AC427s delrin bushing kit, my 2 month impression!

Sniperdog

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I don't believe their are controls arms by themselves. Kenny Brown sells a kit to replace the bushinged stock subframe for a hardmount unit and comes with new control arms with "improved geometry". But honestly, the claimed weight savings and geometric changes aren't worth the expense or the changeover especially when you read through Bruce's experiences with the unit. This IRS is awesome, and this bushing kit is what reveals its true potential. Everyone claims the Cobra IRS is SO heavy and says it sucks...The new Camaro's IRS weighs 390-lbs. Noooo spank you.

Great review and pics OP!

10-4,., thanks for the info and sorry about the highjack.,., :-D
 

keith89

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I just got my full kit with tie rods yesterday! They are amazingly well packaged and organized. I can't wait to have them installed.:banana:
 

03 DSG Snake

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Rock on modified IRS Brothers and go spank some Corvettes for me! :burnout:

:thumbsup::coolman::beer:

Any problems with getting the new bushings in if the Subframe and/or Control Arms are painted/powdercoated? :shrug:
 

ac427cobra

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Any problems with getting the new bushings in if the Subframe and/or Control Arms are painted/powdercoated? :shrug:

If the bushing bores in the control arms are powdercoated those areas would need to be sanded or honed to remove the paint. The subframe would not matter.

This kit is a VERY precision fit and parts are machined to incredibly tight tolerances, unlike other kits on the market.

FWIW

:thumbsup::coolman::beer:
 

03 DSG Snake

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If the bushing bores in the control arms are powdercoated those areas would need to be sanded or honed to remove the paint. The subframe would not matter.

This kit is a VERY precision fit and parts are machined to incredibly tight tolerances, unlike other kits on the market.

FWIW

:thumbsup::coolman::beer:

Been over the instructions numerous times. Any chance of rust after cleaning the holes with wire wheels? I'm assuming the bushing grease keeps any corrosion in check.
 

skaarew04SVT

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Any problems with getting the new bushings in if the Subframe and/or Control Arms are painted/powdercoated? :shrug:

I made sure the bores were clean prior to bushing installs. any painting / priming i did on the UCAs/ LCAs and any powdercoat on the subframe i removed with a wire wheel brush and/or wetsanded the bores.
 

ac427cobra

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Been over the instructions numerous times. Any chance of rust after cleaning the holes with wire wheels? I'm assuming the bushing grease keeps any corrosion in check.

The instructions say to use a 2" diameter wire wheel to clean the bores for the subframe bushings. Once the bushings are in, there are no worries. In 25 years when the car is getting restored they can simply reclean the bores and install new bushings if they wanted to. But I really doubt the subframe bushings can wear out?!! :shrug:

The only other place you have steel bores would be the UCA's. They are tucked up and out of the way enough that corrosion would not be an issue. Plus there will be plenty of grease around the area to prevent any rust.

:thumbsup::coolman::beer:
 

Jroc

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hmmm...

That rear suspension setup looks familiar for some reason. :dw: :shrug: :idea:
 

Jroc

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Kenny Brown maybe?
Jeff

lol.

No. He is running the same combo that I have been for over two years.

375 lb front/575 lb rear MM C/O's with MM valved Bilstein Sport shocks/struts, Bruces IRS kit, and a Billetflow IRS brace.
 

Ontariomystic

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Have you checked your pinion angle? My 04 Cobra needed all the spacers on the bottom to get the pinion angle close. Rear end does look sweet. I should have detailed mine.
 

svt2ner

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I bought the package about 2 months ago with the beefed up tie rods, have yet to install. usually takes me a good 6months + to get the motivation (time) to do installs when I buy stuff.

But I will say the packaging is superb :)
 

skaarew04SVT

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Have you checked your pinion angle? My 04 Cobra needed all the spacers on the bottom to get the pinion angle close. Rear end does look sweet. I should have detailed mine.

yes i got it close. if you notice in the pics of the diff that the bolts / nuts are not tightened down yet. the washers i posted are just there until i got the rear end in the car to perform the final alignments. HOWEVER, i only shifted one washer each to the bottom side.....pretty much looks like the pics!
 

