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Viper or a 9 pound Comptech?

26 September 2000
Portland, OR
I have a four day weekend coming up, and I've decided I want to go to California to upgrade my vehicular condition. The options are:

a. Go to Comptech in Sacramento and upgrade my 6 pound supercharger to a 9 pound.

b. Fly to San Diego and buy a '93 Viper RT/10 with 40k miles and a hardtop. Drive it home to Portland, OR.

Option A, including hotel, travel, parts, and labor is about $2100. Option B, in total, is about $34,300.

I can sell the Viper for around $33,000 mid-summer, when demand for such a car is strong. With insurance, depreciation, and lost investment opportunity cost I can probably get away with $2100 out of pocket for 8 months with a Viper.

I figure the $2100 on the Comptech is gone for good. In my experience hot rodding cars, I never got my money back for my mods.

The Viper would be driven on weekends and occasionally to work when it's dry out.

It would be nice to have one, really fast and fun car to drive around all the time (NSX). It would also be nice to have a Viper for weekend joy rides. I've determined that, over time, the cost of both is roughly equal. So, as NSX owners yourselves: Given the choice, what would you do?

Red (w/ red top) '91. Comptech Supercharger. RM headers. Comptech exhaust. Short ratio gears. Ring and Pinion swap. RM racing suspension. 18/17 wheels/tires.

[This message has been edited by multisync23 (edited 07 November 2000).]
viper, its better to have some sort of diversity, not to mention u get to feel super torque any time u drive it, its just a fun car to have when u want some crazy pull in acceleration, whereas if u just get the 9 lb charger it wouldnt make a huge difference in the car compared to the prospective fun that would come out of a viper

me want NSX, me 15, me no have NSX =( but me do 3d art http://members.home.com/mcudich
Multisync... now, now.

It sounds like your money is burning a hole in your pocket.

Have you considered buying some Microsoft stock instead? (I think they are located somewhere near you.)

If you do go to Diego, don't get on an airplane in bad weather. We certainly want you to come back to us.
I think it's crazy to not fix whatever is wrong with your NSX supercharger setup. You can be $2100 out of pocket to have a Viper for 8 months and then nothing or $2100 out of pocket to have a working supercharged NSX for as long as you want to keep it.

Also, your comment about buying a Viper RT/10 and driving it from San Diego to Portland makes me wonder if you have really spent much time in a Viper before.
couldn't agree more with Lud. it will be a 4 day trip from Diego to PDX, the driving position in the viper is awkward, that huge engine / headers / exhaust causes you to sit sideways, your right leg rests against the headers (very hot)......

9 lbs for sure. you will get enjoyment out of making your NSX faster for as long as you own it - and judging from some of your past posts there could be other issues with your powerplant that Comptech can address, causing a renewed love for the NSX.

having driven both a 9lb NSX and a Viper, I would take the NSX any day of the week.
I drove a '93 RT/10. The ergonomics were awkward, definitely. It bothered me that I didn't have a dead pedal for my left foot. I didn't notice excessive heat coming from the engine, though.

I removed the Dinan chip and replaced it with a stock ECU. The difference is very significant. The power is strong from 3000 to 8000, where before I would have to wait until 5000.

I can't believe that the Dinan/Comptech set up was inspected and approved by Larry Garcia of NSX Modified in LA. You never want to advance timing when supercharging (you usually retard timing, but Comptech designed their SC for stock timing).

There is an option C:
Buy a used C5 and use the $2000 I didn't spend on the 9 lb. to buy a nitrous kit.

