Enron Exec

I was just wondering how would our motors, once built, handle under track conditions with alot of FI. By alot I guess im talking about the 600-700 rwhp most are aiming for running 15 minute sprints around a track in 95 degree heat. My main worry is the VQ35DE's aluminum block will not be as resiliant to heat soak as a cast iron block's. Even when properly tuned, plus the addition of a larger radiator and oil cooler, will it be likely we will ever see a built FI VQ35DE run on tracks all day or go for top speed record runs?

Chi-TownWarrior

iTrader: (3)

Thats a good question, and it deserves a good answer........ j/k

From what I've read Ferrari, Renault, BMW use AL blocks in their race cars, and they seem to hold up just fine, concidering there is literaly billions of $ spent on R/D. Granted nobody has spent that much on our Zs. If you count in regular maintenance such and such, a built block should beable to last (even racecars).

Was the VG30 block AL?.

A friend of mine back in IL had a built 300 and he tracked that car every weekend till his wife made him sell it (poor thing). The block was good to go, he never complaind about it. He even ripped it down every now and then to see how his parts were holding up

Just my .02

Enron Exec

Those 3 auto makers are almost exclusively NA as far as production cars. I think Renault has a hand full of mildly boost V6s. What kind of motors are they racing with?

The VG30 was cast iron. My engine builder has built countless 700+ rwhp 300ZXs. Many of them are still running at over 100k miles. This is going to be the first VQ35DE hes built I think. Im scared...

Chi-TownWarrior

iTrader: (3)

IMO when you get to that level of performance boost or no boost engine wear should be close, If not the same. Just IMO. Don't be scurrd , from the little reading I've done on the site the VQ block tolerances are pretty good. Add sleeves, and you'll be good to go.

Last I read since F1 is imposing the new 1 engine rule Renault is concidering throwing the wide angle V10 idea. I might be wrong thoe.

Anyone else???

Chi-TownWarrior

iTrader: (3)

I'm an idiot, Boosted blocks wear more then non boosted. My bad.

ImportPartsPro

iTrader: (512)

Who is your engine builder? There are only a handful of 700+ Rwhp VG30's and we have built 3 out of the 6 I know of.

Should have brought it to us to build...we are local and we have built 10+ VQ35's now

Chi-TownWarrior

iTrader: (3)

I don't mean to hijack your thread
Can you post any info on thoes VQs you built?, and how are the blocks holding up?. I know thats there probably not enough time to tell, but any ideas?

ImportPartsPro

iTrader: (512)

No problems so far. We have built 3 that are doing 550+ Rwhp on a daily basis and have not had any problems what so ever.

Enron Exec

Tom at Lightspeed. Im not sure if they are all running 700+ rwhp but with the right parts and tunning they are probably capable of it.

I would have but you guys are always so busy! Plus im getting a few discounts from Tom.

Both are great shops from what i hear, you really cant lose going either way. Ive met Fred and his green monster of a 300zx that you guys built.

ImportPartsPro

iTrader: (512)

Well discounts are great if you don't have problems . I have heard the red convert 350z they did the guy sold the car because he was having so many problems . And that was just a simple Greddy turbo kit.

Oh well....good luck. And you are correct we are very busy for a reason . Plus just FYI we have core VQ35 motors that we could have built for you while you continued to drive your car instead of waiting while your motor is pulled.

Z1 Performance

iTrader: (564)

Do not compare what blocks in F1 are made of..those motors are torn down between races and new ones are fitted for the next events.

As for this block, I doubt anyone will be able to give you much insight yet as no one has hit that power level on this motor with any sort of sustained use.

basam350z

iTrader: (1)

Why resleeve the VQ35 when it already comes with Cast Iron Sleeves?

Enron Exec

I was shocked that the red vert was up for sale almost 2 weeks after it rolled out. From what ive heard, the car was never tested and tuned. The owner wanted it out in like 3 days or something and that kit had one of those long wastegate bolts that didnt fit or something.

I kinda flooded my engine so ehhh..... But thanx for the offer. I already miss driving my car.

Sharif@Forged

iTrader: (92)

The VQ uses an open deck design, so even though they have cast iron sleeves, the open deck introduces significant weakness into the mix. I have no doubt that the stock block deisgn can take big WHP...many have already proved this. I just question the longevity of the motor....and if the stock sleeves will last for 75-100K miles.

Enron, to answer your orginal question. If you are concerned, I would just sleeve it and solve all your problems. Nobody has long term experience with these blocks, so take some precautions..that would be my suggestion. Of course, the reason the F1 guys use aluminum is for weigh savings. AL blocks are half the weight...if not lighter...than a comparble iron block. This is also the reason many OEM's use AL blocks. Ligher weight means more effective power on the road, and better fuel mileage...all things being equal.

shopdog

Aluminum is a *much* better conductor of heat than cast iron. So the block should operate at a more uniform temperature than a cast iron one, and reject heat to the cooling water better too. The open deck design also helps, providing more cooling to the top part of the sleeves, where heat is greatest, and more cooling to the heads, where the danger of warping is greatest.

shopdog

The sleeves are located by clamping pressure between the head and the lower block recess which retains the bottom ends of the sleeves. That's true even in closed deck designs. Aluminum expands much more than cast iron with increasing temperature, so sleeves in closed deck engines would also be loose if they depended on the block deck to locate them at operating temperature.

There is relatively little lateral stress on the outer block walls, which would be strengthened by a closed deck, so there's really little, if any, advantage to a closed deck design. And there is a big disadvantage to a closed deck, poorer cooling of the upper part of the sleeves, where the majority of the heat in the engine is generated.

phunk

iTrader: (21)

i would not be recommending that people just go out and sleeve their blocks just yet.

we need some sleeved blocks out there proving it.

in the honda world, block sleeving is a requirement, and also a huge risk. Too many sleeve jobs get screwed up and cause horrible head gasket problems as the sleeves sink.

I want to see some sleeved blocks on the road proving that our currently available sleeve installers are doing it right.

Sharif@Forged

iTrader: (92)

True, installing sleeves is a rare art. That's why I'd recommend having Darton install them directly. They have done this hundreds of times...maybe not on a VQ....but they have the expertise to get it right.

Shopdog, unless my high school physics is failing me, iron is a much better conducter of heat than aluminum. That is why...for instance, if you put a piece of aluminum foil in the oven and touch it, it is hot...but not super hot. Do the same thing with a case iron skillet and you will have a 3rd degree burn in about 2 seconds.

Regarding the closed deck. Darton sells a closed deck that has some cooling jackets in it...I forgot what it's called...mid design or semi closed..or whatever. Point is that coolant can still circulate around the sleeve, and that is the design I prefer.

Second, there is signficant lateral force on the cylinder walls as RPM and pressure increase. The pistons are not moving perfectly up and down inside the cylinders, they are actuallly rocking slightly side by side, caused by the force of the rods moving around the crank. This can cause the cylinders to walk and wooble...and with enough force..break.

Chi-TownWarrior

iTrader: (3)

GQ

Do you have a idea on the cost of having darton install sleevs?.

Chi-TownWarrior

iTrader: (3)

GQ, Shopdog

Say the temp of the oven is 230 both elements approach the temperature at some exponential rate, Al's line is slower than Fe so as the both level out trying to reach 230 both at t= infinity. But since Fe (iron) is faster it will always be hotter, more at first less at the end. Iron would be less likely to warp also because it has a much higher melting point so it would warp a lot less at those high temps.