2g 4g63t engine options

[Iowa99GST]

So, I bought my 99 GST last march (09), the motor blew up a month later -_- It has been sitting in my driveway for the last year now and I'm really getting sick of the down feeling every time I get home and remember that my beloved 2nd gen is right there but not drivable . I don't really have 100% of the financing I will probably need to get her running the way I want her to again, but I'm wanting to start getting stuff together piece by piece (this wasn't a daily, so I have time to save up/buy stuff part by part)

I'm not a mechanic, and I don't know a LOT about working on cars myself, and I also don't have a lot of time to work on my car with a 9 month old and a full time job , so I'm looking for suggestions here.

Before my engine blew, I was pushing around 21 pounds of boost with a small 16g turbo that spooled up amazingly (I was in love ) and I don't think anything is wrong with anything BUT the engine. I threw a rod (bottom end is junk, hole in the front and back of the block) and I was told by a shop that I "Obliterated" one of the cylinders.

So, to the point, my question is, what do you guys recommend for a new set up? I obviously need a new block and head so I am looking at just replacing the whole engine at once, but idk if I should go with something like a bushur RACING block, find a used 7 bolt and rebuilt it with performance parts, or even possibly find a used 6 bolt and have it rebuilt with performance parts?

I don't have unlimited resources, so buying an already built block IMO is almost not an option, unless you guys know of somewhere that sells good racing blocks for a decent price, and from what I understand the 6 bolt swap doesn't just drop right in, there is actually quite a bit of modification needed, is this true? Or was I mis-informed..

I have also seen stuff about using a 2g block with a 1g head and so forth, what do you guys think would be best?? I'm not looking for anything crazy like 45 pounds of boost or a 9 second car, I'm just lookin to build something that is going to be pretty fast for not TOO much money.

Thanks for all of your help!

 

[XiKeiyaZI]

So, I bought my 99 GST last march (09), the motor blew up a month later -_- It has been sitting in my driveway for the last year now and I'm really getting sick of the down feeling every time I get home and remember that my beloved 2nd gen is right there but not drivable . I don't really have 100% of the financing I will probably need to get her running the way I want her to again, but I'm wanting to start getting stuff together piece by piece (this wasn't a daily, so I have time to save up/buy stuff part by part)

I'm not a mechanic, and I don't know a LOT about working on cars myself, and I also don't have a lot of time to work on my car with a 9 month old and a full time job , so I'm looking for suggestions here.

Before my engine blew, I was pushing around 21 pounds of boost with a small 16g turbo that spooled up amazingly (I was in love ) and I don't think anything is wrong with anything BUT the engine. I threw a rod (bottom end is junk, hole in the front and back of the block) and I was told by a shop that I "Obliterated" one of the cylinders.

So, to the point, my question is, what do you guys recommend for a new set up? I obviously need a new block and head so I am looking at just replacing the whole engine at once, but idk if I should go with something like a bushur RACING block, find a used 7 bolt and rebuilt it with performance parts, or even possibly find a used 6 bolt and have it rebuilt with performance parts?

I don't have unlimited resources, so buying an already built block IMO is almost not an option, unless you guys know of somewhere that sells good racing blocks for a decent price, and from what I understand the 6 bolt swap doesn't just drop right in, there is actually quite a bit of modification needed, is this true? Or was I mis-informed..

I have also seen stuff about using a 2g block with a 1g head and so forth, what do you guys think would be best?? I'm not looking for anything crazy like 45 pounds of boost or a 9 second car, I'm just lookin to build something that is going to be pretty fast for not TOO much money.

Thanks for all of your help!

I would say " let's diagnose the issue" ... but you mentioned the hole in the block.

Question : Was your car even tuned to run 21 PSI, or did you just crank it up and go for it?

Tear off the head, find out if it's salvagable. Sometimes they are, sometimes they aren't. It wouldn't hurt. As far as a block... I'm thinking that you can use whatever you damn well please as long as you're willing to do the work. I have spare 6Bolt block sitting in my driveway. 6Bolts are proven to be stronger than 7Bolts. There's a lot of back and forth there, but when it comes down to it, we all know.

