Will the vg30dett crank fit in the vq with modified rods? I want to destroke a vq motor and I dont want replies about how it's a waste and why not stroke it? I understand that each person has their opinion, I am simply wondering if you can do it?

 

try this thread https://my350z.com/forum/engine-and-...e-and-how.html

 

^lol, perfect reply!

 

 

Moved...

 

Can you destroke the VQ35? Yes.
Can you use a VG30DETT crank? No.

Will

 

12109-RRZ30
That is a part number out of the Nissan motorsports catalog for a vg30det crank that is listed in the vq35 section they have rods for it too. If youre still looking to try that it could be helpful

 

"hey can i ruin my engine? oh yah if you try and say im wrong dont bother because i dont care about the hundreds of professional builders for professional race leagues who say dont do it unless pushing 10k+ rpms because thats just opinion........" sorry my intrepretre kicked in. in for weak engine that gains nothing but sacrifices alot.

 

If you want to do this, get a billet crank made. Then custom everything else to make it work.

I know everyone hates on the idea, but I'm very much considering it for round two (far Down the road).
I'm very much into the idea of a de stroked, bored, sleeved 3.5 liter vq, able to rev to 10k with 288 cams and maybe an 8185. Or maybe just a billet block, billet crank, billet internals, 288 cams 8185 nitrous....

billet is just a different spelling of better.

 

thing is resmarted you dont need to, billet crank for sure but you can get 10k from stock stroke and a billet crank, the stroke isnt really insane. i wouldnt even look into destroking this engine unless your going for above that. this isnt like a f1 car pushing 18k rpms where the 10 ft lbs of torque they loose from shortening the crank a little actually boost hp 50+ from extra rpms, unless you going ABOVE 10k and looking for around 1600+ to the wheels your not going to need it.

 

Id just like to lower the rod stroke ratio so the engine would survive 10krpm of abuse regularly

 

 

VQ32 revving to 10k with a dry sump would be cool as hell.

 

honestly if i where going to go through the hassle of making that work i would go much bigger with custom cams to rev it to 12k( i mean with billet and a shitload of cost already might as well.), drysump, and at a minimum twin 7175 cea's or a single pro mod 91 cea, like i said for that cost that would be the smallest setup for that. other wise whats the point? at that rpm the chance of failure is just as great when pushed regularly so theres no reason to have all the additional cost if your not going to go bigger.

the bore to stroke ratio MIGHT improve wear some but its going to be the piston side skirts. also if its not a issue already its not going to do much. the important things like bearings and oil are still going to wear much quicker at that rpm regardless of stroke used. i wouldnt trust any engine at 10k or above regularly because the MAIN thing that is going to be a issue(oil system and bearings.) arnt going to change. destroking it is still going to need a refresh, or at least a tear down for inspection every 5k miles +- depending how you drive it. theres a reason nascar engines are rebuilt every race as are f1 engines and they dont come close to that mileage.

 

I understand what you're saying but id be trying to fix our rod stroke ratio. 1.7 ish isnt terrible but it puts more stress on our rods as apposed to a 2js 1.5. Lowering it would help things stay stronger.

Twin 7175's?! Thats nuts! Id love to see that

 

*shrug* like i said if looking to do it gotta make up for it somehow, especially since VE is going to take a hit with the shorter stroke due to lower piston speed. so def will have to go bigger then you plan, i would expect to factor in a extra 5% loss on top of what you think you will loose from displacement to account for the VE.

seems like your trying to fix something that isnt broken though as plenty of engines have similar/close to the same ratio with no issues revving that high.

i mean i get you want a engine to rev that high but your still going to break things and regularly tear down the motor all you will end up doing is going from replacing pistons never(unless you somehow do something crazy like melt a hole in one) to replacing them never +20k miles.

10k rpms + longevity dont even belong on the same page, because even if its just bearings your going to be replacing them alot

 

yeah the 4g63 has the same rod stroke ratio but the factor your missing here is the displacement.

See we have a lot of natural midrange torque which will hurt rods with this R/S ratio, which I believe is precisely why eagle rods tend to break sooner on our engines than 2j's with similar or sometimes greater power/torque.

By lowering piston speeds we can increase the rev limit more "safely". The piston speed on a vq35 at even 8krpm is IMMENSE. Don't forget, a lot of our VE comes from our heads. Our heads are really quite good. Hell even stage three race cams on 2j's don't have much more than our stock lift. But also when you rev out you'll regain that VE, just at a much higher rpm that is more suitable for a drag car etc not a street car.

I totally agree with saying 10krpm and reliable don't belong in the same sentence in the traditional sense. But, when I mean reliably I mean "hey I could take this thing out to 10k right now and it should live to tell the story" vs with our oem setup/piston speeds "yeah so how far do I want to throw the piston out of the block?"
I'd definitely want a billet block, because stuff is going to flex like a **** at those rpms!

 

gona try and contact some place like dart to have em make it if you do it or have someone local do it?


idk ls1 has only marginally worse and ive seen them go up to the 9k with much better torque without and issues, i think you might be miss thinking this though, a higher number rod stroke ratio is actually better for rpms and decreases piston sideloading since theres less movement at the piston. nascar for instance uses 1.91 and i know f1 cars aim for around the 2.5 area, and from the factory the 2jz has 1.65 r/s ratio although the 1jz has a slightly better 1.75.

i think the torque is the main area of failure on the eagle rods, because ive seen them fail regularly at under 500 hp on 383 motors and only marginally better on a 350, without even revving it that high(under 6500) in all honesty for a street car our rod/stroke ratio is actually pretty damn good better then even every honda 4 cylinder made minus the b16.

 

Currently not even going to contact anyone.
I want to see how this build runs and what problems I encounter... Then I'll probably work through a shop. I've brought it up with a couple of shops and some of the better ones have already kind of looked into it.
Realistically won't happen for another 5 years or so.

 

That is a part number out of the Nissan motorsports catalog for a vg30det crank that is listed in the vq35 section they have rods for it too