Red (w/ red top) '91. Comptech Supercharger. RM headers. Comptech exhaust. Short ratio gears. Ring and Pinion swap. RM racing suspension. 18/17 wheels/tires.
I dont know about you guys, but I recently had a chance to drive a '93 Viper RT/10 with 24K miles. The thing was a peice of JUNK. Granted it had more balls than just about anything I've ever driven, but aside from that, plasticky interior, rattling trim peices Cheezy removeable top, pedals that were offset funny, and a clunky truck tranny really turned me off. I dont think there's any way on EARTH you could stuff me into a Viper for a trip from San Diego all the way back to Portland. I was always a Viper fan until the day I actually got to drive one. Phew, Viper fan no more.
Keep the NSX. A well Tuned 9lb NSX should do just fine against a Viper anyways.
Multisync, first of all, if your NSX were running right, you would beat a 93 RT/10. An average driver in a new GTS runs mid 12's, an average RT/10 runs in the low 13's. Second, you can't compare the looks. While the GTS is ok, the RT/10 is, quite frankly, ugly. Finally, comfort and reliability are not strong points for any Viper. I say you'll regret going to the Dodge.
You will get tired of a 93 RT/10 in about half an hour. If you have not driven one that old, you will be amazed at how poorly they compare to the current Vipers. Aside from fit & finish issues (the early ones look like they were built in someone's basement), they handle miserably. The first couple years they built the roadsters, the suspension was a mess. Then there's the noise. The side exhaust, which WILL burn you two or three times over the life of the car. The lack of ABS. The heat. The poor seating position. The side windows. On, and on and on.

The reason the early roadsters are so affordable is that they could not hold their value when the later ones (which sucked considerably less) came out. IMHO, you should pass on the Viper.
Originally posted by multisync23:
There is an option C:
Buy a used C5 and use the $2000 I didn't spend on the 9 lb. to buy a nitrous kit.

Ok, you lost me here.

I understand you considering the Viper, it is a unique car that gives you a different experience than an NSX and is fun in its own way. People here comment all the time how it doesn't handle well, etc, yet a precision instrument or not, Vipers routinely kick NSX butt on the track. Doug / NSXFiles is one of the more accomplished NSX racers and anyone reading the NSXFiles has seen he has his hands full with Vipers and he seems to consider them a big challenge. The numbers he's mentioned some of the Vipers run at the track are several seconds faster than the best times Doug has run after many years of racing & modifications... (P.S. - I'm no Viper fan, but I'm objective enough to give the car kudos where it deserves them).

So the Viper questions are understandable. But why the heck would you now make the comment about considering a Vette?? NSXman was dead-on it seems when he said you appear to have money burning a hole in your pocket. The Vette isn't at all exotic, they're a dime a dozen, it's nowhere near as refined as an NSX, and there's no clear reason why it would have any benefits over a supercharged NSX! (It would in fact be slower).

I think you better decide just what you're trying to accomplish here, because it indeed sounds like you have some cash & are just looking to throw it at a different car.

FYI - Anyone who chooses to go down the road of serious modifications to a car (going from naturally aspirated to forced induction is a serious modification) had better be prepared that things don't always go well. More often than not modifications will uncover weak links or otherwise will give you unexpected problems. You already found one of them when you had the wrong ECU chip in your car.

Further, adding more "go fast" parts (9psi kit) onto a car that already isn't running right is a complete mistake. Your car may be running better with the stock ECU chip but it sounds like it's still not running that strong. You probably need a custom chip that retards the timing.

Get your car to Comptech and make a serious commitment to *getting what you have* working like it should be working. Add the 9psi kit when you're there if Comptech is sure your car is already running well.

Or, pull the parts off your car and sell them; either deal with getting your car tuned or stay away from modified vehicles. Don't take that the wrong way, I'm not attacking you, but in my not so humble opinion you need to evaluate your level of commitment to your modified NSX and get your car working right with the parts you have on it. Only then can you decide if you need something new.
Getting your NSX working right also happens to be your least expensive option. $1-2K to fix the NSX and enjoy it for the rest of the life of the car is way cheaper than any other option you've mentioned. Don't forget the hassles of buying and selling used cars, and the fact that you'll be paying sales tax, extra car insurance, etc.

Good luck-
I believe SpeedDemon was right on the money! If you spent the money you have marked to fix the NSX's problems then you will end up with another car and the NSX that still doesn't run right. I have been doing a lot of reading and asking questions and I don't see a huge improvement with the 9 PSI kit, I would stick with what you have and get it up to the level of performance it should be at.

I also think that you should look further for a local shop that can tune your car. There has to be additional places that have dyno's and have worked on supercharged engines. I know of a half dozen near my area, and I haven't checked very extensively. Obviouslly no one is going to know the Comptech Supercharger as well as comptech, but I am sure they would be helpful with a local shop and a good mechanic.

Good Luck with you endeavors.
I also think that you should look further for a local shop that can tune your car.

