Kurt H (hoffkm) SL-C build thread

Pulled the intake off the engine today in preparation for the FAST intake that is arriving tomorrow according to Fedex. Guess the delivery guys are working overtime on Sunday for the Christmas rush. I salute them all for their hard work in this busy delivery season!

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Gained some more "wall art" for the workshop!

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Installed the FAST LSXR 102 this week. Once again waiting for my car with nothing to work on.

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This is a much nicer piece than the LS2 intake, thank you Ken for the suggestion. The intake volume is this thing is HUGE plus the runners and overall inside is so much "smoother" than the stock intake. Downside is my thottle cable bracket is going to be a lot more difficult to fabricate now due to the side of the manifold but I'll figure it out. That is what Mechanical Engineers do!
 

Ken Roberts

Supporter
Intake manifold looks great Kurt. While you are waiting you could work on the transitions at the base of your LS7 exhaust manifolds. You could buy a pair of 90 degree 3" mandrel bent tubing and section it like in the picture then buy a 12"x 12" sheet of stainless to fill in the sides. I used this technique to make a couple of sets with the flanges and now I'm going to make two more sets without the flanges. The easiest way to fill in the sides is to overlap them a bit. Then you only need to make one template for all the sides. I chose to make each side flush for a better look but it's a horrendous amount of work.



The H Craft...overlap style

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Ken,

That is the exact plan for my exhaust and I have all the materials here. Was waiting to have the car here before I started cutting and welding to make sure everything fits around the frame rails. I have 180 degree bent tubes to transition the inner side of the bend up in a smooth arc. Need the frame to determine exactly what angle to cut the 180 degrees down to (probably somewhere around 135 to 145 I’m guessing) to send the muffler exits out the center of the rear clam vent openings.
 

Ken Roberts

Supporter
If you plan on pushing the car hard at times and without a dry sump I'd seriously think about an oil pan baffle. Cheap insurance when you consider the cost of replacing an engine. LS engines don't like long sweeping left hand turns.

Did you keep the exhaust flanges you cut off the manifolds Kurt?

 
If you plan on pushing the car hard at times and without a dry sump I'd seriously think about an oil pan baffle. Cheap insurance when you consider the cost of replacing an engine. LS engines don't like long sweeping left hand turns.

Did you keep the exhaust flanges you cut off the manifolds Kurt?

I had discussed the LS oil starvation issue with Fran and his thoughts were unless you are racing aggressively adding an extra quart of oil to the Corvette pan is sufficient. My pan has a low oil level sensor that I am wiring to a warning light in the center of the dash. I may wire it to an engine kill relay to be extra safe.

As far as my LS7 exhaust flanges, unfortunately they went to the metal recycler when I recently cleaned up my shop after finishing the GTO. They had broken studs in them so I saw little value in keeping them around.
 
Have managed to find some "shop time" over the Christmas break. Got a start on my exhaust and have designed and made some coil covers. I will make my first attempt at the carbon fiber skinning process on these once I verify they fit in the chassis with the engine (thank you Cam for the inspiration!!). I'm a little rusty with my stainless MIG welding, by the time I finish these I'll be all practiced up. Nothing a little grinding cannot fix. I plan to glass bead blast these, give them a light polish, and wrap the pipes in header wrap so all the welds will be hidden. They need to be more functional than pretty.

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I never thought of 3D printing coil covers, that's awesome! Those came out great, sort of wished I'd thought of it before getting the C6 FRCs. Icing on the cake is skinning them in carbon, I may have to borrow this idea from you instead of smoothing painting my C6 FRCs body color.
 
I've never done any actual testing, but always been afraid that PLA or ABS parts would warp due to the heat under hood. Are you planning to keep the 3D printed cover or just use it as a buck to make carbon fiber ones?
 
I've never done any actual testing, but always been afraid that PLA or ABS parts would warp due to the heat under hood. Are you planning to keep the 3D printed cover or just use it as a buck to make carbon fiber ones?
ABS430 was used for the 3D printing and I plan to keep it for the base structure of the carbon fiber skinned part. ABS430 is good to 206 degrees F and is printed in a 230 degree F environment in our printer. Not a large factor of safety here for max temp but it’s worth a try in my opinion. The epoxy resin may be more of an issue, it is only rated for 150 degrees F. I cannot find a clear high temp epoxy.
 

Neil

Supporter
Clear epoxy has less strength and UV resistance than opaque epoxies. The fillers in the resin strengthen them very significantly. "Five-minute" epoxy is handy for many things but you sacrifice some properties- they are usually very brittle.
 
Been away from welding up my exhaust for a few weeks helping my youngest brother out by repainting a motorcycle for him. We have it all in primer, block sanded, and ready to apply base coat, clear coat, graphics, and final clear this coming weekend. Got back on my welding tonight. Still have some grind work to clean things up then the first one will be ready for the DEI header wrap. I just wish MIG welding stainless wasn't so messy but I do not have a TIG, nor the skills.

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Glass beads in my blast cabinet leaves a nice finish on the stainless, I think I'll leave them that way instead of polishing them. They will turn brown from the exhaust heat anyway.
 

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