IW STi Forum banner

1 - 20 of 34 Posts

·
Registered
Joined
·
541 Posts
Discussion Starter #1
OK, everyone knows power production is more than displacement or high RPMs. But why is it so easy to extract ridiculous amounts of power from cars like the TT Supra & the Skyline GT-R? After all, their exploits in the hands of tuners, not the factory specs, created the real hype. 1200 hp Skylines? 970 rwhp Supras? Yes. But I don't think it will happen with the new GT-R (even if we get one here), and here's why:

The RB26 and 2JZ engines utilized a little something called a cast iron block. Heavy, yes. But also nuke-proof. Pure brute force. A certain degree of finesse will be required if the R35 GT-R uses a TT version of the new 3.5L VQ series, simply because it's an aluminum block. Aluminum is more brittle, more prone to fatigue cracking, and less temperature-resistant. Don't get me wrong, I know it will be good. But pushing to the limits of extreme turbocharging will require a slightly more conservative approach with the new engine.

Case in point, in case anyone saw the October 2001 issue of Sport Compact Car: The insane Dahlback Golf (a VW Golf hatchback using an Audi cast iron I-5). 45 psi of boost with 10.5:1 compression. 4.5 inch exhaust. A 10,200 RPM redline. TEN 800cc injectors (2 per cylinder). 900 hp from a measly 2.1L.

Nothing much impresses me anymore after that article. But try that with an aluminum block & see what happens... engine go boom.

My $0.02: The new GT-R will kick ass. But I doubt we'll see 4-digit horsepower.

Besides big trucks, which current production cars in the USDM have cast iron blocks?
 

·
Registered
Joined
·
208 Posts
Also remember that the Dalhback "Golf" was a $500,000 one-off vehicle. Not a modified Golf.
 

·
Registered
Joined
·
541 Posts
Discussion Starter #3
No argument there! You can do some crazy things with $500,000.

My point was simply that going to those extremes requires an invincible block. And if you need the strength to do things like that, it's cast iron all the way.
 

·
Registered
Joined
·
208 Posts
I'm not sure I totally agree, but I then again, I have no reason to argue. Rather, I will say that this point while in the off topic forum points to one of the other reasons the STi is so different from the WRX: semi-closed deck cylinder block.
 

·
Registered
Joined
·
99 Posts
The new SVT cobra will be using a cast iron block. If Nissan decides to use the VQ, I'm sure the bump in displacement from 2.6 l in the rb26dett to 3.5 l will account for some of the slack. I also don't think it would be very hard for them to cast a VQ out of cast iron. Ford did it for the new cobra, went from all Al to cast Iron, if nissan has used cast iron before, they can easily do it again. There also exist such a thing as fiber reinforced aluminum blocks. Honda has used them for years in the prelude and in the s2000. There have been plenty of 700 hp H22A's out there, stock block, different internals. Now that's 700 HP out of a fiber reinforced 2.2, imagine what you'd get out of a 3.5! Also, looks like ford is planning on using an all aluminum supercharged 5.4 in the gt-40. I'm sure that it's fiber reinforced also. Aluminum isn't the end of high boost and strength. Cast iron is just cheaper (and heavier).
 

·
Registered
Joined
·
208 Posts
A Guess:

Titanium is damn expensive, engine blocks are large and solid before they bore the cylinder. Maybe that large of a block is just waaaayyyy too cost preclusive? I have a feeling that somehow the manufacture process of the engine block just requires too much in the way of large bits of Ti (with too much waste). Ever notice how most titanium parts are small and already well machined? Another thing about metallurgy is crystal structure. I can imagine that it would be tough to get all that done within the realm of anything not funded by the Dept of Defense.

I have a friend that designs Jet Engines for GE, I'll as him....
 

·
Registered
Joined
·
208 Posts
re wrx/sti seats

From a friend:
Cost is definitely a major concern. Another big difference between TI and aluminum or steel is 'damage tolerance'. TI is high strength but very low in ductility relative to aluminum or steel, so nicks/dents/scratches have a much greater risk of starting cracks that would grow until the part fails. This may also prohibit people from using TI in engine blocs, as the cyclic loading during an engine cycle is quite high(ie, every once in a while passenger car and even race engines get 'cracked blocks', and this problem would be substantially worse in TI). I'm not completely sure though, that's just my best guess.
 

·
Registered
Joined
·
135 Posts
umm, if you guys havent heard the skyline is dead after this years Nür production run of like a 1000 or so. if i knew where i read that id link it, but i think i found it on this forum somewhere

and anyone that thinks that the Skyline will come to the US shores is NUTS no offense. if it was going to it would have around the time of Gran Turismo, that car got so much hype over here, did you hear of it before? i didnt and im a car nut. i wish i was in japan..... its their hotrod HP wars of the 60s overthere now.....
 

