Exhaust question, just curious.

[Doug S.]

I notice nobody is using a "Bundle of Snakes" exhaust on the SLCs.

Just curious why not?

Not enough room? Not the best choice for the LS series engines I see most of y'all using? LS firing order not right for that design?

I know there has to be a simple reason...just have not seen the issue addressed.

Thanks!

Cheers!

Doug

 

[Jac Mac]

LS motor has same firing order as late small block fords and 351c Doug. In the case of the SLC it would appear space for 180° crossover exhaust options were not high on the priority list!

 

[Matt K]

Someone did. I don't think it was an LS but there are major issues fitting the 180s in the engine bay and the excessive heat they generate causes a bunch of problems. It's possible for 180s if you're willing to sacrifice but most who have seriously considered it have decided not to for the many, many drawbacks associated with it.

The GTR has much more room. I have a feeling we will be seeing 180s there…

 

[Matt K]

Found it…

Good thread
http://www.gt40s.com/forum/slc-clubhouse/29390-sl-c-powerplant-possibility-14.html

 

[Howard Jones]

Mine is going to get a "H" pipe eventually but doing a 180 set isn't worth the effort. Just not enough clearance between the big brace and the bodywork or alternately between the big brace and the gearbox.

If might be possible to do a set without mufflers or maybe place the mufflers behind the car but it would be ugly.

I even spent a few hours mocking up a set of braces out of plywood to make room a couple of years ago but in the end I didn't think that they would provide enough rigidity.

The engine room is perfect for a set of 4 into 1 forward swept sprint car type headers, so it just doesn't make much sense to force a round peg into a square hole.

 

[Doug S.]

The engine room is perfect for a set of 4 into 1 forward swept sprint car type headers, so it just doesn't make much sense to force a round peg into a square hole.

Makes sense, Howard! I am just a fan of the "look" of the BOS headers and thought that they would be a natural for the SLC, but I can see that the issue is room and heat. Is the fiberglass on the SLC (since it is "Super-lite") thinner than on the RCR40? I've heard of people having their rear clamshell "sag" from excess heat on 40's, so if the fiberglass on the SLC is thinner, it would heat up and sag much easier.

It seems like there are MANY reasons that the BOS headers aren't really the best choice for the SLC...and I do agree about the LS series of Bowtie engines....they have great reputations for both making power and reliability, so why jeopardize that?

As the adage goes, “there is more than one way to skin a cat.” Several years ago, Burns Stainless was working with a NASCAR Cup engine builder to develop a 180 degree header (pictures above) that would work with a stock car. The design shown in these pictures was developed that crossed the tubes under the engine. A special dry-sump oil pan was designed for the necessary clearance. Initial testing was promising, but as it goes in racing, rule changes made the header illegal for NASCAR."

I once shoehorned a 351C into a '72 Mercury Comet (much like a Ford Maverick). A couple of the tubes on the custom headers required for that swap crossed over under the pan, behind the sump...much like those we see in the picture above.

Speaking of 351C's.....that engine in the original post looks very Cleveland-like...the valve covers, particularly....the 351C is my favorite of all the Ford engines.

Cheers!

Doug

 

[kris]

Doug: do you mind if I expand your question a bit?

There are a number of SLCs configured with side exhausts, and I wondered if those folks might chime in with the pros/cons they've experienced with that setup -- I'm thinking of going that route and would very much appreciate any feedback you may have (at least one of the RCR cars is configured this way too)

 

[Jack]

Pretty LOUD. You may be able to fit a 6" muffler in there, forget about cat's though unless you do some creative back-and-forth plumbing. Perhaps someone else can chime in here.

 

[Ken Roberts]

Grant did side exhaust with larger mufflers . I don't know if he's got it running yet.

http://www.gt40s.com/forum/slc-clubhouse/38866-grants-sl-c-build-tread-2.html#post392863

 

[kris]

Thanks Ken & Jack

Looks and sounds like Allan installed side-exhausts on build #7 (first drive, first start) though unfortunately it's not possible to see what size those mufflers are; perhaps Allan or JK will chime in here

Grant's setup looks like it does the business, and those mufflers apparently do remain cool