VH45 vs. VK45 for a S30Z swap?

[PanzerAce]

So, first post on this forum, and I did search, but this is going to be a pretty unique project. So, here it goes:

Which engine platform (VH or VK) would you guys choose for either a NA or boosted engine build, and why?

My goals are: 400 or 600whp (400 if NA, 600 if boosted)Daily Driver reliability (assuming I do my part with the build)Stick shifta higher redline (say, 8k)

I *won't* be using any of the below, assuming it affects anyone's views:Manifolds (ITBs + custom exhaust for me)Electronics (going with a Standalone EMS)RodsPistonsCams

I'm not opposed to boring/sleeving the block for increased displacement, and I'd rather do that than crank the boost higher for a given whp. I'm also not opposed to using a VH41 crank (assuming that's possible) if that would help me meet my goals.

Thanks for any help you guys can give me. I guess I should probably post a picture now:



1973 240Z with a three liter L series, but I'm looking for a *little* more power and driveability

[redhat-z]

Just my $.02, doing a VH swap is way more involved than most people think. In your case, I would just get a P90 head with mechanical lifters, single turbo, Megasquirt and be done with it. You should still be able to get 400 - 475 out of that. Every VH swap is ultra stupid custom, sucks up all free time and money, and ends up being worth it if it works. Then you can say you have a Nissan V8 in your car that makes around 310 hp bone stock with high miles. I just would not suggest it if you can get the same power out of your current engine. That's like having an R32 Skyline with an RB26DETT and swapping it for a VQ35DET. Why, why, why?

[Mettler]

Between the VH and the VK, I choose the VH. Going VK would serve no other purpose than to have a later model engine... the VH is still stronger.

[PanzerAce]

Just my $.02, doing a VH swap is way more involved than most people think. In your case, I would just get a P90 head with mechanical lifters, single turbo, Megasquirt and be done with it. You should still be able to get 400 - 475 out of that. Every VH swap is ultra stupid custom, sucks up all free time and money, and ends up being worth it if it works. Then you can say you have a Nissan V8 in your car that makes around 310 hp bone stock with high miles. I just would not suggest it if you can get the same power out of your current engine. That's like having an R32 Skyline with an RB26DETT and swapping it for a VQ35DET. Why, why, why?

By that logic I should just go out and drop a SBC 350 into it. I want a non-US V8 for the same reason that I drive a Z instead of a 510, 951, or RX-7; why I drive something with a stick instead of an auto; why I DRIVE rather than walk, and why I intentionally got a car with no power anything, no AC, and a bad heater even though I DD it in weather that ranges from below freezing to 120+. Because I *want* to. I know that a VH is considerably more work than most other engine swaps. I know that I could make 400whp with my current block (swap the mikunis for ITBs, 2mm HG, P90 head, turbo, turbo exhaust, plenum, FMIC, piping, and a in tank fuel pump would be all I need basically). I wasn't asking "How can I make this much power period", I was asking "Of these two V8 platforms, which would you prefer as a starting point".

*deep breath*

Some other observations:1) I can't meet either of my power goals with an L series and still have it remotely drivable on the street. 600whp is *possible*, but on the 91 octane that I have to deal with it wouldn't be enjoyable.2) 20yr old engine with 310hp stock vs. 40yr old engine with 140hp...I'll take newer and double the power.3) Last I heard, people were swapping RBs out in favor of VQ and even VG engines for the greater displacement.

*another deep breath*.

Sorry man, but posts like that p*ss me off. If I had asked what the easiest way to make that power was, then that post would have been awesome, but that wasn't what I asked...

If you've got an opinion on VH vs. VK, I'd love to hear it though

Quote »Between the VH and the VK, I choose the VH. Going VK would serve no other purpose than to have a later model engine... the VH is still stronger.[/quote]Is the VH really stronger? I know that car companies make some stupid decisions pretty often, but did they really make a newer block...weaker?

