New to Vipers Bolt on mods for Gen 4 Convertable Suspension and LSD

[LCatGA]

Probably could have picked up Gen 3 since I'm also planning to address LSD and suspension. In any case I think I got a good handle on what I should do but would love a validation from community since I'm very new to the Vipers.
Shortly about me and my goals. I hope I know how to drive and have a good experience with very high HP RWD(up to a 1000whp) cars with no traction controls. I value handling and predictability first and foremost. I like behavior of large NA engines.
Viper will be used mostly to drive around on the streets with occasional track time as I have dedicated track cars. Street manners and reasonable comfort are must for this car. So I would prefer mods which will not jeopardize drivability, meaning reasonably quiet exhaust, reasonable gearing (3.55 at most), heat control.
Here is a plan:
Headers and Exhaust: Probably Bellinger and Corsa and thermal wrap (I understand its a bit quieter)
Question - Bellinger vs American Racing Headers, Corsa vs Bellinger - how different is the sound level.
Gen V intake manifold - seems no brainer.
K&N Cold air intake - I have not found much info for it on Gen 4 - whats a consensus.
Tune - HP vs Arrow Racing PCM
Possible Gen V cams and maybe Gen V heads - not sure if they can work on Gen 4 and if it's worth $$

Short Shifter

On LSD - from what I understand Snake can be rather temperamental especially if you hit rough patch of the road. In some of my other cars I have used LSD with a great success, Guard LSD on my 996 GT2 makes 800+ RWHP in 3000lbs car with no traction control an easy and plasant ride
I also have used Wavetrac on NA street able car and Quaife on supercharged TQ monster Would be hard for me to compare them side by side now but going from memory I'm leaning towards Quaife. But would love to get community opinion for LSD on snakes for street use. OS Gilken would be too extreme and chatty

Suspension: Do not want to kill street drivability but hate body roll, Chassy twisting and non precise steering response, In fact I hate it so much what I did very custom Ohlins Clubsport setup on (sways and all) on 599 GTB and could not be happier
GT2 has 3 way Motons and full RSR spec setup and it ended up too extreme for a streets. So plan is solid bushings as long as they do not kill street drivability, Nice coilovers with Swift progressive springs and probably adjustable sway bars plus all the steering improvements available.

Top it off with mild and tasteful aero package(Rear spoiler, front spliter with strut towers and 1 set of canards (love the look) and nice audio system and snake should provide me with years of good clean fun.

What am I missing.
What I should not do.
Thanks in advance

[Aevus]

I value handling and predictability first and foremost. I like behavior of large NA engines.

We have the same tastes.

Contact the guys from TKO motorsports.

[Steve M]

First off: welcome.

Second: slow down.

What you are missing is real world data. Drive the car first, then figure out what you don't like about it. Just because you can mod certain things doesn't mean that you should. I'll expand on this later when I have a bit more free time.

[LCatGA]

Second: slow down.

What you are missing is real world data. Drive the car first, then figure out what you don't like about it. Just because you can mod certain things doesn't mean that you should. I'll expand on this later when I have a bit more free time.

Yes, I know I have to drive car and sort things out first. But knowing myself I doubt there is a stock car which will impress me in any reasonable price range. I had very limited encounters with a snake - 2017 ACR on the track back 6 years ago or so and I can tell you what I definitely can use a bit more power especially at lower RPMs, better steering feedback, a little bit less body roll at low speed tight turns and definitely more stability. Rear end was rather finicky with too much oversteer for my taste and had to be tightly controlled. It tried to step out on me a few times. I'm sure gen 4 SRT-10 roadster has even more of above-mentioned problems as compared to gen 5 ACR. This year marks 30 years of me owning high performance cars and I've yet to leave one unmolested. I know I would want more power and as precise and focused handling as I can get without ruining street drivability. I was once stupid enough to take my GT2 to the city for 20 mile and 45 minute ride. I barely could walk and I called tow truck to get me back. This car I want to be a backroad type of fun, hugging a curves of LI beaches with wind in my hair, but I would like it to be a meaningful and noticeable step up from fully moded W209 AMG 63 convertible(520 whp over 3900 lbs, Wavetrac, KW Clubsport v3 and all solid bushings, etc with underbody cross brace and strut towers braces, etc) . Something a bit more primal and less civilized, rough around edges so to say but very precise. And I believe Snake is a perfect candidate for it.

[Steve M]

Fair enough.

