All MotorAll Motor Advanced Performance. Talk about Engine Swaps, Internal Engine work. Not your basic Y pipe and Intake Information.
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1990 Nissan 300ZX TT 5-spd - SOLD ;(
4th gen maxima coming in the spring!
Owner-Frankencar Performance www.frankencar.com shop@frankencar.com
Don't worry guys, even though i don't have my maxima i'll still be around. i'd miss you all too much
now that a 3.5 shortblock swap is a proven option, it makes sense that the vq33 stroker idea isn't holding much attention anymore, but i think it still merits investigation. Definitely doesn't merit bugging the crap out of the only people who actually have the werewithal to do it until they stop posting updates, but that has everything to do with being on a car forum (its universal) and nothing to do with vq 33.
I think the main questions that need to be answered about this parts combo are the ones that apply most to the people who are most likely to consider doing it, i.e. people with no tuning experience/knowledge or no intention of putting the time into tuning something. People who have the ability or willingness to do tuning work will skip this for the vq35 swap in its various forms, so this combo's potential appeal is mostly in the possibility of it being a wrench-turning mod and not a brain-wrenching one.
with that in mind, the questions that need to be answered most are these:
1. will the vq33 shortblock setup have adequate valve clearance when bolted to stock 3.0 heads and valvetrain using stock 3.0 cam timing? Since it's been mentioned that the compression ratio would be higher using the STOCK pistons, that by definition means that there would be less distance between the combustion chamber and the top of the piston, because if the piston, combusion chamber, and bore remain the same, the only way to change compression ratio is by changing the pistons TDC position in relation to the combustion chamber. Long story short, piston ends up closer to head, and for those that dont know, there are times when the valves are open and the piston is near TDC and if the piston was higher up in the bore, there's the possibility of contact. contact=bent valves=$$$$ and hard to fix. You COULD alter the cam timing to prevent contact but you're basically opening up a complicated can of worms and it goes beyond the scope of the people likely to consider this setup.
There is probably a mathematical way to check the clearance that some smarty-pants could do if he knew all the numbers, but the only real way to check this clearance is to put together a vq33 shortblock, bolt both 3.0 heads on (one with one each (int/Exh) of the stock valvesprings removed and replaced with a much softer one to allow you to move the valve by hand so you can check available clearance with a dial indicator), and put the stock vq30 cam timing setup on the front, set to the stock timing marks, and rotate the engine through a full revolution. if it binds at any point you're automatically done, interference=no go, basically. if not, then the engine needs to rotated in small increments and the valve clearance checked at points throughout the valve's travel, because the clearance isn't necessarily smallest at the valve's max open point. Difficult to explain, but it needs to be checked throughout the valve's travel. I dont know what a good amount of clearance is, plenty of engine builders would know, but if it is too tiny than you risk a bunch of bad things: a weaker then the rest or weaker than stock valvespring could not retract the valve fast enough, a chain stretching through its normal wear could change cam timing enough to cause contact, even a failing tensioner that might usually only make noise could cause cam timing to change enough to bend valves if this clearance is too small.
If it passes that clearance test, however, thats one big hurdle out of the way.
2. The stock oil pan needs to be checked for clearance. I'm not super familiar with VQ's (dodge guy) but i think they use a girdle on the bottom of the block with the oil pan bolted to that, if thats the case oil pan clearance issue is extremely unlikely but it still needs to be checked.
3. Reference sensor compatibility needs to be checked. Again, not too familiar with the VQ setup, but need to find out that even if it uses the same type of triggering system, if the slots/holes whatever are in the same position relative to the crank throws compared to the vq30 crank. since there are already running 3.5 swaps using 4th gen electronics, you can assume it will work electronically with no or minor changes, but the thing is, if the 3.5 uses a different positioning of its triggers to achieve different base timing, it might not show up on a full 3.5 but COULD show up with the vq33 due to higher compression.
If all the physical stuff checks out, then all that remains is to bolt it into a 4th gen and see how it runs on stock electronics.
The higher compression ideally should be accompanied by changes to fuel and timing but basically, it it runs decent on stock fuel/timing (i.e. no misfires or detonation on premium) then it will likely run stronger than a comparable vq30 , ideally tuned or not.
If it DOES run well enough to be considered daily driveable/reliable with no tuning, then all we need to know past that is if the power gains justify the cost.
