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Rebuilding motor....

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eclipsegsx93

Probationary Member
13
0
Feb 16, 2004
Jacksonville, Florida
hey im rebuilding my motor in my 93 GSX... there are most like lines in the cyclinder walls so im getting it bored out... i dont have much money but while the motor is out i want to do all the thing with the internals while its out and change the clutch and such... any ideas on what i should do while its out... any help will be appreciated! thanks
 
Make sure you swap (if you don't already have one) in a 6-bolt block while you're doing this - you don't want to walk your newly-rebuilt motor.

Get rid of your balance shaft too.
 
all the internals out of the 7 bolt will go straight in the 6bolt correct? if so ill start looking for a block.. i still will probably get it bored just to make sure the cyclinder walls are really smooth.... also do you knwo of the horsepower gains from boreing the motor out... is it just little or worth it?
 
forgot to add...

Get a new knock and 02 sensor, new gen lifters, oil pump and timing belt components.
 
Originally posted by eclipsegsx93
all the internals out of the 7 bolt will go straight in the 6bolt correct? if so ill start looking for a block.. i still will probably get it bored just to make sure the cyclinder walls are really smooth.... also do you knwo of the horsepower gains from boreing the motor out... is it just little or worth it?
Click to expand...

Scrap the 7 bolt block and crank. The skinny rods can be used, and many have made power with them, but I'd ditch those in favor of the big rods. The 1g pistons can be also salvaged, but if you favor spool, get 2g pistons. It really depends on what your goals are. I like my turbo to make power, so I prefer lower CR's for bigger boost applications. If you're insistent on stock parts and want to make power safely, keep your pistons and get the 1g big rods. This will allow for a bigger tuning window on pump gas and allow for some relatively big power numbers. Get some ARP head studs too.

Here are other random things you're need for this off the top of my head: 6 bolt flywheel and regarding the head studs..you'll have to drill your head stud holes on the head bigger (since the 6 bolt head studs are bigger) or get a 6 bolt head.

Wow, looks like you're going to build a whole new motor. Good luck!
 
1. Use a good machinist, make sure your block is,"square to the world."
2. Use the correct tools for putting the motor together(i.e. NO PLASTI-GAUGE.)
3. Re-read numbers 1 and 2 especially #2.
4. What ever you can afford to do to make it the motor of your dreams.

Boring the block will yield a small amount of power by raising your compression a bit, it mainly is just to get a round hole for the new pistons.
Good luck.:thumb:
 
Originally posted by NOSNUSE
Boring the block will yield a small amount of power by raising your compression a bit...
Click to expand...

*EDIT*

This is true..

here are some other things that raise static CR:

Anything that makes your combustion chamber smaller like - decreasing head volume, thinner head gasket, or the obvious..higher compression pistons.
 
False.

Boring a block yields lower CR. Lower CR yields less power compared to higher CR pistons at the same conditions.


I would like you to explain this one. If you take a motor with flat top pistons you make say 9:1 compression, you take that motor bore it say.030 over you will increase the size of the bore area, the combustion chamber size does not change there for the compression increases.
 
Originally posted by NOSNUSE
False.

Boring a block yields lower CR. Lower CR yields less power compared to higher CR pistons at the same conditions.


I would like you to explain this one. If you take a motor with flat top pistons you make say 9:1 compression, you take that motor bore it say.030 over you will increase the size of the bore area, the combustion chamber size does not change there for the compression increases.
Click to expand...

Ahh, but the combustion chamber size does increase when you bore a block. CR is determined by the relationship between the min and max combustion chamber volumes.

CR=Vmax/Vmin

After doing the math, you will see that with this equation Vmax gets bigger faster than Vmin for increasing bore sizes, hence you get *EDIT* bigger CR when boring the block.
 
why do you have a 95= 7-bolt in a car that came with a 6-bolt? was there comething wrong with it and you swiched? All cars 94 and under have 6-bolt.
 
Actually they switched to the seven bolt sometime during the '92 model year.
 
Originally posted by NOSNUSE
What formula are you using, funny the formula I use to find compression ratio shows that the compression increases if you increase the bore. If you don't believe me go here:
http://www.smokemup.com/auto_math/compression_ratio.php?sid=e629a488bf4d631ddea6820216d1d1c3

Type in the standard bore then one that is .020 over.
Click to expand...

You're absolutely correct. If you read my explanation of the relationship of Vmax and Vmin, you'll see that Vmax does get bigger faster than Vmin and results in bigger CR. I went back and changed my responses above so as to NOT spread misinformation.

Good link BTW!:thumb:
 
Hey it's cool, I wasn't trying to piss anyone off or anything, I help when I can. Glad you like the site, it comes in handy.:thumb:
 
Originally posted by NOSNUSE

2. Use the correct tools for putting the motor together(i.e. NO PLASTI-GAUGE.)
Click to expand...

Elaborate please...because that statement goes against most conventional thinking. How else are you going to measure the "actual" clearances once the caps are installed? If you have another way...enlighten me. :thumb:

By the way, I am aware of the fact that you measure everything before installation to ensure everything is in spec.

Mike
 
Elaborate please...because that statement goes against most conventional thinking. How else are you going to measure the "actual" clearances once the caps are installed? If you have another way...enlighten me.

By the way, I am aware of the fact that you measure everything before installation to ensure everything is in spec.

I mainly put that in there so that people don't put a motor together using nothing but plasti-gauge, there are fine to use once you have measured everyhting correctly(twice at least), they should only be used as a double check item, of course I am just kinda anal about spending lots of money on something only to half a$$ the job.
 
i have all the parts you want, message me. (if you need them)

Read everything you can then make up your mind what YOU want.
 
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