Dyno Don's Y-pipe
 

My new Dyno Don's Y-pipe just arrived. What a beautiful piece of craftsmanship. I wish I had his headers. For now, I'll be mating this well made 2.5" pipe set to my SLP 1 3/4" headers. I got his dual cat pipe set to fit my new 2.5" dual exhaust, which I should be ready to start building in a few weeks. It will take some time to build, since I will take the time to make it as close to perfect as possible. I plan to take photos and post a thread on the project.

For now, THANK YOU DYNO DON!!!

Re: Dyno Don's Y-pipe
 

How much was it? Pictures?

-- Joe

Re: Dyno Don's Y-pipe
 

I bought it through Top Down Solutions for $260. Don offered to sell direct for less, but I had already placed the order. The part was done and shipped way quicker than I expected too. I know I could have built my own for less, but it wouldn't look this clean and clean is key on this project. Don says that I'll have to make small mods to fit my SLPs. I'll check that out when I have the car here tomorrow. Its first real trip out of the garage since last fall YAY!

A photo of the pipe set is here: http://www.top-downsolutions.com/pow...no-don-headers

I will take photos, as I build the new fuel and exhaust systems. I usually get too focused on the job and don't stop for photos, but I promise this time I'll do better. My Classic Chambered mufflers are ordered and on their way. I'll buy the pipe in a week or two and be ready to start work. The fuel system will be first. That will take one long weekend. I expect the exhaust to take several weekends. I'm going to make a temporary y-pipe and muffler, using my current y-pipe and one of the CC powersticks, that I can quickly bolt in to drive the car to and from the shop while I build the exhaust. The temp should sound pretty wild, lol.

Re: Dyno Don's Y-pipe
 

I took a minute the other day and test fit the y-pipe to the car. It actually doesn't look like I'll need to do much fab work on it to make it fit the SLP headers. I will need to redo my trans cooler lines. I replaced the 5/16 OE lines with 3/8 when I built the trans 2 years ago. One of the lines dips down a little and will interfere with the new pipe. No problem, I didn't really like how the lines turned out anyway and this gives me another reason to redo them.

A box full of mandrel bent 2.5" pipe just arrived from Summit Racing. Now I have all the materials for my exhaust system. Just about out of excuses for procrastinating on the project. I do still have my friend's dragster to finish, then I'll have my weekends free and I'll get going on my car. In the meantime I'm just enjoying driving it.

Re: Dyno Don's Y-pipe
 

ill sell you my dyno don headers, going turbo ls

Re: Dyno Don's Y-pipe
 

Did you ever sell them? and do you have the Y pipe too?

Re: Dyno Don's Y-pipe
 

I have made solid plans for building my new fuel system over Memorial Day weekend. Once the fuel system is done, I'll start work on the exhaust, which may span over several weekends. The goal is perfection, or as close as I can get to it. Time is a secondary issue. I do plan to take plenty of pictures of both jobs.

I'm correcting flaws from my original build 15 years ago. Exhaust and fuel system are two big ones. A few more things to resolve, then I'll put funds together for the new motor. I may do a 383 from my existing 355 for the short term while I save for the Dart block to build the 406.

Re: Dyno Don's Y-pipe
 

Okay, so I tried my hand at some exhaust welding this weekend..........

I've used my new Eastwood 175 MIG a few times since I got it, just getting a feel for it. It is a great welder for the price. A bit sorry I didn't save a few extra dollars and buy American, but at least for a Chinesium unit, it is well engineered and works as well as the best welders I've used. That being said, I am as out of practice as ever. I'm a bit embarrassed to think that the exhaust I put together for my buddy's 70 Camaro sportsman is going to be looked over by tech inspectors. I mean, I know I had the settings right and parts of the welds, where I was able to see what I was doing, actually look very good. The problem I was having was seeing to weld. I kept running off track and having to go back and re-weld portions where I missed the joint completely.

