400-450HP Engine rebuild questions/opinions?

[kylefoto]

Alright,
So I've got the upper half of my engine apart (Head is off, oil pan as well, got it flipped over on a stand right now.)
I'm going to be aiming for 450 hp at the VERY most.

My question to you guys is, what should I be using?
Stock pistons?
Rods?
ARP?

In addition to that,
What would you suggest doing with the machine shop, IE, having them take apart and put back together the whole bottom end, what to have them machine, blueprinting (what is blueprinting anyways), balancing, what to make sure to have them do, what they know?
What should I be looking at price wise if I just have them do the machine work and I put everything back together?

 

[Mrbaboon]

Stock pistons will/should hold that kind of power as long as they are in good shape.

ARP hardware is a general must (you can get away without arp main studs and rod bolts, only really if rods are new though).

Keep rods stock as long as they are in GOOD shape. I got brand new ones for cheap so I'm running those.

For machining work, balancing is highly suggested (IMO required). Give them your crank, harmonic balancer, flywheel and pressure plate and your machinist will make it all spin nice and smooth.

Engine builders here at my workplace have told me that unless you are planning to rev the engine higher than stock redline (8 or 9k), you will waste your money doing blueprinting. Toyota did not blueprint from the factory so taking it to stock redline only really requires a stock machined engine.

We have a baffled oil plan, so knife edging the crank, while providing benefits to those running crazy motors, will not make much of a difference for a low-mid 400 build.

I had my machinist assemble the bottom end due to lack of clean garage space for assembly. If you dont have somewhere that is extremely organized and free of all airborn contaminants, then feel free to do it yourself if you are confident in your ablilities as a mechanic.

EDIT: Tell them to chase your head bolt/stud threads, unless you own a good tap and die set or feel like buying one.

 

[kylefoto]

Stock pistons will/should hold that kind of power as long as they are in good shape.

ARP hardware is a general must (you can get away without arp main studs and rod bolts, only really if rods are new though).

Keep rods stock as long as they are in GOOD shape. I got brand new ones for cheap so I'm running those.

For machining work, balancing is highly suggested (IMO required). Give them your crank, harmonic balancer, flywheel and pressure plate and your machinist will make it all spin nice and smooth.

Engine builders here at my workplace have told me that unless you are planning to rev the engine higher than stock redline (8 or 9k), you will waste your money doing blueprinting. Toyota did not blueprint from the factory so taking it to stock redline only really requires a stock machined engine.

We have a baffled oil plan, so knife edging the crank, while providing benefits to those running crazy motors, will not make much of a difference for a low-mid 400 build.

I had my machinist assemble the bottom end due to lack of clean garage space for assembly. If you dont have somewhere that is extremely organized and free of all airborn contaminants, then feel free to do it yourself if you are confident in your ablilities as a mechanic.

EDIT: Tell them to chase your head bolt/stud threads, unless you own a good tap and die set or feel like buying one.

Thank you for all the info!
I'll probably have them reassemble the bottom end, I don't have a whole lot of space, especially clean space.

Anyone else have something to add?

 

[808mkiiisupra]

hmm i always thought toyota blueprinted our engines..hence the numbers for the size of bearings...idk

 

[Mrbaboon]

hmm i always thought toyota blueprinted our engines..hence the numbers for the size of bearings...idk

Unless I am horribly mistaken they didn't, someone else chime in!

 

[Nick M]

Select fit bearings does not equal a blue print.

 

[jdub]

Stock rods should be fine...I would use ARP rod bolts though. Make sure they are re-sized with the ARPs torqued to ARP spec. Rod bearing clearances are critical.

I would also use ARP main bolts...a line hone for the mains w/ ARP bolts torqued is a very good idea.

Meeting the RA spec (at min) for a MHG is a must. Use ARP studs and torque to the ARP spec sheet.

Suggest you read the TRSM on this subject several times

 

[Boostedstr8six]

Select fit bearings does not equal a blue print.