If you look on car-part, the cheapest used motors often have caveats like FIRE ON TOP/ MISSING VALVE COVER / NO MANIFOLDS/ NO CAMS/ ONE HEAD GONE etc etc etc, point being you only need an intact shortblock for this mod, and if the cheapest full engines are about 500 bucks, you can assume damaged/ partially disassembled/ parts missing engines will be much cheaper but still have the parts you need.
as for costs involving the actual assembly, you'll basically need a full gasket set, i dont know what it costs for a vq but they range from 100-300 bucks for most engines. if you wanna reuse everything you can, the bare minimum is a set of headgaskets. another cost i'd consider mandatory if you're using used parts is the cost to rent/borrow a micrometer to check the crank and rod journals. Plastigauge for the used bearing clearances will be cheap, and most 3.5s have less wear on them than 4th gen motors at this point anyway so... You'll also need to rent/borrow a ring compressor to put the pistons back in, and maybe some assembly lube if you like that stuff.
its probly BORDERLINE POSSIBLE for a person who can do it themself to pull it off for around 500 bucks if they get good deals, but id say its likely to be a couple hundred bucks more.
As for labor, IMO you'd be better off bribing someone who knows their crap to help you do it yourselves than pay a shop. this is just my opinion, but if you dont want to be there every step of the way and try to learn as much as possible in the process, you shouldn't be trying to pull off a cheap motor swap/stroker build. IF it runs ok without tuning, then all you're really doing for this mod is turning wrenches, and the only knowhow you need is the knowhow to not break stuff. (admittedly, that's like the first 3 years of the car guy learning curve but if you have an experienced friend to help you you'll be ok).
So, all it takes is one person who has all the parts available and the knowhow to do to valve clearance check to do the first couple steps, and a willing guinea pig to check the last.
I'll do that experienced friend thing if anyone near SA,TX wants to try it.
Otherwise, hope my contribution as a curious stranger to the maxima world is appreciated :P
PS Check out my cardomain (ID Vigo327), you'll notice im very experienced at mixing and matching stock parts :P
if's there's a thread that answers those questions then great, i dont know where it is and won't go looking unless someone wants me to swap their car, i just found the link on ceasar's chariot link page and thought it was interesting. sometimes you have to lay things out in a very specific straightforward, systematic way on forums or people will hijack, spew useless crap, or otherwise not move the ball forward at all, just waste everyone's time being a half-*** car guy that only wants to fill up their free time cruising the intarweb, so i'm not writing huge-*** posts to come off smart, just trying to bump an interesting thread in a way that'll hopefully get some actual answers.
with that in mind, the questions that need to be answered most are these:
1. will the vq33 shortblock setup have adequate valve clearance when bolted to stock 3.0 heads and valvetrain using stock 3.0 cam timing? Since it's been mentioned that the compression ratio would be higher using the STOCK pistons, that by definition means that there would be less distance between the combustion chamber and the top of the piston, because if the piston, combusion chamber, and bore remain the same, the only way to change compression ratio is by changing the pistons TDC position in relation to the combustion chamber. Long story short, piston ends up closer to head, and for those that dont know, there are times when the valves are open and the piston is near TDC and if the piston was higher up in the bore, there's the possibility of contact. contact=bent valves=$$$$ and hard to fix.
Sorry to say it.. but you're way off.
Top put it simply...
Your volume of the chamber at TDC hasn't changed (providing deck height hasn't changed)
What has changed to increase the compression is the volume in a stroke based on same bore size and now longer stoke.
That larger volume is now squeezed into the SAME sized gap, hence more compression.
Piston to valve and quench etc HASN'T changed at all, infact the piston is now traveling further during a cycle, which in turn more distance over same time = faster, so chances have LESSENED for any contact if any existed on orginal engine.
Sorry to say it.. but you're way off.
Top put it simply...
Your volume of the chamber at TDC hasn't changed (providing deck height hasn't changed)
What has changed to increase the compression is the volume in a stroke based on same bore size and now longer stoke.
That larger volume is now squeezed into the SAME sized gap, hence more compression.
Piston to valve and quench etc HASN'T changed at all, infact the piston is now traveling further during a cycle, which in turn more distance over same time = faster, so chances have LESSENED for any contact if any existed on orginal engine.
The problem is that deck height has changed. Using the VQ35 rods and the VQ30 pistons results in the piston sticking up above the deck by .6 mm. This is less than the thickness of the head gasket (~ .9-1 mm), but enough of a change to cause some concern. Maybe not with valve clearance, since JWT markets cams that have a larger change in lift than .6 mm, and they work okay, but I would be concerned with piston to head contact due to rod strecth and thermal expansion at high rpm.
