quickly because even the 'regular' motors could benefit from such a flow capacity.

While you are at it maybe even make a dual overhead cam head. That would be fantastic! Every single type of application could benefit.

I know the Nascar motors are rebuilt after every race. Nobody here would be interested in anything maked out like that.

RPM's kill a motor faster than anything else. I am sure with the proper clearances and design, even a 1.7-2.0 HP/liter could live a while.

P.S. When you get a set of those heads done, let me know, get a set to Jason Heffner and I will test them for you!

 

[Torquemonster]

There's some comments in there that a thinking person would do well to take notes and learn.... excellent points Racetech whether this idea goes anywhere or not - thanks for sharing!

I've had a guy offer to build me a set of 40V heads for the Viper that would really wake it up... his V8 32V heads are making big power with excellent drivability - as all good 4V motors tend to do. The 4V is worth far more than multi cams.

A 10,000rpm V10 would be a challenge to keep it alive, but a 7-8000rpm V10 would be a cake walk - something a guy like you could design basic specs for on a sheet of paper over a coffee. I've known since joining the forum that the Viper engine has been way under developed - it'd be great to see progress in this area - especially with the advent of twin turbo's coming on now - if we only had AWD to harness it the limits would be mind bending.

The die hards will stick to what they know - but you are not the only one out there thinking and good thoughts deserve each other... hope you'll stick around.

 

[racetech]

The "30-year old technology" is basically a reference to the combustion chamber/valve configuration and the traditional pushrod design. It looks to me very much like the old "closed chamber" BBC heads--valves shrouded rather deeply into oval pockets. Also, the all-important venturi area just above the valve seats is...um...er...could use improvement. Material needs to be put in there and shaped properly, but the thin-wall castings, re-heat treating, and machining would make all this cost prohibitive.

Here's a serious problem...suppose I have these head manufactured. They'll require different components like pistons, so it would never be a bolt-on piece. You'd need the whole package, or nothing. I see this problem ALL the time--what I call the Beta/VHS problem. Beta was a vastly superior video tape format, but VHS had too strong a foothold on the market.

Chevrolet screwed up badly (it just wasn't realized at the time) with their "open chamber" design BBC. The required piston dome really gets in the way of flame propogation and that's why those things need 40+ degrees of spark advance.

But...head manufacturers need to sell product and that means "bolt on" pieces that fit existing short blocks and pistons. Piston manufacturers aren't about to make a new design for which there is no head. So, round & round we go stuck with that huge BBC chamber and Mt. Everest dome. *finally, the tide is turning however...Dart, Brodix and others are creating state of the art high-flow pieces with small chambers*

Not to get too technical here, but spark lead is your enemy--it creates cylinder pressure as the piston is going up prior to the power stroke and drags away power. The big "secret" I think is out now enough to tell you that the hemi is even worse for gasoline & N/A applications. Those things often needed more than one spark plug per cylinder and I know some guys that run about 50° BTDC. Bob Glidden's Ford "hemis" had combustion chambers filled with tons of aluminum TIG weld to make them work. Modern racing engines run about 23° (or less) spark timing--a great indicator of combustion efficiency.

High rpm's creates a really serious durability issue. You need them to be as high as possible because HP=torquexrpm's divided by 5252. The racers I work with have not created any extra torque in over 10 years! What they have done is moved that up about 1,000 rpm's, thus the much higher hp numbers. Problem is...speed kills. Kinetic Energy=MV²/2. That means that when you double the velocity of something, the force goes up by 4 (the square). Triple the velocity and it goes up by 8. Ouch. So...I figure these engines would redline about 7200 rpms, a realistic goal for an engine that could survive. The racers I deal with zing the 358 SB2 engines to 11,000 (with pushrods!), so 7200 seems doable.

There are so many "old school" rules around that cloud other durability issues--like valve spring tension. The more spring tension you run (to a point) with roller tappets, the longer the valve train lasts (some readers are now coming unglued, I think). What tears up valve trains is lash. Give the parts a running start at each other and everything gets really beat up. High tension springs do not create hardly any additional turning friction (just as many lifters are going down on lobes as up), but high tension springs get hotter in operation and require more oil spray to keep them cool. Roller cam bearings are a must here.

Yes, it's absolutely true that going to 3 or 4-valve per cylinder layouts, OHC, or variable valve timing would help too, but you have to draw a $ line somewhere. There is SO much engineering info around for the "30 year old" pushrod engines that there would be considerable economy in maintaining that configuration. I think...lol

Thanks for the kind comments and insightful posts here. I'm always impressed by the knowledge of the Viper people.

Bob