I bought a cheap eBay manifold (Speed Daddy), but the collector flange is pretty thin. The flanges are also mild steel instead of stainless. I've heard that if you wrap and weld more metal onto these manifolds, they won't crack. Anyone have experience with this?

I'm not sure if I want to invest in cash in something that will still break. I ran across this manifold which I would would have bought already but they're in New Zealand.

http://www.hybridperformance.co.nz/hp/p ... product=91

Does anyone know anything about these guys? It looks pretty sturdy.

I'll be running an Aliexpress/Ebay special manifold this season. It's been braced in multiple places and that does seem to help a great deal. Flex section in the downpipe is a big one too.

Really though it seems like everything cracks sooner or later. Even Full-race pieces eventually give up the ghost I hear.

The manifold you linked is absolutely terrible though. The angles runners 2-3 make where they are welded to the flange actually kinda piss me off. They compromised exhaust flow so they could put the flange where it is without having to cut and weld a more complex bend. You're never going to be able to balance the A/F ratios across all cylinders and the middle two are going to have different timing requirements than the outer two because the flow rate and mixture quality in each cylinder will be so drastically different.

I ran an ebay one with my PT61. I did brace it up substantially and re-welded everything and never had any issues.

Thanks for the feedback. I really appreciate it. If anyone knows where to get a quality manifold, please let me know. All I can find are these Chinese ones and that one I linked.

The one I have is from Speed Daddy. Their manifolds for other engines are OK, but I don't know how they work for CAs. Testing different parts with a magnet the flanges are mild steel and half of the runners are. I put blue lines on the mild steel parts and yellow on the stainless to show what I'm talking about.





Ignore the white paint.

I don't care if the whole thing is mild steel, I just don't want it to be strong. I plan on bracing it from the head to the turbo and downpipe. My understanding is that if you brace it straight to the flange it will crack.

Any ideas are welcome.

Mean Green, he's alive!!!! Where ya been dood?

The way I did it was I braced the turbo flange with 1/2" rod to the head flange. I did the same with my RB20 and SR20 maniflolds over the years and never had an issue with any of them.

Similar to this

Most of your cracking will be caused by the weight of the turbo and exhaust hanging on the runners. If you support it flange to flange like this, it will give it some support and help take the excessive weight off the manifold runners when it heats and cools.

I also ran solid mounts on everything. Engine, trans, exhaust etc. Everything was rigid and couldn't flex around too much if any. It causes some vibration through the car, but seemed to help over my SR car that use to crack the downpipe often.

Thanks! That's exactly what I was looking for.

Looks like I just weld a couple of rods for support like in the picture and see what happens. Now I have to build a new down pipe, which is a pain with the tight space I have to work with.

float_6969 wrote:Mean Green, he's alive!!!! Where ya been dood?

I'm alive!!! Haha! I'm here, just been extremely busy between work and working in the shop. I still get on here often, just haven't been as active in the last couple years.

dhen wrote:Thanks! That's exactly what I was looking for.

Looks like I just weld a couple of rods for support like in the picture and see what happens. Now I have to build a new down pipe, which is a pain with the tight space I have to work with.

Yeah man, it worked great for me. I had a good friend re-tig the entire manifold and I also planed the flanges to ensure the surfaces were true. All in all, I had about $400 into the manifold when done, but still cheaper than some of the big name manifolds at the time I did it.

im going to type this once.

the ebay manifold hold up great if you drive ur car evey once and a while. if you daily drive your car, then expect it to crack sooner than later. no matter how much bracing it comes with.
i have gone thru two top mounts. and i have tried to brace and have them fixed many times.. but not cigars. they continued to crack. and on top of that, not all the flanges were strait. ask you local machine shop how much they charge to straighen a flange? around here its 80 an hour. all the money that i put into those manifolds, i would have been better off just having a professional one made. which is what i did. i had it made of sch80 mild steam pipe with half inch thick flanges all the way arround. and never had a problem since. also if you have it made professionally made, all surfaces will be straight.

