Performance 2T-ZE design

[Radar]

Ok so I'm trying to build a decently powerful 2T-ZE (2T + Supercharger + EFI), but I'm mapping it out on paper first to make sure it's the optimum of what it can be.
I'm trying to figure out all the main design principles I need to look at to make sure I get what I want.

So far I've covered a few of what are what I'm assuming, are relatively important design principles.
Bore/Stroke - Rod/Stroke - Cranking Pressue - DCR - SCR - Intake length - Exhaust length - Boost - Cam Timing (Overlap, lift, duration) - VE% - Rotating Mass.

What other design principles can I look into to make sure it turns out the way I want?

*Different motor not an option*
*Reading material*
Cranking Pressure - http://www.chevyhiperformance.com/te...ion/index.html
Dynamic CR - http://www.empirenet.com/pkelley2/DynamicCR.html
Rod/Stroke ratio - http://www.hondatuningmagazine.com/t...tio/index.html
Bore/Stroke ratio - http://en.wikipedia.org/wiki/Stroke_ratio

[Kedderz]

Just use a 4agze.

[WhiteSx]

BMEP - Brake mean effective pressure

[Duk]

Exhaust length -

From what I' ve read, on boost exhaust tuning is a non event. Just make sure that there is no excess back pressure. Off boost (low throttle) exhaust tuning theories should still apply tho.

What other design principles can I look into to make sure it turns out the way I want?

Use a decent supercharger like a new Eaton/Magnuson, Toyota superchargers are as old as the hills. Good intercooling and make sure that there are no boost leaks.

[Radar]

Supercharger is a .87L Twin screw Kenne Bell and Yes intercooled

[river]

Hi,

Just use a 4agze.

Agreed. The 2T is a fine engine, and if this is only an exercise to see what power you can drag out of a 2T, then fine. However, your time and money would be better spent on a later generation engine such as the 4AG, 3SGE, etc, which lend themselves more easily for greater power.

seeyuzz
river

[Radar]

I agree, sure the 4ag, or 3sgte would make plenty of power straight off the bat, just isn't what I'm after...
I wanna drag out as much power as possible while keeping it reliable..

[Radar]

**Good read**
Dynamic Compression vs. Static Compression

The compression ratio listed for any engine combo is always the static compression ratio, which is fixed via component selection and machining practice when the engine is built. As you've surmised, it assumes the cylinder is full of air and fuel at bottom dead center (BDC) and that all the mixture is compressed into the top dead center (TDC) combustion cavity. But an engine really doesn't begin making serious compression until the intake valve closes and seals the air/fuel mix in the cylinder. That's why engines with identical static compression ratios can have significantly different cranking pressures, as seen with a common compression gauge. Although part of this is due to displacement differences (a larger-cubic-inch engine is a bigger pump), the main influence is camshaft design. By changing certain cam parameters, it's possible to bleed off cylinder pressure on the bottom end, decreasing fuel octane sensitivity, even though its static compression ratio remains unchanged. The actual cylinder pressure an engine sees is often referred to as dynamic compression, because (unlike the static built-in compression ratio) it changes dynamically according to camshaft variations. The most important of these variations is the intake closing point, because it extends beyond BDC into the compression stroke. Closing the intake later aids top-end power at the expense of low-end torque. Down low, where the engine is most likely to detonate, the late intake closure bleeds off cylinder pressure, effectively dropping the dynamic compression ratio.

Rod length and crankshaft stroke also play into the dynamic compression equation because they alter the piston's position within the cylinder at the intake-valve closure point. How all this comes together is explained by KB Pistons' John Erb: "Consider a 10:1 Chevy with a 3.48-inch stroke, 6-inch center-to-center rods, and a very hot race cam that closes the intake at 90 degrees after bottom dead center (ABDC). This engine will think it is running with 6.17:1 compression and will be happy with 80-octane fuel. As a general rule, the best available pump gas will work with an 8.0:1 dynamic compression ratio. To get 8.0:1 with the preceding rod, stroke, and cam intake closing event, you would need about a 13.2:1 static ratio."

