[stekki]

Is this done or not? Will the cylinder wall be OK to drop in the new pistons with lower compression? Ultimately I would like the BOE nikasil block but this will maybe be overkill for a street car? (And budget wise a no-go at the moment).
Goal is to upgrade to REV400 in the future

Thoughts?

 

[Deja Vu]

No way to know until you've got the motor opened up. The millage is irrelevant, conditional of the walls is all that matters. Odds are it won't be any issue and for a street car really even if they are messed up you'll just have worse compression then optimal, but guess what? It would be the same condition as you are currently driving. �� I would make sure you do the rods as well if you are going rev 400 in the future. Also if you decide you are going to lower your compression I've got a set of new still in the box mahle 9:1 that are from a newer batch which addresses a minor design flaw in the way old stock.

Jeff

 

[turbophil]

...I would make sure you do the rods as well...

Really? Why's that?

-Phil

 

[Deja Vu]

Cause if he's going for your rev 400 kit and is going to be in there anyway it makes sense. Of course were it me I would think, if my plan is to make it a street monster, and I already feel I need to replace pistons, I'd rather just save up and go with the nikasil fully built block and call it done. Less time spent, better engine block, and great support if there are problems.

Suppose I should have said "While you are in there might as well do the rods as well."

 

[turbophil]

Understood. FWIW- the stock 2ZZ rods are good parts (1ZZ rods are junk, FWIW). Unless you're just wanting to spend money to spend money, that's a grand that doesn't really need to be spent...

-Phil

 

[Deja Vu]

That's good to know. Over on the Celica forums I've seen a bunch of claims that they are no good after about 260lbs torque and 360hp or so. (which in this case should mean you'd be ok without even if they are correct, but I do tend to play that cautious though)

Since you've got way more experience than random internet kids, would there be a point where new upgraded rods are more than playing it safe and instead are necessary?

 

[turbophil]

We've got a lot of experience running motors to about 400whp in street, AX, and track conditions--- under those circumstances, the stock rods are fine. If detonating, anything can break of course, but normal combustion, at those power levels, I've not seen one let go. My car runs stock rods for instance. It lives primarily between 7,000 and 8500 just fine.

Don't have experience running above those power levels, so can't really comment beyond that.

-Phil

 

[Deja Vu]

Cool, thanks for taking the time out to answer. To the OP, apologies for the temporary hijack.

 

[RichardNHCooper]

I dropped Mahle 10.5s in my stock block at about 45,000 km all was fine with the Rev 400 for another 40,000 until crazy me added NOS and did not retard the ignition. All compressions were perfect but for the cylinder that did a piston ring.
In OZ the guys run full race setup with the standard MMC bores without any issues.

 

[stekki]

Guys, thanks for those replies . Is it a straight swap with the new pistons? Does my tune require an adaptation for it? How much will 10.5.1 influence detonating?
My car is a weekend-toy and never sees a track. So I guess Nikasil coating would be overkill then.

 

[addertooth]

Stekki,
Do you mean "How much will 10.5.1 influence detonating?" while normally aspirated, OR, how will it affect the engine with a REV400. It is a drop in compression for a stock normally aspirated (NA) engine, so I suspect it will get you some extra safety margin. Let Phil know your compression when you get a REV 400, this way he can give you the right tune for the kit.

 

[stekki]

Addertooth, thanks for chiming in . My car has already the REV300 package, was just thinking to add the safety margin to my current setup. At the moment I have the smaller pulley that is not default in the REV300 setup. It will certainly help when the other upgrades arrive too.

 

[holmz]

... I would make sure you do the rods as well if you are going rev 400 in the future.

Really? Why's that?

-Phil

...Cause if he's going for your rev 400 kit and is going to be in there anyway it makes sense...

This makes as much sense as the first statement...
It is a circular argument to say "I would change them", and because it makes sense.
Why exactly does it make sense?

...Over on the Celica forums I've seen a bunch of claims...

I doubt ^those guys^ support their claims with fact.

Addertooth, thanks for chiming in . My car has already the REV300 package, was just thinking to add the safety margin to my current setup. At the moment I have the smaller pulley that is not default in the REV300 setup. It will certainly help when the other upgrades arrive too.

I am not sure about a safety margin, but at the same boost level 9:1 will make less milage than 10.5:1 , and usually less power too unless you really have to pull the timing.

Usually one starts off with octane and works backwards with boost to compression ratio.

 

[stekki]

Other question, how long does it take to pull head etc so one can inspect the cylinderwalls? 1 hour, 2 hours, half a day?

 

[glagola1]

Your time frame questions are basically impossible to answer. The fact that you're asking them makes me think that you have little experience doing such tasks. The fact that you have little experience makes me think things will take longer with you because things always take longer the first time.

I'm worried that you are planning on digging this deep into the car with such little experience and that you'll be renting a space to do it. You don't want to rush these tasks. You'll probably run into a lot of little snags along the way and need various tools or parts you don't have. You'll be feeling the pressure of a rented space deadline and that's bad for the intended outcome.

I'd recommend finding a place where you can take your time.

 

[Westrock]

I do as much of the work as possible on my car by myself. Car has never been to a dealership or a mechanic for normal repairs, and I have removed the engine.

But when it comes to separating the head and block and working on the rotating assembly, I leave that to the professionals. It's is the most crucial part of the construction of the engine in regards to clearances as well as the timing aspect between top and bottom. Do yourself a favor and pay someone experienced to do it. The first time I had [email protected] work on the engine I sent him the whole engine and he took it all apart and put it all back together and the price for just that part of the labor was like $300-$500, but I want to say closer to $300. Well worth it in my mind.