Good evening ladies and gentlemen....i need your experiences and opinions. Lloyd Elliot is porting my heads and Stealth Ram and has already recommended a cam for me. IIRC he said a 231/239 cam and around .580/.601 lift. It looks similar to the Lunati Voodoo cam which a member has on here and one a 355 M6 guy has on ls1tech. Needless to say I am excited because jumping from a 224/230 cam to this cam will put a smile on my face.

I am junking the hedmen 1 5/8 longtubes and going with Dyno Don shorties with dual 2.5 inch cut outs.

I'll see what the dyno says but possibly going from my 3400 stall to 4000 stall...STR of maybe 2.4? EDGE most likely.

Now....opinions guys....I THINK the dual cut outs will suffice. The guy on LS1tech dyno'ed at 422rwhp around 6200 RPM. I think since I have more cubes and he has the M6, they will cancel each other out in regards to dyno numbers but I think I'll peak around 5800 RPM.
But I am debating between the Speed Engineering true 3 inch duals for LS1/LT1s and having an exhaust shop make it work OR Hawks 4 inch Sinister exhaust with a Hooker Maxflow muffler (wished there was a 4 inch Aerochamber muffler)

 

Are you tryin to go over the axle or dumps? Why not just go to long tubes? I made my own 4 inch with a dynatech muffler. I love it, but I doubt I’m at the power you are

 

You want to run all that cam and head work through shorty exhaust?

 

https://www.thirdgen.org/forums/exha...long-tube.html

https://www.thirdgen.org/forums/tpi/...ip-into-2.html


First post compares a slightly modified Dyno Don short tube header vs 1 3/4 longtube on a dyno

Second post is a member who also ran Dyno Don headers and a 3.5 inch cutout with success. Both members are at my power level. So yes, I will give up the 20 hp from 2000 RPM and the 10ish HP at 5000 for better ground clearance.

 

See above posts. I also do not want to give up what little bit of ground clearance I have now for the slight horsepower I would gain from scraping on all the speedbumps and my inclined driveway.


Edit: I do not know how to weld, however, I am not against going to a diesel truck exhaust place here to make a 4 inch exhaust either...that is also an option. But since that would be a custom job, each member who made their own 4 inch fatback would have a different ground clearance, which is important to me.

 

The ebay longtubes look to have good ground clearance.

 

🙄

Ok I will say this in caps because it seems people cannot read...I WILL NOT BUY LONGTUBE HEADERS! THIS THREAD IS FOR THE SPEED ENGINEERING TRUE DUALS OR 4 INCH EXHAUST ONLY!

 

After building my own, ill say your better off buying the sinister. Ididnt save anything building it other than I wanted dual outlets. Its gonna come down to your personal sound preferance

 

Do the single 4". I have don's headers on my 383, using the mufflex 4" (same as the sinister) with a spintech muffler. It sounds amazing. My car sits pretty low, but overall, the ground clearance in manageable, all things considered. You'll need to get a panhard bar drop bracket/brace for it to clear, and it does run extremely close to the fuel tank. I added some heat shielding to my tank to help it out some.

 

Either system will suffice, since your choking point will be the y-pipe. Not sure how well a true dual system would work on a shorty set-up. Seems like there would be some wonky fab work to make it work. I'd just go single exhaust.

 

Either exhaust will work. I would do the one that you think better fits in your car. If you go with a single exhaust then I suggest using a Flowmaster merge to get the most out of it. That means you'll be making a custom Y-pipe, but you'll be doing that anyway if you want things to work well.

If you haven't bought the headers already then I'd do the long tubes hands down. 30 lb-ft difference in the link you provided earlier. That's a lot! No reason why you can't have good ground clearance with long tubes, just buy smart.

 

Especially since hooker will be coming out with SBC long tubes.

 

Already bought Dyno Don's headers. Could I sell them and get the Hooker yes, but this isn't a longtube vs shorty header thread which it turned into. Hence why I was pissed. This is me inquiring about the quality of two exhaust after the headers.
30ftlbs of torque difference? Where? At 3500 RPM where I will launch from? And then that's it...a lot of PITA work for the launch which i believe will be negated (at least partially) by upgrading stall to 4000 anyways. Thinking 2.4 str

 

Another option is a single 3.5" exhaust. Little easier to package and doesn't require reworking the panhard bar.

 

I did consider that, however, the Mufflex 3.5 exhaust is more expensive than a Sinister 4 inch and a Hooker Maxflow 4 inch. The only good thing about a 3.5 inch exhaust is that I could run a Hooker Aerochamber....I love the Aerochamber. The Maxflow is ok IMO but I love the sound of the Aerochamber.

Also, I am considering the option open of running a 100 wet shot and do not want to buy another catback if I decide to put the nitrous on there.

 

What do you mean "will be coming out with SBC longtubes"? Hooker already makes the 1 3/4 longtubes. Unless they are coming out with a 1 7/8 longtube.🤤

 

Sorry I should have elaborated. They will be releasing a new set that follows the Blackheart line and will work with their Blackheart dual system. They are much better designed to allow maximum ground clearance. There are a few threads on here where a Holley rep details these.

 

I won't get into the long vs short debate as I respect your request not to.
Regarding the 30 ft/lbs difference though, it's more like 30 X 3.06(1st gear) X 3.73(rear gear) at the launch. That's an additional 342 ft/lbs to get your car rolling. And the 30 ft/lbs doesn't account for any tuning (if my recollection of the posted threads is accurate). Just the header comparison.
All of that said, I think the reference to personal choice especially regarding the overall sound quality, both in tone and volume, will probably be a determining factor.

 

There's a member here by the name of firebrdo88 that runs 9's through a 3.5" exhaust with a 200 shot of nitrous. Got to be putting down a good 700 RWHP.

 

Goin back through this, no matter what direction you go, your gonna have some fab work. Hope you have a good exhaust shop available

 

Me too. Being as I am now in NC vice NOVA, I need to make contacts on who can do good work.

 

I appreciate that good sir. There are a few factors why I am going shorty...one I don't see the performance as being that much difference (opinions and I respect yours), ground clearance and the fact that my driveway is on an incline. If I was made of money or the Marine Corps paid me enough, I would do back to back not only dyno's but runs at the track. Having to have catalytic converters for the visual state inspection is also a factor. The exhaust shop that did the custom y pipe for the Hedman longtubes did not do a great job but it was the only shop willing to tackle the job so I was kinda stuck.
my goal with the car was originally mid 11s (11.7x to 11.5x). If I only get to 11.8x it's meh. I'm not going to professionally race this or anything. It's more of personal pride than anything.

 

Fair enough.

 

but will they work with the manual cars? Someone needs to figure that part out. I’ve got an LT1 T56 in mine. Running Dyno Don headers right now but I’m limited to either the stock or a $300+ canton oil pan and you can see the y pipe from the side of the car. No a huge fan of that.