Boring and Polishing

[Haitian_King]

Well, I've been up all night doing school work so I'm a bit punchy.

One thought that's been in my head for the last half hour is the possibility of boring and polishing a VH45DE for increased performance.

I've Googled it and gone through the forum, but I'm still in need of an answer.

This is coming from what I've heard some people do with racing engines and what not to increase HP.

Is such a thing possible for the VH? If one was to purchase a spare and have it rebored and rebuilt, what would that entail?

Sorry if this is a bother to anyone, I'm just curious.

[Q45tech]

You don't bore an aluminum block due to thinness of iron liner. Anytime you change bore you need new liners, pistons, different head gaskets and redesigned heads.

Most Japanese racers increase the stroke to save expenses just new pistons, rings, rods, crankshaft and bearings.

Either way to do the job correctly will cost $10,000 > $20,000.I seem to remember JUN offering a [$10k] kit to make a VH45 into a VH49 about 10 years ago but it is no longer on their website.

Dream on. Much cheap to use a new FX50 engine and transmission, harness ecu, etc.

[Haitian_King]

You don't bore an aluminum block due to thinness of iron liner. Anytime you change bore you need new liners, pistons, different head gaskets and redesigned heads.

Most Japanese racers increase the stroke to save expenses just new pistons, rings, rods, crankshaft and bearings.

Either way to do the job correctly will cost $10,000 > $20,000.I seem to remember JUN offering a [$10k] kit to make a VH45 into a VH49 about 10 years ago but it is no longer on their website.

Dream on. Much cheap to use a new FX50 engine and transmission, harness ecu, etc.

Thanks for the info. I had hoped it was something that could be worked on in my spare time if I ever decided to buy a spare engine and rebuild it.

At that price, trying to squeeze .4 of a liter out of the VH seems like a waste of time as I'm not trying to set lap records.

Thanks again!

[PanzerAce]

You *don't* need redesigned heads to overbore an engine. And I have to be honest, I really pity you if you're getting charged 10 grand to re-sleeve a block. Hell, getting a longer stroke crank probably would cost more than a good set of rods, good pistons, and the re-sleeve job.

[gs14racer]

Yea seriously, you can get a 5.0 liter block stock stroke with forged pistons and sleeves completely rebuilt for around 4500-5000.

John dixon is running a 5.0 with stock stroke as well, heads do not need redesign and you can just o ring the block and run a copper headgasket and IF you want unshroud it a bit to make up for the increased bore

The vh45 is not a jet engine, its a regular motor just like all the others, same rules apply to it as all other internal combustion engines for the last 100 years.

[Haitian_King]

Yea seriously, you can get a 5.0 liter block stock stroke with forged pistons and sleeves completely rebuilt for around 4500-5000.

John dixon is running a 5.0 with stock stroke as well, heads do not need redesign and you can just o ring the block and run a copper headgasket and IF you want unshroud it a bit to make up for the increased bore

The vh45 is not a jet engine, its a regular motor just like all the others, same rules apply to it as all other internal combustion engines for the last 100 years.

What I was hoping for was the dependability of the VH45 with just a bit more power. Nothing outrageous.

Who's John Dixon?

[nismos145]

5.0 vh startup vidhttp://forums.nicoclub.com/zerothread?id=382820

Build info and mischttp://forums.nicoclub.com/zer...Dixon

[DJ Raijin]

What I was hoping for was the dependability of the VH45 with just a bit more power. Nothing outrageous.

Who's John Dixon?

Your best bet would be get an exhaust and intake for a little bit of pep. That shouldn't ruin the reliability of a VH45 very much if any at all.

[Haitian_King]

5.0 vh startup vidhttp://forums.nicoclub.com/zerothread?id=382820

Build info and mischttp://forums.nicoclub.com/zer...Dixon

That was extremely helpful. Thank you!

[Orphan]

First off what do you want out of the engine, then decide on your price limit and just figure out the best way to meet your goals in your price limit or get as close as you can.

I spoke to a local machine shop and they quoted me $600ish to put in the sleeves if I supplied them, besides that all you'd need is 98mm pistons and if you have the dosh decent aftermarket rods. The standard rods x rayed and shot peened should be fine for 400-450hp and 8,000rpm with ARP bolts but its cheaper to spend $1000-1500 on top rods from the start rather than fix the damage later if they do give. I would tend to want to put some better rods in if your going to do any work with the crank etc out as its just easier to do it all at once.

I would agree with gs14racer's price. I'm not really sure on the cost of a custom head gasket but from what i've seen your looking at around $350. Does anyone know if you can have the standard gasket CNC'ed out to a 98mm bore? I have never delt with modifying or custom head gaskets.

[PanzerAce]

300-350ish sounds close to what I remember for custom HGs. Haitian, you might also consider going with O-rings depends on your goals, experience with tuning, etc.

[maxnix]

Your best bet would be get an exhaust and intake for a little bit of pep. That shouldn't ruin the reliability of a VH45 very much if any at all.

Custom intake will do nothing. Custom headers will do a little, see rsiwicki's posts.

[John Dixon]

That was extremely helpful. Thank you!

More detailed stuff here too:http://www.300zx-club.com/foru...t=932You'll need to sign up to see the pics.