6bot vs 7bolt

[Jon_0_3]

hey ppl wondering what the BIG differences between the 6bolt and 7bolts are. also what are the pros and cons of both motors there are a bunch of ppl telling me the 7bolts are better and i just want some more info to go into battle with. thanks

 

[Pure92TSi]

I don't know who is telling you that but they are wrong. The 7 bolts have a factory defect and have a tendency to "crankwalk." The 6 bolt motors are much stronger. This is why a lot of 2g guys do the 6 bolt swap. Your car is a 92 so it's possible that you have a 6 bolt motor. Check the build date in the door jam of your driver's door. If your car was built before 5/92 (i think) then it is a 6 bolt. If built after it's a 7 bolt. If you do have a 6 bolt, like I do, then your golden because you also have a stronger 4 bolt rear end.

 

[Raynehr]

6 bolt is the way to go. 7 bolts crankwalk bad, to cure the problem its more expensive than going and buying a 6 bolt block. stick with the 6 bolt and you will be fine ..

 

[Jon_0_3]

i have a 6bolt i was just wondering what the pros and cons where to both motors and y ppl would say the 7bolt is a better motor then the 6bolt

 

[FRIZZLE]

I got a 7bolt and i would much rather have a 6bolt just for the fact that they are much stronger.

 

[alex]

Ok, the reason you want to go 6 bolt is because they have more of an advantageto the 7 bolts. My 1990 Talon TSI AWD of course has the 6 bolt..........compression on it has 130 with brand new headgasket. My 95 Talon TSI AWD has a compression of 180 with brand new headgasket. The 6 bolts have a lot lower compression. That is why you can put unleaded fuel in the 1g 6 bolts. Being that you only have 130 compression with a new head gasket, you can turbo up the boost making the engine push out more air.......meaning an increase in compression. You can get strong 7 bolts, but when you want to raise the boost on them, your risking a lot, the compression on the 7 bolts it quite high the way it is compared to the 6 bolts. The 6 bolts are definelty to anybody's advantage.

I see your in Wisconsin, pm me if your interested. I have a couple 6 bolts laying around.

 

[Raynehr]

Stock for stock the seven bolt is probally a bit quicker, however just as described, also much more problem oriented. Try to stay away from them if you are going to be building something. After one grenades on you, and when they crankwalk most of the time they go bang!, you will never have anything to do with a 7 bolt again.

 

[1meanGSX]

Yes six bolts are a proven motor but 7 bolts also dont need as much boost to make the same horsepower as a 6bolt. 6bolt is only a 7.8 compression ratio which is very low and why when not on boost they are somewhat slow. 7bolts are a 8.5 compression ratio and it just about perfect for a boosted engine but still have decent power when not in boost. 6bolts heads and throttle body flow more air and because of the lower compression can handle more abuse and not have a tendency to detonate. But for the guys that speak of crankwalk like its a plague knock it off, look how many people that have successful fast cars with more than a 100 thousand miles on 7 bolts. You either have crankwalk or you dont and it only happens to certain cars and its easy to tell the symptoms. Overall you own a 92 with a 6bolt just stay with that, you can always rebuild it and bump it up to 8.5 compression ratio and basically have the best of both worlds. Hope this helps. Derek

 

[95blackGsTurbo]

I got a 7bolt and i would much rather have a 6bolt just for the fact that they are much stronger.

Completely false.6 bolts are so overrated. People need to get over the gotta have a 6 bolt so my car doesn't crankwalk. I would never pull out a running 7 bolt to put in a 6 bolt because it is "stronger" The only thing stronger about a 6 bolt would be the big rods. I like the 7 bolt because of the girdle for the main caps and the windage tray to keep oil from foaming up. Also they have little more compression which is nice. I have built up both and there was no difference. I even put 2g pistons in my 6 bolt for more compression. And the odds of a built 7 bolt walking are basically zero. Some people like the 6 bolt because of the 1g head which has bigger ports. Well the 2g is actually better because of the better casting. Ask Eric from AMS or the guys from SBR or AGP. Anyone who knows DSM heads knows that the 2g head is better flowing with mild work. It doesn't have near the casting flaws so it has smoother ports which allow air to move faster.

 

[1meanGSX]

Thank you BlackGST, 6bolts are good motors but 7bolts also are very good. Mitsubishi 7bolts have many improvements over 6bolts and crankwalk was a bad point but it is rare. Each engine has its stong point and people need to quick acting like 7bolts are inferior.

 

[Spoolin4Ever]

6 bolt has stronger rods AND crank.

7 bolt is also in 93 AND 94 model year cars; with 7.8 compression! Higher compression came with the 2G cars.

7 bolts crankwalk, and there is NO CURE/permanent fix. The 2G versions have a higher incident of crankwalk then the 1G 7 bolt cars (92.5-94).

