I was wondering if any of you out there could tell me the differences between the 6 and 7 bolt 2.4L 4G64s? Are the differences the same as the 4G63 6 and 7 bolts? Would it even be worth it to build up a 7 bolt 4G64? Thanks!

No, ask V8killer on here.

The difference is not the same. Most people build the 2.4's as a race motor to be beaten on. Most people drive around with a 2.0 7 bolt. A stock 2.0 would probly last longer. Chris' didn't last 2 weeks if I remember correctly. QPR will not even build another 7 bolt.

7 bolt 4G64s can be a successful engine configuration, look at ecoli's '99 GSX. 664whp on a set of Eagles & Wisecos with the 7 bolt 4G64 isn't exactly too shabby. :bounce:

With like 3 1/4 mile passes and I have no clue how many street miles (probably not many) For all we know it's walking too...

twin plate clutch vs. act 2900
dyno time and a few pases vs. few thousand miles and a few track passes
I wish shane the best of luck, but imo the 7 bolt 4g64 is a bad decision. The machine work required to make it 'safe' is very expensive.

Whatever guys, Shane's motor is gonna hold together fine. :rant:

Im sure his motor has seen plenty of dyno miles

With the twin plate is the crank seeing less clamping force than the stock set up?

lots of clamp, less pressure on the crank though

I didn't waste my money on ARP mains or CRCO dowel kits that probably only make the problem worse. I spent $130 in machine shop labor. The motor will probably blow up before it gets a chance to crankwalk. I am not the only one out there making high HP on a 7-bolt 2.4, I am not even the only one in the 10s.

I have a built 7 bolt 2.4 as well. All new stock parts were used except eagle rods and ross pistons. I'm pushing 7000 miles and at least 8 trips down the quarter mile. I would NOT recommend building a 7 bolt. I started building mine over 2 years ago when people were still hoping the 2.4 was less prone to crankwalk. It's since been proved that it's probably just as bad as the 2.0 as far as your chances of crankwalk go. I wanted to do the 7 bolt because it's less work to install in a 2G, but the paranoia of having a 7-bolt at this point was/is not worth it. Why risk it?

If you do build a 7-bolt consider doing what this guy did:
http://www.dsmtuners.com/forums/showthread.php?t=8817

Creating dowel pins sounds like a really good idea.

When you're done I'd go with a twin-plate clutch to be safe. I'm running the HKS and the pedal pressure is like stock but it's really chattery.

That's been done, it's the CRCO kit mentioned above. That didn't seem to fix the problem. Personally I'll take the 6-bolt anyday. The one I built last year still runs great with no endplay whatsoever, now if the rest of the car performed as well as the engine does. :headache:

The CRCO kit is not the same as what that guy is talking about. Hey's talking about creating alignment dowels for the whole girdle not just the bolts (kind of like the dowels on the caps for the cams).

Ok, so I'll stay away from anything 7 bolt and just build the 6 bolt 4g63 thats sitting on my garage floor.

On the same lines is it recommended that anyone going 2.4L go with a Twin Disc Clutch?

or what's best for the Crank Walk senario?

Scenario fyi

Well - in general.

550-650whp range.

depends on what kind of power, what type of driving, and how long you plan to make it last.

I wouldn't recommend people building any 7-bolts. But I am a cheap ass who didn't want to buy a bunch of new parts for a 6-bolt. I also think that any 7-bolt that crankwalks very soon after being built didn't crankwalk from the traditional 7-bolt reasons. It took most 7-bolts 2.0ls 60,000-100,000miles to crankwalk. When a newly built 6-bolt crankwalks, and it does happen, nobody trys to instantly blame it on it just being a 6-bolt. But if a newly built 7-bolt crankwalks, everybody just assumes it's because its a 7-bolt.

In Carey's motor, the dowel pins are the traditional CRCO bushings. The thrust surfaces were aligned very carefully. As far as assembly, this year we have done 16 fully built engines, almost half 2.4's, all 6 bolts except Chris's. One walked, you do the math. 7bolt + heavy clutch = bad idea. Personally, before this year, I have built well over a hundred various motors from bikes to stroked v8's with not one bearing spun, or assembly issue in any of them. Can anyone else here say that? We are looking into the use of hardened pins as well, the machine shop we use is the best around and if it can be done correctly, they can do it. It could help, but I wouldn't bother without using higher load bearings and a pressure plate that causes less pressure on the thrust surfaces.

Personally, I don't think Shanes motor is in any more danger of walking just due to the twin plate clutch. How many of the fast 7 bolt motors out there are on 2900 6pucks as opposed to twin disk? One of the engines we pulled out of a 2G that was walked and showed up on a trailer was built by a reputable shop with Crowers, JE's and ARPs as well as a 2900 pucked clutch . Go figure I am not sure it made it more than a couple thousand miles either with a lot less demands on it. Question is, how many times does a person have to be hit before they figure out they should duck?

speaking of that other 7 bolt Crank walked kid - I saw his car in Apple Valley a couple times in the last week or so.

What did he end up doing for a motor? is he still using his 2900, and rods/pistons?

how long has he been driving it?

We built a 6 bolt for him, he had it in denver for a bit, I think he was just home from school when you saw him. At any rate, probably been a month or two now. We still have his old crowers and JE's from the seven bolt, we took them as trade for part of the bill if anyone is set on building one of these things, let me know ;)

A 7 Bolt buildup just doesnt make sense to me. Its a fact that the 7 bolts are more prone to crankwalk, esp. when you are using a high pressure clutch setup. Its kinda like Raptor said, if you leave your stove on when you go to the store, dont be suprised when you get home and your house is burnt to the ground.