Out of what you listed, I'd recommend:

Headers and Exhaust: I personally like the stock manifolds, high flow cats, and stock mufflers - not obnoxious, frees up some HP, reduces cabin heat, and keeps the stuff in the engine bay a bit cooler. Stock mufflers are a straight through design - they don't cost any HP at bolt-on levels.
Gen V intake manifold - seems no brainer: agreed, if you can find one.
K&N Cold air intake - I have not found much info for it on Gen 4 - whats a consensus: as already stated in your other thread, pass.
Tune - HP vs Arrow Racing PCM: years ago, I would have recommended HPTuners. Now I'd say just go with Prefix/Arrow and call it a day.
Possible Gen V cams and maybe Gen V heads - not sure if they can work on Gen 4 and if it's worth $$: Definitely NOT worth the money. I know of one person that "upgraded" to the Gen 5 cam, and the results weren't impressive. Also keep in mind that the Gen 4/5 cams are a unique design - it is a cam-in-cam variable valve timing/phasing design (exhaust lobe only), and they are hugely expensive. Gen 5 heads may have some slight revisions, but I'd highly doubt you'd net any gains. Gen 4 heads flow plenty of air in stock form.

Short Shifter: pass, but this is personal preference. I used a shorter shift knob on the stock shifter. I has nice short throws, isn't noisy like some aftermarket shifters, and the shift effort is pretty low provided your TR-6060 is in good shape.

On LSD: this one is a slippery slope. The Gen 4/5 cars upgraded to the GKN Visco Lok, which was a substantial improvement over anything offered in the previous generations. It is well built, and most agreed it fixed a lot of the issues that earlier Gen LSDs were known for (weak internals and/or squirrely behavior). I certainly can't recommend an OS Giken, and Wavetracs are in short supply. As of last year, none were available. Likely a similar story for Quaife.

Suspension: given your experience, I can't see you being happy with anything less than what you've already had. BC Racing seems like a step in the wrong direction in terms of quality.

[Steve M]

And here's the most important part: you are buying a 15-year old car, and it will likely have 15-year old car problems.

You'll need to go over everything tip-to-tail to make sure everything is working properly. What might seem like a shitty LSD could be something as simple as the differential needing a fluid change with the correct friction modifier. You might find cracked rubber bushings, leaky shocks, torn sway bar end link boots, leaking oil cooler lines, etc. It's the nature of the beast.

And you'll also get to experience the true Viper ownership experience: lack of parts. Be wary of anything that requires you to mod stock parts in order to use them (some LSDs require mods to the stubs). Parts are getting to be incredibly hard to find. Random things like flywheels and slave cylinders have been hard, if not impossible to find. Wavetrac LSD? None to be had. OS Giken? I bought one of the last ones from Jon B. Replacement OEM stubs? Not available. 3.55s were on back order for the majority of the past year. The list could go on, but I think you get the point.

There are options out there, but you'll be scouring Ebay and talking to the Viper scrap yards for a lot of things if you need replacement parts. Factory support is non-existent for Vipers. Jon B (Parts Rack) is a good resource, as is Prefix. If you get in a pickle, Steve-Indy is a Viper national treasure. I've never asked how he knows where all the dead bodies are in Viper world, and at this point, I'm too afraid to ask. Many of us are in Steve's debt for one thing or another.

And I'm spent.

[LCatGA]

Many thanks to Steve M on a lot of info. I'm going to get MCS per his suggestion. As far as tuning, would be interesting to try messing with HP myself if I can get partner in crime
Found Gen V manifolds and Wavetrac. Still might try headers with high quality thermal wrap. Good idea about keeping stock cutback.
And yes, I fully expect to sort car out.

[Hawk]

If you are going to use this for mostly street I would also recommend keeping the stock exhaust manifolds and muffler and install HI flow cats. It will dramatically lower the cabin temp and makes the exhaust sound better. The stock has 2 cats the HI flow only 1 small one. And install the prefix PMC. These are the 2 best things for the money in my opinion.

[Aevus]

BC Racing seems like a step in the wrong direction in terms of quality.

Decent but with the Swift springs option.

[Aevus]

FYI: I might decide to sell my BC racing w/Swift springs as soon as I have the chance to test my double Penske I just had installed.