Pretty much it's a front to back process. You're going to start with your basics which would be engine first. Then you want to figure out what caused the last engine to fail and build to prevent that. There are plenty of people here letting things go for cheap, and other major retailers who do performance parts for cheap. I've recently purchased from Partsdinosaur and was pleased with everything that was sent.

 

[Iowa99GST]

Well, from what I understand it was a crankwalk issue, I don't think there was anything particular that CAUSED it to happen, I know the 6 bolts are supposed to be better engines and don't have the infamous crankwalk issues, but like I said, will it just drop in? Or would there be a lot of work to make it fit into my 99 gst? Also does a balance shaft delete kit eliminate the crankwalk issue? I've heard that as well but like I said I don't know much about engines >.< Lol, so any info/help would be appreciated.

From what I understand, the car did have the supporting mods to push 21 pounds, it ran AMAZINGLY and when it went, I was pushing like 13 pounds just driving along the highway. I think my problem was that I bought it from someone who had bought it from the guy I originally tried to buy it from like 3 months after , the guy who owned it in that time didn't take very good care of it I'm assuming.

I think the reason he actually sold it was because it was cutting out at mid/high rpms/boost, but when a friend of mine who actually works on cars and I checked it out, it turned out to be that he had put too big of spark plug wires on the car (in my friend's opinion, he had 8mm wires on it) and the plugs were not gaped properly. We did a quick spark plug/wire change on the car and it fixed the problem, also he did a compression test at the time and they were all perfect, he couldn't believe how well they tested, like high 150's-low 160's I think it was (remember this was over a year ago, my memory could be off) and he knew the person who ORIGINALLY owned and modified the car, he said that the car was done right from the beginning and had like $5k into the motor..

I was sad to see it go =(

 

[LiquidX]

Haha, well you are probably going to hate me after hearing all of this...

Well, from what I understand it was a crankwalk issue, I don't think there was anything particular that CAUSED it to happen

Don't say it was creankwalk if you have no idea what crankwalk even is. I can think of a few things that would have caused your engine to blow up, and crankwalk isn't one of them.

I know the 6 bolts are supposed to be better engines and don't have the infamous crankwalk issues, but like I said, will it just drop in? Or would there be a lot of work to make it fit into my 99 gst?

Use the search button for your answers, that's why it's there. You need to modify the motor mounts, use 1g 6bolt parts and 2g parts to mount it up. Need to put on a 1g CAS as well if you go with the 2g head. 1g head will have everything you need assuming it's a full head.

Also does a balance shaft delete kit eliminate the crankwalk issue?

I'm speechless on this WTF. As stated above, don't throw words around that you don't know. Balace shaft elimation kit is just what it is. It elminates the balance shafts and that's all.

From what I understand, the car did have the supporting mods to push 21 pounds, it ran AMAZINGLY and when it went, I was pushing like 13 pounds just driving along the highway

You should know what is in your car and you can't listen to what sellers say to you. All they are trying to do 70% of the time is just get some fool to buy a piece of junk. If you ran 21lbs and the car couldn't handle it, you already did the damage and 13psi is just when it went out.

I think my problem was that I bought it from someone who had bought it from the guy I originally tried to buy it from like 3 months after , the guy who owned it in that time didn't take very good care of it I'm assuming.

So did you even do all required maintenance before driving it and putting money into it? Especially after saying the orgional owner didn't take care of it and the next person prob. didn't either. Did you take it to a garage to get a buyers inspection done?

I think the reason he actually sold it was because it was cutting out at mid/high rpms/boost, but when a friend of mine who actually works on cars and I checked it out, it turned out to be that he had put too big of spark plug wires on the car (in my friend's opinion, he had 8mm wires on it) and the plugs were not gaped properly.

HAHAHAH friend is a half idiot. You can't have too big of plug wires as that is where the current is traveling to the plug wires. Less resistance the better. Now, if the plugs wern't gapped right then yes, you will have cutting issues.

