6 Bolt Vs. 7 Bolt on 4G63 Block

[ZABMANN]

what are the defferences between the two?

 

[rEclipserGST]

6-bolt can take hits with a grenade launcher

7-bolt is liable to get crankwalk

Do a search, and dont you DARE ask "What is crankwalk?"

 

[xioca]

I think it's the number of bolts on the flywheel.

 

[live4my4g63]

yea 6 bolts on the flywheel or 7 depending what motor, 6 bolts are stronger. everyone i know has built a 6 bolt and they are so much stronger than a 7 bolt, youll be happier with a 6

 

[ozzie_1978]

You can tell the difference by the oil pan. Do a search and you'll come up with some pictures.

 

[TALONTRAX]

6 bolt = strong

7 bolt = less than strong

If you`re going to build a 4g63, build a 6 bolt. They`re just better. Period.

 

[kottyking]

The differences:
7 bolt- 7 bolts to the flywheel, 8.5:1 compression, thinner rods, slightly different ports on the head, ceceptable to crankwalk tho its not as common as people make it seem.
6 bolt- 6 bolts to the flywheel, 7:8:1 compression (usdm), big rods

 

[DSM1G90]

Why the two different motors is basically due to the turbo and the piping.

6bolts had larger turbos with larger TB opening and larger runners heading to the motor. Thus with this configuration is why of the lower compression to handle the larger volume of airflow coming in. Also with this is why of the beefer connecting rods

7bolts, due to the need of quicker spooling and more horsepower (190 vs 210) went with a smaller turbo (Garrett T-25), smaller TB opening and slightly narrower runners. The tradeoff from the volume factor to quicker airflow was the reason for this change. Also, 7bolts went with a slightly different ignition system - taking out the CAS at the end of the INT cam and putting the sensor down at the crank - prob was to get more accurate timing signals from a direct method that where the cam has variations due to belt tensions...

With this quicker airflow, the motor can spin quicker, yet, to get it to spin quicker was to put in thinner connecting rods to reduce motion weight, to allow the pistons to "push" down faster for increased torque, and also allowing higher compression ratios (7.8:1 to 8.5:1) with the required 91 plus octane fuel (why 1Gb and 2G turbos had "Use Premimum Unleaded Fuel Only" listed in their gauges - 1Ga's 6bolts still used the "Unleaded Fuel Only" listings..since they can use 87/89 REG unleaded fuel in stock 450cc form).

True, do some searches .. does a body good.