Since I modified basically everything (including the engine) here is my general advices:

- Gen 4 diff is probably very decent compared to Qaife/Wavetrac, wouldnt change it unless you track your car or is defective.
- Went from 3.07 gears to 3.73 and finally ended with 4.10. Makes the 6th really useable and a lot of fun to drive.
- Tires. Not many options track/street, so I decided to go Kumho ACR 355s on the rear and A052 295s on front. Otherwise, stick with Michelin if possible.
- Bought a lot of goodies from TKO motorsports and my favorite is the bump steer correction kit. Shouldve install this on day 1.
- Alignment: Lots of front caster. Got +8.8 at the moment, while keeping -1.1-1.2 camber. Great for street, for the track it would be better to have more camber of course.
- Headers-exhaust-cats... Be cautious, sound changes very quickly and not alway in the right direction. In regards of performance, it's very costly for not so much gain (unless you modifiy the engine) big roar is deceptive, maybe you're not going really faster ;-)

[J TNT]

If you need a Gen 5 intake manifold pm me , I did swain coatings for headers waiting to get them back in 5 weeks . They are in your State , Rochester . Others have had good luck with them .

Many thanks to Steve M on a lot of info. I'm going to get MCS per his suggestion. As far as tuning, would be interesting to try messing with HP myself if I can get partner in crime
Found Gen V manifolds and Wavetrac. Still might try headers with high quality thermal wrap. Good idea about keeping stock cutback.
And yes, I fully expect to sort car out.

[Aevus]

Just found my mods list:

M&M 3'' race headers - Heat wrapped basalt fiber
Magnaflow high-flow 200 cel cats
Custom 3.5'' exhaust (to be re-modified, too loud w/ new engine)
Centerforce dual friction clutch + slave & master cylinders
Fidenza lightweight flywheel


Competition Coupe swing arm oil pan
HPS Red color silicone hose radiator
ECU program gas 94oct + Rev limiter 7100rpm + (for race rebuilt engine w/23 deg overlap cam)
Camshaft custom 246/256 LSA 114
Mahle forged pistons 4032 alloy
Callies forged connecting rods
Injectors 69 lbs
Ported gen 3 heads (flow numbers similar to gen 4's)
Compression 10.9:1
Machined + (over)balanced crankshaft for 7,200-ish rpm
Conical valvesprings 0.615'' lift Compecam
Titanium valve retainers Compecam
Ferrea stainless steel competition valves
Performance Prefix lightweight hydraulic lifters ceramic 1/8 zero-lash
Push rods 3/8'' w/ 0.080'' wall
Prefix oil pump rotor oversized
K&N intake & air filter kit
BBK 67mm throttle body
Under Drive Crank Pulley

Limited Slip Differential (Wavetrac)
4.10 final gears

Khumo 720 ACR 355-30-19
Yokohama A052 295-35-18 (to be changed soon)

TKO bump-steer correction kit
TKO control arm bushing kit
TKO adjustable sway bar links
TKO rear shock mounts spherical bearing
(4th trial) Alignement: Camber F -1.45 :: R -1.0 :: Front Caster 8.8 :: Toe total :: F +0,10deg :: R -0,50deg
IPS Solid Steering Rack Bushings
ACR (solid) sway bars Front # 05181444AA
ACR (solid) sway bars Rear # 5181438AA
Upgraded IPS Sway bar bushings
Corner balanced
Race Poly engine mount
Race Poly transmission mount
Short Throw Shifter
Race front brake pads Hawk HB193S.670
Penske double coilovers
HYPERCO springs 13.4kg/mm (750lbs) front + 17kg/mm (950lbs) rear

----------

Don't care much about dyno numbers but I'll be happy with a trap speed of 135mph and I secretely wish for 140mph (4.10 gears + rev limiter was meant for that goal).

Will not track the car even though it's basically a track car now... After a problem-free 10 years with Porsches on the track, I blew a Viper engine within 3 laps... Have trust issues since then. But hey, maybe I won't be able to resist the urge one day...

Basically the car feels MUCH MUCH better than stock-ish (bought it with BC coilovers and slightly modified exhaust). I most certainly could not enjoy a stock Viper anymore, probably not even a gen 5... but then again I like my sportcars very raw and brutal yet predictable, which is now.

Engine installed but not tuned yet:
https://www.youtube.com/watch?v=EzaxOlgPFj4

I did not regret any modifications (as of yet) but I might have been too optimistic with the camshaft, it may be more difficult to tune than expected, will see.
Also that headers-exhaust system was perfectly fine with my other (stock) engine but that new high compression/big cam engine makes it absolutely impossible to drive on the street: I would be pulled over the minute I hit the road... it's crazy loud. Wish I'll be able to find a solution for that too.


Bottomline: the only possible ''upgrade'' to that beast would be a Cayman GT4 RS for a ''decent price'' or a GT3RS or Mclaren 765LT if I ever go crazy. But since I have trust issues with Mclaren in general -witnessed 0 owners that finished a lapping day without issues- I probably will go back with Porsche for any serious track use.

