71 Chevelle 408 LSX build thread

[Chevelle598bb]

Here are some pics of my current GW set up with afco coils. The top shock mount is what I will cut out and replace it with a double shear mount for a coil over. I will also have to rebrace the upper control arm mount.

[ChevelleNV]

Glad to see those rear coil over mounts worked perfect for ya, cars looking sick...

[64Chevelle383]

I may have missed it, but just wondering what mounts and oil pan you are using for your build. Any idea if these would fit a 67 chevelle?

[Chevelle598bb]

Thanks Greg, they do fit great. Hopefully they will work as good as they look and fit.

I am using edlebrock Adapter plates, energy suspension mounts, short motor stands (stock 350 stands) and f body oil pan. I had to move the frame stands 3/4 inch back to gain oil pan clearance. The passenger side cylinder head is one inch from the firewall. Now I have plenty of clearance every where. I don't have headers yet so that maybe an obstacle. I'm not sure if this set up will work on 64-67 because I know the crossmembers are a little different.

[andrewb70]

The first big bump you hit with the rear will bend the bolt that attaches the lower part of the coil over to the axle bracket. You can't just space the mount out like that. Remember, that point was only designed for the shock mount, it was never designed to support the weight of the car. So now, in addition to supporting the weight of the car it is also spaced out 2 inches. All bad...

Andrew

[Chevelle598bb]

I was thinking of using the same mount location but reinforcing it with a bolt thru type mount.

[andrewb70]

I was thinking of using the same mount location but reinforcing it with a bolt thru type mount.

I am not quite sure what you mean. I would suggest looking at how some of the other coilover kits are attached.

Andrew

[dhutton]

A lower mount like this will be stronger and allow you to adjust the ride height:

http://cgi.ebay.com/ebaymotors/ws/eB...category=33582

Here is another option:

http://cgi.ebay.com/ebaymotors/Coil-...item3f0df55755

[Chevelle598bb]

The second link is essentially the same set up as I have now which is the lower mount just bolted or sliding on a stud. The bolt shear strength is the only thing that I am worried about with my set up. The factory brackets on factory rearends were made with thin flimsy metal or atleast it was on my factory 12 bolt. My current rearend is a Moser M9 and came with new brackets welded on from Moser. The lower shock/lower control arm mounts are 3/16 or 1/4 plate and are hydroformed. Super thick and sturdy. So the shear strength of the bolt like Andrew brought up is what I am thinking may be an issue. It would be very simple to make an outer portion that would weld to the lower control arm mount and make a "double shear" style mount for the lower coilover mount. Just like the aftermarket companies make but just not adjustable. Right now the ride heigth is where the coilovers need to be and I am happy the car's ride height.

[dhutton]

I think the issue is as Andrew said. You have the coilover spaced out 2 inches on that stud and it will likely bend and eventually break.

[Chevelle598bb]

Right, the spacer is an 11/4 inches and the current spacer is just something I had in my spare bolt bin. The permanent spacer will be .250 thick DOM tubing welded to the shock mount. I think with that and another bracket welded to the shock mount for support on the outside of the coilover will be fine.

[wing_0797]

Is that still fuel injected? if so how? I am running a 442 hood and it would be nice for the induction to work...

Now that the suspension is finished, I am now moving to onto the motor and trans. The motor is 408 ci, iron LQ4 block, ARP main studs, .030 over, align honed, Eagle forged 4.0 stroke crank, Eagle H-beam 6.125 rods, Diamond L92 pistons, F body oil pan, Corvette LS3 balancer, Melling oil pump, 2007 LS7 camshaft, LS3 heads, Comp 918 springs, trick flow pushrods, Comp billet timing set, factory rockers, LS7 lifters, Corvette accessory drive and GMPP single plane intake. When I purchased the LS3 heads, they came with a new LS3 intake. I was planning on using the intake but really want to use a factory cowl induction hood with a factory air cleaner. That would mean I would have to switch to a single plane intake. I then came across a fellow who wanted to trade so I then had my GMPP single plane. I then picked up a Holley billet 4150 throttle body. I kept the LS7 injectors I already had and made some brackets for the LS3 billet fuel rails I already had to work with the single plane. I know its kind of a mix and match of parts but I want a reliable and efficient motor with a stock style idle. It should make plenty of power and torque for what I plan to do with the car not cause any issues. I know I am leaving some power on the table without having a custom cam ground but I think the LS7 will do what I need it to do. For the trans I am using a LS1 T56 with a LS7 clutch/flywheel combo. I have the motor and trans mocked up where I need them but I still need to make a trans crossmember.

[andrewb70]

Right, the spacer is an 11/4 inches and the current spacer is just something I had in my spare bolt bin. The permanent spacer will be .250 thick DOM tubing welded to the shock mount. I think with that and another bracket welded to the shock mount for support on the outside of the coilover will be fine.

Okie dokie...I don't think that will do it, but it is your car.

Andrew

[Chevelle598bb]

Your right it is my car so I'll try it and see. If it doesn't work then Ill change it up.

[Chevelle598bb]

Yes it is still fuel injected. I am running an l92 gmpp single plane, Holley 1200 cfm 4150 throttle body, ls7 injectors, ls1 computer with a speed density tune.

[wing_0797]

That sounds cool, how dose all of that come together? like the setup, I know the fuel is supplied by the fuel rails I notice the throttle body has a pig tail.

Yes it is still fuel injected. I am running an l92 gmpp single plane, Holley 1200 cfm 4150 throttle body, ls7 injectors, ls1 computer with a speed density tune.

[Chevelle598bb]

It works pretty much the same as a stock intake. Fuel is supplied by the injectors and through the injector rails. The throttle body has the iac motor and tps sensor installed on it. The air intake temp is placed inside the air cleaner. The only sensor not used is Maf sensor. That is why you must run a speed density tune for your engine which is based off VE and throttle position instead of how much air is coming in the motor.

[andrewb70]

Your right it is my car so I'll try it and see. If it doesn't work then Ill change it up.

I just hope that when it fails it won't cause a wreck, that's all...

Andrew

[wing_0797]

Thanks for the info, Speed density I'll look into that...

It works pretty much the same as a stock intake. Fuel is supplied by the injectors and through the injector rails. The throttle body has the iac motor and tps sensor installed on it. The air intake temp is placed inside the air cleaner. The only sensor not used is Maf sensor. That is why you must run a speed density tune for your engine which is based off VE and throttle position instead of how much air is coming in the motor.

[Chevelle598bb]

Now I am in search of a front suspension set up. I sold my global west upper and lower arms, stock spindles and spring set up. After speaking with Marcus, I am looking at the SPC uppper and lower arm, ATS spindle, and QA1 17 inch coil overs with custom double shear upper mount set up and the Chassisworks G-street coil over set up with the tall spindle. I know the SPC and ATS will have better geometry and more adjustability but it is quite a bit more cash than Chassisworks G-street set up. Got some thinking to do. How much will I actually be driving the car versus autocrossing / road coarse. Right now definately more of a street car but would like the ability to run in some events if I want too. Plus my Z06 brakes bolt directly to the ATS spindles. I always find a way to justify the more expensive way to go.