[Bart]

I be

By that logic I should just go out and drop a SBC 350 into it. I want a non-US V8 for the same reason that I drive a Z instead of a 510, 951, or RX-7; why I drive something with a stick instead of an auto; why I DRIVE rather than walk, and why I intentionally got a car with no power anything, no AC, and a bad heater even though I DD it in weather that ranges from below freezing to 120+. Because I *want* to. I know that a VH is considerably more work than most other engine swaps. I know that I could make 400whp with my current block (swap the mikunis for ITBs, 2mm HG, P90 head, turbo, turbo exhaust, plenum, FMIC, piping, and a in tank fuel pump would be all I need basically). I wasn't asking "How can I make this much power period", I was asking "Of these two V8 platforms, which would you prefer as a starting point".

*deep breath*

Some other observations:1) I can't meet either of my power goals with an L series and still have it remotely drivable on the street. 600whp is *possible*, but on the 91 octane that I have to deal with it wouldn't be enjoyable.2) 20yr old engine with 310hp stock vs. 40yr old engine with 140hp...I'll take newer and double the power.3) Last I heard, people were swapping RBs out in favor of VQ and even VG engines for the greater displacement.

*another deep breath*.

Sorry man, but posts like that p*ss me off. If I had asked what the easiest way to make that power was, then that post would have been awesome, but that wasn't what I asked...

If you've got an opinion on VH vs. VK, I'd love to hear it though

Is the VH really stronger? I know that car companies make some stupid decisions pretty often, but did they really make a newer block...weaker?

I believe the VK is a little lighter, thinner casting block which makes it a little weaker? I read that some where, but the Nizpro in Victoria Australia are making BIG HP out of them so they cant be too badIf you ask me i would go VH as they seem to be stronger, and preferably go twin turbo, that would be SICK in your Z

[Bart]

I have also read stroking the crank (or VH45 crank) and boring can get you close to 6 liters.

http://www.kinsler.com/manifol...n.htmh ... im...a%3DN

http://images.google.com.au/im...a%3DN

[redhat-z]

Hey man, I just saw this,

My goals are: 400 or 600whp (400 if NA, 600 if boosted)Daily Driver reliability (assuming I do my part with the build)Stick shifta higher redline (say, 8k)

and assumed you thought you needed a VH/VK to make that kind of power. No need to get hostile.

[gs14racer]

All i can add to this is assuming your doing the work yourself its gonna cost a lot more than you think it is.

and of course the fact that there is virtually zero aftermarket support for this engine.

[tmorgan4]

I have also read stroking the crank (or VH45 crank) and boring can get you close to 6 liters.

http://www.kinsler.com/manifol...n.htmh ... im...a%3DN

http://images.google.com.au/im...a%3DN

Why have I never seen that first manifold you linked to? Anyone ever looked into it?

[DJ Raijin]

I have also read stroking the crank (or VH45 crank) and boring can get you close to 6 liters.

http://www.kinsler.com/manifol...n.htmh ... im...a%3DN

http://images.google.com.au/im...a%3DN

ITBs for a VH45??? Do my eyes deceive me? *sigh* too bad they'd never fit under a stock Z32 hood.

[gs14racer]

ITBs for a VH45??? Do my eyes deceive me? *sigh* too bad they'd never fit under a stock Z32 hood.

Thats been around forever, i called and spoke to kinsler like 1.5 years ago in reference to that set.. They where a one off for a guy in australia who had one of the indy vh45 motors, point in case tthey had already recieved 20 plus calls and interest and determined that they would not fit the regular us spec or jdm vh45 due to the fact that the bolt patterns where different.

[PanzerAce]

All i can add to this is assuming your doing the work yourself its gonna cost a lot more than you think it is.

and of course the fact that there is virtually zero aftermarket support for this engine.

Believe me, I'm well aware of how build costs and times go. There's a reason I'll be DDing something else while this is in the works.

Bart, I'm actually probably going to SC (centrifugals, probably Rotrex units) it if I can get it to fit that way (twins vs. singles are also up in the air).

[Mettler]

If you've got a bit of money to spend, then get a VH45 and trick up the internals and valvetrain.

There's a thread on here somewhere already comparing the VK internals to the VH, and they are significantly less meaty in the VK... and the block is lighter etc.

The VK has some small improvements... titanium valves etc, but the porting appears to be no better.

So really, it becomes an easy choice when you consider that in standard form, the VH is stronger and cheaper with the same performance potential.

[PanzerAce]

If you've got a bit of money to spend, then get a VH45 and trick up the internals and valvetrain.

