NAVY

Hi guys i want to know what the Differences between 400+ C.I Stroke and big bore engine ( 370 ,377 , 383 , 387 ) C.I for Forced Induction work ?

second question

some people clain that stock crank in risk for 700+ rwhp ( There is no balancing) in crank , If so will the ARP Main Studs bolts solve this Problems ???

I Believe there is no difference between stroker and big bore engine in hp .

I NEED ADVICE


thanks
navy

badcoup

Stroking and boring an engine are both ways of increasing displacement. A stroked engine generally makes torque at at lower engine rpm than a large bore motor od the same displacement. But there are many other factors that contribute such a comp ratio rod length stroke ratio etc. It's only as good as the heads supporting it as well. Main studs will help but not eliminate the issues with the crank. A good forged crank/rod setup as well as a good balancing job go along way for longevity.

NAVY

Something to the effect that unites dangerous in the project stock crank and big headunites Supercharger


thank you a bout good Information a to crank badcoup


thanks
naavy

CarsandWomen

iTrader: (19)

bottom ends bone stock down to the rod bolts have been pushed close to 900 whp, its all about supporting all the rest of the motor and not giving it un-needed stress.
shorter strokes will operate in slightly higher rpm ranges and generally utilize larger cams to support this, badcoup is also right on every point.
plus, "theres no replacement for displacement" is not entirely true, forced induction is the replacement. so its a little more about what you want to do with the motor.

so. what is your end goal? that should help narrow it down bunches

98Z28CobraKiller

iTrader: (17)

Stock crank is good to 1000 rwhp. It's been done a bunch of times. Now, with a blower belt pulling on the snout, it might be a different story. As for bore vs stroke, I prefer bore.

CarsandWomen

iTrader: (19)

x2

Gonoma

iTrader: (15)

x3 on the bore for FI

slow67

iTrader: (2)

This is why blowers are harder on cranks....

WAHUSKER

iTrader: (4)

In general: The longer your stroke the slower your engine will rpm & as stated already it makes it's torque lower too. The engines turning 10,000 rpms are usually de-stroked. Case in point the original 302 ci Z28s, de-stroked 327s if I remember correctly.Changing other componenets can change this, but all things being equal.....

As for a stoke cranks limits, yes it can be done but why would you want to risk the motor over it? I'd go forged on any motor making over 600hp. It might not break, but it WILL flex, which will at least cause more wear & tear. And if you are running a blower, that snout can break off or flex enough to ruin the front bearing.

Don Gartlits put a camera inside a motor many years ago & was amazed at what he saw. Crankshafts & camshafts flexing, rods stretching, too high oil pressure resulting in zero flow. Hi volume is what you need. Like boost, big psi numbers do not tell the story, it's all about volume.

My $.02

JBarron

^^That is very interesting. I never thought about it, but I can definitely picture it. I mean, the illusion is that metal is rigid, isn't it.

CarsandWomen

iTrader: (19)

top fuel crankshafts will flex as much as 20 degrees worth of rotation, a hairline fracture in the same crank can result is as much as 50 degrees. meaning when the motor is perfect 2 cylinders maybe as much as 20 degrees advanced or retarded from where they should be. yes there is flex, A LOT of flex. but the thing is, its normal, expected, and planned for.