Erb's 8.0:1 dynamic guideline is for classic, old-school, all-iron engines. An advanced, high-tech engine can go a point or so higher-but even with the latest high-tech electronically managed engines, actually shooting for a 10:1 dynamic ratio is way too high. Calculating the relationship between piston position in the bore and intake closing point and then determining the effective dynamic compression ratio requires some pretty serious math, but KB Pistons has a Web-based calculator that makes it simple-just plug in the requested numbers.

*Hot rod mag - http://www.hotrod.com/pitstop/hrdp_0...on/index.html*

[roadkill]

Hi,

to be honest mate this sounds like an awesome idea! The only thing i want to know/ask is if you are going to use the single cam or twin cam head? Twin cam would be best for cam timing issues and ease of making into an efi engine. I always wanted to supercharge me 18rg but just never got around to it....

Watching and waiting.

bEn

[Radar]

Nah mate, single cam, for what I think is good reason too.
(I've already purchased a special grind schinder cam anyways)
The only difference in head design between the 2TG (67) and 2T(63) is about 4degrees intake angle and the fact one is twin cam.
Solid gear set will last longer and be more reliable than chain in a high HP application.
Pushrods have that beautiful mechanical sound.
EFI is no worries, in the middle of purchasing 3T-EU manifold.
1 cam IS cheaper than 2.
2T's are a dime a dozen - 2TG's cost an arm and a leg when u crack the head.

End of the day as long as you,
A)Buy your cam to suit your motor
or
B)Build your motor around your cam
It shouldn't honestly matter one cam or two unless they are variable timed.

[roadkill]

Hi,

sounds good. I was just thinking some of the efi gear would be cheaper on a 2tg and more common, the 3teu sorts that out though. I like the idea of reliability though with going single cam. Much less to break but yet easy to get replacements!

bEn

[Radar]

Just double checking here, but with my static compression that I need for my cam.
I'm fairly sure 10:1 SCR will give me an 8.3:1 DCR, that's using the degreed part of my cam. I.E. 254 degrees ABDC 57 @.050 clearance
If I were to do the same calculations with the actual cam specs
I.E. 288 degrees ABDC 74
I'd need at least 11.5:1 SCR to reach 8.3:1 DCR.

So do I work from the point of flow... .050 or from the actual stated cam specs?

[jeffro ra28]

Good on ya for being different

But the use of a the 2tg will make it a hell of alot easier to tweak cam timing and be far more practical to "play with". The cost compared to single cam is very marginal. Infact, twin cam may even be cheaper if you start playing with expensive parts associated with a high a revving pushrod engine (roller lifters, bronze lifter bores, roller rockers, heavier valve springs).

I also disagree with much less break on a single cam pushrod engine. There is a shit load more to break infact, and much more likely to. But that all depends on what your budget is i suppose. By the sounds of things, budget doesnt seem to be a problem tho.

Just my 2c.

[roadkill]

Hi,

been thinking a little bit about this and remembering the absolute bullshit times and power they get out of turbo 3tc's in the states and i think it shouldn't be too hard at all. Parts can be a little diffiicult to get cos of our location but can be had easily from the states. Fairly sure there are a few interchangeable bits between the 2t and 3t. Could always slap on a 3t head and wind up the boost too!

Keen on seeing the 2tze

bEn

[Radar]

The 3T pistons use a 35mm pin height and the 2T pistons use a 39mm pin height.
So If I want to use the 3T pistons with the 2T crank I need 5.007" rods...
Not too worried about the cam tuning.
I'm fairly sure due to the wide LSA, minimal overlap, hi-flow exhaust and correct compression, it should run about 3000-8000
I just like the mechanical pushrod sound mixed with roller rockers..