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Help with new motor build

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bizie

Proven Member
129
3
Jul 17, 2014
hagerstown, Maryland
So I just got a 6 bolt and I'm looking for some specific information on what exactly the numbers on the build sheet mean. This is a brand new block built by Rob Fig? apparently he is a know name is the dsm world? I don't know because I'm new to all of this. I mainly want to know what exactly does .40 over mean? I know it is the bore being .40 over but then what would the displacement of the block be? It is on a stock crank and I'm just now learning about changing the crank for different displacement also, so I'm getting confused about how you get to a 2.3 liter? Is it by boring the cylinders or is it by changing the crank? So if I am .40 over am I a 2.4l? Sorry if this is a dumb question but aren't they all when you know the answer?

Also wanted to know if this means I need a special head gasket size? Do I go with the 85.5mm head gasket? I have 9.0:1 Compression ration cp pistons. Does this effect the head gasket I need?

For now this is all the noob questions I have but I'm sure I will come up with more since I still have to complete the block assembly and get it into my 2g gst. Thanks guys for any help.
 
It is .040 or 1mm over std bore of 85mm or 3.346
.40 over would be about a 10mm over bore and take you to a 95mm bore.

Boring the block is not going to gain you much displacement, around 2 CID

The 2.3 is built by 100mm stroke crank in a 85mm bore block
The 2.4 is built by 100 mm stroke crank in a 86mm bore block

the stroke on a stock crank is 88mm

I wont get into rod lengths....

The Stock bore HG will be just fine, you will know it is too small if you set it on the block and the gasket hangs over into the block bore.

If you have rods and pistons at this point, you are already decided on what stroke crank will be used in the build. if your rods and pistons are for a 2.0 build with a 88mm stroke crank and all you do is swap to a 100mm crank, the crown of the pistons will poke out the top of the block and HG and bang the head. On the flip side of the coin, if you have rods and pistons for a 2.3 "stroker" build and you use a 88mm stroke crank, the piston crown will be well below the block deck and you will not make enough compression for the engine to run.
 
That helped a lot man. Thanks a ton.

So I basically have a 2.0 or a 2.03 ?

I have bc stock length rods. The pistons are already in the block but that's it.

The ultimate question is if boring increases hp or torque or is it just something to refresh the bore?
 
By my math you have a 2044.69 cc engine now or a 2.045L

124.8 cid now with the bore, and stock is 121.8 cid, so a gain of 3 cid

So if you make 2hp per cubic inch (121.8) is 243.6 with an increase of 3ci you will gain 6hp.

Boring a block will give you a slight increase in HP/torque but not as much as you would hope.

It is more to ensure a round bore and good ring seal.
 
So my new question is about my balance shaft...It is deleted in the engine but I want this engine to be fast and reliable so I would like a balance shaft. The only problem is the only thing I can find is a RACE balance shaft, which is fine for me but I am only wondering if the fact that the balance shaft parts are obsolete will make me unable to install the race balance shaft. To be honest I don't even know what a balance shaft looks like so for me installing one on this engine is going to be tricky. Any help is much appreciated!
 
Nice man. You're a plethora of knowledge. So I see no stubby shaft with my block I bought. So I'm going to get the race shaft since it seems like what I'm looking for.

You've been very helpful.

So yesterday I found a 95 awd tsi with the rear lsd and a full 97 eclipse body mod for $1800. It was near me and couldn't pass it up the guy claimed that the car was getting a 6 bolt swap and being built by...wait for it...Rob Fig, and he wasn't doing the job fast enough or wasn't doing it at all, I don't really know nor care, but what matters is they took their car back and finished the build themselves. Well it sure shows to me because everything looks like a afterthought. The wiring is terrible and it looks like they just tossed the block in there with no planning. The guys (brothers) never put the water pump pulley on and it seems like the clearance is very tight. Is it normal for the water pump pulley to be a little closer to the frame rails after the 6 bolt swap on a 2g? I know that on my 2g I own there is much more room but it has a 7 bolt. Regardless of the clearance I will have to lift the block slightly just to get the pulleys on the water pump. Why they would do that is beyond me. They claimed the car only needed tuned but upon further inspection its obvious that the build needs finished before a tune can even be attempted. There is open vac lines everywhere and gauges dangling. He even has rtv at every throttle body gasket, I don't know if that's acceptable but I wouldn't do it. The guy claimed to be a mechanic but if he is then he knows nothing at all about forced induction.

Thank you for your time bogusSVO
 
What are your goals for the car. Hp wise and are you dd it or will it be a track only. Keeping the bs is not a bad idea to keep your oil pressure up and makes your oil pump last longer. Not sure if anybody sells a oem bs kit or not.
 
With the race shaft, you will not run the front shaft, the race shaft helps stabilize the oil pump gears is all,

You will also have to check the block to see if the rear BS bearing is installed.
 
if you read all the handy tech notes at jacks transmissions site he mentions keeping the balance shafts actually help you shift at high rpm!
I never remove them anymore
 
I would like to hit 500 hp with this build. I have the dsmlink v3 and some fic850cc with a t3/t4 70trim turbo. I will get the lsd and anything else I need. I also currently run bc 272 and plan on using those. I think after reading through svo's links I may rebuild the valve trane. The car is going to be a daily driver and I don't like braking down. I would like a fairly reliable 500hp. I think I am going to put it on a awd platform but I have yet to find a rust free awd lsd car on the east coast. I've looked at four so far and own two but want zero rust for this build.

So I have a feeling that for reliability you guys are hinting at me using the OE balance shaft setup..

And YES I must shift at high rpm smoothly!

I dont have the bearing or a short shaft, nothing in there.

So I am off in search of a oe balance shaft and bearing I suppose.
 
Wait, is there two balance shafts? Oh crap, I need to read more... SMH
 
Yes two balance shafts come in the engine from the factory, one behind the oil pump and one on the other side. They are about a foot long each.
 
Yes 2 balance shafts, My finger is at the front BS, lower right, is the oil pump gear drive snout, behind the castle plug is the bolt that holds the rear balance shaft in place, and stabilizes the the oil pump gears.

The second pic shows both shafts and how they pass thu the front case.
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i havent run my engine, yet, but i think the AMS race shaft is a good option. its what id did with mine, and i feel it should alleviate an oil pump issues as far as longevity.

lots of ppl do the stub shaft option, and have no issues. if you are good buddies with a machinist, you can have the rear shaft turned down (not hardened) for next to nothing (what i did) and have the same product essentially as AMS's for a fraction of the cost.

honestly, if your motor is already built, then id leave it as is, unless youre super worried about it.
 
I cant seem to find oem balance shafts so I think I'm going to get a race shaft and then the other shaft can stay off, right?

Thanks for the pic svo, that is very helpful.

I need to learn how to work this forum better...I just saw a message that svo has the oem shafts for me! Even cheaper then the race shafts. Longevity and high rev shifting here I come. Shoot, with the amount of power I am going for I'm sure I wont notice the difference in the balance shafts being there. I do like their purpose and feel it will reduce vibration through the whole drive shaft.
 
On another note, I got my awd talon going (white car is gst eclipse) and I can hear a tapping noise coming from the clutch area. I now it's this area because when I press the clutch pedal a bunch it sometimes goes away, then if I keep pressing it I can get it to come back. The guy I bought it from said he put a 6 puck in there with a fidanza light weight. I'm thinking its not torqued right...?
 
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