YEP They are the ones, sorry should have meant 4 into 3 into 1. That is some really nice work there, you got some good welding skills.If your talking about replacing this
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With these
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Then yes it can be none, but for me the best option was to fit them backwards (Left hand on the Right hand side and vise versa) so they exit forwards, this gives far more clearance as they are narrower this way around. The x-right hand, now fitted on the left needs some fabrication to miss the chassis, the x-left hand now fitted on the right clears everything and can be left stock.
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First job was to join the two sides together as closely as possible in as tight space as possible.
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Once that down-pipe and V arrangement was build the rest was easy, complete with Lambda sensor mounts.
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And the rear section, note no rear silencer, this only runs a centre straight through silencer.
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All the mount brackets were also made from stainless steel, and mig'd together using stainless steel wire.
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So from underneath at the front and it a bit hard to take a meaningful picture but this is it all attached.
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And from the back looking forward.
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Yeah I can see from the pics its a better fit. That will be my route definitely. On the off chance, did you plan the pipe work and record the Specs ?Performance wise I can't feel any difference, but it sounds nice now, and there are plenty of those manifolds about for future replacements if required. It probably has made a difference to the performance, but with a 3.9 V8 in a series Landy there's enough power without modifications like this. Fitting these manifolds backwards actually uses less space than the original cast iron items, I'd recommend going this route.
Cheers for the info Murtle have a great dayI had no plan when I built mine, just bought the manifolds and some 2" 304 stainless steel pipe with 1.5mm wall and 180° 2" 304 stainless steel mandrel bends, plus a 15" straight through silencer. In stead of trying to work out what angles of bend you need to buy, just get 180° bends and cut the angles you need from them, one 180° will provide plenty of bends when cut up. If I was doing it again I'd use 2.5" or 3" from the Y-piece onwards, just for the noise.
Welding it all together is easy with stainless steel wire in the mig, and just a small tack when you hold the pipe in place is enough to keep things located while you plan next part of the system. I started at the manifolds and worked backwards addressing each challenge as it came up.