Aahso, thanks girz. I have not actually seen one. In my view, the "flat" guy looks okay.

Psyber: Das ist nicht was Ich haben .... meant no jab, but tested many manifolds.

The cast manifold winds up kinda locked in and resists mods. It's also heavy. The fabed manifolds float off into space if not anchored. Castings are the cheapest to make, not counting the pattern work. Patterns are fun to make save an allergy to sawdust.

I like castings, provided one can get inside the things and clean them up. Several other problems exist that I'd like to solve. The throttle position winds up in a clumsey spot and does not inherently contribute to an easy uniform distribution. Better locations all look a bit odd.

Regardless, I'm in the middle of trying to figure it out with thoughts of a new casting. Suggestions are welcome, and I'll consider anything.

corky

Glad this thread is fairly recent, I've had a couple of problems with my manifold but no one else has started a thread discussing the same problems as me.

First let me say that I love the manifold, it's seems very well designed and for a race car application is is so much cleaner looking And simple vs oem. This is on a 1.6l car so all the oem upgrades discussed in this thread don't really apply to me.

I have had some problems with the welds on my manifold. The first runner has cracked at the weld twice before, at the manifold, so I built a brace between the first and second runner, but it then cracked again.

I also recently did a boost leak test to troubleshoot some power loss issues and discovered a hairline crack 80% of the way around the #4 runner at the plenum. This isn't a place that supports weight and is very bizarre to me. While diagnosing these issues I found two other pinholes in the welds in my particular manifold. Has anyone else complained of these problems or had similar issues?

Here are some pics of the locations.

Cracked on the top and the bottom of #4 but not connected in the middle welder said that the crack really opened up once he started welding it to repair it.
https://www.miataturbo.net/attachmen...ine=1460658097

Pinhole in #3 in the weld
https://www.miataturbo.net/attachmen...ine=1460658097

Pinhole in #2 by the flange in the weld
https://www.miataturbo.net/attachmen...ine=1460658097

#1 crack
https://www.miataturbo.net/attachmen...ine=1460658097

Again, I'm not trying to pour salt or damage anyone's reputation, just some problems I've encountered and kind of want to hear if anyone else had the same experience or if corky has seen this before. I do really like the manifold a lot but I don't want to keep chasing cracks.

Those sound like vibration cracks. Which can be cause from many different things. Did the support brace help? What motor mounts are you using? what is your rev limiter?
Thanks,
Stephanie

The motor mounts are solid metal, the limiter was 7200 spark cut and is now 7500 spark cut.

The support brace initially was only 1 piece of flat stock from the flange to the plenum, which cracked once, so I added another piece of flat stock from the middle of the brace to the top of the flange. This time the brace didn't crack but the runner cracked again in the same place

:giggle:

I would guess that it is the bolded part that is causing the issue.

How so?

I know solid mounts increase vibration/nvh into the car, but that's not the discussion here.

I'd say it's relevant to the main cause :dunno:

Pinholes may or may not be due to welding.

so 'splain to me how it's relevant

also plz 'splain to me how pinholes in a welding bead can be anything OTHER than bad welding?

Increased viberation on dem' thar solid motor mounts makes for a hootin wobbly mani for some cracks to form.

Pinholes may not even be pinholes but small cracks forming. Though bad welds would cause pinholes :likecat:

Cracking at the beginning of the runner would support guesses that the vibration caused the cracks.

how does a solid mount increase vibration to a part that's already on the vibrating engine

The purpose of engine mounts are to reduce vibration by taking energy from the engine moving (the vibration) and dampening it (turning that energy into heat). This reduces the movement of the engine. That's how dampers work, whether it's engine mounts, dampers on your suspension, etc. No dampening will result in more movement.

Regarding the manifold posted, as already said holes are from bad welding. Cracking could be several things. Multiple cracks suggest a fatigue failure. My first guess is the design is the problem. Thin metal hanging unsupported, it vibrates enough to cause a fatigue failure. Solution would be to use thicker materials, reduce the overhang to reduce loading, or brace it to reduce loading. My opinion is that while solid motor mounts aren't ideal, whatever manifold you're running should be strong enough to handle that no problem. I'm sure the OEM cast manifold would run a million miles without cracking on a BP with solid motor mounts, because it's strong enough to no fatigue fail under those conditions.

As an example, here's a stock miata manifold. It's FULL of bracing cast into it for strength. That's there for a reason.

https://www.miataturbo.net/attachmen...ine=1460674011

There is no give to the harsh vibrations or anything (rubber) to dampen the increased nvh.

I guess an example would be upgrading to stiffer motor mounts that increase nvh and shake the entire vehicle. Having a solid mount must rattle everything else like crazy.

Tie in a connected intercooler pipe & plumbing to a mounted intercooler, maybeh it's pulling & pushing on the vibrating manifold :jerkit:

OOoooooor, some weak welds to begin with :dunno: The increased nvh & vibrations probably don't help the situation.

that's where I was going with it: it might not be helping the issue, but I really don't think it's the main reason for the crack.
I think the main issue is a weak design, followed by bad welding.

