now the question is who did their sleeves and have they had any problems with them.

 

Just fyi, I talked to Kyle and Mark at length at SEMA and they have cut the stock sleeves in half and actually tested the material. They are confident that the stock sleeves are good to 900whp+, and they said that someone may actually prove they are even stronger. As said before, SGP and Z1 have torn down a number of VQ's and could make money re-sleeving them all, but don't think it is necessary.

While we are asking for pics, can someone from AEBS post pics of the hairline fracture in the stock sleeves?

 

aebs. and if they do have problems with the sleeves, they're in trouble cause they had about half the world's supply of vq's sleeved for their drag racing program. these guys don't **** around.

yes i know aebs has had many problems with the engines they've built and will continue to do so, that's just the nature of the business. but i reiterate my assertion that the people who think that the vq sleeves will sink have never even seen them.

and 900hp on stock sleeves? for how long? i'm not saying they'll crack at 450hp, but they won't last long at 900 either. and why would they cut the stock sleeves in half? to find out they are aluminum w/ an iron liner? a fact which everybody already knows and has already been pointed out on this thread, without having to cut the sleeves.

 

ALL sleeves are like that. Every company in the world that sleeves motors makes them in the same fashion that you spoke of, with a lip/shelf area for the sleeve to sit on a part of the stock sleeve that is left in place just for that purpose.

The AEBS sleeves for the VQ look exactly like the AEBS sleeves for every other motor that they make sleeves for. The problem is that the sleeves still have an interference fit with the part of the stock sleeve that is left for them to sit on. That interference fit makes them very hard to press into the block, and the sleeve can stop pressing in before it bottoms out fully where it is supposed to. Then under load and heat, the expansion of the metal allows the sleeve to finally drop to where it's supposed to be, and voila, you have a sunk sleeve.

ANY resleeved motor can have this kind of problem. It's one of the risks you take when doing this kind of stuff.

As for stock sleeves cracking at a certain power level... It's absolutely assinine that people still think of a HP number being the cause of a blown engine. Your stock sleeves will handle ANYTHING and EVERYTHING you throw at them EXCEPT for two things. Detonation, and hydro-lock. Tune it right, and you have no worries.

Detonation, pre-ignition, knock, ping, whatever you want to call it, is the ONLY thing (aside from hydro-lock) that can create enough cylinder pressure to crack a stock sleeve.

 

Thats a pretty bold statement. I just want to find out as much as possible so please dont take these questions as a rebuttal to your post.

Can you explain why so many companies make after market sleeves for Honda and Nissan aluminum motors? Under the same load, heat, and expantion of the metal, cant the stock sleeves weaken over time? Just so everyone reading this also knows, aluminum melts at around 900F while Iron melts at around 2100F. The inner half of the stock sleeves are cast iron while the outer half is aluminum. These 2 halfs are tightly fitted and im curious to what type of process is involved. But IMO, which is limited, i can see how the 2 different materials can expand at different rates under high loads, heat, and seperate from each other due to aluminum expanding twice the rate of iron. http://www.engineeringtoolbox.com/20_358.html
I remember reading that open deck sleeves designs are a result of easier and cheaper manufacturing processes, so this would explain why the sleeves are a 2 piece design instead of a solid cast iron sleeve.

 

Well, in the honda world, sleeves are a necessity for a high output engine. These guys are making upwards of 800hp from sleeved 1.9L engines, and I've seen upwards of 600 from sleeved 1.6L engines. Are they a necessity for a light 350hp build? No, not at all, but most of the honda kids who slap a turbo onto a stock engine end up cracking their sleeves from detonation, or from really intense side loads induced by a bad rod ratio at 9500rpm... This trend has made everyone think that the stock sleeves are weak, and so everyone replaces them.

There is also a LOT of money to be made selling sleeves in the honda market, so the manufacturers recommend sleeving the motors for each and every forced induction build.

