Have we built the most powerful naturally aspirated Nissan in the world???? Specs. Bore 98mm Stroke 101mm Heads standard VH 41 Bottom end standard Block is VH 41 Crankshaft Denco Camshafts-- special grind Fuel--Methanol Compression ---13:1 E.C.U---Motec M800 Electronic fuel injection Handbuilt I.R. fuel injection Dry sumped Carrillo Rods Roughly 400 cu inch Power: 830 H.P. @ 6000 R.P.M. Torque 680 Ft Lb @ 5800 R.P.M. All work done in New Zealand, if you want one let us know. Engine currently in a Jet sprint boat

Same reply as on that Far Away board:

Interesting, but I think a non-stroker would be better for the street.

No mention of headers, but there must have been some fabricated. Injectors, fuel pump? Cooling would be an issue on street also.

Of course, methanol is not feasible for the street.

If you ever do a gasoline version, please report back.

You are right in that everything for this engine was handbuilt including headers, but we are probably looking under US$40,000 for cost although I would have to do a proper analysis to cost it accurately.You will note the power figures are at low R.P.M. and these moters run like sewing machines at 9000+. We only ran the 400 cu in engine to about 7-7500R.P.M. from memory as the jet unit is limited to about 6000 rpm. It will run fine on high octane gasoline and we would not anticipate much power loss particularly if the engine is being used in a car, as you will be able to use more rpm.

We are building here in N.Z. VH41 sleeved back to 240 cu in (stock car 1/4 mile tracks) with 1x 4 barrel carb, and using the cam angle sensor as a distributor. These engines are producing 500+ H.P. @ 9500 rpm on petrol.

There are also 2 x VH45 in jet boats running twin turbos involved in marathon racing on our rivers. I do not have the performance figures off hand but could probably get them if someone is interested. One of the engines is stock and is I understand running about 15lb boost, the bloke who is racing this engine bought 8 of them and is by trial and error working out how much boost they will handle.The other engine has had extensive modifications and from what I hear is going well.These engines come in from Japan and cost us about US$1000-00 each so you can understand why the first bloke has taken the path he has.

Next week a VH41 (modified) is going on the Dyno and I will be able to tell you more about the performance of this engine when I get the figures. This engine is running an E.C.U and using all stock gear apart from cams and the engine maps.

Perhaps you could give me some specs on the 5.7 Litre Nissan in the Titan truck. We are particularly interested in deck heights, head design and dry weight, rod lengths etc

Why sleeve it to 240 cu. in. rather than destroke it slightly? Cost?

Wonder why VH45DE not used for their more robust lower ends? Too rare down under?

Quite intereseting. The difficult part for the headers would be clearing the LHD steering components. Probably something you don't see very often.

Do any of your custom internals come from Japan?

Don't know, but assume the 5.6L truck engine is a derivative of the open deck VK45DE design. Haven't seen any specifications. All VH are closed deck, and probably bettr suited to what you do. Impul has a bore and stroker kit that takes the VK45DD up to 5.1L, but drops the rpm somewhat.

9K rpm on your VH41DE is remarkable. How many hours between rebuilds?

You must have some big rivers in NZ.
Modified by maxnix at 4:27 PM 4/9/2005

That sounds like a weapon....iv put a VH41 into a 1980 VC SLE comy yeah it just fits with sum carfulmeasurement, mods to sump etc. still in the early stages but its in there.theres no room for stock headers so im making some higher flowing front exiting ones which if im right should give an increase in hp strait off since being one of the ways nissan seems to restrict power . i was playn with twinturbo ideas but the aim is to get it going first. I moved up from nelson 6 months ago,sounds like i moved to the right place huh!

Have sent you an e-mail as you lve about 45 mins from me

Have sent you an e-mail as you live about 45 mins from me. E -Mail came back ring me 8760900
Modified by Mirage at 9:08 PM 4/9/2005

