hi power VH45

Post by **Bart ristuccia** » Tue Jan 21, 2003 10:39 am

Just wondering how much hp can the vh45 hold with twin turbos forged pistons rods etc, would 1000hp be out of the question?

Post by **Q45tech** » Tue Jan 21, 2003 10:39 am

Generally doubling the torque to say 600 lb/feet is possible and 480 lb/ft at 6900 rpm might yield 630 HP.

The problem is using 14-15 psi of boost heat the air by 150F or more so the density drops requiring more boost which just makes it worse if you were willing to use Methanol?

Aluminum blocks heads must be designed from the get go to tolerate more than 700-750 HP for any length of time.

Not to say you can't - just rebuilding every month gets expensive!

Post by **maxnix** » Tue Jan 21, 2003 10:39 am

Wasn't there some mention by Q45tech of the inadaquacy of the size of the cooling passages in the head to dissipate the increased heat? Would this perhaps be the limiting factor, regardless of modifications?

Post by **Bart ristuccia** » Tue Jan 21, 2003 10:39 am

What if a good size intercooler is used say 40in long by 30 by 5in wide and methanol do you think the inlet temps would be at a safer level to allow close to 1000hp?

Post by **PalmerWMD** » Tue Jan 21, 2003 10:39 am

Bart,

Check out this VH45DE thread in our Z forum:

http://www.nissaninfiniticlub....11033

Fred...

Post by **Q45tech** » Tue Jan 21, 2003 10:39 am

If an engine produces 300HP at atmosperic pressure, 600 requires 14.7 psi of boost, and 900HP neeeds 29.4 psi of boost.30 psi of boost will raise the temperature by at least 300F.......even if you dropped the charge temp by 150F you would still have a density loss of 15% requiring an extra 3 psi after intercooler say 5 psi before----- just for 900HP ~~ 35psi????

No intercooler can lower that amount of heat, even one the full frontal width on the car, because the the air flow is so low at low speeds [big fans] alcohol/water injection [freon spray on intercooler] would be requiredEven EIGHT 550 cc injectors [stock 370 cc] can only flow enough gasoline to make 110 x 8 x 0.8=704 HP and METHANOL requires almost DOUBLE the flow for same power. 16 BIG injectors?

If I wanted 1000 HP I would start with a 500 cubic inch engine not a 274 cubic inch one.

Post by **Mayhem_J30** » Tue Jan 21, 2003 10:39 am

some Z guys are running 700cc injectors..those could be used to get ya a lil closer

Post by **maxnix** » Tue Jan 21, 2003 10:39 am

I see melting pistons.

Post by **Bart ristuccia** » Tue Jan 21, 2003 10:39 am

to q45tech are you familiar with the RB30 turbo, whats the max hp could one get out of this motor?

Regarding the VH45 Oil squirters for the pistons?Around 850cc/1000cc injectors?Do you have any other suggestions on how to keep the heat down at a stable temp at 30-35psi? Perhaps large aluninium radiator to keep water temp down? Higher flow water and oil pump, oil cooler, thermo fans? Along with large intercooler and methanol? The reason i dont want to go 500ci is to keep the car road legal, in Sydney Australia i cant go over 4.5 liters forced induction for the weight of my car which is around 1150kg.

Post by **maxnix** » Tue Jan 21, 2003 10:39 am

Quote »i cant go over 4.5 liters forced induction for the weight of my car which is around 1150kg.[/quote] Bolt-on some then unbolt it after it is weighed by the gendarmes.

It should fly for many miles with a stock VH45DE at that weight.

Post by **Q45tech** » Tue Jan 21, 2003 10:39 am

You got me! I'm sure anything can be done but my racing expertise stops 150 HP per liter [675 HP] and 15 psi intercooled.

SR20/2.4/3.0 and special 3.3 V6

[8] 1000 cc injectors with Methanol wouldn't make 1000 HP

Post by **Bart ristuccia** » Tue Jan 21, 2003 10:39 am

I found an RB30 turbo that put out 764hp at 30psi and peaked at over 800hp with 40psi but that was stretching it alot as it was close to breaking.

Post by **Q45tech** » Tue Jan 21, 2003 10:39 am

Inline 6 are more harmonically [crankshaft] stable than V8.......V6 are the worst of the bunch other than 2.5 liter and over I4 [can you say need for balance shafts].

