Exhaust On A 351 V8.. Gonna Diy

[someonestolecc]

Hello,

I know it's a skylines forum but there are plenty of on the ball people here and exhaust theory isn't too car specific.

My girlfriend's dad is going to replace his exhaust on his ford. It's a 351 LPG thing and he's already got extractors. Full stainless systems were being quotes over $1000 so he's decided to do it himself.

Does anyone recommend any types of mufflers? I reckon if it's cheap enough it's not worth making your own muffler but better off just whacking one or two in when making your exhaust. The aim is to shut it up without restricting flow too much and still providing a meaty 351 tone.

Anyone got any advice? I'm thinkin something like straight pipe dual system with a couple of hot dogs put in... a bit loud?

[Coupe-This]

how is he making the exhaust ... recomendations would be to not do a H balance pipe but instead use an x pipe configuration. I am in the same boat as you and will be making a full custom stainless twin system for my hz gts.

Pretty simple todo. Ive been told hooker mufflers give a good note and flow well, ive also been told lukey are the only mufflers to go for. Are the mufflers going to be stainless or just steel mufflers. I am going for the hooker mufflers as they are 100 each for 2.5 inlet and outlet and are stainless.

If they turn out to be no good, well i will just get some lukey mufflers and put them on. My exhaust probaly wont be getting done for a month or so though. So i cant tell you results.

Good luck with it tho. Pm me if u want any more specifics that i will be doing/using.

[someonestolecc]

Thanks mate that's a good tip. Where are you getting them from?

Why do you need a balance section?

The system will be a full stainless because of the LPG... (mild will rust cos of the water)

[Coupe-This]

well balance section first of all. In all v configuration engines, one bank (side) always runs hotter and flows more than the other, just creates a more even note. A performance exhaust will have an x pipe in it. Look at all the holden/ford dual systems for there newer cars, they all have H pipes in them. They are just refered to as balance pipes.

Dont go buy one, just get to 45 degree bends, cut them 1/3 of the way in, and weld them together. The best bet with stainless would be to go for grade 316 as it will handle the heat alot better, will cost a little bit more though.

What size mufflers are you after? 2.5 inlet/outlet or ???

www.tuffcarparts.com is where im getting the mufflers from. They are not listed on the website, but send an email and he will give you all the information you need.

[MK2]

Coupe-this has answered most of your Q's but I would recommend that you do a 2.5inch system on it because the lighter density gas exhaust does tend to give some fairly good scavenging effects and the extra mass-velocity when its opened up was worth it, plus you've already got headers on it so thats a good start.

My old 351 in the landau I got converted over to gas in the early 90's and it really isnt that much of a drama as far as corrosion goes but you really have to use good quality oil in them as it burns fairly dry and hot.