ArdWrknTrk Posted July 31, 2020 Share Posted July 31, 2020 Jim, agreed on all fronts, the joys of this forum, everyone so helpful! I definitely like the look of dual exhausts, currently Espy has duals exiting behind the rear axle, I like that look. Making a note on the "2 1/2" collectors and a 3" tailpipe", where do you source such items and appropriate headers? Sorry for the dumb questions. As always I am learning as I go here, never done this stuff before. I'd say those dimensions are an absolute max given your engine and intentions. If you're going duals 2 1/2" exits would be my max, and maybe 2 1/4 system to 2 1/2 resonators or tips. As I said before, a consultation with your engine builder will reveal a lot. Sometimes the biases of the builder... But they are never going to suggest anything that would make the build you've discussed look bad. Gary has publicly dealt with both Tim and Scotty. These guys are awesome! Both placing in Engine Masters, and both not corporate shills. While I don't know their equal in the Windsor world, you can get much better advice than mine. I hope your planning pays off. Link to comment Share on other sites More sharing options...
Gsmblue Posted July 31, 2020 Author Share Posted July 31, 2020 I'd say those dimensions are an absolute max given your engine and intentions. If you're going duals 2 1/2" exits would be my max, and maybe 2 1/4 system to 2 1/2 resonators or tips. As I said before, a consultation with your engine builder will reveal a lot. Sometimes the biases of the builder... But they are never going to suggest anything that would make the build you've discussed look bad. Gary has publicly dealt with both Tim and Scotty. These guys are awesome! Both placing in Engine Masters, and both not corporate shills. While I don't know their equal in the Windsor world, you can get much better advice than mine. I hope your planning pays off. Don't undersell yourself there Jim! Not sure where to get the engine done. I do know I want it to be local. Right now I am leaning towards a rebuild by a local shop. Plan B would be a crate engine. I have time to make my mind up. As much as I want to build an engine, I just don't have the experience or anyone in my friend circle that does. So maybe next time.. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted July 31, 2020 Share Posted July 31, 2020 Don't undersell yourself there Jim! Not sure where to get the engine done. I do know I want it to be local. Right now I am leaning towards a rebuild by a local shop. Plan B would be a crate engine. I have time to make my mind up. As much as I want to build an engine, I just don't have the experience or anyone in my friend circle that does. So maybe next time.. But you have US. 🥺 Really. Just make some goals or needs and refine from there. I've always caught a lot of flak because I say you have to consider everything as a system. Choose every component to not only work toward that goal, but to work together. You want a 351 that makes 350/350 and has a broad power band? Link to comment Share on other sites More sharing options...
Rusty_S85 Posted July 31, 2020 Share Posted July 31, 2020 Were your short headers like these that I have? I personally wouldnt run long tube. Every long tube ive seen installed on these trucks hang down below the crossmember. The ones I got uses the OE ball flange for the OE 2 1/2" Y pipe which will provide a better seal than the paper gasket flanges of yesterday. Link to comment Share on other sites More sharing options...
Rusty_S85 Posted July 31, 2020 Share Posted July 31, 2020 Your questions are sensible, as are my replies. You like the look of stainless long tubes. Keep the diameter small and be aware of clearance to front driveshaft and transfer case. At least you don't have to think about a slave cylinder, like Gary. Do you think you want true duals? Are you willing to give up that space? Or do you just want a mellow sound and no restriction? Given your post I'd think 2 1/2" collectors and a 3" tailpipe at most. My 460 works well with this and a 750 CFM Holley carb. Anything more is WAY too much on a 351 (imho) Hell stock 351w`s used a single 2 1/4" tail pipe after the muffler with the pipes being 2 1/2" before the muffler. That should be a good starting point for any 351w long as you are not turning more rpm than stock. I stuck with that size layout as I myself am doing a 306 build which I think 2 1/4" tail pipe with the rest being 2 1/2" should be about right for a 6,000 redline. Link to comment Share on other sites More sharing options...
Gsmblue Posted July 31, 2020 Author Share Posted July 31, 2020 Hell stock 351w`s used a single 2 1/4" tail pipe after the muffler with the pipes being 2 1/2" before the muffler. That should be a good starting point for any 351w long as you are not turning more rpm than stock. I stuck with that size layout as I myself am doing a 306 build which I think 2 1/4" tail pipe with the rest being 2 1/2" should be about right for a 6,000 redline. Oh now, the headers I have a work of art, just don't try removing spark plugs or even the leads! Here is an old pic, as the truck is still in the shop I can't get any new ones for a while.. They have "Edlebrock" on the side but I have never been able to work out what design they are, or why they are so crazy looking. If you know why they are like this, please let me know! Link to comment Share on other sites More sharing options...