We did a quick spark plug/wire change on the car and it fixed the problem

Apparently you didn't do the required maintence of buying a used car because you should always change the plugs and wires when you get a used car, along with many other things. The wires were either old with breaks in the wires or the spark was jumping through the boot.

lso he did a compression test at the time and they were all perfect, he couldn't believe how well they tested, like high 150's-low 160's I think it was (remember this was over a year ago, my memory could be off) and he knew the person who ORIGINALLY owned and modified the car, he said that the car was done right from the beginning and had like $5k into the motor..

Compression test results from a year ago, why would you rely on that. You want to compression test WHEN or BEFORE you buy the car . It's amazing what people will do on cars to hide problems or cause problems.

5k in the motor ? Where are the recipts of proof and he should have had higher compression that that...

I was sad to see it go =(

Next time, learn about the car before you beat on it and do things you were told it can do. Keep it maintained and read up on this site for all your info before you throw parts at it.

I have a spare 97 7bolt block and head here. PM if interested or PM above for the 6bolt block. Check the classifieds as well for used parts too.

 

[Iowa99GST]

Dude, you didn't read half of what I said did you? The compression tests on that block that blew are a year old, because the engine blew A YEAR AGO, I didn't take his word on what he said it tested a year ago, we tested it a year ago when I bought the car, obviously you can't really put too big of spark plug wires on there but he wasn't sure if those wires were what were causing the problem and that for the set up I had I didn't need to buy 8mm wires again, so I didn't when we replaced the plugs and wires, also I never said the original owner didn't take care of it, he babied it and I wanted to buy it from him ORIGINALLY but I couldn't come up with the money, then the guy he sold it to put it back up for sale a few months later because he was "getting sent to Iraq" Yeah, you can call me dumb for that if you want to but oh well, I bought into that and here I am, I'm still happy with what I have I just want to get it running properly again, and I'm asking people's opinions on what I should put in it because as I openly admitted, I don't know a lot about DSM's myself, so basically what I'm asking is what build is going to be the least expensive but most practical for what I'm looking for (weekend driver, fast but not anything ridiculous like 9 seconds or anything like that). Oh, and also, the whole thing about me not throwing words around unless I know what they mean? I'm pretty sure my motor crankwalked since I threw the rod through the block, and I've heard many different places that the balance shaft eliminator kit solves the crankwalk issue, I was just wanting to know if that was actually true or not which is why I asked about it.

Anyways, thanks for your input on the answers you did give, but I just figured I would try to clarify a little of that since some of your accusations were a bit off there IMO.

 

[LiquidX]

Dude, you didn't read half of what I said did you? The compression tests on that block that blew are a year old, because the engine blew A YEAR AGO, I didn't take his word on what he said it tested a year ago, we tested it a year ago when I bought the car, obviously you can't really put too big of spark plug wires on there but he wasn't sure if those wires were what were causing the problem and that for the set up I had I didn't need to buy 8mm wires again, so I didn't when we replaced the plugs and wires, also I never said the original owner didn't take care of it, he babied it and I wanted to buy it from him ORIGINALLY but I couldn't come up with the money, then the guy he sold it to put it back up for sale a few months later because he was "getting sent to Iraq" Yeah, you can call me dumb for that if you want to but oh well, I bought into that and here I am, I'm still happy with what I have I just want to get it running properly again, and I'm asking people's opinions on what I should put in it because as I openly admitted, I don't know a lot about DSM's myself, so basically what I'm asking is what build is going to be the least expensive but most practical for what I'm looking for (weekend driver, fast but not anything ridiculous like 9 seconds or anything like that). Oh, and also, the whole thing about me not throwing words around unless I know what they mean? I'm pretty sure my motor crankwalked since I threw the rod through the block, and I've heard many different places that the balance shaft eliminator kit solves the crankwalk issue, I was just wanting to know if that was actually true or not which is why I asked about it.

