964 Engine rebuild
02-18-2014, 04:37 AM
#137
Racer
Thread Starter
Thanks chaps, it will be a slow burner of a project but I am thinking of doing some back to back dyno runs when it is all finished so mapping aside hopefully there will be some factual data!
I thought there must be something more to it - A good friend of mine who has a Moto 3 bike team was showing me their lambda bosses and they are way longer than ours so that the tip of the probe only just protrudes into the tube. It makes perfect sense when you think about it that you don't want it reducing and disrupting the flow of the gasses but that is in a race bike where you are chasing every 0.1hp
Haha, it hasn't been that long!! Do you want me to drop that thing round to Toms sometime so I can take a sneeky peek at his pink project?
Haha, it hasn't been that long!! Do you want me to drop that thing round to Toms sometime so I can take a sneeky peek at his pink project?
Was that TIG? what rig do you use?
02-18-2014, 02:26 PM
#139
Racer
Thread Starter
Me? No no no, I did do some welding in college many years ago but my welding never looked like that - If it was me then it would have been welded and ground back to protect my modesty!!
A friend of mine is doing the TIG welding & he is a superb welder - He made up my oil catch tank, all of the ally ducting at the front of my car and the oil cooler itself (below). I can handle the cutting, machining, fitting & general bludgeoning but leave the welding to him!
The bits that are tacked together are just that but I think that because it's all made from ti I think he said he was going to purge the 'X' pipe so cap the ends off and fill with argon.
A friend of mine is doing the TIG welding & he is a superb welder - He made up my oil catch tank, all of the ally ducting at the front of my car and the oil cooler itself (below). I can handle the cutting, machining, fitting & general bludgeoning but leave the welding to him!
The bits that are tacked together are just that but I think that because it's all made from ti I think he said he was going to purge the 'X' pipe so cap the ends off and fill with argon.
02-18-2014, 03:31 PM
#140
Technical Guru
Rennlist Member
Rennlist Member
I thought there must be something more to it - A good friend of mine who has a Moto 3 bike team was showing me their lambda bosses and they are way longer than ours so that the tip of the probe only just protrudes into the tube. It makes perfect sense when you think about it that you don't want it reducing and disrupting the flow of the gasses but that is in a race bike where you are chasing every 0.1hp
03-08-2014, 04:21 AM
#143
Racer
Thread Starter
1st March car was re-taxed and went to Redtek to have a couple of niggles looked at including swapping the oil tank for one I'd refurbed as the current one had cracked paint and the oil level seal was weeping which is a tank out job so it made sense to tie it all in with a service & get it sorted.
The oil leak was traced to two things: Firstly the RSR rocker seals I initially provided him to fit weren't much cop so oil was getting through and one of the lower magnesium rocker covers was kippered. I knew the rocker cover wasn't great when I first put it back together as it was heavily pitted from corrosion but couldn't find a spare set & didn't want to fork out for billet ones on top of the engine rebuild so powder coated it and crossed my fingers.
The rocker seals were replaced with a set of Nicks own which use an o-ring to seal and as luck would have it I actually had a single billet rocker cover which was the correct one so just stuck that on until I'm feeling brave/rich enough to buy a lower pair.
So the engine looks a bit of a patchwork quilt but suits the outside quite well.
It was so good to get it back, took a nice looong detour on the way back & it felt unbelievably quick after 3 months of VW TDI!
Refurbed tank:
RSR rocker seals:
Redtek rocker seals:
Engine mismatch!
The oil leak was traced to two things: Firstly the RSR rocker seals I initially provided him to fit weren't much cop so oil was getting through and one of the lower magnesium rocker covers was kippered. I knew the rocker cover wasn't great when I first put it back together as it was heavily pitted from corrosion but couldn't find a spare set & didn't want to fork out for billet ones on top of the engine rebuild so powder coated it and crossed my fingers.
The rocker seals were replaced with a set of Nicks own which use an o-ring to seal and as luck would have it I actually had a single billet rocker cover which was the correct one so just stuck that on until I'm feeling brave/rich enough to buy a lower pair.
So the engine looks a bit of a patchwork quilt but suits the outside quite well.
It was so good to get it back, took a nice looong detour on the way back & it felt unbelievably quick after 3 months of VW TDI!
