DrBlockHed

So I'm in the early stages of a H/C/I build, where I'm getting the work done said the Ls7 clutch would work fine for me and save me some money. I'm going AI 241 Heads, custom cam, fast intake, looking at low 400's to the wheels.

He also is a vendor for McLeod, is it a mistake to go ls7? I'm not afraid to spend money but am not in favor of pissing it away. I'm leaning towards the McLeod incase i want to go bigger later on (possibly FI) plus I've read a lot less bad about it.

Thanks

HCI2000SS

iTrader: (2)

I run a McLeod RST and love it. It feels like stock and holds my power easily

showdog75

iTrader: (8)

I'm in the midst of a ls swap and I bought a ls7 clutch after reading many good things about them. Since reading the good things lately I've read some conflicting things and now question my ls7 clutch purchase. I sold a good ls6 clutch because I was then told it wouldn't hold now I wish I had it back. The ls7 clutch is heavy and from my reading you lose throttle response due to the weight. I'm considering a aluminum flywheel to offset this.

2QWK4RU 06 GOAT

iTrader: (1)

Ls7 clutch is durable on a lighter car such as an f-body. It should last a long time unless you only drag race and do 5k clutch dumps all day long.

caturnbull1

iTrader: (2)

my car put down 438hp 405 tq. i have the stage 3 monster clutch. it is very stiff but i love it. it does not slip at all! car is not a daily either though. in traffic the clutch sucks from being stiff

DrBlockHed

What are your thoughts on the ls7 slowing the car down b/c they are so heavy? Is the RST that much better of a clutch? I have never been to the track, as of now I have a stock rear, so I won't be going near the track unless I upgrade.

98cherrySS

iTrader: (2)

The RST has a very small engagement window in my experience. I had an LS7 and swapped it for an RST. I liked the LS7 better but I do see why folks like the RST. It grabs and the pedal is very light feeling.

DrBlockHed

Thanks for the info, it seems like every post prior to 2009, everyone loved the ls7, now w/ the McLeod, Monster etc, it has fallen by the wayside. The guy at the shop told me he had it on his GTO which is a lot heavier than my TA and it held fine until he went over 600 rwhp.

I'm not obsessed w/ getting every single last HP out of the car, I'm looking for durability mostly as well as a good feeling pedal, I don't want it to be heavy as ****.

Darth_V8r

iTrader: (4)

Where you'll feel it is throttle response. The aluminum flywheel would help some.

Another item is the master. Lots of us upgraded the master to get more performance but it narrows the window. If you stay with a stock diameter master cylinder the window is by default larger.

DrBlockHed

I'm running pretty much stock now, just a full exhaust, lid and mail order tune. With the ls7 clutch I would feel a little delay in the throttle response? That doesn't sound fun.

Second, are you referring the engagement window? I had planned on doing a tick master since they seem to be almost a must with any addition of power. Would that make the clutch more of an on/off as opposed to the stock feel?

murphinator

iTrader: (2)

ls7 is heavy so it numbs the engine a bit in comparison to a lighter clutch and its harder on synchros trying to mate up all that extra weight , it is known for blocking out on shifts at high rpms some say do to being self adjusting but a recent post on here attributed it more to the extra demand on the sychros meshing up the greater mass.

I have one it drives like a stock clutch normally , has been durable , will tolerated being slipped , holds well which are all positives but the blocking out of gears is a big negative , It was in the car when I got it but at some point I hope to toss it in the can and get a clutch that I can shift quickly at rpm.

DrBlockHed

Thanks, that really helps, sounds like I'm better off going withy he mcleod and spend a few hundred extra bucks. Blocking out shifts kind of sucks, putting more stress on my trans is not acceptable, I don't want to save money now only to have to do a possible trans rebuild

2QWK4RU 06 GOAT

iTrader: (1)

The throttle response is definitely more delayed. More weight is good on a heavy car or just drag racing. The lighter stuff makes the engine come alive and feel like you picked up 20 rwhp. ..haha. rpm goes up quick and comes down fast with lighter assembly.

Darth_V8r

iTrader: (4)

The 7/8 bore tick master will have a narrow engagement window. The 3/4" bore will feel more like stock. Make sure you get the 3/4@ if you want a gentle window.

Darth_V8r

iTrader: (4)

For the synchros - remember their job is to speed match input shaft with gear. The higher Moment Of Inertia (MOI) your friction disc is, the more the synchros have to work. You can reduce MOI two ways. Lighter clutch or smaller diameter.

The aluminum flywheel won't help the synchros. It's the friction disc weight/MOI that makes this. Twin discs are generally lighter and smaller diameter. Both help reduce wear and tear on the synchros. The aluminum flywheel will make for crisper throttle response.

Trade off? Yes.

Lighter clutches make idle tuning more trickier. Your window will be more narrower. And price.

DrBlockHed

Thanks Darth, so will the heavier ls7 clutch screw up my trans? Does this become an issue only with hard shifting, higher rpms?

Darth_V8r

iTrader: (4)

it won't hurt your transmission for daily driving or GM couldn't warranty it. It will come into play at high rpm and hard shifting. In traffic you won't notice much, except a sort of sluggishness in lower rpms. The aluminum FW will help with that though.

DrBlockHed

Really appreciate it your advice, that sounds like it works for me. I don't really shift hard or at high rpms

Thanks again!

Rise of the Phoenix

iTrader: (27)

Checkout Monster clutches. I run their stage 3 clutch (good to 700rwhp/700rwtq) and I'm making around 450 to the tire. It's a great clutch and holds strong. It's also every easy to drive on the street.

DrBlockHed

Now I'm caught between the monster and mcleod twin discs.... The research continues!