I have the 3.5 swap and just put in a new tranny, but now the car wont start! Car worked fine going in (excpet the old tranny died). My mechanic told me the Crank pos is not in the right spot. He said the hole was drilled out and the crank pos was not aligned properly making my car start for half a second and then backfiring until stall out. He also mentioned a ring being bent?

I know something is supposed to be modified to make the 3.5 sensors work with the 3.0 tranny, but I don't know the details.

If anyone can give a detailed description of what needs to happen to get this working please do. THey are working on it as we speak, but I can't give them the info needed as I was not the one who swapped the motor.
Thanks guys.

 

If the car worked fine going in then the crank position sensor has nothing to do with it. The starter is grounded directly to the engine block via the mating surfaces of said block and the transmission. Something that is commonly overlooked when installing a used tranny is making sure the tranny mating surface is completely clean. Since they probably wouldn't like to remove to tranny to do this, they should try installing a grounding wire directly from the starter to the frame. Again, i don't see how the CPS is an issue now as opposed to before it came into the shop.

 

It cranks fine, it even started but then stalled out after a few seconds. Its def the cps, can you give me the details on that? All i know is its not the same as the 3.0. Got details?

 

Which CPS and oil pan did you use?

 

I used all the 3.o stuff I beleive, but the oil pan i think was a 35. The cps must be from the 30 because I used all the 30 timing and harness.

 

It's possible to use the 3.5 CPS with 3.0 timing equipment but that's irrelevant at this point. The 3.5 oil pan requires modification if you're going to use the 3.0 CPS. Something about shaving some material away so the CPS can sit closer to the timing ring since apparently the 3.5 CPS is longer. But again, i don't see how installing a new transmission would affect this.

 

All i know is the mechanic told me that thee hole where the cps goes was drilled out, and the threads were stripped, therefore the cps had shifted somewhat, and the "ring" was bent. so I don't know whats going on now. I'm so disapointed in this stupid car. This tranny job is going to end up cost over 5000 all said and done.

 

If the timing ring is bent then you need a new one.

 

It's either one or the other. Either the CPS shifted or the ring is bent. Wtf?? If the car ran before then it should run now. The only way the timing ring is bent is if the fawked it up in the process of installing the tranny. Even if that's the case, they should replace it their damn selves. Wow, this is pissing me off and and it's not even my car. If only you lived closer....


Do you have any local orgers that could help? You're throwing money away there to tell you the truth...

 

what kinda of tranny job are you getting that will cost over $5k??? You can buy a used replacement for a quarter of that and new one for maybe $2K. Sounds like the mechanic is ripping you off. Go get a second opinion, why was the CPS hole drilled? was the thread stripped? shouldnt they have re tap the hole for a new bolt to keep CPS in place? For $5k sounds like they don't really know whats going...
A little history of the problem may help.

 

on a side note, what oil pan technically are we suppose to use for the 3.5 swap? The latest 3.5 writeup mention nothing about the oil pan but I've heard that 3.0 oil pan and 3.0 CPS would work best for the swap since theres no modifications but do we use the rear main seal of the 3.0 or 3.5 or are they the same? If we are using the 3.0 oil, can the 3.5 oil cooler be retain and would be modifications on that side to make it work? Some one who done the swap successfully shed so light on this please...

 

You can use the 3.5 oil pans with the 3.5 CPS with NO modification (just splice the wires into the harness)

You can use the 3.0 oil pans with 3.0 CPS with NO modification (but it's time consuming, and not worth it in the least.)

You can use the 3.5 oil pans with 3.0 CPS if you shave off 1/4 inch off the block where the sensor sits.

The oil cooler can be put on either oil pan.

 

If you do that then you have to plug the coolant fitting on the back of the block and use the 3.0 thermostat. Personally i'd rather keep the oil cooler, especially considering you plan on boosting this setup.
You must use the 3.5 RMS.
I've heard that the 3.5 oil cooler can be used on the 3.0 oil pump but i haven't heard of anyone pulling it off successfully.

3.5 CPS and 3.5 oil pan is the best option but most engines that people buy don't come with the 3.5 CPS and CPS subharness.

 

reason I ask is cause I'm comtemplating on pulling the upper oil pan off to change out the stock rod bolts for ARP's. I'm worried that the stocker wont handle reving up to 7k 7.2k consistently under boost and with the EU 2-step, I don't know if they can handle that either.

Now I have to go look and see if I have a 3.5 CPS harness that I can splice in. thanks for the help.

 

The 3.5 CPS has 3 wires too, just invert two of them, cant remember which. The ground is the same I think its the other two that need to be inverted. I never took off my 3.5 oil pan and never grinded anything on my first swap two years ago.

I dont want to short change the VQ35 but I would definately NOT rev a STOCK engine to 7000-7200 under boost. You would be asking for way too much trouble. Crawford doesnt recommend reving the stock engine above 6800 naturally aspirated. Ive read the load on the rods goes up like 45% from just 6000 to 7000. Thats huge.

If anything, I would do ARP rod bolts AND keep the 6550 Rev limiter. I would never go beyond stock rev limit on a stock, boosted engine. I would only do it on a VQ30 due to the incredibly oversquare design and thus incredibly low piston speeds.

IMO the extra 500 RPMs or so put so much more stress on the internals, its not worth it. I would concentrate on preventing detonation and head lift issues. I think the stock rods are strong enough but raising the rev limiter is not a good idea IMO. My .02.

