Wednesday, July 18, 2012

GM Performance Parts LSA

When it came time to figure out a powerplant for the OLC2 we knew that the new GM Performance Parts line of LS based engines was the logical choice.  The LS7 in the OneLapCamaro had been a great foundation for the '67 but for the '69 we knew that we needed more power.  The solution was the LSA Engine from GM Performance Parts.

With over 550 HP on tap stock and more than capable of making 700+ with some simple tweaks it was definitely the way to go.  For our purposes it was more than just a simple installation.  We wanted to set the engine back 5+ inches to give us a little bit better weight distribution.  That was about the max we could work with the SpeedTech Subframe and Torque Arm and going back that far required some serious reworking of the firewall.

We started by gutting the stock dash and cleaning up the cowl.


I would be lying if I told you that I knew why the decision was made to completely remove the cowl; unfortunately it was done before I knew it.  Now I tell myself that we're saving some weight while, in reality, I know that it's going to be a monumental PITA in the future.



But at this point it's too late to fuss over bad decisions.  All I can suggest say is "don't try this at home."

The Supercharged GMPP LSA is will be by Tremec's T-56 Magnum - the aftermarket version of the OEM TR-6060.  Rated for 700 ft.lbs. of torque it should be ideal for the OLC2.




A quicktime bellhousing is more compact and lighter than the McLeod piece we used on the OLC.


Locating the LSA back from it "stock" position required making some room in the firewall to get the lay of the land...


Back almost 5" from it's "stock" location the LSA needs some help around the firewall and at the subframe.



As always, there is more than one way to skin a cat.  I would consider this, in hindsight, to be the wrong way.  Too much time, labour, and headache to justify.  Once again... live and learn...

After some discussion the decision was made to remove the old firewall and replace it in it's entirety...




We began by removing the old firewall and started its replacement with a flat sheet of metal...



Getting a flat plane far enough back meant removing the factory "tulips" and cutting in to the structure



To give the new firewall some stability a bit of work was put in with a bead roller...


Before the flat panel was curved to replace the now missing tulips




Our LSA looks right at home with the very tidy firewall...



Repositioning the firewall meant repositioning the fender mounts as well - you can see that we're about 2" further back with the new firewall...


The engine setback also required some new clearances be made for accessories...


With some finish work the new firewall looks like it could have been like that way from the factory



To ensure that the LSA could make every bit of horsepower we went with a custom set of Stainless Works headers from SpeedTech.  With 1 7/8" tube they were only available unassembled...  Ironworks created a jig and welded them up in house...



 We're well on our way now...

Next up - the Roll Cage!







Friday, July 13, 2012

Making Some Room

With the SpeedTech front and rear suspension in place Ironworks went to work on the front fenders.

One of the biggest shortcomings of the original OLC was the restricted turning radius, narrow track width, and limited tire options which came a a result of the stock subframe and stock fenders.  The SpeedTech subframe would help with the turning radius and some of the tire size but to optimize the track width and get some really big tires under the front we needed to tweak the front fenders "a bit".

The '67 has been running a 275/35-18 front tire in combination with a 305 or 325/30-19 rear tire with the front track width being over 3" narrower than the rear.  OLC2 is going to run 305/30-19s front and rear with a balanced track width.  Follow along as we make some space...

Starting with the stock fenders...


Cleaned up and marked for preliminary cuts:


Started with three basic cuts...


Pulled out to ensure lots of clearance



Leaving the back of the fender well out from the door




The choice was old school IMSA style or some kind of transition in to the door... we chose the latter



Starting to look like something...




More transition work to come but it was getting close...



With the basics together the doors got some work to make the transition





Now we're getting a look at what the OLC2 is going to look like...





It still need "finish work" on the sheetmetal - gaps, fit, etc. - but we're on our way...



With the outside coming together it's time to turn our attention to fitting the GM Performance Parts LSA engine and Tremec T-56 Magnum...