I am not dead sure how to work this website, I replied earlier but do not see my reply, so my apologies if I have duplicated .1.We sleeve with special sleeves, this is cheaper than stroking and helps keep the torque up.Using this system The Nissans are making more power and are much cheaper to build than Chevs & Fords2.We have heaps of VH45 but they do not breath as well as the 41 and the 41 is really an evolution of the 45, they have tidied up a number of things and nothing is really interchangible.Our Methanol engine 830 hp is a 41 block and handles the power no problem, so stregth not a problem with these engines3.I have a friend who is transplanting a VH41 into a Sylvia now 4wd. The VH41 came out in a 4 wd at some point and some have sumps with diff mountings and a whole through the sump for a trans axle. I have been following his progress, and whilst things are tight it is coming together neatly. The back of the engine is about an inch from the firewall and he seems to have fabricated a neat header exhaust system. You are quite right we are right hand drive down here which has its own set of challenges when modifying.4. No, all our components where possible are standard or modified in N.Z.The Methanol engine runs Carrillo rods and Ross pistons. Crankshaft made here and cams I think Australian, everything else has been custom built here by N.Z engineers5,Have you got an exploded view of the VK45, I have one of the VH45 only, and perhaps you could advise me of the website of Impul.6.The VH41's (sleeved 240 cu in) are dynoed to 9500 and are raced at these revs ;and more!!!! for a season with total reliability. I would have to check with our engine builder to know exactly T.B.O. but from what I have seen I suspect the hrs will be quite high.As far as I know not one of these engines has let go apart from one which had its oil line assembled back to front (remote filter I think) and even it lasted 3 laps .There are also a number of Lexus engine running but they are not as strong in the blocks and can saw themselves in half longitudinally6. Our river racing is done on a variety of rivers occassionally with Canadian and U.S. representation (World Champs) and we see just about everything powering these boats. Most of the open class run N.A. big blocks (610+ cu in Alloy) or Turbo Fords and Chevs. Our rivers are mostly "braided" and quite shallow you will often be in 6 inches of water.

Mirage wrote: 2.We have heaps of VH45 but they do not breath as well as the 41 and the 41 is really an evolution of the 45, they have tidied up a number of things and nothing is really interchangible.Our Methanol engine 830 hp is a 41 block and handles the power no problem, so stregth not a problem with these engines

5.Have you got an exploded view of the VK45, I have one of the VH45 only, and perhaps you could advise me of the website of Impul.

6.The VH41's (sleeved 240 cu in) are dynoed to 9500 and are raced at these revs ;and more!!!! for a season with total reliability. I would have to check with our engine builder to know exactly T.B.O. but from what I have seen I suspect the hrs will be quite high.As far as I know not one of these engines has let go apart from one which had its oil line assembled back to front (remote filter I think) and even it lasted 3 laps .

There are also a number of Lexus engine running but they are not as strong in the blocks and can saw themselves in half longitudinally

6. Our river racing is done on a variety of rivers occassionally with Canadian and U.S. representation (World Champs) and we see just about everything powering these boats. Most of the open class run N.A. big blocks (610+ cu in Alloy) or Turbo Fords and Chevs. Our rivers are mostly "braided" and quite shallow you will often be in 6 inches of water.

2. I wonder why that is? The valves are the same size, and in the implementation in the US, the 45 revs higher in spite of its longer stroke. Here, the 41 is regarded as less robust than the 45 because of the lack of the lower crankshaft girdle. I may be wrong, but I think with the idler chain driven exhaust cams, the intake camshaft timing is not variable like th 45. So please elaborate when you can.

5. I think there is one in the FSM. I'll email it if so. http://www.impul.co.jp/

6. Are they sleeved for strength, or an arbitrary racing rule limiting engine size? Are they sleeved with cast iron liners shrink in?

At 6" of draft, we'd be in swamp boats with pusher props. Must get hairy.


Modified by maxnix at 7:19 AM 4/12/2005

Hihave just finished talking to our engine builder to clarify a few points.The VH41 has both a girdle in the bottom end(same as 45) and has variable timed cams (inlets) the timing chain setup is better, the heads breath better. the engine is probably lighter. One of the few swaps is to put the VH45 crank into the VH41 block. The major advantage of the VH41 is that the heads flow extremely well stock.(Way better than the siamesed VH45). He has just started work on a late model Vh41 and noted there are some port differences(improvement) as he does more work on it we will see exactly what the differences are.

I note you say that the VK engines are open deck. Can you explain what you mean here as I am familiar with engines having quench areas or no quench areas but as these engines are pent heads I do not understand what the differnces are.

The Vh41 (240 cu in) are sleeved back to meet class requirements, the sleeves are of a high tech steel material. To run 9-10000 rpm rods cams and valves are changed or modified. To date no engines have come back for a rebuild due to wear, or mechanical failure, it has all been from running out of water or oil.Best guess is that these engines would do 2 or 3 seasons if the racers kept them oiled and watered. Cost of building these engines here is about 25% of building a Chev or a Ford.It crosses my mind if there was interest we could supply parts or engines to anyone interested.(Emmission requirements??????)Our river racing can get very spectacular particularly if you hit a rock doing 80 M.P.H.+ as often happens, however in the shallow water going agroung is the biggest threat.

P.S the stock VH41 with cams will be on the dyno next week so will be interested to see the power and torque figures

Mirage... you should post in Infiniti General.

This forum is not well traveled and you will have a larger audiance there.

