180sx Posted April 11, 2011 Share Posted April 11, 2011 So, my VG33E has pretty much hit rock bottom and I'm going to need to rebuild it. Upon doing research for my Kia Rio turbo project (yes, that was not a typo. lol), I stummbled across this site. They have a full engine rebuild kit that comes with new pistons. They also offer these in oversized sizes! I have a set of Infiniti VH45 pistons sitting in my garage right now. Problem is I can't find a machine shop locally willing to fly cut the valve clearances (one shop said they would, but the price was rediculous!). So I found this site. It's an awesome deal, at less than $400 for the whole kit. This would be so much easier than getting different rods and cutting into pistons. But, I have one issue. They offer them in .020 and .040 over. I want the bigger one. Anyone know if we can bore our blocks .040 over? Seems like a lot to take off, and I'm concerned about water jackets and oil passages being thin. I'm going to check with the Z31 guys and see what they have to say. Just wanted to let you guys know. RPM rebuild kit Jose Link to comment Share on other sites More sharing options...
180sx Posted April 11, 2011 Author Share Posted April 11, 2011 I just found my answer! these would be good to go! Now, if .030 makes it a 3.4L, what does .040 make it? Hmm. here is what i found from Z31performance.com okay, the VG30 broke through at 3.78". broke through right below the deck. VG30 will be okay to run all the way up to 90mm bore. You might be able to get away with VH45 pistons if you checked to make sure your walls were okay. VG33 has THICK walls.. they measured out at about .300ish thickness on a stock bore block. You could bore a VG33 all the way up to 99mm if you wanted to and you'd still have 5/32" to 1/8" cylinder walls. That would make it a 3.8 liter!!! haha You don't have to drop $$ to get machine work done, basic stuff like crank grinding and boring/honing is cheap, but also, cheap can be relative. our shop charges 89$ to grind a crank, and 10$ per hole to bore and 5$ per hole to hone, 50$ to surface each deck... so you could get away with a totally machined block and ground crank for under 300 bucks. Most prices are similar to ours, except for the big name race guys who do machine work, and all you're paying for there is a name. honestly, if it was my engine.. I'd rather oil the pistons/walls by adding a little more rod bearing clearance with a little more rod side clearance than put squirters in. I hate squirters, they are nothing but a failure point IMO. lots of engines are running high hp w/o squirters, I don't think not having them is a restriction. I always block 'em off, I'd rather have pressure than oil on the bottom of my pistons. I built a 4g63 for a buddy last year with blocked off squirters, and he's running 25 psi on a T88 and hitting high 9's in the 1/4 with no problems. http://www.z31performance.com/forum/viewtopic.php?f=1&t=10615&hilit=Boring+VG33E Jose Link to comment Share on other sites More sharing options...
tekazgtr1984 Posted April 11, 2011 Share Posted April 11, 2011 Good find! Keep us posted on your progress. Link to comment Share on other sites More sharing options...
Kingman Posted April 11, 2011 Share Posted April 11, 2011 Someone on the boards made a 3.8L at one point in time and the block cracked. I've read that thread a few times, tons of good info. That's a private forum though so people that aren't members can't read threads. Link to comment Share on other sites More sharing options...
MY1PATH Posted April 11, 2011 Share Posted April 11, 2011 (edited) the thing about the Q45 pistons... For one you use the same rods you already have and second they raise your compression ratio. 8.9:1 is terribly low (stock) 10:1 will yield more low end torque and better MPG. You can still run regular unleaded with 10:1 Perhaps you can send your pistons out somewhere for valve cuts Edited April 12, 2011 by MY1PATH Link to comment Share on other sites More sharing options...
Kingman Posted April 11, 2011 Share Posted April 11, 2011 (edited) You use VG30DE/DETT rods to fit the VH45 wrist pin which also bolts right to the VG30/33 crank, or you can modify the VG33 rods. Best cheap VG34 build would be this: VG33 block bored, VG30DE/DETT rods, VH45 pistons, VG30 crank, VG33 heads with VG30 cams, 300ZX turbo AUTOMATIC oil pump. Also, don't post up a thread/question on Z31performance. You WILL be hounded, told to search, called an idiot, etc. Edited April 11, 2011 by Kingman Link to comment Share on other sites More sharing options...
180sx Posted April 11, 2011 Author Share Posted April 11, 2011 No, I won't post there unless I've searched for a few weeks. haha. I just have a few posts there, but all bringing back old threads I've found from searching. And like kingman said, unless you bore the piston side of the con rod, you'll need to use the VG30DE(TT) rods. Those I have not had luck finding for a reasonable price. So my build will be: VG33 block bored .040 over (making it I believe a VG35...Ooh! Must check the numbers though) VG33 heads (maybe port and polished if i can find a shop to do it for under $600) VG33 crank (no point in changing this and my accessories, and this crank can hold a recorded over 600HP, so my N/A will be fine) VG30E cams from a WD And I must look into this oil pump from a 300ZX turbo auto. I may have to change my crank if I want to use this. Now, to save up! Jose Link to comment Share on other sites More sharing options...
Kingman Posted April 11, 2011 Share Posted April 11, 2011 The only reason why I mention the Z31T automatic oil pump is because it flows around 25-30% more oil, has stronger gears, and the later the year of the car the better the design. Manual turbo cars have the same oil pump as the NAs. The VG33 pump flows more than enough oil though. The VG30DE and DETT rods are the same. Same with the VG30E and ET rods. Link to comment Share on other sites More sharing options...
Kingman Posted April 12, 2011 Share Posted April 12, 2011 Wait a sec, you bore the VG33 block .60 over to get a VG34... not .30. Link to comment Share on other sites More sharing options...
180sx Posted April 12, 2011 Author Share Posted April 12, 2011 Wait, what? From reading Mike Kojimas article, the VH45 pistons are .30 over, netting a VG34. So wouldn't .40 over make it a VG35? Damn it...I need to crunch numbers. Jose Link to comment Share on other sites More sharing options...
Mr_Speed Posted June 14, 2011 Share Posted June 14, 2011 Hey guys. I'm considering the same modification. Where can you get a decent set of q45 pistons and rings from? Thanks Link to comment Share on other sites More sharing options...
silverton Posted June 14, 2011 Share Posted June 14, 2011 Factory cc on a vg33 is 3275. if you bore it .040" over, that's adding 1mm to the bore for a total of 92.5mm. which in turn makes the displacement 3375cc or 3.4L Figured along with some resurrection, there should also be some data added Link to comment Share on other sites More sharing options...
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