partsca18 to ca20

[badintentions]

ok well i have a ca18det and am thinking of useing some of the internal parts from the ca20 in the stanza but will it work is it just bored ot or is it a longer stroke somting can this be done by swaping cranks etc or am i barking up the wrong tree

[IggyEGuana]

The deck height of the ca20 is taller. Extra 0.2l is from the stroke.

CA stroking is a bad idea IMO. But if u really wanna u need..CA20 crank with custom length (shorter) rods and CA18DET pistons.2 probs here. 1 is the longer stroke brings the piston to a lower BDC position. Either modification to pistons/block/oil squirters(mod or delete) wil be required or it wont be possibly at all due to the bore being too short.2nd prob is even if you can get it all together you will be left with an unfavorable rod ratio (rod length vs stroke length). Too sharpe of an angle makes for bad motor mojos.

if you go for it have fun and post it up for the rest of us

gl

[bimeur]

for a CA20 swap,you need:

/CA20 crank

/4G63 rods,and modified at the head(different diameter)

/a special timing belt

/custom forged piston(because of the pin,it's lower in the piston,compared to the CA18 one)

/CA18 girdle and crank studs(longer,because of the girdle)

/you have to drill holes for the oil squirter

i think that's all

but you can mix internals,like CA18 crank and rods,with CA20 pistons and block,etc.....

[mbmbmb23]

for a CA20 swap,you need:

/CA20 crank

/4G63 rods,and modified at the head(different diameter)

/a special timing belt

/custom forged piston(because of the pin,it's lower in the piston,compared to the CA18 one)

/CA18 girdle and crank studs(longer,because of the girdle)

/you have to drill holes for the oil squirter

i think that's all

but you can mix internals,like CA18 crank and rods,with CA20 pistons and block,etc.....

In another thread on here (regarding the CA20DET) the counterweights of the CA20 crank hit everything in the CA18 block as it was spun...so I think you need to add a CA20 block to your list.

for a CA20 swap,you need:

/CA20 crank

/4G63 rods,and modified at the head(different diameter)

/a special timing belt

/custom forged piston(because of the pin,it's lower in the piston,compared to the CA18 one)

/CA18 girdle and crank studs(longer,because of the girdle)

/you have to drill holes for the oil squirter

i think that's all

but you can mix internals,like CA18 crank and rods,with CA20 pistons and block,etc.....

I dont think the ca20 crank will spin in the CA18 block. (as seen here zer...8rb26)

[float_6969]

That's not a CA20 Crankshaft. It's from something else.

The CA20 crankshaft spins in the CA18 block just fine.

If I were going to do it, I'd keep the stock CA18 rods and get custom pistons with a smaller wrist pin and have it moved up 2.2mm on the piston. This may require a shorter skirt and other changes to the overall design of the piston.

[bimeur]

In another thread on here (regarding the CA20DET) the counterweights of the CA20 crank hit everything in the CA18 block as it was spun...so I think you need to add a CA20 block to your list.

I dont think the ca20 crank will spin in the CA18 block. (as seen here zer...8rb26)

yeah,sorry,i forgot to notice that,you MUST use a CA20 block with CA18 internals

[float_6969]

NO, you're not understanding. That post is NOT of a CA20. It's something completely different.

the CA20 crank WILL fit in the CA18 block just fine, BUT it moves the piston up 2.2mm and you have to correct this. You have to either get shorter rods (prob not a good idea, I'll explain in a bit) or get a custom piston with the wrist pin moved up 2.2 mm (better idea, and this is was Tomei does in their stroker kit as does Norris Designs in the UK).

The latter is a better idea. This is because if you increase the stroke from 83.6mm to 88mm and then shorten the rod from 133mm to 130.8mm you get a rod ratio of 1.02(130.8/88). This is a VERY small rod ratio and would cause a considerable drop in potential revs and a substantial amount of side loading of the piston in the bore, which increases wear, internal friction, and costs you power.

If the stock rods are kept, that moves the rod ratio up to 1.51 (133/88). This is a much more reasonable ratio. Stock on a CA18DE(T) is 1.59 (133/83.6). Stock on a CA20 is 1.70 (149.3/88). This is a relatively high rod ratio for a 2L 4 cylinder. By comparison the rod ratio of an SR20 is 1.58 (136.3/86) and drops to 1.48 (136.3/92) with an SR22 stroker kit. The KA has a rod ratio of 1.72 (165/96). You'll notice that both the KA and CA20 were both designed for similar purposes and both tend to handle boost in the same way, which is poorly.

If you're wanting to modify the CA20 block to accept the DOHC head, you NEED to plan on forged rods and pistons. The stock CA20 rods are INFAMOUS for not handling much power. Also be aware that the increased deck height MAY cause clearance problems with the hood and front strut tower bars.