Setup consists of..
-Billet wheel hx40 evo on built motor/bulls-eye power undivided T3 backside
-3in Down pipe
- 1 1/4'' runners, 17* collector angle, 1.5'' wastegate elbow
- Tial 44mm
- Dead straight 2'' dumptube

Customer says it is spiking without stopping. Literally says, will keep going above thirty pounds, and also that he tried running it with no spring.

-Design wise i could not think of a solution as to what i did wrong, and the original tial 44 he had had to be sent back to tial cause of a bad seal. After it returned the issue persisted. I ordered him a brand new tial 44, he tried again, and it still spikes.

- This particular customer is not stupid, he built the motor on the car and is very thorough, as he lives 3 hours away i havent gone over it in person but would be very surprised if he botched installation. i tried to get him to verify via air compressor that the gate opens with his own eyes but he does not have access to one.

- The manifold is ceramic coated, id prefer not to cut it open to change the wastegate elbow, especially when i cant really see what i did wrong and would not be certain anything id change would even work. I have ordered a 2in flex bellow from vibrant and will recirculate the wastegate at a high degree angle to reconcile the issue. However it still irks me as to what i did wrong and would just like some incite as to how to avoid this problem in the future, or special concerns to watch out for with this particular motor.

I've put externals on a good amount of other cars, and not had any problems, and some were complete 90* elbows.

Manifold was done a while ago, go easy on me lol.

Dumptube/ wastegate

Good view of downpipe/ wastegate dump. Is it possible the tight radius is causing issues?




Here's pics of the collector incase that may be the issue





Sorry for all the pics, but figured id post as much as i could.
- Could the collector be too short? I've seen many others as short as mine, is the elbow too large? If so, how could a +- an inch difference result in THIS serious of a spiking problem? It is teardropped and purged. idk.

- I have seen issues with the Tial 44mm with multiple springs, actually another thread on this forum. But the customer said he tried it with no spring at all, so that would seem to rule that problem out pretty quickly. Any potential issues with the gate that could be overlooked?
*Also keep in mind this is moch up. Obviously he knows to connect vaccum lines. Thanks for any help and incite you can offer.

 

There is nothing wrong with that manifold or wastegate elbow/design. It actually looks great.

Even though you said you have replaced the wastegate, id be confirming vacuum lines etc.

 

I would have to agree that manifold and dump tube and dp look great.

questions
1-where is he getting vac/boost source for the gate
2-does the engine run right? bigger cams? ive seen this on honda stuff where the car is in limp mode causing the turbo to spool like a very large turbo like it was a t25 witch in turn would over turn that gate even if it was off the manifold? so i ask if it has different cams and maybe installed wrong?
3-boost controller? what type?

 

- Source for wastegate is coming directly off of the turbine housing.
- I rode in it before he blew the motor because of some water down oiling issue. It ripped pretty hard. Not really as much as I expected tho.
- yes, I do believe he's running kelford 272's.
- not sure what EBC he is running, but I do know he said it is worse with it connected. At the moment I think he's diagnosing with no EBC connected running off just the spring.

I appreciate the feedback, it does make me feel a bit better I suppose. He was talking about getting a jdl mani and such. I would be very offended if a manifold swap resolved the issue, and feel shitty that one of my parts is even causing a potential issue.

I'm gonna get him to lurk on here/ register and maybe he can chime in to fill in any diagnostic pieces I missed.

 

i dont think your manifold is the problem i would almost put all my money on it most spiking problems with manifolds come in the top rpms also ive seen some really shitty manifolds make good power and not spike lol

 

I would pull the gate apart and check the diaphragm for any sort of holes or overheated issues, I know that the new gates need the water lines hooked up so they don't melt down. The gate entry looks great and really does not look to be a issue to me.

 

Single gate off the side of the collector like that just doesnt cut it on some efficient setups. If he ran it with no spring then that right there tells you one is not enough.

 

Its a t3 housing with the gate completely off the thing shouldnt boost at all unless the turbo is way under sized for the setup witch is doesnt seem to be.

 

There are many forward facing kits with very similar design and made for the size turbo he is running. I really do appreciate all the responses. I am at a loss with this car.

Im going to stick my air compressor on it. Just to see if its opening and we'll mess around with the gate when he brings it. i'll also inquire about the coolant, but im pretty sure he is running it. As of now, he's bringing the 02 housing, manifold, turbo, and wastegate. And im gonna recirc it off the car with as much angle as i can. If this dosnt resolve the issue i really dont know what will (assuming somehow it is not getting enough flow to the wastegate). Im planning on brining it in almost parallel with the 02 housing to maximze "Bernoulli" affect or whatever the ****.

Runnerdown- is it possible you could elaborate more upon why an efficient motor/ exhaust setup would inherently have restricted flow to the wastegate?

Thanks again for the input.

 

Take the gate right off and try running it. If the turbo and ex system flows well enough the exhaust will not really pass through that wastegate opening. I have seen this a million times and the solution is to add another gate or change the manifold layout which is not practical.

 

While there is a little bit too much angle on the wastegate elbow, I don't see it causing runaway boost. That is going to be some form of wastegate failure there.

With that setup, I wouldn't be too surprised to se 2-3psi creep on the top end with a really efficient car/turbo, but nothing like you are talking about.

 

Take the wastegate completely off, if it still creeps then you either need add another wastegate or do something to add some back pressure into the system (smaller back housing, add exhaust, recirculate the dumptube). If its easier for the air to go through the turbine, then thats what it will do. With todays turbines flowing much more then previous ones at the same size, wastegate sizing is even more crucial.

