TeamSwift

Anyone know what considerations should be made when swaping in gt rods and new pistons (vitara's) with a stock 3 cylinder crank. I'm not familiar with odd 3cyl balancing. Does heavy metal need to be added to the counterweights due to the heavier rods and pistons? Does a t3 turbo crank already have this balance?

I have a t3 turbo engine comming from Canada and could use it's crank. Also are there any other diferences to the crank. A car and driver article about MK1 turbo sprints told of "rounded" counterweights and other prep.

I apreciate anyone who can answer this for me.

I checked manuals for a 94 metro and an 86 sprint. Both use the 3 cyl. crank. The only info I can glean is that the piston pin is offset 0.5mm towards the major thrust side in the stock 3 cyl. motor to accomodate change in thrust pressure as it travels. I'd bet all 3 cyl rods are the same. The cranks are counterweighted and balanced already - no extra metal is needed that I know of.

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'94 Geo Metro xFi 240,000
'86 Chevy Sprint ER (frame up repair in progress)

Suzuki built these engines great, everything is balanced independently. That's why you see very little gain when actually blueprinting and balancing these motors. They aren't crappy domestics where you have to keep everything as a set.

Just buy a reaally good .01 gram resolution scale, with up to 500 grams of weighing ability, and static balance the piston/rod assemblies. I have the three in my G10 within 2 grams total of difference across all three. It idles smooth as a babies ass with polyfilled engine mounts, cut off crank pulley(lacking A/C pulley), GT flywheel, and GT rods/pistons. With a Suprfly lumpy cam, which is supposed to be set around 1000rpm, but idles great for me at 900rpm.

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My cars:

J. McBean: '98 Suzuki Swift 1.3L 16v SOHC 5sp+ "Mk5" Made in Canada
The Mini Rattler: '94 Suzuki Swift .993L 6v SOHC 5sp+ "Mk3" Made in Canada *The Winter Beater*
B. Berry: '90 Chevrolet Turbo Sprint 1.0L 6v SOHC 5sp+ "Mk2" Made in Japan

I got 18MPG in a 3cyl with a 5 speed manual 4dr, '93 Metro!

I've static balanced my assemblies, and it adds 15-30 minutes to the assembly time, depending on your grinder.

2 grams is a lot of weight to throw around, and 500 grams may not be sufficient capacity.
You can buy a nice triple beam balance with better precision and a higher capacity (2610 g) currently for $70 (one available at that price) at Amazon.com. Their new balance is only $89 and ships from Arbor Scientific. I especially like their special styrofoam packing, so the scale ships safely. When not in use, it can be stored safely in the original packing.
This is a 'nice' to have, not 'need' to have tool, but one which will last a lifetime, requires no batteries, and is very accurate.
Using a 'Lark MB2610'

('Ohaus' knock off) I got my assemblies within .01 grams (significance of 0.1g) of each other.
(about the weight of a dime sized piece of toilet paper...or less)
If you buy one of the cheaper used triple beam balances from Ebay, make sure you get the 3 weights that go with it.
Also, be aware that it can be damaged in shipping if not properly packed; this is a precision instrument.
Currently, they have 25 balances for less than $70.

Are you sure you balanced your assemblies within 2 grams of each other, or did you have more precision?
(What type of scale/technique did you use?)

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DIY Broken Bolt Removal: viewtopic.php?f=22&t=41042
DIY Clutch Adjustment: viewtopic.php?f=9&t=48281
DIY Wheel Bearings: viewtopic.php?f=2&t=29003
DIY Shocks: viewtopic.php?f=10&t=45483
DIY Wheel Align: viewtopic.php?f=2&t=42479
Once you get the cars dialed-in (compression, leaks, bearings, alignment, brakes) swap in new rubber and glass, you've got something which should last for years!

Shipping is murdersome for us that don't live south of the border. :p

True, the full assembly clocked at around 756 grams IIRC... which I probably don't.

I was stuck with a digital scale that went to the hundreths of grams and had a max weight of 500 grams. That 2 grams is max that I am out across all three, when weighed on a 5kg max scale. I matched components. If I remember correctly, when I added it all up using the much more accurate scale it was 1-1.2grams of difference between heaviest and the lightest.

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My cars:

J. McBean: '98 Suzuki Swift 1.3L 16v SOHC 5sp+ "Mk5" Made in Canada
The Mini Rattler: '94 Suzuki Swift .993L 6v SOHC 5sp+ "Mk3" Made in Canada *The Winter Beater*
B. Berry: '90 Chevrolet Turbo Sprint 1.0L 6v SOHC 5sp+ "Mk2" Made in Japan

I got 18MPG in a 3cyl with a 5 speed manual 4dr, '93 Metro!