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1972 510 Build VG30ET Swap

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My First Post!


I bought a 1972 Datsun 510 2 door, and with the car got a VG30ET and T5 manual transmission (Old 300ZX).  The 510 previously had a VG30ET, and the one that came with was from another car.  Had AC and Power Steering, so wasn't the one in the 510 when it blew.   The guy that sold it said the VG was likely good, but did not make any promises.  


Leak down test was good for all Cylinders, except for #3 90/25 psi, something terrible like 75% pressure loss (sounded like it was leaking from the bottom).  The other 5 cylinders were all great 90/85, ~ 5% leak.  


At this point I am thinking the VG is going to be costly to tear into.  From what I have seen on forums the VG30 is not an easy engine to rebuild, and if done professionally over $3,500.  At that point maybe I just go to a junk yard and try another VG or choose a different power plant.  


For what is worth... the car is currently set up for the VG


My question are.


1  Is there a common problem with VG30ET's having pressure loss in #3?.  

2.  Is going with the busted VG as a builder an affordable way to shoot for 200-250 hp?  If not, what is a better route?

2.  If the VG is NOT the route to go, what kind money could it bring toward a new engine?

3.  Anyone want to swap a VG/transmission with 5/6 good cylinders for.....?  I live near Denver.  







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If the air sound is the intake... clearance is too tight, bent or stuck valve or bad valve face and or seat. It the exhaust, same as the intake. If air sound is from the valve cover air is getting past the piston. This amount suggests a broken or holed piston, very likely on a turbo engine.


The VG30 is a monstrously strong and reliable work horse. A turbo will trash any engine.


A broken engine is worth it's weight in scrap.


What about a VG33ER. Supercharged and makes over 200 hp. Found in Xterra and Frontier  

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No swap is likely to be cheaper then sticking with the vg. Like Mike said there are other vg options you could try.


Vg33 blocks are cheap and plentiful from late 90s pathfinders. Instant 10% boost in displacement.


Vg34 builds can be very strong and efficient. Over bored vg block with q45 pistons.


All vg heads are identical as far as I've ever heard. No changes from turbo, supercharger, or natural aspiration, so head work can provide huge gains.

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The best way to answer question #2 is knowing what you want to do with the car. Show, Street bombing, Autocross, Track, Drag, all of the above?


The strongest argument for the VG is torque and gobs of it compared to a naturally aspirated SR or even a KA. With a turbo you can get more than 250hp out of these 4 cylinder platforms for less money than the VG. You will not get the low end torque that a VG will deliver though, and in a light 510, a little more torque can go a long way. My SR20det makes a very reliable 330hp at the crank (not going to say how much I spent  :unsure: ), but on an autocross track, it is murder trying to keep the engine wound up in boost range. I would imagine a well sorted VG with 250hp would give me serious trouble.


In terms of cornering, weight is a serious factor. The SR is the lightest, KA next, then the cast iron VG30 but not by much. Each increasing in torque along with weight. One advantage the VG has over the KA is it sits back further so better weight distribution. 


Getting a reliable 250hp out of a naturally aspirated stock bottom end VG is not unheard of. Aside from a modified intake plenum there is all the head work/cost cams and exhaust X2. Personally if I were investing that much in the top end, it would be foolish not to prop up the bottom end, and bingo... you're into it for serious bank. 


If you want an all of the above kind of swap while getting the best bang for the buck, it's hard to beat the KA. 

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I would never even consider handing someone $3500 to rebuild it.

Wrenches, genuine Nissan shop manuals are easy to find.

Figure on $300-$500 in parts, and at most $300 for possible machine work, and a little time on your part.

Buy an engine stand for $100 at most, and an engine hoist for $200 at most.

Maybe a few tools that you don't have.

Still cheaper than making several house payments of some mechanic, who won't care about your engine as much as you would.

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I agree with rebuilding your own engine, if it runs good in the first place. If it has problems, it may be a steep learning curve. Builders who have experience building a certain type of engine know what to look out for. Things that a garage builder can miss.


So if you're considering having a shop go through the engine, ask them if they have experience with the VG30 first. If they don't, go to someone else.

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All Great Thank you guys.


The 510 has a goal.... Look about as clean as $0 can get me and be able to roast tires.  No goals of a fully restored car, at least not for a while.  I want to get it on the road, and surprise people with the way it jumps away from a light!


There are clearly a lot of options on the 510 swap.  Someone told me that the cheapest engine swap is the one you have in your garage (that is getting funnier).  If the VG is worth nothing in its current state, I think I might pressure up cylinder 3, have a listen, and start chasing down the issue.  Worst case scenario, take it apart, and see.


Ill pressure it up tonight and post what I can track down.

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Ok, so checking a little closer revealed...


1 - 90/90  0% (Seems suspicious, but hey.  0%)

2 - 90/85  6%

3 - 90/25 72% (Heard leak in intake, relieved its not the lower end)

4 - 90/87 4%

5 - 95/93 3%

6 - 89/83 8%


So at this point.... Thinking that an intake leak is no where near as bad news as through the piston/rings.  I have heard these VG's can run forever, and take a decent amount of hp in their stock form.  So  chase down the leak, fix/replace only the bad valve.  New seals all around, and then see if it will fire up.  At that point I just "bolt it in" and call it a day.  I realize I am making this all sound very easy, but the idea is not to spend years working on this thing, and work with what I have.  