·
Registered
Joined
·
541 Posts
Discussion Starter #12
The "Skyline" is already here. It's the Infiniti G35. "GT-R" is simply a trim level of the Skyline range in Japan. I think when they showed the new GT-R concept in Tokyo, they dropped the Skyline name & just called it a GT-R. The latest I've heard is that they're "considering" the production version for international sale...

What we don't know yet is whether it will be powered by a V8 or a TT 3.5L V6. Also I don't think they've decided whether it will be badged as a Nissan or an Infiniti.
 

·
Registered
Joined
·
3,816 Posts
Another thing about Ti is it is hard to work on b/c it is so hard.

In jewelry Ti is nice, but b/c it doesn't bend like gold or silver it is very difficult to put prongs into place. Also it is a bigger pain to polish and shape and engrave into Ti over gold or silver.

I would imagine the same for engines.
 

·
Registered
Joined
·
2 Posts
Just to note to you Superbean_21, I own a 2000 Prelude with the H22A4 2.2L and from everything I've read, whatever crazy turbo power you can get out of it doesn't last very long with a stock, open deck block. Too much cylinder wall rattle under boost more than 6-7 psi.

Besides the fact that no one makes CARB legal turbo conversions, I've been wary of applying boost in any way shape or form to my little 2.2L for fear that down the road those floating cylinder sleeves will spell trouble for my checkbook.
Granted, for anything modified even mildly the H22A has crappy rods and pistons.

This is why Subaru appeals so much to me. And I even get away from FWD! :D

As for the monster modified Japanese sportscars with iron block engines? The tough iron castings are what allow such crazy engine work to even work.
I wonder, though, unless you have gobs of cash and live in an area without emissions checks, how are you going to maintain a 1200HP Japanese supercar?

I love R34 GTR's myself and plan to buy a Motorex import someday. 500HP really ought to do it for me and I doubt I'll have to push the engine all that much.

Nismo would be foolish not to build a special cast iron VQ35-TT motor. Some Australian source mentioned not long ago that the new Nismo modified GTR engine would be able to push 700HP stock. Some creative engine work could net higher HP judging by how powerful the current non-turbo VQ35 V-6's are.

I will be sportscar shopping in a few years. If it isn't an iron block turbo I'm not buying. That should say it all there ;)
 

·
Registered
Joined
·
866 Posts
I did some looking but could only find this:

"Up to 80 per cent of the STi’s all-alloy engine is new compared to the standard turbocharged 2.0 litre four-cam ‘boxer’ unit as fitted to the regular Impreza WRX."

I also found countless mentions of the engine block's reinforced nature.
 

·
Registered
Joined
·
99 Posts
kahn-bb6, a 700hp h22 obviously will not last for everyday, just as a 1200hp rb26dett will not last for every day. both engines built to such extreme levels are for drag use only. I did see an article on signal auto's skyline package that includes a 2.8 stroker kit to reach 700 hp. apparently the company's owner uses one for a daily driver.

Now, as far as the open deck, that is a problem that has been adressed many times, and is easily remedied with a "block guard". I don't know if you've heard of them, but they are an insert that fits around the sleeves at the top of the cylinder, acting as a butress, while maintaining water holes for cooling purposes. They are also very affordable, the only cost would really be labor, unless you pull the head off yourself, and seat it properly.

Turbo's.... GReddy just released turbo kit for the H22, all but the SH i believe, optional FMIC available as well. All of GReddy's turbo kits are smog legal, and come with a california EO # that makes it legal. THey document it all. You got a strong block... put in a block guard, (to be safe) get yourself a GReddy kit with the FMIC, and down the road go for some rods,pistons, knife edged crank, up the boost, and you'll fly!

I've been watching these topics for a while(about the H22a) with my bro. we live together, he gots a '98, with a Greddy cat back, AEM intake, Clutch masters super light Al flywheel, centerforce street disc,w/xtreme pressure plate, neuspeed springs, strut trowerbrace. He's kept an eye on JR supercharger, took an eternity to be ready for shipment, but held off to look @ GReddy know. There kit seems like a good thing, still allows lots of flexibility ...unless you've heard different.
 

·
Registered
Joined
·
2 Posts
A 1200 HP Skyline is in fact a daily driver. Most people tune the engine to like 600 - 800 HPand gain the rest from Nitrous. This is because that is about the limit without major over haul to the internal components of the engine, but a 600 HP DD is scary as hell.
 
1 - 20 of 34 Posts
Top