Wicked Weasel

Update: 02/09/2008 - Car was on hold to finish customer cars, but now it is in full swing again. New Pics are up today. Engine is built and next week the old engine is coming out and the new going in


I am sure that many of the general CF people have never saw an engine build so we decided that we would document my LS7 build for my 01 C5. We are going to do our best to show pictures and explain what we are doing and/or why we decided to go one direction over another.

I will continue to update this thread on the progress of the build, but you can follow the entire build which includes commentary, pictures and research at

http://www.ecsracing.com/ecsracing/f...splay.php?f=77

Some Background

My last track day at WGI my timing chain went and it was time to make a decision on what to do with my car. My ECS H/C 346 had over 3 years of road racing and over 50 1/4 mile passes. I was not happy that a double roller broke causing me to make a decision on a new setup, but such is life and so the decision was to either try and fix what I have or look into a new engine. A new engine that sounds so nice (that was a quick decision )

Originally we were going to install a 402 in my car. ECS has proven success with this setup in different street applications, but ECS was concerned about an engine that is almost completely dedicated to Road Race Tracks (15-20 track days per year) surviving with a standard oil system so they started to investigate Dry Sump systems (there is a write up on Dry Sump systems at http://www.ecsracing.com/ecsracing/showthread.php?t=442 ).

At PRI this year Doug@ECS found a ton of valuable information on Dry Sump systems, unfortunately every system that he found would mean that I would lose the A/C which I was not willing to do (it is still taken on the street in the summer and I wanted A/C). Then out of no where thrown on the table was the LS7 setup. GM has already developed a Dry sump with the LS7 setup and we all know there is plenty of power on tap with a 427. I could also keep my A/C so we looked into it further.

Sure the GM LS7 dry sump solution is probably not as good as some of the aftermarket systems that Doug looked at, but after doing some research I personally felt the GM solution (with a few mods) would be more than adequate for what I do. Of course only time will tell if this is true or not, but many LS7 owners are happy with their cars on the Track.

Right now we are just starting to get parts in for the build. Here are some teaser pics (more at ecsracing) which should get your blood pumping:

7.0L BABY - Front



Where are we going to fine Pistons for this



Crank



Oil pan - dont need much with Dry sump

AU N EGL

Oh man Engine **** - bring on the pictures

Independent1

I always thought one of the big drawbacks to running a C5 on the track was the lack of a dry sump system due to all the high G-forces. While an accusump helps, it is a less than perfect solution. One of many reasons I decided one is better off with a true race car from the get go.

What kind of numbers are you hoping to get out of this motor? Planning on making any improvements to the driveline to handle the extra torque and HP?

95jersey

Bob, couple of quick questions.

Did you guys buy a brand new long block or did you get one used? I am curious as I am sure these things are now floating around US junkyards from totalled Z06's. It look like it had oil in the pan. I am curious as to what a used LS7 would go for nowadays. I think new they are $12k.

Are you going to use stock internals or are you going forged and all that? Did your block come with all the titanium internals or do you have to provide that extra?

Good luck with the build! With this motor and LG coils your going to be untouchable!

bowmanized

I was going to ask anyway, but what are the differences between the LS7 and other aftermarket setups?

Thanks for the pics

Wicked Weasel

In simplest terms the LS7 runs off the crankshaft while the others are mostly belt driven. The LS7 design allows me to keep the A/C.

With the LS7 I am also stuck with their 2 stage design (1 scavenge and 1 pressure) if I went aftermarket I could get more stages. Many I saw had at least 3 stage setup which would have 2 scavenge and 1 pressure section or a 4 stage.

Wicked Weasel

I am going to say 550rwhp for now . I am less interested in peak HP versus TQ and driveability, but we will see.

As far as drivetrain - I am going to upgrade to the Tex Exo-skel clutch. I already have 3.73 gears with hardened output shaft, RPM Tranny and I will keep the DTE Brace on. For now I am not touching the torque tube.

Wicked Weasel

I got a surplus LS7 block. It is new.

We will use the LS7 crank with forged Pistons and Rods. I did not go with titanium because frankly they are not easy to get and I didnt trust used.

We will also use ECS Custom NA Cam, Trick Flow heads, American Racing Headers, FAST 90/90 and whatever else I can throw in there.

John Shiels

I think you will need to dump the 3:73 rear no? Good Luck on the build. How much torque do you expect?

Wicked Weasel

I am not sure yet about the 3.73s. It only took a few times out though to know the 4.10s were no good with H/C setup so I am sure after WGI in April I will have a better idea. Luckily I can always find a 3.42 setup.

Over 500, but how much I dont know.

TRACKMAN2

in my best napelon dinamite voice.......lluccckkyyy

Dirty Howie

Good Luck

Could someone shoot me a PM .... curious about $$$$$$$$


DH

John Shiels

H&C 427 I'd be looking for 600 rwhp. I see 581/521 stock heads on the board here add heads and your at 600+ Tires will be going fast! What size are you going to run? I see many modded 427's in the NE this year Sure be fun. Doug making 427 or bigger?

DOUG @ ECS

We are leaving it a 427 John, we are also not going for max numbers, kind of building it like a boat motor. Made to make big power, yet be able to handle long periods of high rpm use. We are going more for the flat torque graph, rather than peak hp numbers. One of the diferences we do when building a road race engine compaired to a drag engine.

jtkeller

how do you solve the relucter wheel being different on the ls7 than what was originally in the car?

Wicked Weasel

They changed it back to the 24x versus the new 58x. If you look at the picture below you can see at the end it is the C5 reluctor and not the new LS7 one.

gkmccready

Do folks bother knife-edging and lightening the crank on these motors? The crank looks... heavy.

95jersey

Would that benefit a dry sump motor? There is not much oil in the pan.

gkmccready

Good point. I guess the knife-edge wouldn't, but the lightening must, right? Less mass to rotate?

jtkeller

I'm not familiar with changing the reluctor wheels - is that pretty easy (not too expensive) to do?