Exhaust conundrum

[msg]

I used to have a set of headers and dual exhaust that were on an old 350 I am replacing during my rebuild. This time I have decided to go ram style exhaust manifolds on an L31 I installed. The truck isnt complete, just a cab with nothing but paint and metal. Not running yet.

Im new to this and trying to get the exhaust planned and estimated for a local shop to do for me. I thought maybe I could reuse what I have just to get down to the shop about 3/4 a mile away. Plus the crate motor is sitting in it and brand new, so I thought I would need to break it in and get it going first and then have the shop take it to deal with the exhaust.

I called the shop and the owner asked if I was going to cut holes in the crossmember to run the exhaust through. I hadnt thought of it. I am keeping the suspension at stock height so I wasnt planning to get fancy but he said it would help clean up the profile by not having the exhaust run so low but be further up. He said it would have less bends to making it easier and a bit cheaper. I am not sure what might be best. Ill attach some pics of where I am and where the old exhaust was before.

If anyone has any advice on what would be a good approach with what Ive got going please share your thoughts.

Here is where I am with things and the ram style manifolds I have.

[msg]

The old exhaust has been sitting outside for a few years since I removed it

[msg]

the old headers and the way it was running underneath before.

[AcampoDave]

My pipes run just like the the ones in your pic. Outside the frame. However, since I already have ramhorns mine cross under the frame closer to the front wheel where there is more clearance. It avoids the whole crossmember deal, but makes it virtually impossible to put in an "H" pipe.

[62bagger]

I was planning to run the exhaust outside the frame on my 62 and was hoping to have the room for an H pipe. What is blocking you from installing one? Since my truck is not finished I am looking for information. Is it the cross bracket that goes under the trans that is in the way?

[msg]

Looks like I have more things to consider than I realized. I just thought run the biggest pipes that make sense and put it together with some mufflers. Saw this video about x vs h pipes and my first step I guess is to learn more about my engine set up and decide whats best.

https://www.youtube.com/watch?v=Dd43rwLHEW4

I bought an L31 brand new and an edelbrock intake with some Summit ram horn exhaust manifolds. The trans is a 700r4 and the carb is a quadrajet I had before that ran fine. Im just out to cruise in the end, not a hot rodder or speed junkie.

The muffler shop owner said he would run the pipes through the crossmember if it were his truck, just so they didnt ruin the profile of the truck. I never noticed mine before looking bad but what do I know. I guess the pipes 90 degreed in front of the rear tires may not look as good, never thouht about it.

[AcampoDave]

In my case I ran the pipes outboard because I wanted the system to be tucked up with next to nothing below the level of the frame rails. Getting from one pipe to the other would require the cossover to dip below the bottom of each rail making it the lowest point of the entire system. I am just not ready to make that kind of compromise in an effort to gain a few ponies. I dont want to see it hanging under there nor risk it hitting the ground on steep driveways or speed bumps. Edit. If you look at the truck in the background it's run the exact same way. According to every mock up I tried, the crossover pipe would even be lower that the bellhousing crossmember. Even if I tuck it right behind the bellhousing it's still just gonna be a bear to work with being right under my clutch. Edit:Perhaps having an X frame and an automatic may give you different options.

[AcampoDave]

I watched these 2 Enginemasters videos when I was considering my exhaust and found them quite enlightening. The dyno doesn't lie.
https://www.hotrod.com/articles/engi...-inch-exhaust/
https://www.dailymotion.com/video/x5s8nr8
This one too
https://www.hotrod.com/articles/engi...rs-episode-17/

[62bagger]

Thanks for the info. I watched both videos and the difference for the H and X pipe is not worth chasing. I am planning on about 350+- HP Not 500. Good information

[AcampoDave]

Yeah, i thought it interesting that the Summit video you posted has the guy saying that motors need a certain amount of back pressure and yet the dyno pulls in the second and third Engine Masters videos that I posted completely disproved what he was saying.
You live pretty close to me. Maybe one day after this whole Covid thing blows over we might actually meet up at an event somewhere. We used to have some great c10 barbeques at Mickie Grove Park. I'm looking forward to returning to those again someday.

[62bagger]

That would be great.

[PGSigns]

I have a L31 in my 66 and run single exhaust. 2 1/2" off the headers to a merge I built to a 3" single into a 50 series flow master. Then out the muffler and out to the side in front of the rear wheel. After the muffler I have a 3" 45X4 1/2 section of nascar style oval. Got this idea from my race engine builder. works great and sounds awesome.
Jimmy

[msg]

Thanks Jimmy, any pics you can shore of the set up? I wonder if the ram style manifolds would do as well.

[1998c1500]

yep

[sirJim]

This is the way I did it on my 62.

[msg]

Very cool SirJim, the pics are great to see! Last go round I had the dual exhaust muffler set up but now I am wondering if the set up like Jimmy mentioned would be good for me and my application just cruising and not racing or anything.

[AcampoDave]

Wow, nice work with the mandrel bent DIY kit SirJim.
I did that too. It's fun, but a bit tough on the ol'body doing it in a regular garage.
Hats off to you on a nice layout.

[sirJim]

Originally Posted by AcampoDave

Wow, nice work with the mandrel bent DIY kit SirJim.
I did that too. It's fun, but a bit tough on the ol'body doing it in a regular garage.
Hats off to you on a nice layout.

Thanks Dave
We kind of have to do with what is available here and with the rules of keeping everything "original" makes it challenging to say the least. Transportation over the pond adds to price on everything. The Mandrel bent stuff is readily available and when going up in size the farther back we went works great, and sounds good too. Where in the central valley are you at? I am from Reedley before I Settled here in Denmark.