Anyways, thanks for your input on the answers you did give, but I just figured I would try to clarify a little of that since some of your accusations were a bit off there IMO.

I missed the "09" part of "last March" I thought it was this past March. Ok, so it was the 2nd owner that didn't take care of it. The guy you bought it from correct?

Crankwalk = http://www.dsmtuners.com/forums/articles-engine-fuel/342560-crankwalk-depth-explanation.html

I don't blame you for not being happy with it, I haven't driven mine for about a year and a half now for multiple reasons.

It's good you want opionions and I wasn't calling you stupid or anything just incase you got that impressions. We all start out somewhere. The best thing you can do as stated is do as much reading about these cars as possible so you get an idea of what it is. The 6 bolt has less issues with CW overall, but CW is over rated. A built 7 bolt shouldn't have issues either. The 7 bolt will drop right in where as the 6 bolt will need modifications to fit.

The BSEK just removes 2 balance shafts, increases oil pressure and gets rid of a belt.

A stock rebuild can get you a quick car. 6 bolt rods can handle about 400hp 7bolt rods do about 350 being smaller.

 

[XiKeiyaZI]

I missed the "09" part of "last March" I thought it was this past March. Ok, so it was the 2nd owner that didn't take care of it. The guy you bought it from correct?

Crankwalk = http://www.dsmtuners.com/forums/articles-engine-fuel/342560-crankwalk-depth-explanation.html

I don't blame you for not being happy with it, I haven't driven mine for about a year and a half now for multiple reasons.

It's good you want opionions and I wasn't calling you stupid or anything just incase you got that impressions. We all start out somewhere. The best thing you can do as stated is do as much reading about these cars as possible so you get an idea of what it is. The 6 bolt has less issues with CW overall, but CW is over rated. A built 7 bolt shouldn't have issues either. The 7 bolt will drop right in where as the 6 bolt will need modifications to fit.

The BSEK just removes 2 balance shafts, increases oil pressure and gets rid of a belt.

A stock rebuild can get you a quick car. 6 bolt rods can handle about 400hp 7bolt rods do about 350 being smaller.

Don't forget to mention that the BSE causes you to FEEL more engine vibration. You do not CAUSE more vibration, you just feel more.

That's the reason they are called Balance Shafts.

But yes, do not take a sellers word on anything. Test everything out for yourself before you buy. If I were you, I'd have gotten the car, turned the boost down, at least changed T-Belts, fluids, plugs and wires, filters, and everything else.
Then would confirm the supporting mods and whatnot before turning the boost back up.

But yeah.. honestly.. =/ form the sound of it, I don't think it was built to really handle the 21PSI... sure..it maybe had bigger injectors and whatnot for it..but yeah...you saw what happened first hand. It threw shit OUT of your engine. Too much boost is like pumping NOS into your intake...or 4 bottles of octane booster..

But yeah, there are minor modifications needed for the 6 bolt block which can handle more power. Or a 7 bolt which is also very stable and sturdy. They do have cradles for the caps on the block.. which are suspected to increase the chances of crankwalk... but it's unconfirmed. The 7 bolt is also a drop in with no modifications.

It's your choice. =/

 

[Iowa99GST]

Thank you, your 2nd post was a lot more helpful

So, with that said, if I were to grab a 7 bolt block and a 6 bolt head, what would be the upside to that? I have heard a lot about people doing this but not much about what the benefits are. Also, if I were to take a 7 bolt block and rebuild it with performance parts what would you guys recommend if I were looking for something in the neighborhood of 400hp?

 

[Bender]

Don't forget to mention that the BSE causes you to FEEL more engine vibration. You do not CAUSE more vibration, you just feel more.

I know I'm going to look like a jerk for nit-picking on this, and offer nothing to the OP, but..

Removing the balance shafts does cause more vibration. You are removing the balancing shafts that rotate to counter-act the oil pump. By removing the balancing shafts, you throw the engine out of balance, causing more vibration.

Solid motor mounts on the other hand do cause you to feel more vibration.