b210boostpimp wrote:im going to type this once.

the ebay manifold hold up great if you drive ur car evey once and a while. if you daily drive your car, then expect it to crack sooner than later. no matter how much bracing it comes with.
i have gone thru two top mounts. and i have tried to brace and have them fixed many times.. but not cigars. they continued to crack. and on top of that, not all the flanges were strait. ask you local machine shop how much they charge to straighen a flange? around here its 80 an hour. all the money that i put into those manifolds, i would have been better off just having a professional one made. which is what i did. i had it made of sch80 mild steam pipe with half inch thick flanges all the way arround. and never had a problem since. also if you have it made professionally made, all surfaces will be straight.

As stated above, if done right you will have no issues. I've had KA-T, RB20, SR20 and CA18, all of which had eBay manifolds. I had them all planed, braced and re-welded as I posted above and never had any issues and trust me when I say, I never took it easy on my cars lol

from reading on the net, the earlier ones were real problematic, then they seem to improve ?

daily driven ca18det powered b210 sounds hella cool. Any project page, links, etc. ?

dash wrote:from reading on the net, the earlier ones were real problematic, then they seem to improve ?

daily driven ca18det powered b210 sounds hella cool. Any project page, links, etc. ?

+2

Here's my ghetto manifold bracing. Do you guys think I should cut one of the braces? I've heard that bracing it too much can make the manifold crack because it needs to expand when it gets hot.

dhen wrote:Here's my ghetto manifold bracing. Do you guys think I should cut one of the braces? I've heard that bracing it too much can make the manifold crack because it needs to expand when it gets hot.

I would cut both off and brace from both corners of the turbo flange on about a 20º outward angle to the manifold flange. Heat is not what cracks the manifold, the cooling and sagging/flexing due to the weight of the turbo and exhaust hanging on the manifold is what does it. The manifolds usually crack on the top. Supporting that so it doesn't sag as easily is how you prevent it in my experience.

What MeanGreen said, sort of.

We typically brace them from underneath either to the block or to a motor mount, that way the brace is at a nearly vertical orientation and transmits any force from the weight of the turbo straight through the brace with reduced flexing.

Buddyworm wrote:What MeanGreen said, sort of.

We typically brace them from underneath either to the block or to a motor mount, that way the brace is at a nearly vertical orientation and transmits any force from the weight of the turbo straight through the brace with reduced flexing.

That way works just as well, I just prefer to have the braces up top and out of the way or at least where they are easier to figure out how to get around if you need to take things off lol! I never had a failure on any manifold done that way. Having long braces going down from the bottom can create clearance issues when working on the car not to mention the manifold heats and cools as one my way, the braces being attached to other parts of the car that don't see extreme heat may cause it to flex in other ways. Believe it or not, when you dump the clutch from a dig, that motor mount bracket does flex.

I have yet to blow out a manifold due to motor mount flex! lol

Fingers crossed.

lol I'm honestly shocked I never had an issue. I did mine the way I did on a whim... It worked so I never did any different lol

a metal motor mount bracket flexes...... bolted to a rubber mount ? And how do u get to c it 'flex'.... video ?

I've put gopros all over my cars. Suspension, under hood in different areas, rear end etc. You would be surprised what you can see and learn from that lol I've owned and built 6 of these cars over the years from the ground up from SRs KAs, RB's and CA. . There isn't much I have not seen at this point good or bad. Yes, even bolted to a rubber mount, that metal bracket flexes. If you do not believe it does, you are a fool. That rubber only moves so far and then something else takes the brunt. It doesn't flex huge amounts, but a little bit is all it takes, even just 1mm. Nothing is ever perfectly rigid, it will all flex at some point. The reasoning behind what I said is you are bracing it to something (the mount) that is not heating and cooling at the same rate as the manifold. The block flexes, the mount flexes, the chassis flexes, the manifold flexes. They all move around different from each other at different rates and for different reasons under load and driving conditions. I always brace to like surfaces.

