No dissassemble Number 5!!

[IncorpoRatedX]

Hey guys, I recently sold "Snooki" my SWB 87 that I drove from LA earlier this year to my brother. Since my plan was to buy an SR originally I went back on the hunt and found a 'mechanics special' I named it Johnny 5 after the old short circuit movie and because this is my 5th montero.

the guy said that he had tried to do the timing belt and crashed the valves. he had the front engine covers off still when I showed up. The timing belt was on correct and he stated that he had since corrected the belt but it was too late.

I got it home and today I checked the compression with the timing belt on correct, he claimed he only cranked it over once and realized his mistake.

well I had 55PSI in every cylinder on the passenger side bank, so I started ripping the head off, suspecting that it had made the tiniest love tap...

pulled the head and it's completely fine, no signs of blown headgasket, cylinder heads hold fluid, so the valves are sealing up tight. Current suspect is the rings...

So now I'm pulling the engine out and stripping her down to bare block.

So, since I'm building it, lets talk power mods, i know the old turbo/supercharger song and dance, but lets talk all motor bolt ons, i'll strap an SAFC into it, put some exhaust on it, intake, ditch emissions and stick a wideband up it's backside.

anyone found higher compression pistons? i've got 3000GT twin turbo cams here, any knowledge of their profile against the 6G74 cams?

 

[SoCalMonty]

I can look up the cam specs when I have more time.

It depends where you want the power. If you want power in a useable RPM range, for the factory automatic trans in a 4600 lb truck, the most ideal thing would be to punch out the block and go with aftermarket pistons (JE, Ross, Wiseco, whatever). Stock compression ratio was 10.5:1 (!!!), so you probably shouldn't go higher unless you plan to run nothing but 93+ octane or E85.

It's going to cost a **** ton of cash to get a good return on an N/A build with that 3.5L seeing as how there's very little aftermarket. You can probably bore to about 3.8L which would make it a bit more torquey, but the pistons and the rebuild would likely run you in the $2k range. Honestly, I know you don't want to hear it, but a custom fitted M90 blower would cost less money and get you more horsepower and torque.

You can have a good cam shop measure out the stock specs and fab up some custom grinds to match the new displacement a little better; if you went oversized valves and ported heads, including the cost of cams, you could easily spend $2-$3k on the heads *alone*. I spent over $2k on a 12V VR6 head (one head) from a very good head shop with off the shelf aftermarket valves, springs and retainers. You'll have 2 heads and twice the valves. $$$$$$$$$$$$.

Assuming "value" is important (ie, everyone has a limit...if it cost $8,000 for 1hp, I doubt any of us would do it), and assuming you HAVE to tear down the block, I would punch out the bore to 3,8L and clean up the ports in the heads. I'd do maybe .010" off the decks of the heads and leave the stock cams. Couple that with a decent intake and exhaust (probably on the order of 2.5") and you should probably reach ~230 crank and around ~260 lb/ft to be on the conservative side. A custom header could be done for ~$250 (El Cheapo) to $~700 (nice custom high end job).

Though, if it were my money, a used M90 for $200 and some brackets fabbed up, along with maybe an RRFPR to keep costs down and a wideband, would get closer to ~255 crank hp and ~290 lb/ft, and cost less (again, conservative estimate). You'd have to keep boost around 6 lbs because of that high compression ratio unless you compensated with the custom pistons. May have to ditch A/C to make room for it, I don't know...but power per dollar ratio is going to suck hard on an N/A build on this motor.

Turbo is possible too, but that's slightly more high RPM power and I'm not sure that's the best match for a heavy truck with stock automatic shift points...you probably couldn't rev high enough to take advantage of it fully.


So...what kind of power do you want, and how many thousands of dollars do you want to spend on the engine? Are you planning to race it, tow with it, ? It's gonna be hard to make an average sized V6 in a heavy SUV "fast."

 

[viducce]

Would like to suggest this one....
Just the thought to have this in my Pajero is overwhelming....

Some lucky guy is doing it here...

http://www.pocsa.co.za/forum/viewtopic.php?t=3816&f=31

 

[IncorpoRatedX]

Sorry guys, I should have clarified, not looking to make it fast, wanting to give it more hauling power, midrange torque is where i'm looking. big money/big power isn't where I'm headed.

headers aren't available for our trucks but I found these and they might be worth buying and modifying to fit, i have access to laser cut exhaust flanges.

http://www.ebay.com/itm/Ford-Mustan...Parts_Accessories&hash=item2ec72f0b08&vxp=mtr

I'm not willing to sacrifice AC for any mods, i will be using this truck for daily use. I always run 93 octane in it as you should with a DOHC engine that has a knock sensor and ability to adjust timing advance on the fly...

I guess I could look into retrofitting a supercharger onto it.

 

[SoCalMonty]

Headers would be easy to have made from scratch, but good ones will cost you. It's a lot of labor, and the tighter the engine bay, the tougher it is to make them fit just right.

I think if you end up having to rebuild the engine from the ground up, you should bore it out as far as you can go, gasket match and clean up the ports while it's apart, with an exhaust system and intake. Headers and high flow cat if it's in the budget.