FuzzFace2 Posted July 31, 2020 Share Posted July 31, 2020 Oh now, the headers I have a work of art, just don't try removing spark plugs or even the leads! Here is an old pic, as the truck is still in the shop I can't get any new ones for a while.. They have "Edlebrock" on the side but I have never been able to work out what design they are, or why they are so crazy looking. If you know why they are like this, please let me know! From the look of the picture they would be long tube but hard to tell. If they dump where the factory Y pipe would then the longer tubes would be their way of making them long tube. You also get them crazy shapes when trying to make all the tubes the same lengths. If the other side had no restrictions then to match this side they had to go crazy. As Jim pointed out headers are made to work in a certain RPM range. Smaller tubes keeps the velocity high ay lower RPM to help pull the gasses out of the motor but not made for higher RPMs. Larger tubes would have lower velocity flow at low RPMs so don't work to good at low RPM but start turning higher RPMs and now you are back up with the velocity to pull the gasses up of the motor. BTW in racing with open headers you want to run header extensions of a certain lengths for RPM range too. Dave ---- BTW Eldy sold headers and shorties at one time, don't know if they still do. I know years ago they stopped making shorties for Jeeps and there was 1 set that fit AMC cars. To get rid of stock they were selling them 50% off. I got a set for my Javelin and hope they fit as I have not tried them, the long tube headers have pin holes and gasket leaks. Link to comment Share on other sites More sharing options...
Rusty_S85 Posted July 31, 2020 Share Posted July 31, 2020 From the look of the picture they would be long tube but hard to tell. If they dump where the factory Y pipe would then the longer tubes would be their way of making them long tube. You also get them crazy shapes when trying to make all the tubes the same lengths. If the other side had no restrictions then to match this side they had to go crazy. As Jim pointed out headers are made to work in a certain RPM range. Smaller tubes keeps the velocity high ay lower RPM to help pull the gasses out of the motor but not made for higher RPMs. Larger tubes would have lower velocity flow at low RPMs so don't work to good at low RPM but start turning higher RPMs and now you are back up with the velocity to pull the gasses up of the motor. BTW in racing with open headers you want to run header extensions of a certain lengths for RPM range too. Dave ---- BTW Eldy sold headers and shorties at one time, don't know if they still do. I know years ago they stopped making shorties for Jeeps and there was 1 set that fit AMC cars. To get rid of stock they were selling them 50% off. I got a set for my Javelin and hope they fit as I have not tried them, the long tube headers have pin holes and gasket leaks. Yep thats what I was going to post but you got to it before I had a chance to post. Just their way of making the tubes equal length. You can go quite insane when it comes to equal length on the headers. Such as this popular old hotrod photo here. As far as rpm range thats right. Shorties are typically street headers good to about 5,500 - 6,000 rpm while long tube headers are more geared for the 6,000 - 7,500 rpm range. But many people have claimed that long tube headers actually build more low end power than shorty headers. I wouldnt know about that, I only picked shorty headers for my 306 build cause I am not turning over 5,500 rpm in my 306 and I figured they would be a step up above stock manifolds but wouldnt be as extreme as full length. Plus the ones I picked also fit very much like OE manifolds which will make life easy for me to get to plugs. Ive seen some horrible headers that you cant even get to the spark plugs with a socket and its like really? Do you really have to squeeze every ounce of power with your design that you cant even get to the plugs Link to comment Share on other sites More sharing options...
Gsmblue Posted August 1, 2020 Author Share Posted August 1, 2020 Yep thats what I was going to post but you got to it before I had a chance to post. Just their way of making the tubes equal length. You can go quite insane when it comes to equal length on the headers. Such as this popular old hotrod photo here. As far as rpm range thats right. Shorties are typically street headers good to about 5,500 - 6,000 rpm while long tube headers are more geared for the 6,000 - 7,500 rpm range. But many people have claimed that long tube headers actually build more low end power than shorty headers. I wouldnt know about that, I only picked shorty headers for my 306 build cause I am not turning over 5,500 rpm in my 306 and I figured they would be a step up above stock manifolds but wouldnt be as extreme as full length. Plus the ones I picked also fit very much like OE manifolds which will make life easy for me to get to plugs. Ive seen some horrible headers that you cant even get to the spark plugs with a socket and its like really? Do you really have to squeeze every ounce of power with your design that you cant even get to the plugs Very interesting! When I get her back I will get better pics.. I drove by the shop today and took this: Should have her back next week! Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted August 1, 2020 Share Posted August 1, 2020 Very interesting! When I get her back I will get better pics.. I drove by the shop today and took this: Should have her back next week! I thought it was Eunice that needed a new tank? I'd start gathering parts for Espy's new heart. GT40 heads, maybe a stroker crank? Link to comment Share on other sites More sharing options...
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