Manifold Facing

Yeowch, rather you than me!

Just popped in to see Newton Motors people, took me a while to find it! =A330 so jobs a goodun - rather go with a known quantity than get a second hand one for a little more and not know if it will crack - at least i know this one shouldnt go too much farther. Thanks for the tip

- he really seems to know what he is talking about, which is a rare thing these days ive found!

Accompanied by the sound of a chisel on slate CoyoteBoy, managed to produce the following words of wisdom

No problem, I'm opening a garage in the next few weeks and we'll be doing all those silly jobs that no-one else wants to do so keep an eye on 'ere and I'm sure I'll accidentally spam it sometime soon.

Brave of you, you'll have to let me know where and when and I'll pop in to say hi!

The message from "Pete M" contains these words:

Best of luck. Trouble with itty-bitty jobs is they cost a lot to do.

Yeowch, rather you than me!

Just popped in to see Newton Motors people, took me a while to find it! £30 so jobs a goodun - rather go with a known quantity than get a second hand one for a little more and not know if it will crack - at least i know this one shouldnt go too much farther. Thanks for the tip

- he really seems to know what he is talking about, which is a rare thing these days ive found!

The last manifold I machined was for a Toyota GT4. As a precaution against it warping again, I had it stress relieved first. I can't help feeling that such distortion is probably due to manufacturers using 'green' castings. Mike.

bearing in mind it is thrashed fairly often so spends most of its time glowing, I'd say it was fairly close to being relieved in the process of use lol. I discussed it with the guy machining it and he agreed - it was miles out. The problem with the GT4 manifold is that its a solid, deep block- not seperate runners and a flange. The only one ive seen similar to this was a marine BMW straight 6 engine (same as the old 3.5 car engine but with a GT4-style manifold with added water jacket) - this had similar issues. I think the extra meat all together means theres greater propensity to gather stresses in the cooling phase - ideally they should be relieved at the factory before machining, but that costs money lol.

Anyway, cracking of them is fairly common, as is warpage, so we'll see how this lasts. I dont actually have the cash to re-insure or tax it at the moment so its going to sit on the drive after then.

Yep. You're probably right. The chances are that most of the stresses have gone now, so as long as it is not cracked already, remachining should make it better than new. :-) 'Proper' stress relieving though is quite a controlled process. Basically soaking at high temperature, followed by a controlled slow cooling cycle.

I discussed it with the guy machining it and he agreed -

IIRC many older inlet and exhaust manifolds were 'solid' in that way. I'm talking 30 plus years ago BTW.

The only one ive

I assume we're talking about the 3S-GTE engine. A good engine, but with one or two weaknesses, like the exhaust manifold problem. Another is that the turbos tend to come loose. On the engine I worked on, I made stainless steel studs, and drilled the nuts, so they could be wired. AFAIK they haven't come loose since. :-)

IIRC though, later engines had an extra support for the manifold, with a modified flange for the turbo. Mike.

Yup.

Beyond the early 80s is beyond me ;), ive only really worked on newer ones.

Indeed, this is a second get 3s-gte, Ive had one manifold crack already and yes the nuts come loose fairly often.

We are of like mind, I started by replacing the downpipe studs with stainless bolts in order to make removing the dp easier and prevent corrosion, used stainless spring washers (didnt expect them to last but they have). I've never had problems with the mani-to-turbo or manifold nuts myself but other seem to regularly.

The 3rd gen is identical to the 2nd in support and flangery, the 2nd gen has two types of manifold, 7 and 9 stud - the 9 was carried forward onto the 3rd. The intake side of the 3rd is totally different to the second, no longer using the TVIS dual runners and hence making lower torque figures but higher power, higher up the range. Also the

Love this engine, it might cause me lots of aggro but i still love it! Especially now its megasquirted - it really releases the beast.

Getting a bit cheesed off now. First they told me it would be ready for Thursday, so I drove the 40 mile return trip to get it (without phoning, stupid me I admit) and they said they hadn't even looked at it - so I canceled my MOT and re-arranged for this weekend. They said they'd give me a call when it was ready and I've not heard from them since. Will be calling tomorrow to chase them up but I need the car moving - its really not a big task, i didn't think it would take them over a week to do!