6 bolt vs. 7 bolt [merged] 6bolt 7bolt 6-bolt 7-bolt six bolt seven bolt

[asdfzxc]

All 6 bolt vs. 7 bolt threads are merged here.
How do I tell if I have a 6 bolt or a 7 bolt?
Will x part from a 6 bolt fit a 7 bolt?
Will x part from a 7 bolt fit a 6 bolt?
Which one is better?
How do I swap my x bolt for an x bolt?

What is the difference between 6-bolt and 7-bolt engines (aside from the obvious - 6 vs. 7 bolts connecting the flywheel )

Is there an advantage over either of the two engines?

Thanks,

-Mike

 

[talondude4]

It's a 6bolt.

 

[blcknspo0ln]

if you want to double check, on the backside of the valve cover (towards the firewall), on the left, there should be a circular unit bolted to the head. that is a cam angle sensor. if you have one, it is a 6 bolt. if it's a triangle, or none at all, it is a 7 bolt.

you can also check for an indented oil pan too

 

[Black94DSM]

^ Go with what he said, because you never know if the owner before you swapped the engine out for a 7 bolt.

But your car did come with a 6 bolt from the factory.

 

[talondude4]

if you want to double check, on the backside of the valve cover (towards the firewall), on the left, there should be a circular unit bolted to the head. that is a cam angle sensor. if you have one, it is a 6 bolt. if it's a triangle, or none at all, it is a 7 bolt.

you can also check for an indented oil pan too

Checking the oil pan is more acurate.

 

[moostafas90dsm]

thanks its a six bolt....

 

[boostjunkie02]

my 6 bolt turbo crank pully has a chip out of it and it eats belts. can i put a 7 bolt crank pully on and it work or are they different

 

[barfoot1]

The 6 and 7 bolt pulleys have different part numbers, but either will work. After market crank pulleys are not 6 or 7 bolt specific.
http://www.extremepsi.com/store/customer/product.php?productid=17448&cat=603&page=1

 

[Nessuno]

I am swapping my 2g head to a 1g head. I was just wondering if I should buy the head studs for a 6 bolt or a 7 bolt? Another one of my concerns is the water pump. I plan on replacing it. Same deal. 6 bolt or 7 bolt?

 

[dsmgrimreaper]

just run 7 bolt water pump, and 7 bolt head studs, easier no problems.

 

[startech]

I have a 7-bolt non turbo block that I am trying rebuild to make a 6-bolt turbo block. I have noticed no oil squirters, which i am not worried about. But my old turbo 6-bolt crank block has wider mains for crank bearings VS the 7-bolt non turbo. I would rather use the 6-bolt crank but would I need wider crank bearings similar to the middle thrust washer for all of the mains. New to rebuilding anu help will be grateful.

 

[91tsirasinhell]

I know you don't want to heat this, but you need to just go pick up you a rebuildable 6 bolt block. You should be able to pick u p a good for for around 100 bucks or less.

 

[TurkF26]

i also agree that there is no way you are gonna make a 420a motor built with 6 bolt 4g63 parts

 

[MCDGexx]

Can you buy NEW 6bolt motors? or is it not possible?

 

[FusionTalon]

well theres places that sell them completely redone, not sure if u can go straight thru mitsu to get a new one...

 

[MCDGexx]

So only Mitsu knows how to make new ones?

 

[luvmygst]

So only Mitsu knows how to make new ones?

They might not be the only one that know how but they are the only ones that do. Buying a new motor from mitsubishi is a pointless thing to do. For the money that you would pay a stealership you could biuld a nice motor. A reallly really nice motor. And as far has having non turbo 7 bolt. Is it a 4g63? I think they might have came in the 93-94 nt cars. If so then putting a 6 bolt crank in a 7 bolt block is also a pointless thing to do. Most people attribute crankwalk to the block any way no the crank. If you want a 6 bolt just buy a 6 bolt and rebuild it. As far as rebuilding the 7 bolt alot of people say that the c/w problem is overrated. Its just up to you if you want to take the chance or not. But keep in mind that the 6 bolt has c/w also, just not as often. Godd luck.

 

[TurkF26]

its very pointless to even try to rebuild a 7 bolt when you can fine 6 bolt turbo motors for cheap. Some in my area with 132xxx miles on them for 125 or so for the block.

 

[luvmygst]

I dont think so I just rebuilt mine. I just didnt want to go through the hassle of the swap rignt now. I am building a 6 bolt though, but I am using the 2g head with a smim. The 7 bolt is a good motor if you take care of it and have a little luck with the c/w demon.

 

[MCDGexx]

so is there a difference between an old one you fix up and a NEW one from factory?

 

[TurkF26]

ive seen plenty of rebuilt 7 bolt motors go to crap too.. its all personal prefrence but why go back to a 7 bolt when you can get a 6 bolt for cheap and its really not that hard to put one in a 2g.

 

[luvmygst]

so is there a difference between an old one you fix up and a NEW one from factory?

Yes you can build one that is better and stronger than the factory motor. Do you think that the drag cars you see go to the dealership and buy new motors? The aftermarket makes parts to hold up to high horsepower applications. The factory makes good motors, but you can build one or have one built that will outperform it in every way.

 

[TurkF26]

so your building 6 bolt motor and putting a 7 bolt head ontop??? why??

 

[luvmygst]

Because the 1g head flows more up top, but the 2g head with its smaller runners has a higher velocity producing more midrange power. If I were building a all out drag motor I might consider a 1g head but for my street car I want the power where I can use it. Done right with a good set of cams and a valve job I think it will perform just as good a a 1g, with a better powerband.

 

[my98gsx]

i have a currently have a 1998 GSX with a 7 bolt motor in it, that i just blew the head gasket in. While i am fixing the problem i am also installing WEB 272 cams and putting a fresh oil pan gasket on as well. My question is, i have a set of almost perfict 6 bolt pistions that i was thinking about putting in the engine while the whole car is wripped apart. the only problems i am thinking about it A- will these pistons be a DIRECT fit for my stock pistons ( and will they lower my comp. ratio ) B- will i lose power from this mod. and C- if there is a power loss will i still want to do this anyways because of the fact that i want to swap out my 14B for a 20G this upcomming summer anyways ( it might be safer to run 15lbs of press from the 20G throught a lower comp. motor. ) if anyone has an answer for me please let me know.

 

[the_red_pooch]

I'm not so sure this swap would be worth it, I would probably advise differently. This is somewhat the opposite direction most people normally go. Since the 1g rods are better and the 2g pistons are better you would be essentially taking the worst parts of the two motors and creating one. The CR would be lower though(7.8:1 instead of 8.5:1).