We don't get 93 octane here - but that's why there's a knock sensor. You can run 87 if you wanted to, and it won't hurt anything. It will just pull out ignition timing to compensate and you'll lose a little bit of power.

 

[off-roader]

One thing I'd add is if ur getting an SR smogged in Cali, its a good idea to run 91 octane to more easily pass..

As for running a supercharger, Frank on the 'wire has done it with a gen 1 v6 along with a full rebuild. He may have some pointers for you on that.

 

[eengler2]

A 3.8 6G75 crank fits, with a little block clearancing. Use 6g74 rods and aftermarket pistons with the modified pin height. Stock 93mm pistons get you 3.7l or you can bore for more. Be careful with too much bore. The 3.8s have different heads. With the 6g74s you get really close to the coolant ports of the heads when you go bigger.

Pampena Motorsports can hook you up with the pistons. They are usually 8:1 for turbo builds but they are custom anyway so I'm sure 10 or 11:1 wouldn't be a problem to order.

A lot of us do 6g74 swaps in 3000GTs. The 3N heads (from FWD 6g74s or 6G72s) are a little better than the Montero heads (3T I believe). Turbo heads would be even better.

**If you want more NA pulling power on pump gas, 6g75 crank stroker is your best option for anything appreciable.**

If you plan to turbo or supercharge, upgrade the rods. I just found out they don't take 500awtq in my 3000...oops 400tq is probably a safer limit. With pump gas you have to worry about the stock cast pistons if you have any detonation. I was running e85, so no issues with pistons at 450awhp/500awtq.

 

[IncorpoRatedX]

more info on your set up eengler2?

If i even consider the supercharge route, i'd be doing it on stock compression engine with a refresh, run 5-7psi, defintiely not looking for 450awhp, i dont even need that in my fun cars...

 

[eengler2]

My new to me Montero SR is stock but just did VSS, timing belt, waterpump, oil cooler lines, cam seals, etc.

My 92 3000GT VR4 I had a built 3.0 but spun a bearing in it before I got a chance to crank it up. (Long story with no definite conclusions). Swapped in a stock 6G74 from a JDM debonair with my turbo stuff...billet td05 turbos, AEM EMS, twin aeromotive 340 pumps, 1350cc injectors, E85.........Enough turbo and fuel for 800awhp.

Wanted to drive around with the stock 10:1 for a little while this summer at 4-500awhp before building the motor. The springs I had in the wastegates only allowed a min of 16psi. Backed off timing at peak tq big time but still made more tq than I wanted. 500 was too much. In hindsight, I should've just bought different springs for wastegates and would be cruising right now.

Now I probably need a new block (haven't pulled it yet), but will do the 3.7 stroker I mentioned and go for 750awhp like I built it for

 

[IncorpoRatedX]

some info i've found while browsing around;

early 3000GT twin turbo ECU's appear to have the same plugs as the SR ecu, would make sense, being that it has all the same sensors, the tune and rev limit should be the difference. so, injector resistor pack, low impedance 450cc injectors from a DSM, 3KGT VR4 fuel pressure regulator and it should be boost ready...

now to see if I can find a supercharger set up for cheap, or if I should just go with a single turbo. Not too certain how intercooler routing would work out considering i want to keep all my accessories

 

[eengler2]

If you are going low boost, skip the intercooler and go meth/water injection if necessary.

 

[IncorpoRatedX]

If you are going low boost, skip the intercooler and go meth/water injection if necessary.

that makes absolutely no sense in terms of daily driven longevity. The need to constantly fill up would defeat the purpose of the build. This needs to be a turn key, well executed build with readily available replacement parts. Something my girl could get behind the wheel of and not feel like she's going to destroy it if she pushes the skinny pedal.

 

[mapper]

Reading this because I find it interesting. What about a subaru style intercooler on top utilizing a hood scoop? Alternatively my VW Passat (B5 chassis, same as Audi A4) has the intercooler mounted in front of the wheel completely out of the way of central mounted front accessories. Compressed air routes from pass side mounted snail, through the front rad support to low end of if intercooler on driver's side, then out of the top to the intake. Not super-efficient for a BT but good for daily driving. Might be worth looking at how B5 S4 models were designed since they flow more air...I think it was two intercoolers in front of each front wheel.

I don't own a Monty so I have no clue if there is room but it would keep it accessible and out of the way of other accessories. Just some ideas that popped into my head so thought I'd share.

 

[off-roader]

Might be worth looking at how B5 S4 models were designed since they flow more air...I think it was two intercoolers in front of each front wheel.

Yes they have 2 intercoolers in front of each wheel for each of the turbo's. Also aftermarket options abound should you want to try to use them.

 

[IncorpoRatedX]

the thought occured to me, that instead of the grill, i could put the FMIC there, anodized black, stick a mitsu badge on it and call it done. mount the turbo on the passenger side, relocate the steering resevoir, have inlet and outlet of the fmic on the same side, im going to do measuring tonight. first things first; reading ecu pin outs and verifying a 3kgt vr4 ecu will work. if it does, i'll go from there.