Im shooting for a budget beast, and I am willing to take the chances with stock internals, if all signs point to "good".  My goal is 200-250 hp on a pretty low budget.  Im $2200 into a 510, VG30ET, and T5.  Seems like I have everything else in boxes or bags, but thinking this thing is 95% here.  The hope has been so far, 200 hp and a  rolling registered/insured daily driver for less than $3,500.  


Can it be done, with a little luck and a major time commitment?  I have experience working on cars, never built one from an engine and shell, but have done engine work and tore apart suspensions, brakes, rear ends, drive train.  Good news is I meet more and more guys in the neighborhood that have build experience, and are quick to lend a tool or a hand.  So for hands on questions I have people near by to ask.  (BTW neighbor wants me to drop a 350 in it.  He was happy to see the VG fail, and suggested a V8.  That, is why I am on here)


At this point I think the VG in my garage is the way to go.  Sound nuts?

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Garage is where most of us build. Many don't even have that. Swapping a head or replacing a valve isnt bad at all. Take tons of pics, start a build thread, do a little research, and ask when research fails. We can get you to the finish.

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A few months ago I bought my first Datsun! 


I found a local seller in with a 1972 Datsun 510, the car interior had been stripped and previously had a VG30ET (firewall, and mount work done, as well as cutting body for intercooler plumbing).  The previous owner must have blown the original engine, removed it, and then bought a junkyard VG30ET and sold it with the car (uninstalled). 


What its got

Car had a roll cage (taken by seller)

R200 rear dif (unknown ratio or if it has LSD)

Short Hurst shifter

Good glass all around

280 strut swap

Coiler over and camber plates

3" Exhaust


Boxes of things you would expect with a complete car... dash, wires, nuts/bolts, 4x ECU's

T5 Manual transmission

Battery moved to trunk


I paid $2,200 for the gutted car engine/trans and parts, I have a TOTAL budget of $3,500.  Right now I have $1,300 left to work with.  All of which needs to go into putting the engine/transmission in, and getting the car moving. 


The goal:

0$ On cosmetics.

200-300 hp

Loud, quick, and massive burn outs


Shooting for a daily driver with a twist


Now for the bad.  I am new to forums, so I am taking over from my previous post in the "Technical > Engine" portion of the forum.   Sorry for being a newb. 


Did a leak down test, and failed. 


1 - 90/90  0% (Seems suspicious, but hey.  0%)

2 - 90/85  6%

3 - 90/25 72% (Intake valve)

4 - 90/87 4%

5 - 95/93 3%

6 - 89/83 8%


I have taken the heads off, and stripped the engine down to pistons, oil pan, and crank.  So, where do I go from here?


At this point.... Thinking that an intake leak is no where near as bad news as through the piston/rings.  I have heard these VG's can run forever, and take a decent amount of hp in their stock form.  I pulled the heads yesterday, and am going to pull the oil pan and look at the bottom half of the engine.  Here are my questions.


1.  Intake valve on #3 is bad, heads need to be gone through.  Thinking $200-$300, I need to call around.  For the HP goal, the stock head set up will be fine, right?

2.  Pistons/Crank.  If everything looks good do I need to take apart pistons/crank and have the cylinders and crank machined?  I know I "should" but if I can see the cross hatching on the cylinder walls, can I let it be?


Pic link in my signature.  More to be uploaded soon.



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Depending on what type of damage is present, you may be able to just change that valve for a new one and lap it in. If you get one head totally refreshed, do the other as well.


Leaving a solid bottom end completely alone is something i have done frequently for budget builds.


I think stock heads will be fine. Vg33er uses the exact same heads and that engine puts down 210hp and 245tq, so the heads themselves are capable of it.

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omg those pics... why does this shop (looks like where you picked it up from) LOOK sooooooooo familiar?

That's not Alex's shop in Boulder. But I know I've been 'here'. Is that down in Englewood?


BTW, nice starting point! Awesome! So jelly. :thumbup:

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Don't bother doing just 1 valve. You'll end up paying the same or only slightly more to do all the valves on that head. (as painful as it is for me to not tell you just to do both heads...)


I watch it happen all the time, you do a valve job, the rings go out next. You do a bottom end job and don't freshen up the heads, the valves go next. Happens *often*.


But, it's your car, your engine. Ratsun is as ratsun does...

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@uieluck.  Not far from Englewood in Arvada.  There is a guy in town that has a 510 shop, TJ.  He sold me the car and motor, and was super helpful.  Offered to help me with his experience or getting any parts I needed.  I think he goes out to Elkhart Lake as part of a crew for someone racing a 240 every year.  



And my hopes of not touching the bottom end are gone....


Last night I ended up taking the engine completely apart, right down to the block.  Looking through the cylinders I saw what looks like a fracture/deformity in a cylinder wall.  I could home hone it, but I am suspicious that I need to take the block and heads in to be gone through by professionals.  Likely bored out to see if this is just a surface mark, or if the cylinder is toast.  



Anyone seen this before?


Should I just home hone and see if it disappears?


Anyone have an idea what I should ball park to pay for heads and block work?  At this point I am still on a $1,300 budget, my hope is a rebuild kit and machine work will be about $1,000.   



Crank looked good, and both Rod and Crank bearings showed no excessive or unusual wear.  The cylinder is really my only concern, chem em out.  





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Merged your other post with this one.



Just looks like a rusty water mark. I don't see a ridge at the top of piston travel either. Scratch with fingernail. If it catches and holds it may be a problem. I don't think so.



If doing the head for that valve don't forget you have two heads. I would take it apart and see if you can just get away with some valve compound and lap it in. Do them all.

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