There's a thread on here somewhere already comparing the VK internals to the VH, and they are significantly less meaty in the VK... and the block is lighter etc.

The VK has some small improvements... titanium valves etc, but the porting appears to be no better.

So really, it becomes an easy choice when you consider that in standard form, the VH is stronger and cheaper with the same performance potential.

Cool, I'll track that thread down. Normally I wouldn't be worried about stock internals, but add that to a lighter block and no real improvements anywhere, VK doesn't seem like a very good idea.

Now to go find a block. Any recomendations, or is it easiest to just grab an Infiniti for cheap and yank the block out of it?

[ken in az]

For a serious answer to the VK vs VH debate - nothing has been proven other than the rods on the VH are thicker. Most would perceive that it would be stronger, but with technology being what it is today, I'd assume that someone did a computer stress analysis and figured the extra thickness vs strength was negligible.

The VK is superior if you are looking for high revs. titanium valves on both intake and exhaust. Solid lifter design so the sky is the limit. lighter rotating assembly - yup thinner rods are lighter making the VK a better high rpm candidate.

Personally I think the difference between the two engines will only become apparent when getting up into the 700-800hp range when the limits of the two will just begin to show up.

If you are looking for cheap - then VH is the clear winner, but the VK is more advanced and no one, and I mean no one, had done one up yet except for some pro race/drift teams. There is a guy building a buggy with a 5.6 VK that looks sick....but the 5.6 engine has heads and cams suited for low rpm stock power. the 4.5 VK can rev to 7K stock and 7500rpm is a walk in the park.

Either way you go you will have to use a VH ecu from the early 90's as the VK series ECU operates on a CAN network which requires a series of other on board computers to operate.

Anyway you cut it, you won't loose with either engine, but NA I think the VK45 would be the trickest option. If you are boosting then I'd say flip a coin or check your bank account and decide accordingly.

[ken in az]

Oh, and I forgot to add that I am pretty sure that the Frontier 6sp trans will bolt up to a VK series engine so the use of an adapterplate might not be necessary.

Can someone confirm?

[jdm_master_X]

Cool, I'll track that thread down. Normally I wouldn't be worried about stock internals, but add that to a lighter block and no real improvements anywhere, VK doesn't seem like a very good idea.

Now to go find a block. Any recomendations, or is it easiest to just grab an Infiniti for cheap and yank the block out of it?

if you're looking for a vh45, lots of pick and pulls up here have Q45s in abundance for you to get them out of for only $120-200 (varies on what you keep on the motor).

[Magnum]

N

Oh, and I forgot to add that I am pretty sure that the Frontier 6sp trans will bolt up to a VK series engine so the use of an adapterplate might not be necessary.

Can someone confirm?

No that is incorrect. There is a post in this section about this.

[marksport]

I think the VH might be a stronger motor for forced induction with stock internals as it has the reinforcement girdle under the main caps. For n/a the Vk would be better with the lighter valvetrain. I am in the process of doing a side by side comparison of these two motors. The VK is simpler and has less parts. The VH is a nightmare to remove the manifold and just as bad once the upper is off as you can see the big mess under the plenum. Pretty much every hose there was brittle and broke off.

[PanzerAce]

[bunch o' pics]

I think the VH might be a stronger motor for forced induction with stock internals as it has the reinforcement girdle under the main caps. For n/a the Vk would be better with the lighter valvetrain. I am in the process of doing a side by side comparison of these two motors. The VK is simpler and has less parts. The VH is a nightmare to remove the manifold and just as bad once the upper is off as you can see the big mess under the plenum. Pretty much every hose there was brittle and broke off.

I'd be interested in the info that you come up with. Your pictures also make me *so* damn glad that I'll be ditching all the smog stuff, computers, etc.

Are you going to be measuring wall thicknesses, etc? TBH, it's starting to sound like which engine I use is dependent on if I want to build a high strung NA motor or a FI motor.

One thing I'd really be interested in if you can manage it is a bunch of specs on the dimensions of the engines, especially the width down at the crank case (where it looks like the VH has an AC unit or something similar bolted onto it), since that is likely where I'll be attaching my SC unit(s), since higher I'd run into issues with the exhaust and then the wheel arches..

