turning the crank a bad idea?

[supra_kid101]

I recently bought my first turbo supra a 89 targa 5spd with rod knock. I've heard getting the cranked turned is a bad idea and proves not very reliable. I'm wanting 450hp out of the car so i'd really prefer to not screw it up really soon. Does turning the crank make it weaker and less reliable?

 

[Dunckel]

Kinda confused here, but it's late. When you say "turning the crank", do you mean having it balanced?

 

[IJ.]

10/10 is fine any more and it needs to be rehardened.

 

[supra_kid101]

10/10 is fine any more and it needs to be rehardened.

thats what the machinest says he's going to try to get it to...im not sure exactly what that means though

 

[IJ.]

He means he's going to grind 10 thou of an inch off the diameter of the Rod and Main bearing journals giving you a 10/10 undersize crank that he'll supply the correct set of 10/10 bearings for after installing them in your rods and block and grinding the crank to suit

 

[supra_kid101]

He means he's going to grind 10 thou of an inch off the diameter of the Rod and Main bearing journals giving you a 10/10 undersize crank that he'll supply the correct set of 10/10 bearings for after installing them in your rods and block and grinding the crank to suit

oh ok that makes sense...i was confused by this all day long...thanks for the information
:icon_razz

 

[IJ.]

Good idea to have the rods resized while it's apart it's had 15+ years of abuse (maybe even treat em to a new set of ARP bolts)

 

[supra_kid101]

Good idea to have the rods resized while it's apart it's had 15+ years of abuse (maybe even treat em to a new set of ARP bolts)

I've actually ordered ARP rod bolts and from what ive been told by the machinest the rods that were in it are from Eagle. They are getting resized as well. The machinest sold me a crank, .40 oversize pistons (brand new in box), and .40 overbore block for $220.00. Some guy had the work done over a year ago and never paid for it.

 

[IJ.]

Whoo hoo nice pickup
(can't think of anything on my car that cost $200 )

 

[supra_kid101]

Whoo hoo nice pickup
(can't think of anything on my car that cost $200 )

Lol i'm hoping my car will eventually reach that caliber. I was so excited when the guy sold me that stuff. Now my only problem is I can't for the life of me find .40 overbore piston rings. I've found .30 and .40 though lol

 

[IJ.]

What brand are the pistons?

 

[supra_kid101]

What brand are the pistons?

I meant .30 and .50 and they are Nippon I believe.

 

[IJ.]

Ok you need to make 100% sure what size you have here

.5 is usually Metric ie: +20 thou (1mm = 40 thou roughly)

But you may have +40 thou pistons (+1mm so 84mm)

The rings should be easily available.

 

[supra_kid101]

Ok you need to make 100% sure what size you have here

.5 is usually Metric ie: +20 thou (1mm = 40 thou roughly)

But you may have +40 thou pistons (+1mm so 84mm)

The rings should be easily available.

I'll check the box for the exact sizes tommorrow when I pick up them up.

 

[IJ.]

Get your machinist to measure them to be 100% sure .

 

[7MsuprO]

Yea, machinist should be able to get you some or point you in the right direction. .40 over isn't an uncommon size.

 

[WhtMa71]

I like hastings rings. http://www.hastingsmfg.com/oem.htm

 

[suprarich]

I've actually ordered ARP rod bolts and from what ive been told by the machinest the rods that were in it are from Eagle. They are getting resized as well. The machinest sold me a crank, .40 oversize pistons (brand new in box), and .40 overbore block for $220.00. Some guy had the work done over a year ago and never paid for it.

Are you saying that you have Eagle rods in your block now? If so, and you purchased some ARP rod bolts for the stock rods, they will not work as they are two different styles and size of rod bolts.

 

[supra_kid101]

Are you saying that you have Eagle rods in your block now? If so, and you purchased some ARP rod bolts for the stock rods, they will not work as they are two different styles and size of rod bolts.

Damn that sucks haha. At the time of ordering I assumed they were stock rods.

 

[Motofool]

every eagle rod ive ever ordered in the last 5 years came with arp 2000 rod bolts from the get go, congrats you have bought your first set of parts you dont need or cant use, Welcome to the performance industry.

on another note if your buying rings seperate from the pistons you want to check the end gap on them. if you put the piston ring in the cylinder bore atleast .5" down the bore make sure it is the same distance down from all sides, and use some thickness guages(there is another name for these i cant remember right now) and make sure are not too big or too small(stick the guages in the gap of the ring). too tight can be bad as it can help breaking a ring land under high heat/stress. too loose and u will have blow by or pressure in your crankcase that you dont want cause its not staying in your combustion chamber.

your machinist should know all about this but if he doesn't you have a general idea whats going on.