 

[XiKeiyaZI]

I know I'm going to look like a jerk for nit-picking on this, and offer nothing to the OP, but..

Removing the balance shafts does cause more vibration. You are removing the balancing shafts that rotate to counter-act the oil pump. By removing the balancing shafts, you throw the engine out of balance, causing more vibration.

Solid motor mounts on the other hand do cause you to feel more vibration.

Not being 'prideful' ... but for informational purposes.. o.o

Balance shafts were put in these engines to reduce the amount of vibration that you feel. They counter-act with the vibration of the engine to give you a smoother ride. Removing them will not cause the engine to vibrate more. You simply feel the vibration that they were dulling out. If it caused more vibration, no one would the BSE, nor would it be so cheap or recommended.

Also to add... removing the BS will increase oil pressure which is a good thing. They also remove just a little bit of rotating mass. Removing these does not "toss the engine" out of balance.. don't you think that'd be a bad thing? =/

Thank you, your 2nd post was a lot more helpful

So, with that said, if I were to grab a 7 bolt block and a 6 bolt head, what would be the upside to that? I have heard a lot about people doing this but not much about what the benefits are. Also, if I were to take a 7 bolt block and rebuild it with performance parts what would you guys recommend if I were looking for something in the neighborhood of 400hp?

Personally...I'm not sure of the benefits of a 6Bolt head on a 7Bolt block. More compression? Just search for it.

What I would do with the 7bolt would be...and these are basics.
BSE - Balance Shaft Elimination
Stronger internals. Or at least 2G Pistons with 1G rods
Build the head tobe a bit stronger. In the least, stronger valve springs.
A clutch package to handle that HP.
Fuel System Upgrade. Injectors, pump, lines, etc.
Intake and Exhaust Upgrade. 3' with no/straight cat and a FMIC upgrade.
Turbo Upgrade. The stock one isn't going to cut it...=/

NOTE : The above mentioned are basic things.. there are still tons of other things to do that can help you acheive your HP goal.

But.. the first thing you want to do... is get yourself the following..
1 : ECMlink
2 : The proper Guages
3 : Wideband

THEN... do the other upgrades.. save for the internals and clutch... do those as you're rebuilding the engine.

EDIT - The below information can be found at - http://www.4g63turbo.com/tech/eclipse-balance-shaft-removal.html

Balance shafts are commonly found in inline four cylinder engines such as the Mitsubishi 4G63 which, due to the asymmetry of their design, have an inherent second order vibration (vibrating at twice the engine RPM) which, contrary to popular belief, cannot be eliminated no matter how well the internal components are balanced. This vibration is generated because the movement of the connecting rods in an inline engine is not symmetrical throughout the crankshaft rotation; thus during a given period of crankshaft rotation, the descending and ascending pistons are not always completely opposed in their acceleration, giving rise to a net vertical inertial force twice in each revolution whose intensity increases quadratically with RPM, no matter how closely the components are matched for weight.

The 4G63 found in the Mitsubishi/DSM turbo Eclipse & Eagle Talon are equipped with 2 balance shafts. The left balance shaft that's directly connected to the oil pump driven gear and the right balance shaft that's driven by the balance shaft belt over the oil pump sprocket. Two balance shafts rotate in opposite directions at twice engine speed. Equally sized eccentric weights on these shafts are sized and phased so that the inertial reaction to their counter-rotation cancels out in the horizontal plane, but adds in the vertical plane, giving a net force equal to but 180 degrees out of phase with the undesired second-order vibration of the basic engine, thereby canceling it. The basic problem presented by the concept is adequately supporting and lubricating a part rotating at twice engine speed at the higher RPMs where the second order vibration becomes unacceptable.

So why do it? The main reason for balance shaft elimination should be reliability as power gains are minimal. As you can see it inherits a potent lubrication problem and unlike the name suggests it's job isn't to balance but merely masks off the vibrations. Silent shaft is a more appropriate term but not used as commonly. Although the chances are slim, it's still one less part that can fail.