The engine is factory blue printed. It's more than just the bearings. :icon_conf

Have the rods checked for cracks (mag particle) and if they are good see if they can remove the major stress risers. Shot peening is pretty neat too but I don't think it's required here.

I would also decide which bearings you're going to use before you go to the machine shop. The rods and mains have to be machined to match the bearings. If you are going to use the stock pistons you want to put them back where they came from and you don't want to hone the cylinders any more than you have to....do a bit of searching dude. It's been said before much better than I can.

 

[Nick M]

Blue printing the engine is matching cylinders and combustion chambers so they are identical. Factory engines are made on an assembly line, not hand built.

 

[Halsupramk3]

you can destress the rods youself by grinding off the casting flash. then have them shot peened and then have them and all other rotating assebly pieces balanced as mentioned above. remember to give them your timing belt gear too with the balancer so it all can be put together. shot peening is not very expensive and may as well do it. i also put pics of the rods in various stages of polish. you can see the flash which has right angles that are points of stress that can cause a fracture. smooth it out then have them shot peened. the finished shot peened ones look very smooth.

i also ported my head myself. at the bowl and in the ports. you can just remove the lipp of aluminum that is formed when the valve seats are pressed in. it is a slight rough rim under the seat. smooth this out to match the seat and be sure to not cut the seat with the carbide bur. it is pretty easy to do and will help flow a lot. do this before the head is decked and seats cut. i attached a pick of the valve seats as original and smoothed.

arp rod bolts are good insurance and of course head bolts. if you have the cash get main bolts too. with all these steps and those mentioned above you will have an engine that is real close to being able to handle power over what your current goals are. just add forged pistons maybe rods and your there in the future. porting the head more than just the valve seat will also help flow but if you dont do it yourself it would cost money.

 

[Boostedstr8six]

Blue printing the engine is matching cylinders and combustion chambers so they are identical. Factory engines are made on an assembly line, not hand built.

:nono:


Just for clarification on removing stress risers on the rods; you are actually removing forging laps and not casting flash.

 

[IJ.]

:nono:


Just for clarification on removing stress risers on the rods; you are actually removing forging laps and not casting flash.

Any grinding/sanding need to be done along the beam of the rod and NEVER across the rod.

 

[Halsupramk3]

Originally Posted by Boostedstr8six

Just for clarification on removing stress risers on the rods; you are actually removing forging laps and not casting flash.

Originally Posted by IJ

Any grinding/sanding need to be done along the beam of the rod and NEVER across the rod.

IJ yea i lapp wheeled along the beam. No one told my that but it just seemed the natural way to do it.

Boostedstr8six thanks for the clarification and defenition. My wife uses two or three words every day that i dont know the meaning of. Usually its a word i would be better off not knowing what she meant.

 

[gilberjj]

Any grinding/sanding need to be done along the beam of the rod and NEVER across the rod.

can you clarify please. I'd like to know I have it completely correct!

 

[Halsupramk3]

If i understand correctly you grind with the stone or flap wheel so it cuts or runs down the length of the rod not the width. from top to bottom. i also did not touch the lower cap or the top of the piston end. the stone will run up and down the rod. that way the cutting marks will run down the lenght of the rod. i finished off the rod with i think a 80 grit flap wheel then took them to be shot peened.

 

[IJ.]

Hal: Correct even after it's been sanded/polished there are still micro grooves/marks in the surface and you want these along the rod NOT across it.

If they're across the rod think of the dotted lines in toilet paper and this is how the rod will behave

 

[Adjuster]

Part of the reason rods benefit from "Shot peening" is a reduction of any scratches that would act like dotted lines.

The peening process also relaxes the metal too. (Destresses it from what I understand.)

Stress risers are the point where cracks start. (As IJ noted, you never want them to crack along the dotted line so to speak, especially dotted across the beam of a rod...)