How to figure Displacement

[AJ'S 88NA]

Does anybody know how to figure displacement? I know stock 7m is 2954cc. I've got +6.5mm overstock on the stroke which I think stock is 91mm plus, .060 over pistons. The place that I got the stroker kit from said +665cc with stroked crank and .060 bore. 3619cc? Any online formula just does't compute to that. Maybe I'm screwing up on the conversion from in. to cc. :icon_conf

 

[GotTurbos?]

pi * radius^2 * height (x6 because its an i6)

I got 3169.78cc with your specs.

 

[AJ'S 88NA]

pi * radius^2 * height (x6 because its an i6)

I got 3169.78cc with your specs.

Thanks. The formula I've seen says bore x bore x .7854(constant) xstroke x 6.So 3.327 x3.327 x .7854 x3.833 x 6 = 3276.32.
Anybody else have a different way to figure it?

 

[IJ.]

And for those of us too lazy to bother with the math these days there's this...

 

[Nick M]

Area of a circle, remember that? Area times the stroke times cylinders. The stroker kit only makes about 3.2 litres. You do need a large overbore to hit 3.6.

 

[IJ.]

Number of Cylinders are = 6 to 1
Piston Diameter = 3.267 Inches
Piston Oversize = 0.060 Inches
Engine Stroke = 3.838 Inches
Computation Results:
Computed Engine Displacement (CID) is 200
Computed Engine Displacement (Litres) is 3.3
Computed Engine Displacement (CC) is 3280.6

Brave man that bores a 7M out to +.060"
(Hope it's a late model thick block with minimal core shift)

 

[Nick M]

I am pretty sure our two stroker engines here that I know of left it at 3.2 litres.

 

[AJ'S 88NA]

I agree with Grumpy. I found the old thread with the caulcuator and if you plug in the fig. it comes out to 3240.7. If you use the formula in the thread (.0031416/4) x 84.5 x 84.5 x 97.5 x 6 = 3280.65. That's close to what the stroker supplier says(3282cc). Just wanted to check with you guys (eyeball on the supplier) . Thanks

 

[IJ.]

AJ: If you was going for a +60 bore make sure you get the block sonic checked first (as well as using a late block as there just isn't enough meat in an early one)

 

[AJ'S 88NA]

It's a 88na bought it new wayyyyy back Grump. I've got another block just in case. Just trying to get enough air and fuel to make it run better now( Maft Pro and other mods.) Got a couple of thou. miles on the rebuild no sign of any prob overheating or anything.

 

[starscream5000]

IIRC the blocks changed around either in mid '89 or mid '90...

 

[IJ.]

Cool the NA's went thickwall earlier than the GTE's and should be a nice block with minimal core shift.... my new 92 block was way off centre.....

 

[AJ'S 88NA]

Good to know my machinist was very anal about the spec. when he put it all together. With the apexi I had on and stock injectors and stock afm dynoed at 215hp and 207 torque. Just had a dip in the power climb at about 3800rpm figured it could use some more fuel and air.