If you want EXTREME high HP and RPM /supercharged V12 or I6 is the only way to go.

Post by **maxnix** » Tue Jan 21, 2003 10:39 am

Quote »If you want EXTREME high HP and RPM /supercharged V12 or I6 is the only way to go.[/quote] While 60° V12s (and I think 120° v12s) have no primary imbalances, neither do 180° V6s (Porsche) nor V12s (Boxers).

Post by **Bart ristuccia** » Tue Jan 21, 2003 10:39 am

I want to thank q45tech for your advice and help. Just saw the chaingiude kit and the cost of it scared the **** out of me $448 US which makes it around $900Aus pretty expensive but then again it includes chains, guides etc and crank seal. Q45tech, are the bearings in the camshafts roller bearings, also would it be possible if you could show me the engine specs out of the rapair manual for (rebuilding the engine,VH45) because im thinking of buying an engine in Australia where i live from the wrekers and theres no manual on it here that i know of, i think the Infinity came out here in very limited import 10 years ago and i dont think Nissan here support this car unfortunatly.

Post by **Q45tech** » Tue Jan 21, 2003 10:39 am

Of course the 32 individual cam followers have roller bearings and cost $24.00 EACH US. The 16 sodium filled exhaust valve are only $17.75 each and the special hardened seats are $14.25 and each of the 32 valve guides are $15.25 and each seal is $2.75.4 new cams are $1,000

Just to do a total replacement valve job would run $5,000 in new parts........even with our discount you can see that a total engine rebuild with all new parts on the same block and heads would be cover $10,000 in parts and the same in labor to meet all factory specs .............why used engines are such a deal.

The dealers pay about half of list vs independents 75% of list.

Post by **AGM** » Tue Jan 21, 2003 10:39 am

Bart,

If you are in Sydney, Hornsby Nissan is your official Infiniti dealer.

They are quite helpful and can get you all the Infiniti parts.

Hope this helps!

Regards

AGM

Post by **Bart ristuccia** » Tue Jan 21, 2003 10:39 am

Thanks AGM it helps alot.Q45tech how would i ID a VH45 from a VH41 where would the ID numbers be on the block if any, thinking about it for a sec i guess there would have to be one of some description but sometimes the engine ID (engine capacity) is mixed with other numbers.

Post by **Q45tech** » Tue Jan 21, 2003 10:39 am

Most of the 41 have straight low tech log type exhaust headers vs the 45 with what looks like real curved headers.Measure the stroke 3.256" vs 2.99" through a spark plug hole?

Post by **Bart ristuccia** » Tue Jan 21, 2003 10:39 am

What material should i use for the (custom) turbo manifolds for a VH45, 304 grade stainless steel or steam pipe, what would you suggest, ive read stainless can be more brittle but that doesnt worry me too much because the manifold can be braced for extra strength, stainless manifold if designed properly can have a performance advantage as it holds heat more effectivly increasing exhaust flow apparently. Would factory rings and bearings (big ends and mains) be sufficiant for over 600hp, and the sodium valves or would i have to go aftermarket parts, my plan is to have an engine thats reliable and not a grenade, is reliability possible with this combination or am i dreaming?

Post by **Q45tech** » Tue Jan 21, 2003 10:39 am

By design to keep cost down yet allow 7300 rpm the rods are the weakest light link {but they are stronger than you think but not 600 HP STRONG]! Study piston speed and weight/strength. I wouldn't worry about the 90-93 block [you will have to o ring the block and heats as the oem gasket is not designed for extra pressure.

The problem with pistons is custom ones will be forged and thus rock in bores when cold [as the expansion rates of forged is greater].

Building a 600HP reliable engine that could last 100,000 miles will be expensive. No one does that they build for power and rebuild every year or run.

I have a friend who builds 2.0 and 2.4 Nissan engines for racers [for years his shop was NISMO USA and he was/is backlogged 2 years and employs 9 engineers and a dozen techs]......these $10,000 upgraded blocks and heads don't last at 400 HP but they win races

The bearing area is small for 600 HP so you must change bearing often.

