Tko Bump steer kit install

[Tamvette]

I am in the process of installing this and noticed the factory spacers are not plastic and thicker than what TKO has seen with other cars. Has anyone seen this?

Would you match the factory thickness by adding some of the factory shims on top of TKO spacer or just use the TKO spacer?

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[Tamvette]

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[sharmut]

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The isolator(part# 4642116) on the frame side looks cracked.
There's an o-ring(item# 4, part# 4708035AB) that sits between the isolator and steering rack.

[TKO MOTORSPORTS TEAM]

cracking ( aka: gassing out) is normal on most rubber( buna-n, nitrile, EPDM etc) parts especially on the east coast with salt on the roads and dry climates like the south west and high desert are especially hard on rubber parts. You just keep an eye on them and replace or upgrade as needed. Another reason we use anodized aluminum rack spacer in our bump steer kits.

[Tamvette]

The isolator(part# 4642116) on the frame side looks cracked.
There's an o-ring(item# 4, part# 4708035AB) that sits between the isolator and steering rack.

Thank you for the heads up. It looks worse in picture than how it looked in person. My control arm bushings looked in much worse shape which I did change. However, this could be a maintenance item next time I take things apart.

[texasram]

I was interested in this kit. Subscribed*

[Tamvette]

Wanted to post a quick update here, I finally got around to install rest of stuff including tko sway bar endlinks, rear toe link, dse delrin control arm bushings and tranny mount.

Took the car for alignment, and we did a bump steer plot to make sure things looked right with tko spacer only installed. If we measured things right with the gauge, we saw about 0.0048" toe out per inch of suspension travel. I couldn't find any guidance on what exactly we should be shooting for other than making sure it is toe out with suspension travel. If anyone has any more insight, please let me know. Next will be track test.

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[Tamvette]

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[SLP]

When I contacted TKO about the install, they said that they see 03-.08” variance in bumpsteer after install with no CW/bump adjustment. I opted to forego a bumpsteer alignment because of that at the time. The kit alone and a standard TA alignment made a huge difference. No more bumpsteer issues on the track.

[GTS Dean]

I don't know about later Gens, but the G2 manual warns against more than 3/8" total stack thickness under each rack mount. I would assume all are similar.

I think the TKO kit trades the shim stack with a constant thickness spacer, and moves the adjustment to the outer tie rod end height.

You should be measuring either degrees of toe per wheel, or decimal of inch at the tire OD. The shape of the graph will be similar either way, but the magnitude of the result will vary greatly. Left and right side should be very symmetrical.

[Tamvette]

I don't know about later Gens, but the G2 manual warns against more than 3/8" total stack thickness under each rack mount. I would assume all are similar.

I think the TKO kit trades the shim stack with a constant thickness spacer, and moves the adjustment to the outer tie rod end height.

You should be measuring either degrees of toe per wheel, or decimal of inch at the tire OD. The shape of the graph will be similar either way, but the magnitude of the result will vary greatly. Left and right side should be very symmetrical.

Just to be clear, after alignment, we used this bump steer gauge to only do a sanity check, these results are after installing the tko kit with no changes to spacer.

I am not following you on the shim spacer, you could add shims on top of tko kit. If you look at the first post, it is about half of the factory shim thickness. Our goal was to measure every inch of suspension travel with bump steer gauge and leave it alone with tko spacer unless it toe in with suspension travel, which is what we ended up doing.

[TKO MOTORSPORTS TEAM]

The .375 thickness warning is for chassis frame rail to tie rod clearance. If you raise the rack to much you can run into chassis clearance problems at full bump full lock. .

Yes your correct Dean we moved adjustment more to steer arm side so we could correct the bump steer as much as possible.

Bump steer is measured in thousandths of an inch or MM in the motorsports world. Using a simple bump steer gauge with dial indicators works best. Bump steer gauges are dirt simple and they give you a real nice visual measurement acting directly on the suspension so you can see whats going on at the wheel. Measurement works like this . EX: .005" toe in per one 1 inch bump travel.

The goal is always to get "zero bump steer" through entire suspension travel. BUT when your working with factory production based vehicles zero bump steer is difficult due to mfg tolerances , static caster , design criteria and packaging.

Hope this helped Dean let me know if I missed something or you have questions...glad to help

[GTS Dean]

I'm really not sure about the purpose of the spanner shim in the first place. Perhaps to lessen the number of shims typically required and/or to reduce deflection of the rack mounting cross member?

[TKO MOTORSPORTS TEAM]

I'm really not sure about the purpose of the spanner shim in the first place. Perhaps to lessen the number of shims typically required and/or to reduce deflection of the rack mounting cross member?

We had a customer purchasing our bump-steer kit with questions about the the rack spacer today.

Few reasons for a billet aluminum steer rack spacer.
1. the Factory spacers are plastic and tend to wear out if you track your car alot . The plastic spacers wearing out is not a big issue for 90% of viper owners but still an issue so we decided to fix the issue since we were there
2. one piece billet spacer is much easier to install then a bunch of silly plastic washers
3. Billet one piece spacer is more precise, less crush side to side, less load on rack
4. Red hard anodize is simply for corrosion resistance, durability, and red is one of our company colors

Hope this helps if there are more questions glad to help answer them

[GTS Dean]

I thank you for the response. FYI, the Gen 1&2 cars had steel spacers with black oxide finish. Would you please read post #7 above and comment as appropriate?

[sharmut]

The steering rack in my ACR has developed more play over the years from repeated track use/abuse and being replaced. While doing so, will update to the TKO bump-steer kit, along with their control-arm bushings and camber lock-outs.
Will also look at the wheel bearing seals, the rears are prone to leaking more so than the front. If you track your viper a lot, watch those rear wheel bearings, can't imagine it would be good if all the grease dries up and bearing seizes.

[TKO MOTORSPORTS TEAM]

For sure 5th gen viper rear wheel bearings have a limited service life compared to other vehicles. When you do check the rear wheel bearing you will see grease that has pushed out past the seal and shield which is totally normal and actually a good thing. Just wipe the grease off best you can and inspect after evert track event or every couple thousand miles. Just for reference timken rear wheel bearings we have replaced at 5000k miles. Most of those miles were very hard track miles. The bearings were still in good shape it was just precautionary replacement.

[sharmut]

Thanks TKO, one of the rear was replaced late 2018. At the current track day rates, I plan to replace them every 2 years as a precaution. Are you guys looking into providing a more robust inner tie rod? I seem to wear the passenger side with regularity.

[TKO MOTORSPORTS TEAM]

Thanks TKO, one of the rear was replaced late 2018. At the current track day rates, I plan to replace them every 2 years as a precaution. Are you guys looking into providing a more robust inner tie rod? I seem to wear the passenger side with regularity.

Hello Sharmut
We dont have any plans on upgrading the inner steer rack joint on the factory steer rack right now. You can only go so far with factory steer racks due to the strength of the rack casting. The next step would be to build a billet aluminum rack with a better ratio, high quality rack and pinion gears, rod ends and better plumbing. Same type of rack we use on racecars; big problem with this is cost for our customers vs performance gains.
Sometimes with drivers if we experience problems with continued equipment failures that are out of the ordinary we look at driving style. Minor adjustments in driving style can save money , lower lap times and get you more on track time. Not saying driving style change is the magic answer it just might be something for you to look at.