The good
More HP to the wheels
Zero chance the balance shaft belt will fail and kill the timing belt
Zero chance the balance shaft bearings will fail and damage the rest of the motor
More oil pressure to the rest of the motor

The bad
More vibration is felt in side the car (no more is made, just more is felt)
More oil pressure to the rest of the motor, which is usually too much. Extra work to get the oil pressure back in spec.

 

[XiKeiyaZI]

Any update? All going well?

 

[96mitsugsx]

If you don't have a lot of money to spare, just get a used 7 bolt bolt block and have it and the head rebuilt . A stock 4g63 motor can pretty much handle your s16g. Since you're not mechanically inclined, you're going to spend at least 1.5k before you get your car back on the road.

 

[Bender]

Not being 'prideful' ... but for informational purposes.. o.o

Balance shafts were put in these engines to reduce the amount of vibration that you feel. They counter-act with the vibration of the engine to give you a smoother ride. Removing them will not cause the engine to vibrate more. You simply feel the vibration that they were dulling out. If it caused more vibration, no one would the BSE, nor would it be so cheap or recommended.

Also to add... removing the BS will increase oil pressure which is a good thing. They also remove just a little bit of rotating mass. Removing these does not "toss the engine" out of balance.. don't you think that'd be a bad thing? =/

The balancing shafts counteract the vibrations that engine would normally cause. I think we are saying the same thing, just differing views on what counts as the "motor." The pistons, rods, crank, etc are still making the same amount vibration. The balancing shafts do help you not feel those vibrations by counteracting it. I consider the motor the whole long block assembly, whereas without a counterbalance, there will be more vibration. So yes, you feel the vibration that was there, because you have nothing countering it.

Also, too much oil pressure is a bad thing. You will need to put a restrictor inline with your turbo (even journal bearings) to keep the seals from popping. PTE turbos are especially known to do this, because their seals are only rated at 70 psi. On my old 1g, without balancing shafts, cold starts resulted in 120psi oil pressure. A 0.075 restrictor works wonders to save the turbo. Also, you will need to modify your OFH (port it) to help lower the pressure. The higher pressure will also result in more oil in your head, where you will need to modify your HLA regulator, or buy Kevin's.

 

[XiKeiyaZI]

The balancing shafts counteract the vibrations that engine would normally cause. I think we are saying the same thing, just differing views on what counts as the "motor." The pistons, rods, crank, etc are still making the same amount vibration. The balancing shafts do help you not feel those vibrations by counteracting it. I consider the motor the whole long block assembly, whereas without a counterbalance, there will be more vibration. So yes, you feel the vibration that was there, because you have nothing countering it.

Also, too much oil pressure is a bad thing. You will need to put a restrictor inline with your turbo (even journal bearings) to keep the seals from popping. PTE turbos are especially known to do this, because their seals are only rated at 70 psi. On my old 1g, without balancing shafts, cold starts resulted in 120psi oil pressure. A 0.075 restrictor works wonders to save the turbo. Also, you will need to modify your OFH (port it) to help lower the pressure. The higher pressure will also result in more oil in your head, where you will need to modify your HLA regulator, or buy Kevin's.

Haha. I can agree to that. Find common ground - Always the right thing to do. But when it gets down to it, the added FEEL of vibration won't damage the engine. As quoted in my previous post, the Added oil pressure is a double-edged sword.

You get more oil pressure! Which is always nice.
The downside? You get... more oil pressure... in which will result in the above stated per Bender explained.

Those are about the only downsides to the BSE.

 

[Iowa99GST]

Any update? All going well?

Well, I've decided to go ahead and buy the engine my friend is selling with a brand new head and a block with a spun bearing for $200.. I figure I can't really go wrong with that , I'll just have to get the crank machined and grab new bearings and tear into everything.. Still haven't been able to figure out what I'm gonna start modifying first though, I know I need to get a turbo timer and a wideband, but Idk what I want to do while I have the engine torn apart yet. It has been suggested that I grab some ARP head studs so the stock ones don't stretch, so I'll probably pick those up, and I still need to figure out what I can salvage out of my old engine, or what was even done to it once we tear that apart.