Refurbed tank:
RSR rocker seals:
Redtek rocker seals:
Engine mismatch!
03-11-2014, 10:31 AM
#144
Racer
Thread Starter
I'm thinking of taking a bit of a U-turn on the Corvette silencers. There is still quite a lot of work to do welding up the ends back on as they need a full bead all the way round the ends externally and around the end face which is all time and money (titanium welding rods are $$$).
The other reason is I recently bought a very nice silencer from a 997. The problem with this is that because I want heat I'm going to to stick with the 993 heat exchangers which exit facing towards each other and the 997 silencer is quite wide with the inlets and outlets on the end faces.
Because of this I may have to rob the 'X' pipe I made for the Corvette silencers to make an adaptor pipe a little bit like the Bischoff catalytic converter.
I've sketched up roughly what it will have to look like although I would really like to 'straighten out' some of it. The 993 flanges are at the water cutters so I've got a couple of weeks to figure it out but I also need to get prices for the 180 degree bends as I don't have enough pipe to make this. If they work out at silly money maybe the Corvette boxes and 'X' pipe can go on hold and I'll have to look out for some short headers to go directly into the sides of the silencer and weld a tin round hem for heat.
The other reason is I recently bought a very nice silencer from a 997. The problem with this is that because I want heat I'm going to to stick with the 993 heat exchangers which exit facing towards each other and the 997 silencer is quite wide with the inlets and outlets on the end faces.
Because of this I may have to rob the 'X' pipe I made for the Corvette silencers to make an adaptor pipe a little bit like the Bischoff catalytic converter.
I've sketched up roughly what it will have to look like although I would really like to 'straighten out' some of it. The 993 flanges are at the water cutters so I've got a couple of weeks to figure it out but I also need to get prices for the 180 degree bends as I don't have enough pipe to make this. If they work out at silly money maybe the Corvette boxes and 'X' pipe can go on hold and I'll have to look out for some short headers to go directly into the sides of the silencer and weld a tin round hem for heat.
05-23-2014, 12:03 PM
#145
Racer
Thread Starter
Slow progress but exhaust flanges are watercut and I've been hacking up the old Corvette exhaust so of half the exhaust is now tacked up.
993 heat exchangers are at my welders ready to have the flanges flipped and I did a trial fit of the silencer. All seems to fit so far apart from it being a bit too wide so more bumper also needs to be hacked. Next step is to trial fit it onto an actual engine (instead of my wooden jig) and make a couple of 'J' pipes to link the silencer to the rest.
Hopefully have it done by Christmas.
993 heat exchangers are at my welders ready to have the flanges flipped and I did a trial fit of the silencer. All seems to fit so far apart from it being a bit too wide so more bumper also needs to be hacked. Next step is to trial fit it onto an actual engine (instead of my wooden jig) and make a couple of 'J' pipes to link the silencer to the rest.
Hopefully have it done by Christmas.
09-05-2014, 12:28 AM
#146
Thanks for the adventure! Starting my own soon and will use this thread as a guide...
09-06-2014, 04:48 AM
#147
Racer
Thread Starter
About time I updated this - Exhaust is now up and running. Took twice as long and cost twice as much as expected but it always does right?
I went away from the X pipe design as the LH & RH bank merge inside my silencer anyway + I think I really wanted to use the X because it took me a long time to make and had some very pretty welding on it. It was the only solution when I was going to use the Corvette silencers but maybe it will now make a pretty pen holder for my desk.
First was to finish my cheapie 993 heat exchangers so with the flanges cut off and jig made, they needed rotating,welding back on and linishing flat. The other side needed patching and a new pipe cobbled together. The steel on these is very thin and although stainless, it's not the best grade so can corrode.
Old exhaust system removed:
993 heat exchangers and new rear silencer fitted:
Lots of expensive titanium pipework cut, bent, tacked and welded:
Some lovely welds added:
Lambda bosses welded on:
Fitted
There's always a few bits you think I could have done better and there's still some finishing to do as I may do double slip joints in two places and the tailpipes are just bits of tube at the moment but it's on and sounds good. It's still quite loud although much quieter than the Magnaflow but it now has a real rasp to it and makes a racket on overrun!
With the new exhaust I think the car is now running a bit richer but haven't done enough miles to really get to know it. I'll report back
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