Well im sure some of yall saw the thread that IceY2k1 put up about this being possible. Since I had a spare engine (VQ30) and DaveB had a VQ35 sitting around, we basically test fit these parts. Thanks to both of these guys for helping out on this.
So basically I put in the VQ35 Crankshaft, VQ35 Rods and VQ30 Piston Head all going into the VQ30 block. This is a COMPLETE drop in kit. I mean even the main bearing caps, main bearing cap beam, and rod bearings were all from the VQ30 and it fit perfectly. Without a hitch. Now on a sidenote, not sure why it was said the VQ35 piston heads was dished/valve reliefs, but it doesnt. Its as flat as it gets. The VQ30 has an ever so slight dish to it.
So for you people who want more performance via NA application, this would be a HUGE benefit. It will stroke your engine to about a 3316cc and your Compression Ratio will go to 11:1 using stock parts. No need to buy custom pistons and rods.
Now on a sidenote, not sure why it was said the VQ35 piston heads was dished/valve reliefs, but it doesnt. Its as flat as it gets. The VQ30 has an ever so slight dish to it.
I didn't notice this at first, but this needs clarification. The first generation VQ35 engines (Pathfinder, e.g.) had flat pistons, but later VQ35's have slightly domed pistons with valve reliefs.
but the thing is a full vq35de swap might be more complicated in other vehicles.
I was gonna comment that this is old.... but then realized I dug up 4 year old threads myself.. so carry on....
__________________ WTB: 00-01 shifter linkage/shifter, front mud flaps a32 or a33, real speaker grill (a32), white spoiler led bar, i30 cleared rear brake lights,RPM switch, Side Skirts (paradox/ionic
arghh but does it work
yea yea i kno old *** **** thread but
the question was never answered
and in my case where i swapped a vq30 into my car
if i have a stock piston and a low compression piston side by side will the low compression piston be shorter. cause then will that solve the problem of the .6 over lap and then what would the compression be?
This can be done and has been. There is only one problem that needs to be resolved. The piston sticks out of the deck by 1 mm or so. The simplest solution is to have the connecting rod shaved. This means you have the cap shaved 1 mm then connected to the rod and then hone the rod and cap re shaped to fit the crank. If you are using stock pistons the compression ratio will increase to about 11 to 1.
Ferhan
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Don't believe your own bull****!
finally some friggin answers lol
thanks fellas
ok but then how about if i need to lower the compression down to like
i onno 9 or 8 something streetable with turbo?
finally some friggin answers lol
thanks fellas
ok but then how about if i need to lower the compression down to like
i onno 9 or 8 something streetable with turbo?
why go thru that when you can drop a 3.5 ?
if stroking it and going higher compression for N/A
why not save the trouble and boosted a 3.5
the engine is a stout motor with great torque ?
This is a pretty cool idea. I'm gettin nervous about my VQ30 now that its up around 190000 miles and I know its had a tough life.
Another option for the rebuild or swap debate.
is there anyway to get the pics reposted for us noobs to look at?
B
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02 Maxima SE 6spd w/HLSD
Mods - Stillen high flow intake, Fog light rewire, Ralco RZ STS kit and ES shifter bushings on the way
Future Mods - Brembo blanks, HPS pads, SS brake lines, ES suspension bushings, Eibach springs, Koni Yellows
Past cars
97 Maxima SE 5spd, FSTB, RSB, A4 Projectors, full audio overhaul -Totaled
96 Probe GT auto, CAI, full cat back, custom header - sold
94 Probe GT auto, full audio overhaul - Totaled
93 Altima 5spd, CAI, headers, full catback - totaled
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02 Maxima SE 6spd w/HLSD
Mods - Stillen high flow intake, Fog light rewire, Ralco RZ STS kit and ES shifter bushings on the way
Future Mods - Brembo blanks, HPS pads, SS brake lines, ES suspension bushings, Eibach springs, Koni Yellows
Past cars
97 Maxima SE 5spd, FSTB, RSB, A4 Projectors, full audio overhaul -Totaled
96 Probe GT auto, CAI, full cat back, custom header - sold
94 Probe GT auto, full audio overhaul - Totaled
93 Altima 5spd, CAI, headers, full catback - totaled
unless those VH45 pistons and/or rods were machined quite a bit.
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