 

Makes good since

 

I tried to get him to run the car without a gate before, but hes not to keen on the idea of dirtying up the bay. I just tried again to see if he could do a single pull down his street post warmup without the gate, but hes saying how its the same with no spring in the gate. Which it is, assuming the wastegate opens. Which he said it sounds like a massive leak with the spring out so. It prolly is the mani i guess, and if the recirc fixes it i guess that'll let me know for sure. Its just gonna be gay recircing this setup without doing everything to isolate that it was the manifold.

Thanks again for all the input, i'll post back when i finish the recirc setup and see what's going on with the car after that.

 

Came in to agree on running it with out the wastegate.

 

I'm gonna have to disagree with the majority here....

With the short collector it's not giving the passenger side 2 cylinders a chance to evacuate the energy via the wastegate. That's why you're having severe creep issues. If you put another gate on that side you won't have any more issues, but that's not because you have more outgoing flow, but because you finally allowing the farther runners to breathe.

Short collector = less time/chance to evacuate energy.
Long collector = more controlled flow and better chance to control energy.

 

With that in mind do you think it will still be a toss up as to whether the suction from a high angle recirc will be enough to reconcile spike issues? If not I can cut the mani open, but I dread telling him to pay another $340 for a second gate because of my own design flaw. I did this manifold, down pipe, and dump tube for 600 including materials (was my second exhaust mani). I'd much prefer to not have to cut into the mani again and sink myself even further in the hole, as I am at McDonald's pay wage as it is. and thats not including the flex for the recirc, and the money I just put up for the second gate.

Honestly, the length of the collector makes sense to cause that issue. If the pyramid is that close to the flange then it might not have enough time to merge.

I always thought of the exhaust air next to a turbine/flange as being very turbulent and creating a lot of back pressure and backlash, which would seem to push air through the gate hole naturally. But I suppose on an efficient flowing head and backside wheel that is not always the case, and it must be shovin that **** right in there and not goin all caddy wampus as I thought.

Again thank you all for battling back and forth on this with me. There's no where else on the net I could go to get input from dudes that have built a bunch of manis. Before I move forward fixing something I always like to understand my mistake.

 

I don't think the recirc will fix anything, but that is just my opinion. Playing with the pressure delta across the turbine side is a terrible bandaid.

Now you know what to do in the future. It's part of learning and proof that you can't just throw something together and expect it to be flawless. Nothing is perfect.

 

I would go over everything else with a fine tooth comb first, I still have a hard time believing that this manifold, without a spring, will go past 30psi.

2-4? Yeah, definitely, but 30psi+ spike is insane for a T3 housing and 44mm gate at the collector.

 

I cant find a pic of the wastegate side of their t3 mani. But from this view it looks very similar minus their runner path's. Short collector, single 44 gate, bout the same length elbow. Theirs may be slightly turned down more than mine.

I wish i could go over the car in person, he lives 3 hours away, and is becoming more frustrated as i pry further to try and diagnose. He's pretty busy generally, and i dont think he wants to go through the logistics of leaving the car and finding transportation etc, or even trying to diagnose the car any further. Yesterday he was pretty damn short when i tried to get him to run without the gate, and seems convinced the manifold is the issue.

So he's bringing me the setup off the car and i'll recirc the gate on a hunch. But like you said, i still have a weird feeling there's something off. Spiking that bad. ima be feelin shitty the whole time im recircing the gate, crossing my fingers like a ****** savage hoping/praying to some god that its gonna work. Like you said, its just a lotta damn spike for very minor differences in manifold design.

Honestly, i dont quite see how its a band-aid. Considering any manifold with a single wastegate on it is going to scavenge air away from one side of the turbine. Whether its being pushed, or whether its being pulled, the same amount of exhaust air is being diverted. Dont get me wrong though, pressure delta is a cool sounding phrase.

 

What wastegate spring is he running? I have a TC here that has a super short collector just like yours, with the wastegate completly removed it made 12-13psi, had a 5 psi spring in it, on the dyno it made 18psi. If you customer has say a 15 psi spring and the manifold produces 12 psi with no wastegate I could see 25-30psi out of it.

Truthfully as said a taller collector is needed to allow better sampling of the wastegate, with that size you need to add another wastegate (as a bigger would not fit). I would just eat it on the labor and material to add it and dumptube and offer him a wastegate at cost to get him going and happy and reevaluate your manifold design.

What your going through is common, everyone and their mom was offering t3/t4 single 44 k series sidewinders, and they all boost creeped with a decent turbo. Now you can only get them in 60 or dual 44 gates.

 

He tried a 3psi, 5psi, pretty much he said he tried about 12 diff combos; all yielding the same results. Meaning, he'd hit 30psi @7500 and let off before it could go any higher.

Thats really interesting that you were able to get it to hold boost on that car. Not sure whether that is due to a large displacement motor, if i recall the tc is a 2.4? I know on ka-t setups wastegate routing was never an issue to my knowledge unless you were downright negligent and those motors are the same displacement, but also space constraints arent very demanding on KA's. So collectors end up being longer inherently anyways.

Thanks for the input man, I need to make a new collector jig with a more shallow angle, and or start making mani's with a piece of pipe on the end to the turbo flange and have the wastegate come strait off of that. **** though, buying two gates just sucks nuts lol. Def is lookin like you gotta pay to play when ur ****** with da big boyz.

 

30 psi creep with a 5 psi spring, no way. He needs to pull that wastegates completely off and do a solid pull and see what it does. If it doesn't creep then it's either vacuum routing or a damaged wastegate. You could be chasing your *** on this one, but defiantly for future, keep a longer collector going.

 

Thermal expansion of vacuum?

How are you using a material property and an absense of material in the same sentence?

 

i couldn't agree with you more. it definitely sounds like a bad wastegate or a wastegate that is not seeing a proper boost signal.