[marksport]

I'd be interested in the info that you come up with. Your pictures also make me *so* damn glad that I'll be ditching all the smog stuff, computers, etc.

Are you going to be measuring wall thicknesses, etc? TBH, it's starting to sound like which engine I use is dependent on if I want to build a high strung NA motor or a FI motor.

One thing I'd really be interested in if you can manage it is a bunch of specs on the dimensions of the engines, especially the width down at the crank case (where it looks like the VH has an AC unit or something similar bolted onto it), since that is likely where I'll be attaching my SC unit(s), since higher I'd run into issues with the exhaust and then the wheel arches..

I just finished removing the lower manifold, power steering pump and few other brackets and the oil pans. The girdle from the VH45 will fit the VK45 as long as you bring over the studs or get longer bolts. I'll have to find the wall thickness as it was in the SAE papers I got. I'll measure the crankcase width next chance I get.

[PanzerAce]

I just finished removing the lower manifold, power steering pump and few other brackets and the oil pans. The girdle from the VH45 will fit the VK45 as long as you bring over the studs or get longer bolts. I'll have to find the wall thickness as it was in the SAE papers I got. I'll measure the crankcase width next chance I get.

Cool, thanks man. Dimensions on the engine and engine bay might end up dictating NA vs. boosted for me on this build (though seeing a recent thread on HBZ about a 330whp 3.1 liter L series makes me not so worried about that)

[marksport]

VK45 measurements:







Measuring from the top of the engine



Measuring from the top including the oil filler.











This is the same area as the above, image needs to be rotated.



VH45 Dimensions



















Measurements are about 1/2" or so as I had to get the right angle with the camera. If you are looking to put a supercharger under the driver side bank,the VK45 might be the better solution as the A/C compressor normally goes there. The VH45 has the oil filter there.
Modified by marksport at 8:27 AM 2/26/2009

[PanzerAce]

Woot, thanks for all that. Just to confirm what I'm seeing though (and in case the pics get lost somehow):

VK45 appears to be:16" wide at the crank case/oil pan area, counting the filter (13" without?, and it looks like there is some assembly adding another 3", what is that thing anyways?)24" tall from the bottom of the pan to the top of the heads (+ 4" for the oil filler)28" or 29" wide at the widest point of the heads~29" longand maybe 12" from the bottom of the oil pan to where the heads/bores start to seriously add width

VH45 appears to be:24" tall (This I doubt because of this picture: http://i705.photobucket.com/al...5.jpg but atleast it's a starting number)29" wide at the headsheads/bores extend 10" outward from the crank case (so 9" at the crank case/oil pan, correct?)and 25" long.

Question about the VH though, in the picture I linked, what is the bulge on the side of the engine that the VK doesn't have? And I presume that attachment outside the engine is the AC compressor mount you mentioned?

Good idea with the SC mount idea. The only problem is that supposedly the largest SC that rotrex makes (which is who I plan on going with unless someone can give me a real reason not to) won't even support the whp figures I'm aiming for, and that even running two of them, I'd have to be running the C38 series. ('course, it'd be useful if any of the guys running VH/VKTT setups could let me know how much air they are actually flowing for a given whp, not just the amount of boost). What I was initially thinking was that I would run one SC on each side of the engine, most likely right next to the crank case, right by the frame rails themselves. Course, I'm going to have to go out to my car this weekend and figure out where the front of the engine is going to end up relative to the wheel wells and all that as well...

Also, re: filter placement, I'm going to be running a remote dual filter and cooler setup. I'm going to be putting enough money into this project that I don't want an oil problem killing it...

One (semi-random) measurement that I could use is the distances between the front of the engine and the first exhaust port, and the front of the engine till the motor mounts. Also from vertical distance from the exhaust ports to the bottom of the oil pan/crank case/engine mounts.

Thanks again for the measurements, though, since they allow me to get beyond the "Hey this would be fun" stage to the "Hmmm....would it even actually work" stage.

[John Dixon]

I've already done some of the stuff you discussed (ITB's, cams etc.) on a VH45 more details here if you want a look: http://www.300zx-club.com/foru...t=932Think you need to register to see the pics.Also, vids here:http://www.youtube.com/watch?v=ncxR7xNcSfI