HIGHPSI4
20+ Year Contributor
- 809
- 11
- May 11, 2003
-
Vale,
North Carolina
I used a Cometic 4G64 head gasket on mine and it is overbored 0.040". I have had no problems.
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Are you making a 6 bolt 2.3L or are you wanting to build a 4g64 6 bolt engine?
If you're wanting to build a 4g64, why use a 6 bolt?
I'm building a 4g64 2.4 long rod motor that will handle 800whp and from talking to different people the 4g64 7 bolt cranks even though better than 4g63 cranks aren't as good as the 4g64 6 bolt cranks. Not to mention it's easier and cheaper to get 6 bolt internals than 7 bolt internals.
Can you use that 7 bolt girdle on the 6 bolt block?
Okay I see a few problems here...
1: You can do all that with a 7bolt 4g64 unless you specifically need a 6 bolt.
2: You're going to have a lot of weight removed from your crankshaft. Then you're going to get your crankshaft back and have your rotating assembly balanced. If you have 7 lbs of metal removed from your crankshaft by having it shaved down... How do you expect the machine shop to balance your rotating assembly?
Take the entire rotating assembly (crank, rods, pistons, rings, flywheel, damper) to the machine shop and have it balanced. They will remove/add the amount of metal from the crank that is needed. If you remove 7lbs and then take it to the machine shop... They may need to readd 5 lbs to get the entire assembly balanced for your rods/pistons etc.
Butchering a crankshaft isn't always as good as it sounds.
I honestly don't see you gaining anything from a butcher crankshaft. Yea I've read all about the resistance with the crank "splashing" the oil in the pan, but you will need to build an all out lightweight engine to even make it worth while. Butchering the crankshaft can be beneficial but I don't think it will for the average DSM builder. I've read what Bausher and FFWD say about their knife edged cranks, I've read other sites, and forums about them and how these places promise their cranks can spin 10-12k RPM.
Tell me, is your engine going to spin that high? Is your power range going to extend that high? If your power range is from 3500-8000 RPM then do you feel that $600+ is worth it for an extra lightened crankshaft?
I really think it's just more of a money maker for the average engine builder, with flashy gimmicks than any real benefits.
. I have a hx52(holset version of the gt42r) a straight divided t4 manifold and turbo smim cams I'm trying to get my hands on are fp3x's local shop building my a dogbox and built transfercase too. 7-8 pounds of raotating mass is a lot man. Less mass means less stress to mainly on the bearings which will allow you to rev higher on a 2.4 setup which is my train of thought. I actualy want to run a aluminum rod piston and butchered crank setup but it just seems that everyone I talk to says it's big bucs to fit a set of aluminum rods in a 4g64 block because they're so dam thick on the big end and yo need to notch the block. So I will settle for heavier but a little more reliable steel I beam rods and aluminum pistons and a butchered crank.
I called SBR and I would need .060" over (86.5mm) 4g63 stroker pistons for the 4g64 (std bore) block. I can't seem to find any stroker pistons that are for 86.5mm for a 4g63, and I can't seem to find aftermarket rods that are 156mm. I think I'm looking in the wrong way. I also can't find a DOHC 4g64 cometic MLS head gasket. I see the stock one at Mitsu (MD189436) though.
I have 156mm Rods available. I can also get you an .080 stroker piston. I understand that you already have parts on the way but this is good to keep in mind or your next build.
Oliver
[email protected]
. I got that gasket you ordered me def a good piece. The guys in the holset thread want them because of that raised section in the middle kinda like a knife edge effect when used with a divided manifold. I've been thinking about this for a little while... You know that the crankshaft doesn't exactly sit in the oil. When the engine is running the pump is sucking up the oil so it really isn't even "cutting" through the oil. You would need almost another liter or two to actually make the crank "cut through" the oil.
EDIT: I contacted 2 places who mention they do this "knife edging" and they claim that as they do remove weight from the counter weights, they do drill into them and fill them with a heavier metal to balance it out. Now to do that they need your entire rotating assembly to make it match up to your setup. They can't just edge it, balance it, and then expect you to throw it in your engine without your setup.
I'm just really trying to help understand why the process is such a heavily sought out thing. It really will have no benefit to you or me. Does Shep have a knife edged crank? Should send him an email and ask what he thinks about it. Magnus and FFWD can't show you data sheets, proof, or any real status on any benifit from what I've been able to find.
While doing a google search for "Knife Edge Pros Cons" I was able to read a LOT from other forums, and sites that claim there is no real benefit, and no need to doing it.
/rant/
I can't tell one what to do, and I'm not going to say "don't do it"... just that you understand what I'm saying.
Contacting him won't do anything for me as I've already contacted 2 places who do knife edging, one being a very well named company. Also I am just saying that sending a crank somewhere to have all that work done to it for $650-$750 is a LOT of money that can be used elsewhere especially if you wont see any benefit from it.
No matter what you do, or how you see it you can NOT send off a crank and have it cut, lightened, or balanced without your ENTIRE rotating assembly included in the balancing... It isn't possible... Sure you can do it... but it won't work right! So now you have the cost of having all the work done at FFWD, and then the cost of taking it to a machine shop with your pistons, rods, flywheel, damper, rings, bearings, etc... and having the entire thing balanced as each build weight is different. Look at cost effective vs performance gains.
If you go out and add a lightened flywheel, or rods/pistons to a stock crank your engine will not be balanced properly, same if you go out and add a lightened crank to stock rods/pistons/flywheel. It just doesn't work that way. You may change your rotating mass, but your balance will be off and that is not good if your engine is going to be ran for D/D and high rpm. The harmonics won't be in "tune" if you will.
Sorry if it seems I'm going too deep into this but I'm just trying to make sense of it all for everyone involved.I can't tell one what to do, and I'm not going to say "don't do it"... just that you understand what I'm saying.
I'm also not trying to argue the facts or any type of point with you, you're a very smart guy... I've read a LOT of your posts and I admire your DSM knowledge... Just so you know.
. Want to learn about dsm's mod a car the cheap way then when it breaks you will be able to see what the big wigs tell you 