criticalx

383 build
- slayed lt1 block
-1.9 dome diamond piston with Thermal Coating
-12.3 compression
-eagle forged crank
-eagle 6in h beem rods
- total seal rings
-dart pro 1 heads ported flow 286@600 291@700
- heads cnc soften for nitrous
-cam motion specd cam 248/260 640/623 112 solid roller tight lash
-1.6 comp pro magmum rocker
- victor e efi with nitrous spary bar
-lpp long tubes
-off road y with bullet muffler
-42 lbs injectors
-bbk 58
- 200 shot nitrous
-3600 stall
-3.73
-mt pros 275 60 15

what u think think bout setup? besides intake
Mid 10s on motor and low 9s on nitrous do able?

criticalx

Anyone

criticalx

Thanks for input.

bufmatmuslepants

iTrader: (3)

Why do you need domed pistons to get to 12.3:1? You want a quench of 0.030-0.040, so if its zero decked, use an 0.036-0.038 head gasket, if 0.010 in the hole use 0.026 gasket.

criticalx

I bought the parts from a guy doing a build. So this what I have
To work with.

bufmatmuslepants

iTrader: (3)

What does it mean "heads CNC soften for nitrous"

Shownomercy

iTrader: (1)

I would guess he means chamber softening, you sacrifice a few CC for a polished surface. Cuts down on hot spots and makes flame front slower.

Fancy stuffs for LT1 land.

bowtienut

iTrader: (1)

Of course its do-able. Not necessarily because of that parts list. Heck, you could take the simple little motor out of my car and run mid 10's NA and high 9's on a 100 shot in a lighter F-body. I wouldn't try the 200 on it though
It's much more about the machining and assembly work, tuning, and the REST of the car setup than it is about the parts list.

criticalx

I got it to 1.413 60' 10.565@126 on hci stock short block and 150 shot safe tune. Heads was just local port guy flowed like 260@580. Hoping with better handful parts. I can get more out it.

hrcslam

Are you zero decked? 12.3:1 seems low for a dome piston on a 383.

criticalx

I have not put it together yet.. block was decked for the new surface for the cometics gaskets. Not sure it was zero decked. Gonna check once piston in hole. Also heads are like 60 cc

criticalx

Got efi single plane intake with 200 shot spary bar and elbow.. gonna add 58 tb.

Puck

iTrader: (17)

You will have the power, but we know nothing about your weight or suspension which is just as important for a good ET.

criticalx

3290 with me in it.

Drag bar
Tq arm
Lca
Relocation brackets
Panhard bar
50/50 drag shocks
No front sway bar
Front other stuff stock

criticalx

got motor running. i had so many issue so far.. but made one half *** pass 11.6

criticalx

nitrous setup don't want that much quench. u open up quench and add dome piston to get compression back up.. my motor was built off monte smiths tips..

hrcslam

First I've heard of not wanting a tight quench. Care to elaborate?

Edit: So I researched this. Makes sense, so with a softened head and increased quench distance you should have a bigger window for tuning the nitrous. How does the dome play a role in the process? My understanding is the purpose of softening the head and increasing the quench distance is to slow the burn down, but so will the dome piston. Is there a point where it hurts performance and longevity? Seems like you can go with more nitrous?

criticalx

Improving Quench To Optimize Nitrous Use

One item that’s been on the radar for the past few years is loosening the quench in each cylinder to improve the performance of the mixture’s burn. That goes along with chamber softening, which involves machining out the center of the combustion chamber to a predetermined dimension.

If the engine is not set up properly, it can be very timing-sensitive, and the timing can be dialed back only so far before it becomes a point of no return where power does not improve.

“Loosening the quench dimension opens up the chambers and helps to prevent the engine from detonating, which gives the tuner some leeway in terms of the timing lead they can put into the engine,” says Johnson. “Lowering the static compression and using the correct camshaft can be the difference sometimes in three or four degrees of timing that could be added to the engine if it’s built properly.”
There’s no standard in terms of chamber softening angles; each cylinder head is different, in terms of chamber shape, valve angle, and chamber depth, all of which affect the ability to soften them up. For example, an LS cylinder head or small-block Ford head will typically have a very small chamber and flat valve angle, where the valve is very close to the deck of the head, so it’s more difficult to soften the chamber as there isn’t much meat to work with.




Your only goal is to light the fire, burn it clean, and get it out of the cylinder. – Monte Smith, NOS/Monte Smith Performance
Conversely, an 18-degree big-block Chevrolet Big Chief-style cylinder head has plenty of material to permit rolling the edges of the chamber back and opening it up without fear of running into the valve face or valve seat.

There’s no standard dimension in terms of quench, but .060-inch is a minimum number to shoot for to improve performance. Some big-blocks will have much more than that.

“The heads you have to work with dictates what you’ll be able to get away with,” says Johnson.

The engine’s static compression ratio also comes into play when adding big loads of nitrous oxide. As there’s more than one way to skin a cat, compression ratio can be adjusted through gasket thickness, piston dimensions, chamber dimensions, whether the piston is down in the bore, and more.

Many builders are loosening up the quench dimension and then adding a dome to the piston to raise the compression ratio. The whole point is to slow the rate of combustion and burn the full load of fuel and nitrous, especially in a small-block engine with a small combustion chamber.

criticalx

http://www.enginelabs.com/engine-tec...nitrous-oxide/

bufmatmuslepants

iTrader: (3)

So 0.036-0.038 is too tight for nitrous? Where do you draw the line on how big of a shot warrants opening it up? Like 100-150 ok for less than 0.040, how far do you want it for 200 or more? Or is 150 and less than 0.040 still too tight? Are they talking about 3-500 shots with the 0.060? What was Taner using, I know his motor did over 700hp on 11.5:1 compression, explains why he had "lower" compression, but I don't think he had domes. Where's Ed, or Moe, who can give us a little insight on nitrous tuning? I saw gregrob is back, hasn't come in here to play though, he might have some info.