Top Secret

So now that it has become apparent to me that this will be the engine that is going into my 240z, I have a few things to address, and a few questions:

I've decided that I won't be going with efi. I am, after all, a carburetor guy. I have been eyeing that pretty Victor Jr single plane intake for quite some time now. The only problem is, the Victor Jr. intake is good for up high. 3500-7000+ rpm. As we all know, these Vortec engines don't exactly like the higher rpm's stock. The valves start to walk at around 5500. (Or so I've read)

Question 1:

What mods do I need to fix this RPM problem? Just stronger springs? If so, which ones would you guys recommend and how high (rpm wise) would you all take this motor safely?

Now, I know there are those of who you simply say "Well, anytime you are increasing rpm's it's not 'safe". Which I agree with, but would would you think is a reasonable redline? 6000? 6500? I'd like to get an extra 1k rpm out of it.

The car it will be going into, the 1973 Datsun 240z, is going to be a road race car, and my new daily driver. (Taking place of the Chevelle, which is currently getting single digit gas mileage numbers.)

Question 2:

Although I've read that there are differences in the crank where the tranny attaches, what EXACTLY do I need to do to slap on a T-56 6 speed?


The 6 speed should give a nice little bump to gas mileage, and since it's a road course car, I'd argue that it is required...

Question 3:

Right now, I am thinking the engine needs a new set of bolts. Is there a kit I could purchase that has everything I need? Rod bolts, head bolts, etc etc?

So right now I have the stock intake, fuel rails, and 15 injectors I need to get rid of. I also need to purchase the stock coils at some point from someone. (Send me a pm if you've got some extras I can buy.) I'll be posting those in the for sale thread as soon as I get 50 posts...

Question 4:

Do you guys have any advice? Keeping in mind that this is, at it's heart, a budget build. I've been taking this project one step at a time since the beginning. It's finally starting to get to the "Wow, this might actually happen." phase.

I've done so much research... When I bought the motor all I knew about it was that it was a small block chevy. Now I know it's an LQ4 Vortec 6000 third gen small block at 364 cubic inches that is mated to a 4L60E transmission and produces somewhere around 300 horsepower/300 torque with 9.4 to 1 compression and 317 heads which run out of juice around 5400 rpm and can run about 8 pounds of boost stock (Safely). And there's so much more I have learned. I can safely say that even if this project ends up falling flat on its face, which I'm not willing to let happen, that it was worth it no matter what.

It's pretty amazing what 3 months of solid research can yield.

Thank you for your time. =)

And here are the cars.


My lovely 73 240z


And my lovely 72 Chevelle.

blown3qtr

Hey bro, welcome aboard. Sounds like a nice project. Should keep you busy for awhile. I have a buddy who is getting ready to put an lq9 in a '60 chevy p/u once we put his brother's 408 in. When I finish my 408 I hope to use my old block to build one for my '70 Lemans (wannabe GTO) but I plan on going fuel injected.

Anyway, a few things come to mind off the top of my head.
Are you going to rebuild the lq4?

1. Bolts: ARP, not sure about a whole set. a lot of sponsors carry them and are more than willing to help. Sometimes you will get a better price by calling them.
2. valvetrain: camshaft, LS7 lifters about $100, ls2 timing set, springs comp 918 or daul depending on lift, pushrods, titanium retainers & valves (depending on budget).
3. Not sure about a different crank for t56. I would suggest having the rotating assembly balanced. A stock lq4 can handle a 6000+ redline easy. Truck intakes tend to lean out #7 at higher rpm. Those mods should put you up into the higher 6k-7k rpm depending on cam and fueling. I'm not sure how a carb will change all that though.

Good luck and keep us updated.

Top Secret

Yeah, the LQ4 is gonna be rebuilt. The shortblock is currently sitting in the garage right now. But I have an extra set of rods and pistons that I am going to throw at it. I am going to call a couple machine shops around here and see how much it costs to dip, hone, and assemble the short block. I also have to buy new rings and bearings. Any idea how much that is gonna run me?

I forgot all about getting an LS2 timing chain. I've been told to ditch the stock pushrods also...

