Just talking about taller gears and loading the turbo is like talking about a blind date with a girl that has a great personality... It's only part of the picture.

You need to get to the whole picture. For example, I run 4.10s with my 408 and I load the turbos beautifully. Why?
1) I'm not running a huge *** race thumper turbo. I spec'd my turbos for close-to-off idle boost and I shift at 6k
2) I run an 80E
3) the exhaust pulse from the 408 is... well, damn amazing.
4) I run a nice converter for street/strip (3k)

Would I get better performance with 3.73s? I don't think so (obviously or I would have put 3.73's in the 14 bolt )

Spec your turbo right, and those 4.56s might be perfect. Spec your turbo via the internet (bigger is better) and you should look from some really tall gears


Having said all that, Tyler you also need to look at your torque curve. You've got a bigger cam than me, on less cubes, plus a carb style intake (that is the most beautiful one ever made!!). If you torque is relatively weak down low, think about taller gears, and then do the SyTy shuffle on the line to build boost (or run some squeeze out of the hole).

 

Erik the question is actually for me and I run less cubes than Tyler(5.3) and maybe that beautiful vic jr. We got some goals with the current setup but then we're gonna try these gears with a turbo and see what happens!

 

Ah sorry bout that Danny -- I saw Tyler's post and got all confused

You aren't losing anything either way -- you can always change gears!

What size turbo?

 

I'm not sure on the turbo yet. Haven't put a lot of thought into it yet but I do know it's gonna be rear mount and we are gonna try these gears out with my current converter as well as the bigger one. Just have to see how things work out!

 

SO...... Lets just say u have a huge.. thumper turbo... rated to twice what your engine will ever put out .... and you have zero problems with spooling it... makes boost all over even footbrakes 2psi ... will it become a turd?... I have run every gearset GM makes in my truck with a 4l80.. In your truck Eric if you went to a 3.73 from your 4.11 your truck would be a lazy turd?.. with gear you dont need so much power to move truck anyway ??....

 

so when you gonna start on this project danny?

 

Thants me. I run a 3.23 gear Circle D TB stall at like 2600. .96 a/r housing. My 60's suck. 2.0 is my best. 13.1 @104 with 10psi on a 26" et street. I cant build any boost off the line. I i have been told thats due to my .96. but i would like to swap to 3.73.

 

First, at the level where you need to start worrying about whether to run a 3.73 vs a 4.11, you aren't talking about one being a turd and one being a race horse. So let's take the discussion to 3.08 vs. 4.11 (or bigger). Is my truck going to be a lazy turd at 3.08 out of boost? Yes. Will it go like mad in boost? Probably not with my current snails. Can I change that to Yes/Yes? Sure -- bigger snails. However, do I need to do that? Nope I'm not focused on some monstrous peak number at this point -- I want constant gobs of power and chose my gear and my snails with that in mind (I also cared less about an ET than I did DD characteristics when planning the build).

Second,
I have a hard time believing in the tooth fairy too but to be fair, "problems spooling" is such a personal thing... And very much dependent on what you want. I really think you and I (if you are the Casey I think you are) should go for rides in each other's truck before we talk about boost ranges, etc. If for nothing else than it would be fun as hell

Third,
from the perspective of my goals as described, this is not performing at the line by definition (is it a turd? that's your characterization, not something I said ). I can footbrake more boost than the brakes can hold, even with the SyTy shuffle, and definitely more than the tires can use... Which means I've got plenty of gear, and foot braking into boost becomes slightly less important, because I can make it off idle, and load the turbos pretty much instantly.

 

Just curious as to what your times are with the twins? Sounds like you have a hell of a set-up.

 

It all depends on the setup I guess. As for Me I have had better luck with the higher gears. I run 3.73 gears and 29" tires and 60' in the low 1.4's off the foot break. Thats at 4900lbs, 4x4, 80e, 370ci, tc76 .96ar. No nitriois, no trans breaker, no 2step, no hydro boost.

Next plan is to try 3.42's because Im hitting the traps @6500rpm with the 3.73's. Well see if it kills the launch.