My LQ4/T56 build thread

[ChuckLee]

Thanks for all the input.
I'm a little nervous about the vacuum issue I may very well run into as well. Having a manual will be helpful here I think. If I do run into this issue I will probably just try a vacuum canister and see what that does. If that doesn't work, I suppose a booster, although I'm not a fan of boosters.

[NC_John]

Originally Posted by ChuckLee

Thanks for all the input.
I'm a little nervous about the vacuum issue I may very well run into as well. Having a manual will be helpful here I think. If I do run into this issue I will probably just try a vacuum canister and see what that does. If that doesn't work, I suppose a booster, although I'm not a fan of boosters.

A wilwood manual master and matching brakes will work better than a power brakes setup without vacuum problems. Go look at road course cars and see how many power brake setups you find. I love mine.

[ChuckLee]

That's another option for me, Just HATE bending and flaring!

[NC_John]

Originally Posted by ChuckLee

That's another option for me, Just HATE bending and flaring!

Me too. I ended up going with Ni-copp lines and used a snap-on flare tool but it was still miserable. I'd love to have somebody come over and redo my lines nicer.

[solidaxel]

Originally Posted by NC_John

A wilwood manual master and matching brakes will work better than a power brakes setup without vacuum problems. Go look at road course cars and see how many power brake setups you find. I love mine.

What makes the Welwood master better than the others on the market?
Have you looked at a Hydroboost set up?

[ChuckLee]

I had a couple cars that had all Wilwood brakes honestly I was really unimpressed however They have changed a lot of their Products since then so maybe they are much better now. Personally, the best brake set up I ever had was Baer setup in a 240SX with an LS3 swap

[NC_John]

Originally Posted by solidaxel

What makes the Welwood master better than the others on the market?
Have you looked at a Hydroboost set up?

They are used in about every form of Motorsport and engineered for performance, feedback and a responsive feel. OEM systems are not.

And IMO way too much ugly plumbing on a hydroboost. I deal with enough of those on the diesels and work.

[NC_John]

Originally Posted by ChuckLee

I had a couple cars that had all Wilwood brakes honestly I was really unimpressed however They have changed a lot of their Products since then so maybe they are much better now. Personally, the best brake set up I ever had was Baer setup in a 240SX with an LS3 swap

I called wilwood directly, told them what I was trying to do and went with exactly what they told me to get. A completely matched system. I am extremely pleased with how it works, and this is just with the inexpensive d52 calipers. I can't wait to upgrade and really get into the good stuff.

[ChuckLee]

shoot us the part numbers you ordered John, would like to research them. I'm not opposed to manual conversion, and definitely not opposed to going hydroboost either. My thought was to just run it as is, and if my vacuum issue really affects my braking, then I would deal with it then.

[ChuckLee]

Started running fuel line and mocking up filters and pump.

Untitled by FlickrAccount83, on Flickr

REALLY need to locate some connecting rods.......that's the only thing holding me back at this point from engine assembly and giving the drivetrain a final destination.

[KenAdams]

Subscribed . See you at the track!

[ChuckLee]

Good meeting you the other day Ken. Your suspension setup is so nice looking! Let me know when you go i would like to watch.

[ChuckLee]

So out of curiosity I threw the truck on the lift to determine what my rear end gear ratio currently is. Are you ready for it.....

1.60:1

No this is not a typo....it's somewhere around

1.60:1

Lol, this can't be right! Well, looks like I need to get some gears! Any recommendations on gear ratio, locker/posi type and brand for my setup?
(F body T56 with 275/40/20 tires for cruising around town and having general fun)
I wonder what RPM's I'll be doing at 70mph with 4.11's in 6th gear?)

[sangell]

ChuckLee,
Something is wrong there, 1.60 is not what is in there. I'm not saying that's not what you came up with but your method is flawed.

There are a number of RPM calculators in the web that will allow you to determine the rpm at any speed you want. You will need to know your tire height in inches and your 6th gear ratio which in an F Body t-56 should be a .50. Things to watch for are driveshaft rpm as they get out of hand quick with these double OD transmissions. If your tire is 27-28" a 3.73 or 4.10, if it 28-29" then 4.10-4.56 works well. Like I said watch that driveshaft rpm and it's speed is simply the given rpm of the motor divided by .50 in your case so you can just double the engine rpm. You will end up around 3700-4200 depending on your new gear ratio and not just any shaft will handle that speed.

[ChuckLee]

I agree with you, I must have done something wrong because never have I heard of such gearing, lol. I did what I always do, jack rear off ground, use chalk to mark top of tire and two chalk marks at rear end (one on pumpkin which is stationary, one on rotating yoke). The yoke turned approximately 1.6 revolutions to the wheel's 1 full rotation. I have two ideas:
1) I have no transmission or DS installed. That's first time I've checked this way w/o Trans installed. Isn't that irrelevant though? I'm not trying to figure out what gearing is in trans, simply a "neutral" situation/scenario to see what the gearing is in the rear.
2) I have an open diff I think and I wonder if maybe that is playing a roll? I don't know.