I bought an auto darkening large view helmet with the welder and it seems to work great but I am having a really hard time seeing through it. I used an extra lamp to try to light the weld area better, that helped some. I adjusted the shade level all the way down. That also helped some. I may also replace the screen protector and see if that doesn't clear things up some. I think my fuel system and exhaust system plans will turn out great, if I just don't screw things up with crappy welding.

I think I'll stay late a few days this week and practice up some more, see if I can't get the helmet and lighting set up better. I'm a little nervous now since the next welding project I have coming is my fuel tank sump. I've got to do better on that.

Re: Dyno Don's Y-pipe
 

Got the fuel system change done over the holiday weekend. You can read about it and see photos over on the Tech/General Engine forum. I may go back and make some changes to my tank sump, it hangs lower to the ground than I intended. However, the big part of it is done and I'm about ready to start on the new exhaust system. Since I removed the old exhaust to do the fuel tank job, I connected one of the Classic Chambered Powersticks to the cut off 3" just behind the existing SLP y-pipe. This is was meant to get me by as a temporary exhaust while I work on the dual 2.5"

It is so friggin loud. I drove it home and I won't drive it again, except back to the shop to fix it. I am going to buy two cheap glass packs to use instead for a temporary exhaust. I'll save the powersticks for the new system. They'll sound alot better as part of the complete system.

Re: Dyno Don's Y-pipe
 

Today I ordered two of the cheapest 2.5" glasspacks that Summit Racing sells. I'll install Dyno Don's collector pipes(not really a y-pipe) and attach the glasspacks temporarily for trips between home and the shop while I fabricate the complete exhaust system over the next several weekends. I'm still working out the dimensions for the termination box. I think my initial plan will work. I just need to fine tune the shape and size to fit the space. I'll post photos as the work begins.

Re: Dyno Don's Y-pipe
 

Okay, I don't know if anyone is following this thread. So far I've just been rambling on about my plan and my failed attempt at a temporary exhaust. Today however, I have real progress to report with photos to share. So, without further delay........ This weekend, I took the opportunity to revise the fuel tank sump that I built over Memorial Day weekend. I also put together a plan for a better temporary exhaust. Something that would sound good enough to let me drive the car while I work on the permanent dual exhaust system and also be quick to remove/install for days when I work on the exhaust.

For this plan to work, I had to get the Y-pipe installed first. I was a little nervous since this meant fabricating a new bend on the driver's side pipe, as per Don's warning that his headers are different from the SLPs that I have. I was so pleased with how well this went. Yesterday was an exciting and very productive day for me. It's now a quarter to 11 Sunday morning. I've already had the car out for a road test, cleaned up the shop and I'm sitting at my computer. That is better than I expected the weekend to go. Having this part of the project go as smoothly and turn out as well as it did gives me alot of encouragement to continue towards completion of my dual exhaust.

As you view my photos, remember the welds you see are not Dyno Don's. His welds are very nicely done, obviously TIG welds. Mine are the best I could do with my MIG welder. The welder is very nice and capable of perfect welds. I have to hand it to Eastwood. For a cheap Chinese welder, their MIG 175 welds as well as any welder I've ever used. The limitation here is my lack of skill and practice. Having said that, I gotta say, at least some of my welds turned out pretty good. Even the not so awesome ones have good penetration and should be plenty strong.

The best part of it all is how well the bend at the driver's header turned out. I cut up a mandrel 90 from my Summit dual exhaust kit and eyeball fit the pieces. It really turned out great. The fit is almost perfect and the three joints I ended up with aligned really well. At one point I thought I'd be scrapping the piece I had cut and grabbing another 90 to try again, but with a little adjustment, things went right together.

The temporary part of the system is the glasspacks. They are attached with weld on tabs. I totally pirated this concept from Willie, who posted a thread on his very nice dual exhaust system in the dual exhaust picture collection.