alot of us "fools" wont believe that 'flexing' crap.... no matter where u stick you go pro -lol
what i did see on all three of my ca18s is that rubber mount completely torn away
lotsa factory cars brace their manifolds (turbo and na) to that motor mount bracket
Whatever works for us dummys, eh

ca18 stock mani leaves aalllottt of room around the head studs. Biggest I've seen on any motor

Everything flexes, as you said MeanGreen. The head shakes around separately from the block at high revs even. Question is to what degree, as you also said. I'm not convinced we've got the data to really sort out better from best.

A manifold braced with horizontal braces between head and turbo flange *might* heat at the same rate assuming the alloys are similar, for instance. But either way we're still dealing with numerous unknowns, such as the rate of expansion of those horizontal braces. They're going to get longer and push the turbo flange away from the head, but how much? More than the degree to which a metal bracket flexes? I can't say for sure but I suspect a gopro video is not sufficient evidence either way.

I do know that when you plumb wastegate dumps back into the downpipe you should ideally be using a flex joint specifically to deal with heat expansion/cycling. But that's as far as we're going to get here I think, unless we want to wind up splitting hairs on who's making the best unquantifiable compromise in this thread! lol

The message I take away from talking with our engine builder here is that isolating the manifold from twisting and flexing forces in as many axes as possible is the main consideration while also supporting the weight of the turbo.

dash wrote:alot of us "fools" wont believe that 'flexing' crap.... no matter where u stick you go pro -lol
what i did see on all three of my ca18s is that rubber mount completely torn away
lotsa factory cars brace their manifolds (turbo and na) to that motor mount bracket
Whatever works for us dummys, eh

ca18 stock mani leaves aalllottt of room around the head studs. Biggest I've seen on any motor

dash, you are a fool for believing what you believe because obviously you are the only one. Congratulations. Your logic is absolutely flawed trying to compare stock bracing on a stock manifold to an aftermarket piece. Stock manifolds are far sturdier than an aftermarket ebay piece. There is zero comparison.

I'm not some dumb kid. You might want to think twice when you start being a snide little punk. My experience spans over 10 years with S chassis cars alone not to mention working for Rolex Grand Am series race teams as well as building and driving my own racecars for the past 15 years in various different forms of racing. I'm trying to help teach something and you want to run your mouth, I'll shut you down every time.

Buddyworm wrote:Everything flexes, as you said MeanGreen. The head shakes around separately from the block at high revs even. Question is to what degree, as you also said. I'm not convinced we've got the data to really sort out better from best.

A manifold braced with horizontal braces between head and turbo flange *might* heat at the same rate assuming the alloys are similar, for instance. But either way we're still dealing with numerous unknowns, such as the rate of expansion of those horizontal braces. They're going to get longer and push the turbo flange away from the head, but how much? More than the degree to which a metal bracket flexes? I can't say for sure but I suspect a gopro video is not sufficient evidence either way.

I do know that when you plumb wastegate dumps back into the downpipe you should ideally be using a flex joint specifically to deal with heat expansion/cycling. But that's as far as we're going to get here I think, unless we want to wind up splitting hairs on who's making the best unquantifiable compromise in this thread! lol

The message I take away from talking with our engine builder here is that isolating the manifold from twisting and flexing forces in as many axes as possible is the main consideration while also supporting the weight of the turbo.