PWORLDSTANG

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yes i got it close. if you notice in the pics of the diff that the bolts / nuts are not tightened down yet. the washers i posted are just there until i got the rear end in the car to perform the final alignments. HOWEVER, i only shifted one washer each to the bottom side.....pretty much looks like the pics!

I missed those diff bushings in there. The black anodizing fooled me, I thought those were stock. :lol1:

So even with the aluminum differential mount bushing, you didn't notice any change in NVH?
 

skaarew04SVT

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I missed those diff bushings in there. The black anodizing fooled me, I thought those were stock. :lol1:

So even with the aluminum differential mount bushing, you didn't notice any change in NVH?

with the aluminum bushings....the 1st time i drove it i heard a tiny bit of gear noise with no radio on. now i dont even hear it....especially over the quiet borla / steeda mufflers i have. all you will notice is no wheelhop and a huge freakin smile from the improvement in overall vehicle feel!

i imagine u would hear a bit more gear noise with 410s....but on the stock 355s its next to negilgible
 

PWORLDSTANG

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with the aluminum bushings....the 1st time i drove it i heard a tiny bit of gear noise with no radio on. now i dont even hear it....especially over the quiet borla / steeda mufflers i have. all you will notice is no wheelhop and a huge freakin smile from the improvement in overall vehicle feel!

i imagine u would hear a bit more gear noise with 410s....but on the stock 355s its next to negilgible

That is interesting, I've always been under the impression that aluminum diff mounts were noisey with or without gears. Gear whine, even the slightest bit, would drive me crazy! However, you're not the only one to say that there is no change in NVH with this kit. That's a huge plus for this kit IMO.

Bruce, what is it that keeps your aluminum diff mount bushings quiet, compared to MM's aluminum diff mounts that definitely make noise?
 

ac427cobra

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That is interesting, I've always been under the impression that aluminum diff mounts were noisey with or without gears. Gear whine, even the slightest bit, would drive me crazy! However, you're not the only one to say that there is no change in NVH with this kit. That's a huge plus for this kit IMO.

Bruce, what is it that keeps your aluminum diff mount bushings quiet, compared to MM's aluminum diff mounts that definitely make noise?

This NVH issue is a VERY subjective opinion. A lot depends on the individual person and the individual car and how loud the exhaust might be. I did a bushing kit install on a car last year that had fairly loud exhaust and stock gears and I could not hear the front diff mounts, and I know what they sound like! A car with stock exhaust and stock gears will make some noise, guaranteed. 4:10's will even be louder.

Here are two Q&A's from my FAQ:


Q: "How much increase in NVH will I see with this kit?"

A: The change in NVH will hardly be noticeable with the exception of the aluminum front differential mounts. They are a tad on the noisy side. Worse if you have 4:10 gears. If you have an aftermarket exhaust that's loud, it will help mask the noise from the diff mounts. Some have used the sound deadening matting available at car stereo shops to minimize the sound. It's a self adhesive matting you put down on the floor pan right above the differential. It's called Dynamat and it's also available at Eastwood.

Q: "How bad will the noise level be with 4:10's?"

A: 4:10's are definitely going to raise the noise level particularly with the Aluminum front diff mounts. As mentioned above, if you have loud aftermarket exhaust, that will help. Some people put down Dynamat on the floorpan directly above the differential and that seems to help a lot. Some say it's noisy, and others have said it's not bad. It's like asking what the best beer is. You won't get the same answer from any two people.


Full FAQ can be found here:

faq's

On the other hand, after driving the car with the "new found thrill" in the IRS you will have more tolerance for a little extra noise because you will be so thrilled with the transformation the IRS has now morphed into.

A few customers have said it's pretty loud. Many customers have said they hear no difference. Some have said they hear it but it's no big deal. They decide they'd rather have the noise along with awesome improved handling as opposed to the hop and crappy handling before the kit.

:thumbsup::coolman::beer:
 

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