Taking off the oil pan is a very quick, very easy job, just remember to change both crank seals (front and rear), they recommend doing that for every removal. At less than 200 bucks the ARP rod bolts are cheap for the peace of mind they bring.

 

+1. Most blown VQ35's with stock internals running up to ~450 WHP or so are due to poor tuning or excessive revs. Great advice here. Stick to the stock redline or below.

 

OK this thread went OT reeaaal quick...




To bring it back on topic, sounds like the mechanic shop is taking you for a ride man.

 

Thanks for the opinion. I'm just really toying with the that idea because the EU gives me that option but in reality I know what you mean, I already know that I'll be pushing the motor pretty hard with boost and to have it rev higher I don't think it would be a good combination. Like you say, I probably keep the rev limit around stock 6600ish.
I already have the J&S and EU and I'm still debating on whether to get ARP head studs and HKS HG. I already have some JWT HD valve springs which someone maybe buying from me, if that dont go thru, then those will be thrown in. With all of that I think I got the detonation and head lift issue taken care of. Its just a matter of the weather getting warmer so I can start working on it.

Does anyone know if the HKS HG works with stock internals? I know there are other options like the Cosworth Cometic and oem replacement but from everywhere that I read, the HKS is a better design.


LOL Sorry for the thread hijack. Back on topic.....

 

OT even more but there's no proof that head lift at moderate boost levels actually happens. It's likely cylinder bore distorsion that stronger clamping force helps prevent. But n/m that. The HKS head gasket is the best one out there, period. Another misconception is that the standard ARP head studs aren't reliable past 500 WHP. They likely are, but ARP recommends retorquing them after one heat cycle. Since that's not really practical with the VQ and nobody does it, the L19 studs (which allow for a high torque application) are the clear choice. Just wanted/needed to clarify.

We're getting ahead of ourselves though....an upgraded HG and head studs are useless of the rods and stock cylinder sleeves can't hang. And a completely stock VQ can handle upwards of 450 WHP reliably if the tune is on point and you keep the revs down.

 

That is where I read also that the HKS is by far more superior than any other HG's out there for the 3.5. The big question is from the specs, the HG is 97mm while the stocks pistons are 95.5mm would that be a problem?
L19 are better but double the price trying to do the swap on a budget

 

Head studs, ARP rod bolts, HKS headgasket and stock rev cut, you got one reliable 400whp motor that will last if tuned carefully.

Now how the hell did we get so off topic

 

Its all your fault

 

Yeah, I know.

 

hahaha, yeah I didn't really give you any details of what was going on.....

Heres the story, I had to buy a new tranny from Nissan cuz i tried to get a junkyard one but it was f'd. So I sent it back and lost money on shipping around 200. Then I had to rent a car (which I expected to only have for a week or less) but send the tranny back and waiting for a new one took a nother week. So at 160 per week and now its been 3 weeks. Pluss I got towed out of my own lot for expired temp. permit, that was another 150. Had to pay for labor on the tranny twice! because the old one was bad and the new one had to be put in (total 1100). Then when the new tranny was in the car would NOT start, so diagnosis was that the back valve cover was cracked and the plug tubes were flooded with oil! Yeah so that was another 50 for the valve cover, but they dont come with a seal so Ihad to wait for them to ship from New york TWICE, once for the Valve cover, and once for the seal (don't ask me why nissan doesn't carry it locally, or why they dont send the seal with the Valve cover). Then when the Valve cover was installed the thing still wouldn't start. ARG!!!! So we finally found out it was the stupid CPS went out of whack.

So all the labor charges at 80 an hour and I still dont know what the final bill is going to be!

Parts:
2250 -VLSD tranny (new from nissan)
160 -VLSD axel
480 -3 weeks rental car
150 - towing rental from my building (Permit expired)
165 - towing from track to building (nov 2006)
80 -towing from building to mechanic shop
560 - labor on f'd tranny before realizing it was f'd (hairline crack on driver side input, wouldn't hold oil)
200 - shipping lost to sketchy junk yard

Sub total - 4045
and I haven't recieved the bill for labor on the new tranny install, valve cover, cps fix.

My mechanic also found out that my header bolts are loose and need to be tightened but the rear bank is impossible to get to, so he will have to pull the exhaust to get to it, and something about the coolant drain was leaking because the bolt isn't the right one. Luckily he will do that on the side so i wont incur more shop labor rates. Along with that he needs to mill my rotors and fix the squeeking issue in my z calipers. Oh and the rad support is rusted through so that needs replacing too.

After this my car will be like brand new!


He's not taking me for a ride, but my car is. I've had him fix several things that other mechanics have done wrong over the past few years. He always puts it on the rack and shows me what they screwed up, and I always say "those stupid tards should have never touched my car", and then he says "I don't know why I keep working on this car when you take it to other people that mess it up for me to fix" Trust me, we both hate it, but mostly me cuz I have to pay for it (sometimes twice!).

 

I feel bad for you knowing what I did with 5000 instead.

 

Turbo? Oh and I just got my rental bill. $997! They slapped a 17.99 a day fee on because I'm not 25 years old. Laaaaaaame. I should have bought a car for that much.

 

Its not turbo but its still fun....

~Alex

 

Oooookay let's not turn this into one of those threads.....