The tabs make it so the mufflers come off with three bolts in about 5 minutes. This will allow me to pull them real quick and easy on days when I work on the permanent exhaust system. The whole exhaust will be designed as much as possible for quick remove/install for ease of under-car service.

Re: Dyno Don's Y-pipe
 

Here are the photos I promised. Having a hard time uploading them.

Re: Dyno Don's Y-pipe
 

I'm glad I went bad and read everything, because after just looking at the pictures, I thought; "That's gonna be REAL loud". Looks good for a temp job. And it will work for exactly what you planned it to.

Re: Dyno Don's Y-pipe
 

So is that a SLP Y pipe sitting on the trashcan?

Re: Dyno Don's Y-pipe
 

Looks like one.

-- Joe

Re: Dyno Don's Y-pipe
 

Oh yeah. 2.25" into single 3", with one of my Classic Chambered 3" by 26" Powersticks clamped onto it. That sounded race car cool for sure. Couldn't hear myself think above 2,000rpm. Sad part is that I guess the SLP dual cat pipes were 2.5". I could have gone that route when I bought their headers back in 99. Bad call on my part. The problem is solved now though, thanks to Dyno Don.

I forgot to mention, the motor seems to like the added capacity of the 2.5" secondary pipes. No dyno to know for sure but it feels like maybe 15-20 ft lbs freed up at 4K. It should really make a difference with the Pro Flow intake installed.

Re: Dyno Don's Y-pipe
 

I have 3 SLP dual cat Y pipes and I have yet to see a 2.5 Y pipe from them. (Other than the 1 preproduction 2.5 inch setup and it was a full on dual 2.5 inch setup all the way out the back)

Re: Dyno Don's Y-pipe
 

I would love to see the full dual 2.5" exhaust from SLP. I bet it was a very nice piece. Too bad they dropped support of the 3rd gen. I got the idea that their dual cat Y-pipe was 2.5 from Willie's dual exhaust thread. I thought he said that he had the SLP dual cat unit and it was 2.5". Maybe I misunderstood. At any rate, Dyno Don's Y-pipe may not be stainless but it came together nice. It is aluminized and I painted it up with high temp so it should last a while. The 3" cat back from Edelbrock that I installed 15 years ago is still in pretty good shape(only 35K miles since then). It's aluminized also. In fact, I'm going to cut off and reuse the 2.5" tail pipes in the new system.


Have you seen the Black Beard system? I'm having an old guy moment and can't remember who makes it. There is a thread here somewhere that mentions it. It's part of an LS swap header kit, but the stainless pipes themselves, that run the stock exhaust route, could certainly be adapted to any header package. They are pricey though.

Re: Dyno Don's Y-pipe
 

More photos that got missed in my earlier update. I'm real proud of how that LH end turned out. Could have just as easily been a mess. I hated cutting into Don's work. Having it turn out well made it all worthwhile.

Re: Dyno Don's Y-pipe
 

I revisited the fuel tank sump today to tuck the pump inlet line and filter up in front of the pump, rather than hanging down behind and below. I'm much happier with it now. If you want to see photos, look for my thread on the Tech/General Engine forum. I want to be sure the fuel system is all good before I reinstall the heat shields and finish the exhaust.

In the meantime, I have a guilty confession to make. I'm kinda starting to like the dual glass packs. I know they are loud and unrefined, I have to turn my 1500 watt Alpine amps all the way up to hear the music over the exhaust. But damn does it ever bring out the true character of this engine. It's like driving a big block 68 Chevelle with Cherry bombs and dumps under the car.

The Flowmaster 80 series with single 3" really masked this engine's exhaust tone. Now, it is very obvious what's going on under the hood. And I'm kinda likin it in a juvenile delinquent kind of way. The power difference with the engine now able to breath is substantial. I hear kids everyday tell me how the 4" tail pipe tip makes their stock Honda Accord run like a race car. But seriously, the difference in throttle response in this car is impressive. I will finish the exhaust system and using a termination box ,installed where the glass packs start, the complete system should perform every bit as well as the short pipes do now. I hope the full system sounds as good as this temp system does, if hopefully a little quieter and with less interior resonance. I'm pretty sure that alot of the resonance is due to the pipes ending right under me.