Problem is: I will probably miss the rawness of my Viper.

[awhit17]

One LSD to look into that has little data but I bet would work great is a Drexler. They’re very popular with the Euro crowd and supply a lot of Motorsport applications. They have a Viper application that’s worth looking at.

[LCatGA]

Drexler is a clutch based just like OS Gilken, and both are a not a best choice for a street cars

[awhit17]

I disagree. I assume you’re saying that because of the clunking that can sometimes happen. For a clutch based diff, it’s typically all about how you set it up. The Drexler diffs tend to work well with very low initial torque, sometimes 0 which means they’re essentially silent on the street as long as you set them up that way. You can do the same with an OS-G although I’ve heard their setup out of the box for the Viper is a touch more aggressive than other models.

But to your point if it’s only a street car a clutch style diff may be more than you need.

[pokeyl]

Wavetrac, 3.73 gears, Dyno 621 WHP---600+ Tq, hooks true in a straight line, and puts the power down out of curves. I don't understand how, it just works!
2 years running and many event, 3K total miles, Zero faults.

[LCatGA]

Wavetrac, 3.73 gears, Dyno 621 WHP---600+ Tq, hooks true in a straight line, and puts the power down out of curves. I don't understand how, it just works!
2 years running and many event, 3K total miles, Zero faults.

What modes do you have tk get that whp?

[pokeyl]

Gen 3 motor
Heads port-
cam ROE 710r, Springs, Push Rods, Lifters
exhaust MOPAR race
tune Custom 93
I am running stock pistons with Gen 4 head gaskets and .030 off the heads. 10:1 CR could be 10.5:1. Did not do the math. Sorry

[Hawk]

If you need a Gen 5 intake manifold pm me , I did swain coatings for headers waiting to get them back in 5 weeks . They are in your State , Rochester . Others have had good luck with them .

I did the Swain coating with my Belanger headers, It helped reduce the heat in the engine compartment however it pushed the heat lower into the exhaust and caused problems for heat build up at the cats. In the end I had to wrap the headers and collector pipes as well as get rid of the Cats and add additional insulation to my side sills. I do use my car mostly on the track so on the street it may be fine, I had a bitch of a time I hope your experience is better. Good luck if you try calling Lew B.

https://driveviper.com/forums/thread...ng-for-headers
https://driveviper.com/forums/thread...heat-wrap-help

[LCatGA]

Plan to wrap whole exaust.

[J TNT]

Thanks for the heads up Hawk , I chatted with several members who are running 9 liters and Prefix. You make an interesting point on moving the heat elsewhere. I may leave the J pipe uncoated to save the cats. My biggest concern is the wiring and will take precautions.
I did chat with Lou , he was interesting.

I did the Swain coating with my Belanger headers, It helped reduce the heat in the engine compartment however it pushed the heat lower into the exhaust and caused problems for heat build up at the cats. In the end I had to wrap the headers and collector pipes as well as get rid of the Cats and add additional insulation to my side sills. I do use my car mostly on the track so on the street it may be fine, I had a bitch of a time I hope your experience is better. Good luck if you try calling Lew B.

https://driveviper.com/forums/thread...ng-for-headers
https://driveviper.com/forums/thread...heat-wrap-help

[Hawk]

Thanks for the heads up Hawk , I chatted with several members who are running 9 liters and Prefix. You make an interesting point on moving the heat elsewhere. I may leave the J pipe uncoated to save the cats. My biggest concern is the wiring and will take precautions.
I did chat with Lou , he was interesting.

If you have any questions when you get into it or want some pictures of what I did feel free to PM me and I can try and help you out
Dennis

[white out]

What am I missing.
What I should not do.
Thanks in advance

Headers: like mentioned above, greatly increase and change the sound. But also create a significant amount of power.
ARH is a 5-1 design similar to the ACR-X header.
Bellinger has a restrictive pickle in the collector - go M&M if you want a 5-3/2-1 (tri-Y) header.

Exhaust:
Borla & Corsa are popular options and reasonably priced.
If you are not set on any brand, it is fairly simple to make an exhaust for a GEN4.

Intake:
Decent gains (K&N advertises 18whp) but it improves throttle response and works with other bolt ons for better gains throughout the powerband. It will also increase the engine acoustics on the intake side. But it is not cheap.
Drop in filter & smooth tubes are a good option for more power, but usually require a tune.

Short Shifter:
IPSCO short throw shifter with 2" shifter ball lowering kit

Suspension:
Coilover options:
--BC coilovers (with or w/o Swift springs)
--KW V2 coilovers
--Penske coilovers
Solid steering rack bushings