six bolt swap important mod?

[pur97tsifwd]

Is a six bolt swap that important b/c its not on the upgrade path and alot of people tell me you should do it for more relibablity.

 

[JDNSBR]

No, a 6 bolt swap is not necessary. If you want to eliminate the crank walk worry then yes, do it. However, I am a firm believer that crank walk is caused by poor oil pressure because the mains are the last thing to see oil in this set up. So if you have a good strong seven bolt and your oil pressure is good then, no. IMO keep a good eye on the oil pressure and you should be fine.

 

[importboost]

It is a personal preference, yes the 6 bolt has had better luck with the crankwalk issue than the 7 bolt. But theoretically any motor can crankwalk. Its just not a common thing. If you have the cash and you want a good project, do it. Its a great learning experience and you get a better flowing head, better turbo, and overall setup IMO. But like i said its personal preference, just watch out for signs on your 7bolt for crankwalk.

 

[bryanwheat]

Is a six bolt swap that important b/c its not on the upgrade path and alot of people tell me you should do it for more relibablity.

If you are going to be keeping the car stock, or close to stock (using the t-25) I would reccomend just keeping the 7 bolt. If you are going for higher hp, than i would highly reccomend going with the 6 bolt motor. Certain parts of the 6 bolt motor are actually performance upgrades, the 1g heads flow alot better than the 2g heads, yet the 2g heads are designed for better velocity, and produce more low and mid range torque. The 1g intake manifold has larger runners, as with the tb is 60mm, verses the 54mm of the 2g. As for the motor internals, the 1g 6 bolt motor uses rods that are capable of handling 450 hp everyday, and some people have proven them to take over 550hp. The main problem with the 7 bolt motor is not the crankwalk/bottem end bearing problems, but that the oil squirters are placed in the same oil cavity that the oil to the bottom end (main and rod bearings) are in. On the 6 bolt motor the squirters are in the main oil gallery. So there is plenty of oil for the bottem end. Not that this is in any way the contributor to crankwalk and rod bearing failure, there has been mass studies, that involved cutting miltiple 6 and 7 bolt blocks in half, and cutting them into slices to view the oil passages. In the study they took the oil squirters out of the block, and cam to the conclusion that the oil squirters were opening up at 5-10 psi. Than it is basically acting as a pressure regulator, and only letting the main and rod bearings recieve 5-10 psi of oil, at idle, all the way up to redline, 10 psi is certainly not enough oil pressure for a high performance motor truning 7k rpm. If i had to reccomend you a good motor, i would go with a 6 bolt block, crank, rods, arp studs, 2g pistons, and possibly go with the 2g head and intake with a 1g throttle body.

 

[dsmgrimreaper]

i dont believe in driving stock cars mod mod mod its funner and yes 7 bolts are good motors its mostly driver error and poor oil pressure that kill them.

 

[iboostdoyou]

If you are going to be keeping the car stock, or close to stock (using the t-25) I would reccomend just keeping the 7 bolt. If you are going for higher hp, than i would highly reccomend going with the 6 bolt motor. Certain parts of the 6 bolt motor are actually performance upgrades, the 1g heads flow alot better than the 2g heads, yet the 2g heads are designed for better velocity, and produce more low and mid range torque. The 1g intake manifold has larger runners, as with the tb is 60mm, verses the 54mm of the 2g. As for the motor internals, the 1g 6 bolt motor uses rods that are capable of handling 450 hp everyday, and some people have proven them to take over 550hp. The main problem with the 7 bolt motor is not the crankwalk/bottem end bearing problems, but that the oil squirters are placed in the same oil cavity that the oil to the bottom end (main and rod bearings) are in. On the 6 bolt motor the squirters are in the main oil gallery. So there is plenty of oil for the bottem end. Not that this is in any way the contributor to crankwalk and rod bearing failure, there has been mass studies, that involved cutting miltiple 6 and 7 bolt blocks in half, and cutting them into slices to view the oil passages. In the study they took the oil squirters out of the block, and cam to the conclusion that the oil squirters were opening up at 5-10 psi. Than it is basically acting as a pressure regulator, and only letting the main and rod bearings recieve 5-10 psi of oil, at idle, all the way up to redline, 10 psi is certainly not enough oil pressure for a high performance motor truning 7k rpm. If i had to reccomend you a good motor, i would go with a 6 bolt block, crank, rods, arp studs, 2g pistons, and possibly go with the 2g head and intake with a 1g throttle body.

very good post, I agree with that almost completely. The head isnt that big of a difference. With a turbocharged application, the flow of the head really wont make that much difference unless you are running very high horsepower. A 6bolt block with 2g head isnt a bad idea necessarily, it just really isnt necessary unless you plan on really making some power. Unless your dead set on getting a 6bolt, just stick with the 7bolt, its been proven over and over to be a reliable engine capable of holding oodles of power and boost

 

[veloz]

AH yes, the 6-bolt debate.

I'm currently running a 7 bolt.
Mostly stock.

Im my garage I have a 6 bolt. just needs a nice rebuild.

I'm going to go with the 6 bolt for a few reasons.
1) external oil cooler
2) stock rods capable of handling 550 HP. SInce I am only looking to have about 400 as a daily driver, it is a cost effective method of doing so. I'm gonna stick to a ported 2g head though, just cause that 's what I have and I don't want to mess too much with the harness
3) less chance of crankwalk. I've seen a crankwalkd 2g motor and it was not pretty . HUGE hole in the case.
4) I got a good deal on it.

I know guys that have made good power on a 7 bolt with no problems.

Either way you go, keep an eye on your boost and our oil pressure. Disconnect the clutch switch and always let your car heat up and cool down. you'll be okay