Yeah. If I designed and sold an intake manifold, it would be designed differently. At a minimum to keep to the design of BEGIs manifold, I'd weld in bracing by the flange and plenum, much like the braces cast on the OEM manifold. But I'd take the same approach the OEM would take, make it strong enough that it never fails, not strong enough that it shouldn't fail.

get in a miata with solid mounts and youll understand right away.

we're talking about the engine.

not the car.

I've driven one with solid mounts actually.

I will say that my local welder said the original welds didn't look great, that they weren't hot enough. When I mentioned Bell/Corky he initially looked shocked, but maybe took a guess that they subbed out the welding and perhaps had been welded by someone a little novice.

Again, I'm not out to bash, just trying to see if this is common or just a me thing, I don't know how many people even own these things, they aren't exactly "inexpensive".

I keep laughing at how you guys don't seem to get what Vlad is saying.

Engine vibrates. With rubber mounts, me no feel vibration. With solid mounts, me feel vibration.

it's like you guys think that solid mounts actually make the engine itself vibrate more. that doesn't make any sense. engine vibrates the same, no?

the frequency of the vibration might change, from the dampening, but I don't see how the intensity would

The same with or without dampening? No, it's going to lower the amplitude when you dampen it. That's what dampers do, they remove energy from they system. The frequency will stay the same, that depends on the RPM of the engine. The amplitude will decrease the more you dampen it. Very simple physics.

But the motor mounts only dampen and isolate vibration from the chassis, not dampening the vibration to the intake manifold. I don't see how isolating vibration from the rest of the chassis would also change the vibration experienced by something that's hard mounted to the engine.

Same reason bolts vibrate off engines with solid mounts. Because the movements arent damped. With soft mounts the engine vibrations are damped.

Not true. Example, someone replaces crap dampers on their motor mounts suspension. The user notes that the dampers changed the handling characteristics of the vehicle regarding the suspensions ability to keep the tire contacting the ground, and the ride comfort of the vehicle. The car is faster around a track (tire control changed), and yet also has changed the way the entire chassis feels. The reason it has an affect on both is because it's connected to both.

Because the dampers are dampening vibration. It's what they do.

We have a winner! This.

dampen and reduce resonance.

Ok, I see what you're all saying. Carry on.

so back on topic:

is BEGi going to fix their poorly welded broken manifold?

Most places that appear to be holes are not actually holes. They are where the tip was lifted when welding or a weld covers another one. It can create a small black spot that looks an awful lot like a hole but isn't. But, because people will perceive them as "holes" when they aren't - I am EXTREMELY OCD about the guys covering those up or fixing it. It saves comments or emails such as this. It is easy enough to test to see if it is a hole or not. Does light shine thru it? Will a small paperclip push into the hole? I have no idea how old this manifold is, but we would be happy to fix it.

As for the cause of failures, ya'll nailed it on the vibration. Now add in the G forces that engine is under at an increased rev limiter - and I'm not surprised there is a crack there. Say you create the perfect storm - solid motor mounts and you're about to shift at red line in boost, in a corner, and then hit a bump - vibration, G force, and pressure. IF something is going to give it will be the softest metal or the weakest link in this equation, and that is the aluminum in the intake manifold.

Like I said, we'd be happy to fix it. Just give me a call. Also talk to Corky about additional bracing to try and avoid future cracks. As long as solid motor mounts are used, though, I would expect that you will continue to fix cracks occasionally.
Stephanie

The pin holes are in fact that, I did a boost pressure test using soapy water and I sprayed down the manifold. If I continue to have problems I will contact you guys at BEGI I have another event on the 23, I will check the manifd again for boost leaks after I finish reinstalling it, and then again after I go to the event to see if I have more problems.

It's kind of crazy to me that solid mounts would be an acceptable reason as to why a manifold would crack, but I'm not an engineer. I will add some pictures of my current bracing and setup to give you a better picture.

Thanks

Solid mounts make lots of things not happy. Engines should not be solid mounted.

We refuse to sell anything beyond a 70A AWR motor mount for a very good reason, folks. BTDT. Got tired of tightening subframe and PPF bolts.

Solid motor mounts break things. Don't use them.

Unfortunately, I don't have much choice because of my swap.

Sure you do. Id have to look at your space constraints, but theres no reason you cant fit a bushing in there. FC right?

Like, I said we'd be happy to fix it. Email me for a RMA form and send it in.

Bracing will help, but will not be the "be all, end all". Corky can help with those ideas. It is much like the Stainless S4 manifolds we use to sell. The weight of the turbo had to be supported as to not crack, however, it still had to be able to move because of thermal expansion. Regardless of what we did, the stainless was never strong enough and this manifold would crack at some point no matter what. And sometimes, the more you brace it the more it cracks - espcially if it heats up and moves.
Stephanie

I did a leak down test today and immediately heard leaks coming from the my intake manifold. I found two pinholes and a cracked weld. I am not the original buyer of the intake so I don't know all of its history. The pinholes are on the 1st and 2nd runner and the crack is on the first runner. I searched here to see if its a common issue and found this thread. The pinholes are near the injector and you can see where either fuel has been seeping out or gunk has been making its way into my engine. I have already sourced a local shop to strip the intake of the blue paint, repair the damage and pressure test the intake.

https://cimg7.ibsrv.net/gimg/www.mia...7e75be5f7e.jpg
https://cimg8.ibsrv.net/gimg/www.mia...59f42f281a.jpg
https://cimg3.ibsrv.net/gimg/www.mia...5c7f5a1ff3.jpg

I don't know if the pinhole leaks were from when BEGI built it, or from vibrations. I have heard of a good number of weld failures with honda IM conversions. The consensus I have seen seems to think it most the vibration of the engine that causes issues. I have also heard from various spec miata drivers that without the stock brace IM manifolds have been known to crack and break studs due to vibrations.