Multi, I know a few guys who use a dood in the area considered to be an expert engine tuner. He actually made the point that the SC is an unreliable way to go as it wasted about 30% power. It is actually stressing your engine much more than a properly designed turbo system. Send email if you need contact info.

Also the way your suspension gets loaded is not natural. It is too jumpy, too stiff. I wonder if you cant adjust your shocks down a bit?
The change of the ECU fixed the acceleration problem for good. It makes sense. The Dinan chip advanced my timing on an engine which needs retarded timing--with some superchargers, this can lead to detonation. The car feels 500 lbs. lighter now. I'm very satisfied with the power I get out of the engine.

I was going to cancel my appointment with Comptech, until my supercharger decided to seize up last night! I could feel the car shake at a stop light. I pulled away slowly, and as I was slowing for the next stop light the blower seized and the belt started to slip and whine. The drag on the crankshaft was so great that the car stalled.

I turned the engine over, and the supercharger freed up, but sounded like a rock tumbler. It runs fine, and I feel full boost out of it, but there's something loose tumbling around within the supercharger. It looks like I'll be going to Comptech after all.
It sounds like one of you bearings seized up and then broke loose. I am sure Comptech will take care of the problem under warranty. I am glad to here it was running right before it seized.

Good Luck at Comptech!
How old is your supercharger? I know there was a very short period in the Whipple production run when they had a manufacturing problem with the lubriction system that could lead to siezed bearings. It was a couple of years ago and they replaced all of the units for free (Whipple runs the company at a very high standard). If it turns out to be a defect in the blower itself, you should have Comptech talk to Whipple and they will probably make it right.

[This message has been edited by David (edited 09 November 2000).]
I don't know the exact age of the supercharger because I bought the car used. You're on to something, though, because it doesn't look like the current generation that Comptech offers and I remember the previous owner mentioning something about it being one of the first blowers put out.

I contacted Comptech and they suggested having the supercharger removed by an Acura dealership and shipped to Comptech. Comptech has been very helpful about the situation, and seem to imply that the supercharger will be fixed or replaced at a reasonable price (ie, not $10k).

Of course, that leaves me without a car for a while. I might need a Viper sooner than expected.

Red (w/ red top) '91. Comptech Supercharger. RM headers. Comptech exhaust. Short ratio gears. Ring and Pinion swap. RM racing suspension. 18/17 wheels/tires.
Press Comptech to talk to Whipple about it. If they won't do it, you should talk to them directly. I knew Art Whipple when I was a kid, and he is a stand up guy. If the blower is from the period when they had the bearing lubrication problem, I have no doubt they will make it right.
Hmmmm a whole car or pulley? I don't think its much of a descision, but thats me. Have you checked out the car? Is it in good condition? If its in good shape I'd say go for the viper and get the pulley later. After you get the car I'm sure you can find an extra 2100 laying around somewhere? That way you'll have both.

[This message has been edited by PUREVIL (edited 13 November 2000).]
I'm picking up a '98 Viper GTS on Thursday. Folks on this board, and even the Viper board, talked me out of buying an older RT/10 (apparently the difference between pre- and post- '96's is night and day).

I'll have to daily drive the Viper for a while until Comptech fixes/replaces the supercharger on the NSX. For anyone who's ever wondered about how a Viper works as a daily driver, I'll report on how it compares to the NSX in a week or two.

Red (w/ red top) '91. Comptech Supercharger. RM headers. Comptech exhaust. Short ratio gears. Ring and Pinion swap. RM racing suspension. 18/17 wheels/tires.

[This message has been edited by multisync23 (edited 13 November 2000).]
Thank god you passed on the early RT/10; they handle like shopping carts. While the newer ones are much more civilized (hey, guys - what if windows could go up and down!), I think you will find it a bit tiresome as a commuter if you have any traffic. It's fun for ripping around in, but is a bit of a hassle in stop & go. Also, if I remember correctly, the '98 will still get a bit toasty in the cabin at sustained low speeds. But, that may not be a bad thing this time of year. Sure is nice to have all that torque.

By the way, if you ever get bored with it, Lingenfelter is now doing Viper motors and they are much faster than the Hennessy cars.
By the way, if you ever get bored with it, Lingenfelter is now doing Viper motors and they are much faster than the Hennessy cars.

When 400+ horsepower just isn't enough...