[glamcem]

Originally Posted by SPORTBIKES

How are you doing with the 325? Have you had the on the track? They do look similar to these 305s with this cut I have. My guess is that the wheel has different measurements then the MRRR, but when they cut them, they used the same offset. These were the first time to be fitted to the Camaro.

I've been using my car primarily at track (very low street miles) and quite happy with the 305/325s. Rear end gives a lot more confidence on corner exit. I just need stiffer suspension to accommodate the additional grip as it feels like there's too much grip for the current suspension (limiting factor for the new available grip) and as a result it's only marginally better than the OEM setup because of that.

[SPORTBIKES]

Originally Posted by glamcem

I've been using my car primarily at track (very low street miles) and quite happy with the 305/325s. Rear end gives a lot more confidence on corner exit. I just need stiffer suspension to accommodate the additional grip as it feels like there's too much grip for the current suspension (limiting factor for the new available grip) and as a result it's only marginally better than the OEM setup because of that.

So.. you are running the track with that amount of poke and you have not experienced and rub?

[glamcem]

Originally Posted by SPORTBIKES

So.. you are running the track with that amount of poke and you have not experienced and rub?

yes with the current camber and rear offsets, I haven't experienced any rub. When I had 305/30/19 Trofeo Rs I had a slight rubbing at one spot but it didn't happen again after adding a bit more camber in the rear. Overall tire diameter has to do a lot with that

[SPORTBIKES]

Thanks for the input!

[BowtieRocket]

Originally Posted by glamcem

I've been using my car primarily at track (very low street miles) and quite happy with the 305/325s. Rear end gives a lot more confidence on corner exit. I just need stiffer suspension to accommodate the additional grip as it feels like there's too much grip for the current suspension (limiting factor for the new available grip) and as a result it's only marginally better than the OEM setup because of that.

BMR? I'm currently replacing rear end suspension components then swing arms and end links

[glamcem]

Originally Posted by BowtieRocket

BMR? I'm currently replacing rear end suspension components then swing arms and end links

I was referring to the whole suspension. Nothing against BMR but I would personally wait for the OEM ZL1 1LE parts for the sways, control arms, end links..etc since historically OEM GM parts were not that expensive especially for being spherical bearing components, weight is also another factor

[RUQWIKR]

Originally Posted by glamcem

I was referring to the whole suspension. Nothing against BMR but I would personally wait for the OEM ZL1 1LE parts for the sways, control arms, end links..etc since historically OEM GM parts were not that expensive especially for being spherical bearing components, weight is also another factor

The sway bars from the ZL1 1LE are lower rates due that car's high spring rates vs the SS 1LE. Just FYI.

[glamcem]

Originally Posted by RUQWIKR

The sway bars from the ZL1 1LE are lower rates due that car's high spring rates vs the SS 1LE. Just FYI.

Makes sense, thanks for the info.

[Ryephile]

Originally Posted by RUQWIKR

The sway bars from the ZL1 1LE are lower rates due that car's high spring rates vs the SS 1LE. Just FYI.

Oh? That is fascinating. Do you have a source? First I've heard of that.

[RUQWIKR]

Originally Posted by Ryephile

Oh? That is fascinating. Do you have a source? First I've heard of that.

I asked an owner to measure diameters and whether solid or hollow. I'll try to dig up his measurements.

[RUQWIKR]

Originally Posted by RUQWIKR

I asked an owner to measure diameters and whether solid or hollow. I'll try to dig up his measurements.

The FE4 suspension (ZL1, SS 1LE) use ~30mm hollow front and a solid rear (~27mm) based on when we had them off a while back. The FEA suspension (ZL1 1LE) uses almost the same size front and rear bars, though, the rear has three adjustment points as we've seen. When he put a caliper on it, it measured a bit over 26mm each with the front seeming to be a fraction bigger than the rear.

I think the FEA's are both hollow based on the weight in the dealer ordering system where you can look up package weight when you go to order a given part number. I don't remember the weights, but, the FE4 rear was many pounds heavier than the FEA rear. The FE4 front was a bit heavier than the FEA front.

Hope this helps.

[MoreSpeed]

Originally Posted by jaymsu

I run Apex PS-7 ET25 19 inch square with 285/35/19 RE71R.

I like to be able to rotate them around.
These are directional tires so I can't do side to side rotation but I just flipped tires on the wheels (making left become right, right become left) so I can get more life out of it.

You can actually run them in the wrong direction with little impact on grip... that is as long as it dry. Don't ask me how I know.

ps. in the wet, you are funneling water to the center which is exactly what you don't want to do.

[Ryephile]

Originally Posted by RUQWIKR

The FE4 suspension (ZL1, SS 1LE) use ~30mm hollow front and a solid rear (~27mm) based on when we had them off a while back. The FEA suspension (ZL1 1LE) uses almost the same size front and rear bars, though, the rear has three adjustment points as we've seen. When he put a caliper on it, it measured a bit over 26mm each with the front seeming to be a fraction bigger than the rear.

I think the FEA's are both hollow based on the weight in the dealer ordering system where you can look up package weight when you go to order a given part number. I don't remember the weights, but, the FE4 rear was many pounds heavier than the FEA rear. The FE4 front was a bit heavier than the FEA front.

Hope this helps.

Well that's certainly a help, thanks.

One thing that always grills me about anti-roll bars is the material or alloy can be changed to give wildly different rates for the same dimensions. e.g. cheap thick spring steel vs. something like Swift's thin/light spring steel both can be the same rate. Also, the hollowness does make a rate change, but not proportional to the weight loss. This will end up in the category of "we'll never really know" unless someone actually measures their spring rates.

[RUQWIKR]

Originally Posted by Ryephile

Well that's certainly a help, thanks.

One thing that always grills me about anti-roll bars is the material or alloy can be changed to give wildly different rates for the same dimensions. e.g. cheap thick spring steel vs. something like Swift's thin/light spring steel both can be the same rate. Also, the hollowness does make a rate change, but not proportional to the weight loss. This will end up in the category of "we'll never really know" unless someone actually measures their spring rates.

Understand...as you were discussing, wall thickness, material, etc. can make a huge difference. Based on the price points, I don't think anything exotic is going on with them.