You are years away from worrying about things like stainless vs iron headers..........getting titanium rods is the first order of business, then pistons and having ring designed and custom built, finding someone to redo the heads [flowbench].....the ports will stall at 450 HP and boost will be wasted heating the air.The intake runners are tuned for 4,000 rpm 3 rd harmonic so a whole new intake runner/plenum will need to be designed.

For reliabilty you must run the absolute LOWEST boost possible which means attention to wastefulness in airflow.

The problem will be the backup of heat restriction of turbo not sure the sodium valves nor valve guides will like 600 HP for long.........everything was designed to last a very long time at an average of 30 HP with 300 HP used rarely.

Post by **Bart ristuccia** » Tue Jan 21, 2003 10:39 am

So shorter intake runners are needed? say 7-8inches for 7000rpm.I was thinking using carillo rods i was quoted $5100aus $2500US,but i can get titanium rods for about the same price here in Australia so titanium would be the way to go? JE, Cosworth, Arias so many to choose from.

Post by **Bart ristuccia** » Tue Jan 21, 2003 10:39 am

Q45Tech

So shorter intake runners are needed? say 7-8inches for 7000rpm.I was thinking using carillo rods i was quoted $5100aus $2500US,but i can get titanium rods for about the same price here in Australia so titanium would be the way to go? JE, Cosworth, Arias so many to choose from. I guess an after market engine management computer would have to be used. Are you familiar with Haltech? i actually just started working for them, their computers seem pretty good in terms of tuning accuracy in there fuel and ignition maps.

Post by **maxnix** » Tue Jan 21, 2003 10:39 am

http://www.haltech.com

I predict Q45tech will have a sleepless night or two with this manual by his bedside.

Thanks. Funny how there seems to be so much more innovation in Australia than the US.

Post by **Q45tech** » Tue Jan 21, 2003 10:39 am

An ecu is an ecu..........new OBD2 is much more complicated than any tuners product.

Have worked on V12 engines where every cylinder had its own ecu, as each cylinder was 100% adjustable and monitored......12 knock/pressure sensors [in spark plugs] and 12 ExTempSensor and 12 - O2 sensors.

Tuning out the errors that creep in, cylinder to cylinder variances, at different rpms can add significant power and durability to racing engines.

That's the problem with so called "tuner chips" they were dyno created way back when on just one test engine............so they are nowhere near optimized for another engine...........sure probably better than Safety First oem programming but still 5-7% less than optimum[just on the ragged edge of exploding/melting].

Post by **maxnix** » Tue Jan 21, 2003 10:39 am

Oh cutting edge it is not, but flexible it is as it can be programmed via a PC. If it has the ability to interface with the G50 sensors, plus any necessary additions for pressurized intake, then this could be a path to safely upgrade the VH45DE a little.

Don't have a BSEE, nor the knowledge required to evaluate it in that application. To my novice eyes, it does seem to have some possible potential. I just don't know.

Post by **Q45tech** » Tue Jan 21, 2003 10:39 am

Programming WOT and idle is easy. It's the decel and cruise and lift off decel and cold start warmup that the difficult part.

WOT takes a few hours the other stuff takes the [day in day out] months/years of trial and error.

What would be great is to have a factory ecu for the normal stuff and a Super ecu for WOT..................this is what OBD2 does.......many are so smart that you can supercharge lightly [20% or 3.0 psi] without changing a thing as the MAF has extra range.

Why the 5 psi radial superchargers are so easily adapted to engines......a rising full pressure regulator ranging up to 75 psi and you are done.........but 5 psi nets only 33% less drive losses /air density drops say 20% more peak HP and 8% more peak torque

Post by **maxnix** » Tue Jan 21, 2003 10:39 am

Nice manual with the Haltech. I wonder if someone has the stock or JWT maps somewhere?

Post by **Bart ristuccia** » Tue Jan 21, 2003 10:39 am

Whats JWT?

Post by **PalmerWMD** » Tue Jan 21, 2003 10:39 am

Jim Wolfe technology.

The "chip" guys with the largest amount of experience with Nissan/Infiniti.

Fred...

hi power VH45

hi power VH45

Cooling passages?

Vh45

RB's

Lead Ballast

No first order imbalances

To q45tech

Hornsby Dealer

Q for Q45tech

VH45

VH45

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