Absolutely, everything flexes and heats/cools at different rates and yes, to what degree is the real point. I wasn't exactly suggesting placing the go pro will physically show this, sorry if it came across that way that would be my mistake for not being clearer, but as I said you would be surprised what you can learn from placing one in your engine bay in different places as well as under the chassis at suspension points etc. Anyway, the thicker material of the 1/4" solid steel rod used for bracing will heat and cool at a different rate than the manifold, that is correct, however the thicker steel also heats slower and cools slower than the thinner manifold runners. I always match bracing rod size to the flange thicknesses. They will generally have a similar heat/cool rate. The thicker material will also have less give than the thinner metal used on the runners. When a manifold cracks, it generally cracks at the point of most hanging pressure which is at the head-to-manifold flange and the elbows in the runners on the top of the welds. This is my reasoning for bracing it the way I do because I always felt bracing it to itself made much more sense than trying to find something else to brace it to. Longer braces have a tendency to flex also. I'm not saying other methods are wrong, I just strongly feel my way is the simplest and most efficient. As I said, I have never had one fail.

nope I'm not the only one who saying a gopro won't show you that deflection.

to what degree is the real point. I wasn't exactly suggesting placing the go pro will physically show this, sorry if it came across that way that would be my mistake for not being clearer

Thats exactly what it came accross as, and dash was calling bulsheet on it.

Stock manifolds are far sturdier than an aftermarket ebay piece. There is zero comparison.

and they are alot heavier too. We also ARE talking about supporting the weight of the turbo + mani(+downipie). Of ourse there is comparison. Fool

dash wrote:nope I'm not the only one who saying a gopro won't show you that deflection.

to what degree is the real point. I wasn't exactly suggesting placing the go pro will physically show this, sorry if it came across that way that would be my mistake for not being clearer

Thats exactly what it came accross as, and dash was calling bulsheet on it.

Stock manifolds are far sturdier than an aftermarket ebay piece. There is zero comparison.

and they are alot heavier too. We also ARE talking about supporting the weight of the turbo + mani(+downipie). Of ourse there is comparison. Fool

An OEM cast manifold is thicker, sturdier and engineered for the stress put on it by the weight of those tiny little snails that come from the factory. The weight of a top mounted T3/T4 or like I had, a Precision SC61 60 trim, is far greater than that of the stock T25 or whatever was on these engines... I just throw those things in the trash. These ebay brand turbo manifolds are thrown together half assed and the only engineering in them is the s*** they engineer when they write the descriptions on the websites posting them for sale. The aftermarket manifolds flex substantially more than a factory cast manifold period end of discussion. You can not compare a stock cast manifold to an aftermarket tubular manifold in any way whatsoever. They are absolutely 100% different.

I personally have tested the ebay T3/T4 top mount manifold as well as a chinese GT35R turbocharger and the results were not good. The chinese GT35R lasted about 6,000 miles and the thrust washer failed, but didn't smoke. The impeller would just stop turning under load which means it wouldn't produce hot air under load. The manifold started cracking, so I braced it. The manifold kept cracking until it completed seperated my turbocharger from the maniold itself. I still have that manifold if you guys want to see pics. Just disgusting. Just have someone make you a manifold of the s*** steam pipe and call it a day. That stuff does not buck or bend for anything.

boost_boy wrote:I personally have tested the ebay T3/T4 top mount manifold as well as a chinese GT35R turbocharger and the results were not good. The chinese GT35R lasted about 6,000 miles and the thrust washer failed, but didn't smoke. The impeller would just stop turning under load which means it wouldn't produce hot air under load. The manifold started cracking, so I braced it. The manifold kept cracking until it completed seperated my turbocharger from the maniold itself. I still have that manifold if you guys want to see pics. Just disgusting. Just have someone make you a manifold of the s*** steam pipe and call it a day. That stuff does not buck or bend for anything.

Those ebay turbos have junk parts in them. They are cheap for a reason. I used one on my SR, but had it rebuilt and it was pretty good. When the turbo shop took it apart he said the shaft was not even balanced properly which is likely what causes the failures in those turbos. You get what you pay for... I refuse to use anything but the best anymore even if it takes a little longer to come up with the money for it. The piece of mind in the end is worth it.

Let's all play nice, OK? They put me in here to moderate because nothing ever happens, don't make me lose my job, LOL!!!

lol