Re: Dyno Don's Y-pipe
 

Just a quick update. I haven't made any progress on the exhaust since I installed the temporary glass packs. My buddies all say they love the car's new sound. Myself, I'm getting tired of having to crank my 1,500 watt stereo all the way up to hear it over the exhaust on the highway. Meanwhile, I've been busy trying to finish the 70 camaro project with my friend and taking care of my kids' cars.

I am nervous for some reason with building the termination box. I realize how tight clearances are going to be and I want it to be perfect. I can see how it should be done, I just need to put pencil to paper, measure, and lay it out. Then start cutting and welding sheet metal and pipe to build it.

One advantage to the delay is that I've gotten a chance to see where problems might arise. I already see the pipes sagging a little right in the area where the termination box will start and where the temporary glass packs attach now. I was concerned this might happen with a slip joint at that point instead of solid welds. My plan was to have the termination box slip fit onto the collector pipes for quick removal should I want to modify it in the future. Now, I'm thinking I may need to weld it up solid to prevent the pipes sagging. Haven't rubbed the pipes on anything yet but They are down 1/2" from where I put them to start with. I'll install new donuts and reset the pipes before I proceed with the termination box. I may also install a hanger at the point where the termination box starts for added support, but I'm not sure yet if that's the way to go.

I've been focusing on putting together parts for my new intake. I ordered the Edelbrock Pro Flow XT on Friday. I'll try to put together the remainder of the needed parts for the install over the next few months. I know I'm kind of jumping ahead since I haven't finished the exhaust yet. But at least I have all the materials for the exhaust. The only thing really holding me up is my procrastination. I'll get tired enough of the loud exhaust and get the damn thing done soon, I promise. Of course, I'll post photos of the project as I go.

Re: Dyno Don's Y-pipe
 

I just installed a set and it didnt fit well. The oil pan was a stock replacement by summit i think...but looked pretty close to same as oem so not sure if that was the problem but the driver side piece didnt line up and hit pan. I had to shorten the length of the pipe under the pan 1/2", and then add extension of 1.25" roughly to the ball socket flange area.

Other than that it was nice

Re: Dyno Don's Y-pipe
 

Thanks Orr for your reply. You can see from the photos of my install, what mods I had to make to the driver's side pipe. They included adding some length below the ball flange. I was lucky that it turned out as well as it did. Don said the driver's side would require modification to fit the SLP headers since the driver's side was different.

Most of the AM pans that I've used had a little different shape in the front area where the pipe goes across. At least the Milodon and Moroso stock capacity pans have more of a slant at that point. It can cause issues on some early Chevys with steering linkage interference. I found plenty of clearance for the driver's side pipe in that area with the stock pan.

I ran into a roadblock to continuing towards my Pro Flow XT intake swap. I just finally redid my fuel system two months ago, reusing the Aeromotive A750 that was part of my old system. This pump had a rough life getting overheated a few times to the point it shut down. It also got fuel starved more than once. This morning, it died on me. Didn't even get out of the garage, good thing I guess. My power supply and grounding of the pump are rock solid and the fuse didn't blow. I'm quite sure it's just the pump saying goodbye. I'll test tonight with my labscope and low amp probe to be sure.
Had to call Summit and cancel the Pro Flow in exchange for a pump. I went with the Fuel Labs 40401. It looks like a great design, brushless motor and variable speed. 75gph at 45psi. Plenty of pump for my future power goals.

Hopefully, I'll get back on track with the intake next month.

EDIT: After conversations with the guys at Fuel Lab and some more calculations, I decided to go with the larger 41401 pump instead. I can run it on constant low speed and it will meet all my future fuel needs.