So not too much to update yet, I'm hoping it will all come together.. but like I said, I'm planning on taking my time on this and having it done by next spring to bring the car back out =D I'll get pics of the gst up soon.

 

[Planckscale]

Well, I've decided to go ahead and buy the engine my friend is selling with a brand new head and a block with a spun bearing for $200.. I figure I can't really go wrong with that , I'll just have to get the crank machined and grab new bearings and tear into everything.. Still haven't been able to figure out what I'm gonna start modifying first though, I know I need to get a turbo timer and a wideband, but Idk what I want to do while I have the engine torn apart yet. It has been suggested that I grab some ARP head studs so the stock ones don't stretch, so I'll probably pick those up, and I still need to figure out what I can salvage out of my old engine, or what was even done to it once we tear that apart.

So not too much to update yet, I'm hoping it will all come together.. but like I said, I'm planning on taking my time on this and having it done by next spring to bring the car back out =D I'll get pics of the gst up soon.

Let me give you a moral support...

You do sound like you have been doing your home work, only the practical side is missing. Most of us started by just liking the car, but when we got into it we became mechanics! Having been through four engines, I can honestly say that there is nothing in this car that I don't know or I cannot fix.

Part of owning a DSM is the willingness to do at least 50% of the work yourself. From the sound of it, you seem ready to get your hands dirty. And with it comes a great satisfaction. Also, the car will be broken (not drivable) at least 50% of the time, but when it drives you will forgive yourself for having bought it in the first place.

You're somehow lucky that parts are now much cheaper (thanks to the Internet). Please do search and find out which parts "are must have" and which are "nice to have". For example, turbo timer is not an important part to put money on right now, especially if you don't leave right off a major high way...

Good luck

 

[wkmitsu]

A stock rebuild can get you a quick car. 6 bolt rods can handle about 400hp 7bolt rods do about 350 being smaller.

The 7 bolt rods can handle more than 350hp.

YouTube - 99gst_racer's dyno video. 403 WHP!

If you actually go to youtube and watch this, you'll see in the description that he says he's on the stock 7 bolt block and head (including the cams) in this video.

 

[Guzman08]

i know someone who is selling a 4g63 engine that came out of a 97 eclipse pretty cheap. but not sure how much the shipping would be. the old owner threw a engine in their with less miles. pm me if your interested.

and its not an ad, so please dont give me a warning. just letting the op know if he needs one.

 

[PieEyedPiper]

The 7 bolt rods can handle more than 350hp.

YouTube - 99gst_racer's dyno video. 403 WHP!

If you actually go to youtube and watch this, you'll see in the description that he says he's on the stock 7 bolt block and head (including the cams) in this video.

The 7 bolt rods have held 500whp. So what? 350-400 is about the end of the reliability spectrum. Did you see the pictures of what those stock rods from Paul's car look like today? It aint pretty.

I've spoken to shops who have tested 6 bolt rods vs 7 bolt rods and they all seem to indicate that 7 bolt rods start to visibly bend/wobble etc at 300whp, 6 bolt rods at 350whp and that seems in line with the idea that you can't either of the rods through much more power than around 400 before you're looking at a complete failure.

 

[wkmitsu]

The 7 bolt rods have held 500whp. So what? 350-400 is about the end of the reliability spectrum. Did you see the pictures of what those stock rods from Paul's car look like today? It aint pretty.

I've spoken to shops who have tested 6 bolt rods vs 7 bolt rods and they all seem to indicate that 7 bolt rods start to visibly bend/wobble etc at 300whp, 6 bolt rods at 350whp and that seems in line with the idea that you can't either of the rods through much more power than around 400 before you're looking at a complete failure.

Yeah I've seen what the rods look like now.

I wasn't really taking reliability into consideration, so yeah, good point. But my argument was that they can and have held more. I guess whether or not you want to throw more at them than 300-350 hp is totally arbitrary.