You are supposed to run Premium in all the turbo cars, if not you get knock and the ECU retards timing, effecting performance.

Lower compression just allows you to run higher boost levels safely (assuming you have the proper ful mods and know WTF you are doing). The higher comprssion pistons like in the 2G cars help the turbo spool up faster.

Mosty people consider having a 6bolt engine with 2G pistons the best of both worlds. It's the most popular build option here by far.

It's cool to keep your 7 bolt as long as it's working; but it is considered unwise or at least very risky to put the money and time into rebuilding one, because it could still crankwalk or throw a rod or bearing after you build it.

So, if and when the 7bolt goes "bye bye", then the best choice at the time is a 6bolt engine.

And there are some people here that have rebuilt the 7 bolt, and it worked fine, there are others that have done it more then once, and even replaced with another 7bolt, and it crankwalked again!

 

[titogs95]

6 bolt has stronger rods

7 bolt is also in 93 AND 94 model year cars; with 7.8 compression! Higher compression came with the 2G cars.

The 2G versions have a higher incident of crankwalk then the 1G 7 bolt cars (92.5-94).

You are supposed to run Premium in all the turbo cars, if not you get knock and the ECU retards timing, effecting performance.

Lower compression just allows you to run higher boost levels safely (assuming you have the proper ful mods and know WTF you are doing). The higher comprssion pistons like in the 2G cars help the turbo spool up faster.

So, if and when the 7bolt goes "bye bye", then the best choice at the time is a 6bolt engine.

And there are some people here that have rebuilt the 7 bolt, and it worked fine, there are others that have done it more then once, and even replaced with another 7bolt, and it crankwalked again!

All those statement are true IMO.
check this for more "info"

Mosty people consider having a 6bolt engine with 2G pistons the best of both worlds. It's the most popular build option here by far.

I am going in that route...

 

[robs90tsi]

I got a rebuilt 6-bolt, and so far I have no complaints, but this issue has been disputed many times, each motor has their benefits, faults, whatever. The ideal 4G63 would be one that combined the best of both versions, 6-bolt with 2G pistons, thats it, thats what I would want for mine, but once again its just my own opinion.

 

[95blackGsTurbo]

Crankwalk is becoming a thing of the past. It usually will happen before 100k miles. And there aren't a whole lot of unmodded cars with awy under 100k miles anymore. I say once you hit 80k miles crankwalk is no longer an issue. These cars are getting old and eventually it won't be an issue at all.

 

[knighteclipse1]

I have questions on weather or not the 7 bolt crankwalk is "rare". I have a 96 Talon in my front yard with that "rare" problem. Thank God my Eclipse hasn't gone the same way...It isn't incredibly common, but it is far from rare. There have been hundreds of threads on this very subject, you should do some searches.

 

[Spoolin4Ever]

I have questions on weather or not the 7 bolt crankwalk is "rare". I have a 96 Talon in my front yard with that "rare" problem. Thank God my Eclipse hasn't gone the same way...It isn't incredibly common, but it is far from rare. There have been hundreds of threads on this very subject, you should do some searches.

It's extremely rare for those 2g owners that have never had it happen to them.

For some reason they get defensive whenever it comes up.

Frankly I would rather know the truth, then have someone just trying to talk me into a 7 bolt just cause they have one that hasn't crankwalked.

 

[Turbo Talon 111]

crankwalk in 7 bolts is actually more rare than most people think. its one of those things where you only hear about it when it is a problem. all the times its not a problem you never hear anything. so for all the cases that were actually crankwalk (not misdiagnosed) there are a lot more that don't get reported. take mine for example. 142,xxx miles and no crankwalk. had 2 problems that could have been misdiagnosed as it though. (clutch and crank sensor issues). on top of that i still have 178 psi in all cylinders. tell me now how a 7 bolt is not reliable. and no i'm not being defensive i'm just telling how it is.

and crankwalk can be perminantly prevented. i don't remember the specifics and can't find the link that tells about it but if you don't take my word for it then call them.
http://www.gatewaydsm.org/SpeedDesign/index.html

these are also from GDSM

Yeah and also all of the MAIN CAPS casted together rather than a 1g only has 2 MAINS that are casted together, so basically the 2g engine has a main girdle which makes the mains alot stronger. Most big cubic inch race motors that people build they install main girdles to make the lower end stronger and to handle the high rpms and keep from blowing the mains and crank out the bottom of the engine.


Actually if i was going to build another daily driver 1g or 2g and I was going to keep hp under 500 I would use a 7-bolt. They have an eight pund lighter rotating assembly. If you remove the balance shafts (10 pounds) and you lighten the flywheel (9 pounds) you have a rotating mass 27 pounds lighter then a stock 1g. granted you can lighten a stock 6 bolt flywheel and take the balance shafts out. But 27 pounds lighter then Factory is a bunch. That is 2-3 tenths in the 1/4. but that is just me


don't get me wrong though, the 6 bolt is still a good engine. just ditching it because of misconceptions is plain wrong.