I went ahead and blasted the paint off to see what is going on.

https://cimg7.ibsrv.net/gimg/www.mia...4eab7c193b.jpg

After it is repaired I'm going to have it powder coated, but I kinda like it blasted.
https://cimg9.ibsrv.net/gimg/www.mia...3847ee6a07.jpg

If it is cracking along a weld, that is a vibration. I see a small hole in the crack, but that does not look a welding issue. Do you have a better photo?
Thanks,
Stephanie

That crack may have been exacerbated by vibrations, but it sure as hell looks like an incomplete weld to me.

:laugh:
Stephanies SOP:

https://cimg2.ibsrv.net/gimg/www.mia...ec393b51dc.jpg
This is from an angle that is different than the others. Let me know if there is a specific area or angle you want to see.

The only way that might define if the hole is a welding issue is if the manifold had a leak from day one. If it was okay, but later leaked, chances are that is a hold from the welds cracking. If you had a vacuum leak from day 1, that might be a different story. That might be hard to determine since you pick up the manifold used. We'd be happy to fix it if you can't find someone local to repair it. Make sure they get the area for the injector seal flat or you will have another leak. Just give me a call.
Stephanie

I would not powder coat it as that's going to make rewelding cracks in the future a huge pain.

I took it to a local welding shop today and was told the original weld was too hot and undercut. The welder did not want to touch the intake. I will contact you soon regarding the intake.

Try a different welding shop. I can't say if there are or are not bad welds there, as I am horrible at welding aluminum. But I have had several different welding shops tell me stupid things like that just because they did not want to do the work.

Sounds like a welder who is not up to the task and trying to blame someone else. Find a new welding shop or give me a call.
Stephanie

They either stopped that weld short to not get into the injector recess, or machined too much away when they machined the injector recess. It was likely either never sealed after machining, or was so thin it never stood a chance. It's going to be a bit of a PITA to fix properly, and will likely involve hogging out a good bit with a burr bit and having to grind the port interior when its done, in addition to re-machining that pocket. That porosity pinhole didn't help, but wasn't the cause of the failure, and weld quality likely was not, either.

Thank you for never calling me back! I found someone locally to weld it for a quarter of the cost you told me!

How is BEGi still around?

Good question! I swear the customer service all depends on the day you catch them on. Corky has rewelded my intake manifold twice for the cost of shipping. They did try to claim the cracks were due to my AWR motor mounts. At the end of the day they fixed it though. For the money I would never recommend anyone buy this manifold. Too high of a chance you end up with a $800 paper weight. It does function pretty well when it isn't cracked though!

I was told 2 hours of labor at $95 and hour to repair the intake. Stephanie and I talked about updating the intake to their latest revision with injector bosses instead of holes drilled into the flange. She was going to check with Corky and call me back, that call never came.

Any intake without a brace is asking for trouble. I've seen this issue many times, the intake brace is there for a reason. These engines have a high NVH (noise/vibration/harshness) and will only get worse if you use racing engine mounts.

I think this is a really relevant point. If I was to ever make an aluminum intake I would not offer any sort of warranty on it. I don't honestly believe you can make a welded aluminum one that is long term track reliable on a miata motor. Eventually the NVH will cause it to crack. Bracing it should help, but I am not sure if it would still make it something that would never crack. Also the fact that you can make 400+whp on a stock manifold makes going to an aftermarket one sort of moot in my book. You will be breaking other things before you really "need" an aftermarket IM.

I am sorry, but I cannot make Corky call you back. I give him messages, I remind him to return calls. If he won't give me back the information plus the information I need to help, I can't call either. I am sorry my efforts were of no help.
Stephanie

Aren't you the one who handles most of the communication?
I'm afraid we need proof of life for Corky.
Please post a picture with him holding a dated receipt for a bottle of cuervo.

Be careful! You may receive an infraction for BASHING a vendor on this forum if you continue to pursue the unprofessional business practice of BEGi or their subsidiary companies. It happened to me after I received the world's crappiest intake manifold and demanded everyone know about it. They can't handle the truth!!

I got that PM infraction too, but it was for a different vendor, and in a different forum. Out here, even the mods DEMAND that BEGi steps up their game, so you should be fine.

From what I have seen, some MODS choose to back the failures of said company.. through issuing out counter complaint posts and these PM infractions on Miataturbo in attempt to discourage voicing members discontent of purchased products from said company. And still there is no improvement of said company's GAME. Same as it ever was...