I've read that the Victor Jr. intake fixes the leaning out problem as it feeds all cylinders equally. (I've read.)

Cam wise, I'll be sticking with the stock cam until this thing is driving around, and then I plan on getting something ridiculous.

Slap up a picture of that 70 Lemans. Almost bought a 67 a year ago...

zippy

The stock springs are good enough for the stock cam. I would recomend more cam and either 918's or LS6 springs. As for rod bolts, I recomend the Katech rod bolt kit.

Top Secret

I've decided not to go with better bolts. Seeing how this is going to be a stock rotating assembly and a budget build, I just can't force myself to shell out a hundred bucks for some bolts. I'm gonna have to go ahead and stick with stock.

I think I am going to set my redline somewhere around 6200 rpm. I'll see what I can do about the springs. The LS6 springs would be any springs on an LS1/LS6 that is 2002 or newer, correct?

Alright, so right now I need to:

Rebuild the stock short block - $600~
Get a new timing chain - $20~ (I've heard I just need the chain?)
New Pushrods - $100~
LS6 Springs - $??? Anyone know how much I can expect to pay for these?

Or I can just scratch the springs and pushrods until I swap out the cam. Hmm, this is a budget build after all...

Thanks for helping me figure all of this out fellas. =)

icedenali

It will take much more money than you think when you rebuilding LQ4.(need work, has potential of 500WHPwith stock internal easy.
How much HP/TQ are you trying to get? what is your budgets?

Top Secret

I don't see how it will cost more than I think it will. I was quoted 450 to assemble the block, plus about 40 for the bearings and 50 for the rings, and then tax from a shop. The guy said about 600 with hone.


Well, I have two "phases" that I want to do this in. The first phase is the initial buildup. Aiming for around 300 horse/ 300 torque. Essentially a stock LQ4 with a stock T-56 and the stock rear end. The second phase will have a more performance oriented build up. New springs, pushrods, turbo (Either MP T70 or S400 Borg Warner) + intercooler and an R200 rear end which can take about 500 torque. My end goal for this car is 500 hp and 500 torque.

But I would like to get through "phase one" in under 6-8 grand, car included. So far, I'm on track:

Stuff I Have:

Car: $1,300
LQ4: $280
Carb: Free
Battery: Free
Hoses/Clamps: Free (Have a ton)
Fuel Pump: Free
Tools: $200
Air Filter: $10
Plugs: $40
Sold L28 Engine: -$200
Sold 4 Speed Trans: -$100
Electric Fan: Free

Stuff I Need

T-56: $1,200
Radiator: $300 (Aluminum)
Drive Shaft: $100 (Have one, just need it cut to fit)
Intake: $340 (Victor Jr intake)
MSD Ignition: $200 (Control Box)
Short Block Rebuild: $600 (Local Machine shop quote for rebuild + tax)
Starter: $100 (Anyone have any for sale?)
Alternator: $100 (Anyone have any for sale?)
Coils: $100 (Anyone have any for sale?)
Mounts: $325 (JTR third gen mounts)
F-Body Oil Pan: $150 (Anyone have any for sale?)
LS2 Timing Chain: $40? (No I idea how much these run for)


That puts me at around 5 grand. Add in another grand or two for all the **** I'm not thinking of and problems I am going to run into and I'm right in the middle of my budget. =)

Stuff I need to sell:

15 stock injectors
8 Stock pistons with 22k miles on them
8 Stock rods with 22k miles on them
Stock truck intake
Stock Fuel Rails
Stock Truck Oil Pan

Hoping to get 300 or so from all that.

Once again, thank you all for your advice and such. It's really going to come in handy after the initial car is running and I start on the second phase!

blown3qtr

I would. Stock internals should be fine at 500hp and 6200 rpm.

Have you priced gaskets yet? Figure about $300 for everything. W/ 22k mi You can probably reuse some.

I'll post up a pic of the Lemans I hope I can find a digital one w/ it on the ground. It's been on jack stands over a year when I pulled the muncie 4speed. I'll probably slap it back together b4 the 408 swaps to get it out of the garage and drivable. Tranny really needs a rebuild but I haven't committted yet. 408 kind of took priority.