Thanks for the advice, will do.

I want some pics of this boat. We are all anxious to see the Nissan motor in your boats. I'm sure someone will host video as well if you can get some footage of your boats in action.

i am about to put a slightly worked VH41 into a 4 door R32 Skyline and need some information. First are there any bolt up gearboxes/bellhousings for these? I am wanting to convert my motor from Auto to manual. Custom intakes? Any ideas? also what computer would be best (Also Cost effective)

Z32 300ZX manual box is meant to have a few common bolt holes ... but requires an adapter plate

My microtech does the job on my VH45 turbo ... the R33 VH45 with pro charger runs a microtech as well.

I chose sequential injection and batch fired / dual post coils ... but you can use semi seq injectors and use standard coil on plug setup if you like

$1050 AUD ... $1345 RRP (this opens up many MANY mods as i'm sure you know)

nothing beats microtech for the money

Hi, i know i'm chiming in real late here, but i've been looking around for q45 performance parts and had heard about vh45 and 41 motors being used in speedboats down under. i plan on doing a vh45 swap into my z32 300zx but i'm having a terrible time finding parts for the motor in the states, any pointers? i would love to do a full NA build and possibly stroke it
Modified by riu at 2:48 AM 6/6/2006

what parts in particular?

because any genuine parts can be sourced from an infiniti parts dealer.

http://www.infinitipartsusa.com is a good resource

primarily performance parts. safe tuning routes for the motor, what will work and what won't etc.

this is why we need the VH engine section

what performance parts in particular??

well anything really, i want to see what i can do with the motor before i start the build. i know what its capable of, but i don't know how i would get there yet, what i would use to get there, where to find what i'll need to get there. i'm just trying to learn everything i can about the motor first before i take action

what i would like to do is a full NA build with ITB, manual tranny conversion, swap into my Z32. looking to produce somewhere between 450-600 rwhp maybe more, retain daily driveability, but most likely will just be a weekend car. hoping it lasts me a minimum of 100k miles


Modified by riu at 3:08 AM 6/6/2006

riu wrote:well anything really, i want to see what i can do with the motor before i start the build. i know what its capable of, but i don't know how i would get there yet, what i would use to get there, where to find what i'll need to get there. i'm just trying to learn everything i can about the motor first before i take action

what i would like to do is a full NA build with ITB, manual tranny conversion, swap into my Z32. looking to produce somewhere between 450-600 rwhp maybe more, retain daily driveability, but most likely will just be a weekend car. hoping it lasts me a minimum of 100k miles

Modified by riu at 3:08 AM 6/6/2006

Sounds exactly like what I'm doing, but 100k is not going to happen on an engine producing that sort of specific bhp. Will be putting some updates as mine goes along so will have info by then.I've had bespoke pistons and rods made but there's no reason I can't get more. They're not cheap though!

John Dixon wrote:Sounds exactly like what I'm doing, but 100k is not going to happen on an engine producing that sort of specific bhp. Will be putting some updates as mine goes along so will have info by then.I've had bespoke pistons and rods made but there's no reason I can't get more. They're not cheap though!

yeah, i've been reading your threads and posts, i'm glad someone is sticking with NA. i'm probably going to use your build as a guideline for when i start on mine, right now i'm trying to figure out what my best options are. I was considering the escort cast hi comp pistons, whats your opinion on those vs. your bespoke? i'm also hearing about a stroker kit, however i'm having a hard time finding it, everywhere i look, i end up being led back to the VK45 stroker for the F50(?) new Q45

Escort pistons are probably OK, but needed bespoke for mine due to the overbore. Also mine are slipper design and flat top.The stroker kit was made by impul and was $$$$ as far as I remember, you'd be cheaper having a new crank made or offset grinding yours to be honest.

Wow, i think i must be the long dead thread revival king lately,
But would love to do this to my spare vh45!
It would definitely give the needed torque to get the heavy Q going from a stop a bit better.
Did you guys stop at a 98mm bore because of block limits or piston issues?
Here in the states a 101.4mm (4") piston is very readily available.
Are people still messing with these engines?
I know LS is a better route for big cubes and if it were a different car i would go that way, but the VH is really what makes the Q so special. The rest of the car, while very nice and built very well, is not super noteworthy, other than how well it has held up to time's ravages. (Mine is still daily driven!)

Hey man am trying to carb convert a vk45 can you message me in reguards to how you run your spark timing

Paulgvk wrote: ↑

Mon Oct 18, 2021 4:56 pm

Hey man am trying to carb convert a vk45 can you message me in reguards to how you run your spark timing

Just a friendly heads up. New members with less than 10 posts cannot send/receive a PM.