 

[1meanGSX]

Very imformative information Turbo Talon, I never knew some of that. Brings a whole new perspective on 7bolt engines.

 

[Steve_P]

Ok, the reason you want to go 6 bolt is because they have more of an advantageto the 7 bolts. My 1990 Talon TSI AWD of course has the 6 bolt..........compression on it has 130 with brand new headgasket. My 95 Talon TSI AWD has a compression of 180 with brand new headgasket. The 6 bolts have a lot lower compression. That is why you can put unleaded fuel in the 1g 6 bolts. Being that you only have 130 compression with a new head gasket, you can turbo up the boost making the engine push out more air.......meaning an increase in compression. You can get strong 7 bolts, but when you want to raise the boost on them, your risking a lot, the compression on the 7 bolts it quite high the way it is compared to the 6 bolts. The 6 bolts are definelty to anybody's advantage.

130 is low for a cranking compression test for a 1g turbo. I believe the spec for new is ~160. Check the service manual specs.

 

[alex]

I'm one of the founders of Highline Motorsports and I have probley owned between my brother and I over 30 DSMs. I would say out of all the cars, we only have had 3 or 4 of them "crankwalk". But we buy most of these cars already crankwalked for cheap and fix them up and sell them. So really, "crankwalking" does happen but isnt as big as an issue that everyone says it is.

The 1st gens 6 bolts are a nice build up car for racing, while the 2nd gens are good daily drivers. They both have there advantages and disadvantages.

 

[EvolvingGST]

Sigh crank walk is rare... My eclipse died after 140k because it jumped time. Totally different from crank walk. Its like the same statement that DSMs are unreliable.

It is just what people do to their cars.. I never had issues with my DSM except for this freak accident. The cam angle sensor went into the cam gears, causing it to jump time. Someone tell me how that happens?

Anyways... Don't listen to most of these people, notice most who say it have 1Gs. and as alex said its not as common as many people say and they have owned like 30. I currently own 4 .

 

[PaulN]

Ok, the reason you want to go 6 bolt is because they have more of an advantageto the 7 bolts. My 1990 Talon TSI AWD of course has the 6 bolt..........compression on it has 130 with brand new headgasket. My 95 Talon TSI AWD has a compression of 180 with brand new headgasket. The 6 bolts have a lot lower compression. That is why you can put unleaded fuel in the 1g 6 bolts. Being that you only have 130 compression with a new head gasket, you can turbo up the boost making the engine push out more air.......meaning an increase in compression. You can get strong 7 bolts, but when you want to raise the boost on them, your risking a lot, the compression on the 7 bolts it quite high the way it is compared to the 6 bolts. The 6 bolts are definelty to anybody's advantage.

I see your in Wisconsin, pm me if your interested. I have a couple 6 bolts laying around.

If your 90 Talon only has 130 compression, you're nearing a rebuild! Mine has 155 across the board and 165 is factory stock specs.

None of the above has anything to do with why people want a 6 bolt over a 7 bolt and a lot of it is just plain old misinformation. The main reason people switch to a 6 bolt is to pretty much to try and avoid crankwalk or their engine has crank walked or it just blew and they hive this crankwalkaphobia since it's supposedly prevelant in a 7 bolt..

If compression was the issue (or even an issue), why then do so many people put 2G pistons on 1G rods in a 6 bolt engine? WTF They do it to get the added benefit of the low end torque of the 2G pistons and faster turbo spool time.

Also, higher compression requires less boost to make the same amount of power, with all things being equal.

Finally, Both engines run on unleaded fuel, so I am not sure what the heck you mean by you can use unleaded fuel in the 6Bolt and for that matter both are rcommended to be running premium grade fuel, 91 or above octane.

 

[knighteclipse1]

It's extremely rare for those 2g owners that have never had it happen to them.

For some reason they get defensive whenever it comes up.

Frankly I would rather know the truth, then have someone just trying to talk me into a 7 bolt just cause they have one that hasn't crankwalked.

It wasn't my intension to say it is rare or it was something that happens frequently, I was just stating that it does still happen on occasion to some people.

 

[92DSMErdrick]

Just go with a 1g 7bolt if your going to have to use a 7bolt. It's very interesting that the likely hood of a 1g 7bolt to crankwalk is less than a 2g 7bolt considering 1g are older motors on the streets.

 

[m3th0d]

Hi guys,
I own 2g 7 bolt and let me tell you, it has over 150,000 miles on it. I doubt it will ever be a problem in the future. If anything, I think my engine will go out and I will never expirience crankwalk.