2.4 question

[beeztsi]

well this is the 2.0 forum but i figured i should post a question on a 2.4

my friend is starting/ thinking about the 2.4 build up since his car is to damn slow (12.1 on hrc 20g) .......... he just recently bought a t66 and was thinking of ways to take full advantage of that size of a turbo.


my question is ive heard the redline on a 2.4 stroker not 2.4 hybrid?? ive been hearing 6500 and is there a way you can increase the ability for the engine to take higher rpms

 

[Wilsonman02]

A T66? on a freakin 2.4. With a redline of 6500. Jeez good luck spooling before redline. But to increase the rev or redline of an engine. You'll need new cams,springs,valves,spring retainers. And jeez man he better port everything and get a 25 shot to get that turbo to spool.

 

[beeztsi]

yeah hes getting a 100 shot dp of nx and hes one crazy guy, he knows his stuff with dsms hes got a website i dont know if its up yet www.dsmstuff.com i told him the same thing

that 12.1 was on a full weight 2g with a 1.66 60'

 

[lambertvr4]

Typically the rev limit will be determined by valve train capability. Our valvetrain is very capable from the factory. I've twisted 8K on a stock head on my GVR4 numerous times. Not that I recommend it. If the valvetrain can do its part, then you have to consider the capabilities of the rotating assembly (crank, rods, wristpins, pistons, etc.). You get into pistons speed, piston acceleration near TDC, piston jerk, side loading on the piston/rods, etc. You don't want to shock the combustion charge too hard or it may lead to detonation quickly, nor do you want to have extreme side loading on the rods. You can figure all this out mathematically w/ rod ratios, strengths of materials, etc. or you could just assume that Mitsu knew what they were doing from the factory. If the stock 4G63 redlines at 7K and you can twist 8K no problem, then I'd stick with that on a stock motor or somewhere between the two. The longer stroke on the 4G64 gets into that side loading, etc. I mentioned above so the redline is lower; say 7K to be safe. The stroker motor uses the '64 crank, stock rods, and different pistons (one configuration anyway) and it's safe to say 7K is the top redline. Maybe 6.5K even. The '64 is the same beast. The deck height is higher, so no need for different pistons. Redline should be the same as the stroker.

The T66 and the stroker/'64 will be a lethal combo. Hope he has the rest of the car to match that much air. Not to mention the tuning capability and tools to make it what he wants. Should be insane when it's done. Surely not just a low 12sec car anymore.

 

[beeztsi]

thanks

 

[DSMu4ia]

A 2.4l is NOT a stroker motor. A 2.3l is.

2.4 is a regular block combo offered.

2.4's can get spun to 9k.

2.0's a tad over 10k.

People spin stock 4g63's to 8500. No internal work.

T-66 is too big. Regardless of who you are.

 

[rdrkt]

Originally posted by DSMu4ia
A 2.4l is NOT a stroker motor. A 2.3l is.

2.4 is a regular block combo offered.

2.4's can get spun to 9k.

2.0's a tad over 10k.

People spin stock 4g63's to 8500. No internal work.

Very good. Everything you said here is correct. Its great when people actually spread fact as opposed to misinformation.

Originally posted by DSMu4ia
T-66 is too big. Regardless of who you are.

Actually this is a little incorrect. All of the pros in the street class running big times like Hill and Shep are running turbos right around the T-66 size. They use a turbo around that size in conjunction with a 125 or more DP wet shot to get themselves down the track. This works out pretty well for a race car. But this would be a huge money pit with crappy boost response in anything resembling a street car.

In my case I am going with a 4g64 bottom end with a big t3/t4 60-1 I think that should spool under 4k while making 550+ hp on c16 no nitrous. To me that is a pretty nice combo for a strip/street car.

 

[Polk]

2.4's can get spun to 9k.

I would not want to do this on a day to day basis. The rod ratio (1.49) is a little too harsh for that kind of rpm. On a race motor who cares, but not on a street motor.

The 4G64 only has about .150 think cylinder walls. The 4G63 has around .250. With this much side load and that kind of rpm you can split the cylinders pretty easy.

If you are going to be doing this you had either better fill the block(race use only), sleeve the thing, or do both.

The 64 motor is beast on the street with easy spool-up. You really don't need to turn the thing that hard to get you going. Big bore and a long stroke make for a happy turbo.

Now for a t-66 being too big of a turbo. Well maybe for a street car, but for a race car, to me that is a little small.

Polk

 

[DSMu4ia]

My T-66 opinions..

Since this is posted on DSMtuners, I would base any of my comments on the people who post here.

A T-66 is way too much turbo for damn near anyone on here IMO. Also, I was basing it on a street car, along with supporting mods. With all the new hybrid turbo's out, something in the T-4 lineup, isn't a good choice IMO for most street cars. Now on a race car, it's something else entirely different. When you are just trying to make "only" ( I know) 500whp on just gasoline, there are much better options in the hybrid/bolt on category. Why would you want something that doesn't spool til 6k?


As for spinning any motor on the street to 9k, I wouldn't do it everyday of the week either. Case in point, you are hard pressed to find many roads that allow to redline many gears. Hell, when my 2g fwd was running, I would short shift it at 6k most of the time on the street, as it was at a less chance to miss a shift, and it just felt like I was being easier on the car.

As far as street driving, ala everday, most people would chose pump gas for economical reasons. There's very few cars I've seen that can spin past 8k or so on pump gas, without a decent amount of knock. Sure there are people who can tune it out, but personally on the street I don't see a reason to rev much past 8k anyways.

Hope this makes sense, I have to go start drinking in a little bit and I didn't want to type too much.