The truth is that in the honda world, all that is needed for a 500hp engine is a block guard and some forged internals. Of course, the block guard install can be botched, resulting in cracked sleeves, so everyone thinks they are no good...

The VQ35 block has the same support cast into it that a block guard in a honda engine gives you. About halfway up the sleeve, in the water jacket area, where the side loads from the pistons are going to be. You don't have to worry about your sleeves shifting at high rpm, because they have this support. That is why I said that only detonation or hydro-lock would crack a VQ sleeve.

So we know that the VQ block has been cast in such a way to get rid of one of the causes for cracked sleeves. All that's left to do damage is detonation, or hydro-lock. What every engine builder in the world knows is that a good running engine making extreme power without detonation, will never build the kind of cylinder pressures it takes to crack a sleeve, but the cylinder pressures that you get with detonation increase exponentially, and that's when they crack.

Think about it. A twin turbo supra engine has been known to hold together for years and years at the 1000rwhp level, but the first chance that it detonates at WOT, it's toast. Interestingly enough, that same engine can be toast from detonation, even if it has only been making 450rwhp. So what caused the engine to break? It wasn't the power output, it was bad tuning that led to detonation.

Every blown engine that I have ever seen, has been caused by detonation, not a hp number. Now, keep in mind that your tuning needs to be better to resist detonation with higher power output. That's just the nature of the beast. With more power, you need to get better at resisting detonation to keep an engine together.

As for the melting point of aluminum, remember that aluminum engines are not straight aluminum. It's an aluminum alloy. If it is the same alloy that pistons are made of, then it melts around 1650 F, or 900 C.

I think it is POSSIBLE for stock sleeves to separate, but engines have been made this way for a long time, and I have never seen ONE case where this has happened. I don't think it's a concern.

Your sleeves CAN weaken over time, this is true. Will they weaken after 3 years at the 800rwhp level with no detonation? I don't think so. Will light detonation in an 800rwhp engine weaken them over time? Absolutely.

I don't know if I covered everything you asked or not. I just wrote a book, and don't feel like going back to read it all Feel free to ask again if I missed something. This is a subject of great interest to me, since it happens to deal with one of the few things in this world that I love...

 

Nice write up I really appreciate you taking the time. I actually learned something today!

Yeeha!

 

Thank you very much for a wonderful post.

Az

 

i love this forum!!

 

that was very educational...keep it coming!!!

 

Supra motors are cast iron and not Aluminum so they dont have sleeves.

 

Tell that to someone who has had to resleeve an iron block.

The point was that it isn't a horsepower number that causes things to break...

 

Im not sure who im tring to convince any more. I agree that even 800 rwhp probably wont break the sleeves if everything is perfectly tuned, but how long will that last in the real world. One bad tank of gas or the motor runs a bit too hot for a few seconds. The whole argument by AEBS and my shop is that longevity is at question. I mean, AEBS developed a stroker kit for cring out loud, they must know what their doing! What i really would like to know is what are the causes for the sleeves to weaken over time.

 

well I would say you were stupid if you ran 800whp all the time. Thats the beauty of turbos. You can turn down the boost when you want too or turn it up when you want too. If your using the e-manage. Just makes 2 maps. one for low boost and one for high boost. Problem solved.

 

even w/o detonation the unsupported cylinders will walk and distort out of round w/ that much hp.

 

The guys at AEBS are good friends of mine, and they do know what they are doing. They know very well what they are doing. They are making money. You have to remember that they have a product to sell, and they are not going to lead you to believe that their product is not needed.

That would be true in an engine with unsupported sleeves, such as a honda engine. The VQ sleeves are supported, and like I've said before, it isn't a hp number that causes sleeves to walk. Extremely high rpms cause that, but that's a moot point, because the VQ sleeves can't walk.

 

Mind if you PM me your name and who you know at AEBS?

So your saying that there is no longevity issue with sleeves running 700 rwhp as long as there is no detonation?

And thanx for sharing this stuff with us.