[er455]

Does anyone made a single turbo header kit ? I have a custom kit that I made years ago and i am not sure if it’s efficient enough , my concern is that the drivers side exhaust has to flow into a turbo log and I wonder if it creates to much back pressure ? Also I run a 3.5 downpipe the splits into dual 3” full exhaust pipes is that big enough ?

[R 70 Judge]

Turbo69bird used to make a nice kit for 67-69 firebirds. Not sure if he has any kits left.

Log manifolds should be just fine. Downpipe sizing depends on the horsepower goal whether or not it is a restriction.

I have a set of these on the shelf for when I convert to a single turbo. They are very nice quality
https://www.stainlessheaders.com/i-3...%26go%3DSearch

[charlie66]

Whatever size the A/R outlet is , the pipe should be 1" bigger for the first 18"- 14" . After that you can neck it down from there . You could get away with 1/2" if you have to. If you're crossover pipe is as large as the log i doubt there would be a problem .

I would say that you're fine ...

If you're worried , weld a bung in the pipe and hook the boost gauge to it and you will know for sure ..

[er455]

Thanks Charlie , so my turbo s475 has a 5” outlet should I have 18” of 5” then neck it down ? This is the downpipe we’re talking about .. also what is considered to much back pressure ?

[charlie66]

No problem ...You are in real good shape then .. 1:1 is optimal . But if you have like 1.5 to 1 id say you're fine . Anything more is getting out of range . IMO .....

[charlie66]

I miss read your post sorry. I thought you said that you had a 5" now lol... I think it would be a good idea to have at least 5" for the first pipe right out of the A/R , but if its working ok then id leave it . If it was me id have it at 5" .. If you're pushing the boost pressure over 15 psi it might be a good idea to have a 5" on there though..... IMO

[er455]

Originally Posted by charlie66

I miss read your post sorry. I thought you said that you had a 5" now lol... I think it would be a good idea to have at least 5" for the first pipe right out of the A/R , but if its working ok then id leave it . If it was me id have it at 5" .. If you're pushing the boost pressure over 15 psi it might be a good idea to have a 5" on there though..... IMO

I agree with you I think I need 5” for about a foot then reduce to 4” for a few inches then into my merge pipe which is 3.5 into dual 3”” .. right now it goes from a 5” outlet to 3.5 down pipe , it can’t hurt to go bigger but it makes it hard to get to the plugs with a 5 “ downpipe out of my turbo .. might be possible though , thanks for the advice .

[charlie66]

No problem,

I rolled my pipes up high by the fender on top of the wheel well to keep them away from the engine so i can access my plugs easy .. Maybe you could try that too.

Do you have a picture of what you got going on now?

[er455]

Originally Posted by charlie66

No problem,

I rolled my pipes up high by the fender on top of the wheel well to keep them away from the engine so i can access my plugs easy .. Maybe you could try that too.

Do you have a picture of what you got going on now?

here is a pic of the downpipe with is 3.5 “

[er455]

Sorry for the late response was dealing with a hurricane here in northern Florida 😀

[er455]

Originally Posted by er455

Sorry for the late response was dealing with a hurricane here in northern Florida 😀

Another pic it goes from 3.5” to a 3” y pipe and out the back dual 3””

[charlie66]

Originally Posted by er455

Sorry for the late response was dealing with a hurricane here in northern Florida 😀

Totally understandable, I hope all is well with you.. My brother got hit by that storm . Not fun ...

Yeah looks doable . If i could make a suggestion, i offset my pipe, maybe you could do the same thing to help with keeping the plugs accessible . Ill try to get a picture uploaded to show you what i mean . I dont have a 5" down pipe but i think that you can do it still.

[charlie66]

so if you look i moved the pipe up and over to the fender and also sent it down back from the firewall for more clearance at the firewall. Just something for you to help you decide on how you would like to rout it ..

Good luck

[73 TRANSAM]

I feel that the neck down is so close to the turbo outlet, it will hurt on flow. I have a 5" about 15" then I neck it down to 4" going to the midplate. Then by the tranny it splits to 2 three inch piping. Single turbo is better with a 5" to let it breathe better at higher rpms. I do have a fender exhaust for the track. The street setup sounded very tame so that is a plus.

[er455]

Originally Posted by charlie66

Totally understandable, I hope all is well with you.. My brother got hit by that storm . Not fun ...

Yeah looks doable . If i could make a suggestion, i offset my pipe, maybe you could do the same thing to help with keeping the plugs accessible . Ill try to get a picture uploaded to show you what i mean . I dont have a 5" down pipe but i think that you can do it still.

Yea thanks Charlie we got lucky with the storm it went further north of me , hope your brother faired well … I like how you offset your down pipe I will have to do the same thing ., thanks for the pic .

[charlie66]

Originally Posted by 73 TRANSAM

I feel that the neck down is so close to the turbo outlet, it will hurt on flow. I have a 5" about 15" then I neck it down to 4" going to the midplate. Then by the tranny it splits to 2 three inch piping. Single turbo is better with a 5" to let it breathe better at higher rpms. I do have a fender exhaust for the track. The street setup sounded very tame so that is a plus.

Sup Ed!

Post up a picture of you down pipe give him some ideas for what hes doing . It always helps me to see what others do ...

[charlie66]

Originally Posted by er455

Yea thanks Charlie we got lucky with the storm it went further north of me , hope your brother faired well … I like how you offset your down pipe I will have to do the same thing ., thanks for the pic .

No problem if you need anything else LMK .. All i did was cut a 90 degree elbow into 2 45s dog leged them together to send the pipe over to where i wanted it ..

Yeah he got hit pretty bad . He was worried about his boat , but it wound up being ok . Thanks for the concerns..
Im glad to hear you're ok ....