I seem to recall checking this while I had the truck all together with a T5 and 355 in it and I believe I checked it in neutral and came up with something like 2.60 or 2.75 or something to 1. As you can tell by now by reading my thread, I'm learning, and loving learning. I'm not afraid to make myself look like a total newbie for the sake of your pleasure and others' help. Lol

[ChuckLee]

Ordered some Forged I beam connecting rods today, then saw a deal on new, stock Gen IV rods. I have to decide now if I want to use the stock GM rods which are good for much more power than I'll throw at it, or if I should spring and spend more money on going with aftermarket pistons to go with the 6.125" Forged rods. I'm using ARP 2000 rod bolts either way, and the issue isn't HP here because both will handle my HP no problem. The issue is RPM's for sure, and my cam and heads are very happy in the 7000-7200rpm range.

[sangell]

ChuckLee,
You are doing a great job and your truck is bad ass, we are all learning as we go and even if you have done a bunch of these trucks you should learn something new with each one.

As for the rods go with the forged ones, RPMs are cool

As for gearing here is what I came up with.

275/40/20 tire= 28.66" tall.
F-Body T56 if stock has a .50 first gear.
4.11 gear at 75 MPH= 1807 engine RPM and 3614 DS RPM.
4.56 gear at 75 RPM= 2005 engine RPM and 4010 DS RPM
4.88 gear at 75 RPM= 2145 engine RPM and 4290 DS RPM

With that I would prefer the 4.88s with you having a motor built to make power in the upper RPMs. The issue is drive shaft speed of 4290 is spinning it pretty fast, if a long bed you will need a two piece for sure and even at that it will need to be built right, if a short bed you can try a one piece as I am. My set up puts my drive shaft at 3830 RPM at 75 MPH and I went with a 4"x.085 wall steel driveshaft.

[sangell]

From Mark Williams site

[ChuckLee]

Good info there. thank you. What did that set you back for that DS? I'm longbed, so I want to stay two-piece for multiple reasons. Honestly, I hadn't thought much about DS yet beyond length/fitment. Originally I planned to utilize the stock 2-piece DS and just have it fitted to length. I wonder if anyone has done that, or what power it is good for?

[sangell]

It was $450 but it has the slip yoke in the shaft so that added some cost. Mine was built using 1350 series ujoints, I needed an adapter for the stock flange on the trans then I needed a 1350 series pinion yoke so I got a forged one. All in all it was about $650 but it is a very strong set up that handles the RPM. As for the two piece you will be fine as long as all of the angles are correct, as you can see in the cart I posted the shorter in tube length you go the critical speed goes up a lot.

[ChuckLee]

Look what I got
Untitled by FlickrAccount83, on Flickr

Only need the passenger side fender, the driver side will be sold for $100 or it will be my little boy's wall art in his room.

Untitled by FlickrAccount83, on Flickr

[KenAdams]

Saw the pictures of the cut fender with the clamp, but didn't see an explanation? What happened?

[ChuckLee]

E brake failure on my driveway. Truck rolled down embankment and thank the Lord my children were inside. God grew a nice big tree in a special place to stop it, although a natural truck ramp would have been nicer. Ate up the front of truck and pushed fender into door, yada yada. I'm just glad I have friends like you to remind me of the high points in my life.

[snipescastle2]

If your looking for an easy remedy for low Vacuum, I found an electric Vacuum pump off of an Audi A4, that had a Diesel engine in it. Cost me $25 at the local pick n pull. It's normally controlled by the cars ecm, but I wired mine up with a digital timer module to run for 2 minutes then shut off, or until I hit the brake pedal. This Vacuum pump makes 25" of Vacuum all day! It will get hot if it continuously runs though, (that's why I chose a digital timer module to control on/off cycles) I also found a 2 pound Oxygen cylinder that I stripped the green powder coating off and chucked it up in a lathe and polished it up, I'm using that for a Vacuum reservoir. I haven't had any problems stopping whatsoever. Just an idea.
Have a good one!
Ben

[snipescastle2]

If your looking for an easy remedy for low Vacuum, I found an electric Vacuum pump off of an Audi A4, that had a Diesel engine in it. Cost me $25 at the local pick n pull. It's normally controlled by the cars ecm, but I wired mine up with a digital timer module to run for 2 minutes then shut off, or until I hit the brake pedal. This Vacuum pump makes 25" of Vacuum all day! It will get hot if it continuously runs though, (that's why I chose a digital timer module to control on/off cycles) I also found a 2 pound Oxygen cylinder that I stripped the green powder coating off and chucked it up in a lathe and polished it up, I'm using that for a Vacuum reservoir. I haven't had any problems stopping whatsoever. Just an idea.
Have a good one!
Ben