the lower psi springs are fairly soft. I have a green TiAL spring (don't remember if its big or small) and I can easily compress it with my fingers. the higher psi springs are much stiffer
remember the spring rate determines boost pressure so a softer spring equals less boost

so don't stress it, the spring is fine

 

Cool thanks... that's what I thought but am new to turbo setups I always been an all motor guy...

 

I'm leaning towards the manifold being the culprit as well. that's a pretty poor manifold/wg design, very easy to have flow problems at higher rpms and higher pressures

 

changed out the wastegate looks liked it fixed the issue..thanks for the help guys

 

sorry if its a little off topic but my friends selling me this wastgate (on the car now) manifold, and 3in down pipe for $450 good deal? lmk what you guys think. btw the my motor specs are lsvtec 10.1 comp 84mm Garrett GT2876r.

 

I still believe that most Honda users on this forum simply aren't used to platforms and similar VE'd cylinder heads that utilize this type of manifold and simply don't experience the theoretical exhaust energy restrictions or backpressure issues that they believe people who use them have. Using similar manifolds in platforms that experience over 20-40% more boost pressures and higher backpressure ratios is very common; it just that most here jump to that inference and then think that going to a "Ramhorn" with larger runners is the only answer to such an issue when this manifold has literally been used for years.

Here is a video example of the Top Fuel EK9 civic from 2001 using the same manifold and used in Super Lap Racing.. at the time , 59 seconds was considered pretty fast for a FWD car at Tskuba Lap (currently the FWD record is about 58.2 seconds from a 5Zigen FD2)




But here's what that kit consisted of...



engine : B16B (extend to 1800cc)
turbine : BLITZ K3T
cam : in 280 ex 280
compression ratio : 8.5:1
Injectors : 550cc x4
ECU : apexi Power FC
final ratio : 4.8

But they used a Blitz External gate on the same manifold pictured at over 2Bar of boost pressure. I'm sure Tony the Tiger will give a bit more of a numerically representative post regarding the use of these manifolds, but I'm just talking as a matter of utilization as compared to always going to a "Ramhorn".. These work well.. Limited in their use, but not to the point where this person would have backpressure issues for a spike.

Time and his report back will only tell, in the end, and I'm probably still too sick to go more in-depth right now, but let's try one solution at a time first, ya know? But that's just me. Makes no sense for this Huge manifold smaller turbo combination trend that's been recommended lately.

 

For just a GT2876R? Really over kill for this.. But, that wastegate flange can only fit the F40 TiALs from a few year back (IIRC the F41s were discontinued and would be the only other flange that could fit that.)

I wouldn't get it.. There are simply tubular log and min-ram manifolds for the same money that can be more easily configured that are brand new.

 

ding ding ding! WINNER!

manifold design (or lack thereof) contributes to most of the boost control issues people are having. Seeing how most manifold companies simply "copy" other designs, little is done in the way of wastegate placement... Some add a tear drop shaped wastegate elbow hoping that te curvature will force the exhaust gas boundary layer to follow that contour and suck exhaust gasses in with it.

For truly rock solid boost control with no creep, you need a manifold where the wastegate gets first priority on exhaust gasses leaving the head, a good example of this are the sidewinder manifolds where the wastegate is on a 90* bend then the turbo bolts to the bottom of that elbow, directly in line with exhaust gas flow, allowing it to vent as much pressure/flow around the turbine as the wastegate size will physically flow at the boost levels it is trying to control

Just look at the old turbo F1 , CAN-AM motors, turbo CART motors, as well as the Indy Racing Leagues new turbo cars... You'll notice that the wastegate is directly in-line with the exhaust gas flow as it leaves the head and flows through the manifold, then the turbo gets mounted on an elbow below the wastegate, giving the wastegate first priority and the turbine second. basically identical to how the sidewinder manifolds are setup.


as far the manifold you posted pics of, unless you have the old 4 bolt TiAL 40mm wastegate you're **** out of luck... they stopped production on them years ago and they are rare to find. You could always have an adapter made to fit a 44 TiAL.. I still see you having boost control issues with this manifold... it might be time to look at the turbine wheel size and turbine housing size.. the combo of a poorly designed wastegate, and the turbine side coming into play here as well, it might take awhile to get your spiking issues under control.

 

Sorry guys just incase there was any misunderstanding it was the wastegate causing the spiking problems. The ram horn manifold is not installed on my car, he is selling to me. And just wanted some input if its a good deal, and this ram horn fits a 38mm hks wastegate.
The only reason am swapping the mani is because my tuner said with a decent ram horn manifold I will see a minimum 40whp increase at the same psi.

 

Yes, however it will be in the upper rpm band and not in the midrange. So, its like getting higher peak power, but not where something like what it seems that you're trying to do would be optimal. That's why there are other types of manifolds to fit the bill other than just a "Ramhorn".

Here.. check this out here before making a final decision.

https://honda-tech.com/forums/forced-induction-16/why-top-mount-2152865/

Now what part of the wastegate did you find was particularly faulty? seizing valve? spring not actuating? etc

 

I just swapped the whole thing out with the one my friend lend me. Am still trying to get mines tested the way turbohatch96 said..

Btw theshodan thanks for the info, I will read it when I get home.

 

Head to home depot get a 1/8 npt brass plug, cap the top port and with an air gun feed the bottom port. Air guns are usually tapered at the ends so itll fit in snug.

You could rig up a better way to feed air in but that is the simplest and fastest way.

You should really make it a point to test the bad wastegate for future reference. That way if you come across the issue again in the future you know how to correct the problem instead of throwing parts at it.

 

I just test it at the shop, I didn't see any leaks only from the valve area. Btw It open all the way at around 20psi, its running a 7psi spring does that make sense to you guys?

 

that's normal. for the most part, higher boost equals the wastegate opening more, so at 7psi, depending on motor size and turbo size plus various other factors, the wastegate won't have to open that much.

about that ramhorn, your current manifold and turbo are t25 flanged, the ramhorn is t3 flanged... so you either have to get a new manifold, turbine housing, or turbo.

I still think your current issue is compounded by your wastegate problem. It's placement means you can only effectively bypass half of the engines exhaust gas around the turbine wheel.

our highly volumetric efficient engines, mated to a ball bearing t25 flanged turbo means that the turbo will be very sensitive to exhaust gasses, that is, it takes relatively little exhaust energy/flow to get them up to target boost levels compared to turbos with larger turbine and compressor wheels (as well as housings) this makes regulating boost especially hard, wastegate placement and size has to be perfect otherwise you run into the issues you're facing now... because right now you're having issues with bypassing enough exhaust gas around the turbine across the operating rpm/load range of the motor.

a bandaid in your case would be a larger wastegate, this would basically allow you to flow as much exhaust as possible around the turbine but ultimately the problem is the divided runner pair manifold design and your wastegate location.

also at higher rpms you probably have an issue with high exhaust manifold backpressure pre turbo and possibly a bit of exhaust gas reversion, this would be due to the smaller turbine wheel and housing choking from the volume of exhaust the motor outputs, when this happens backpressure rises as the exhaust gasses back up in the manifold (think of traffic on the highway, traffic being the exhaust gas. a restriction or bottleneck causes traffic to slow down or even stop, until enough cars get off the highway (bypassed by the wastegate) traffic won't speed up, causing issues with maintaining turbine shaft speed)

at least that's the best analogy I can think of, if it's remotely close lol

 

Did you keep the air in the wastegate? You add pressure the valve opens and keep the air in and watch if the valve creeps back down.

 

Any air that's fed into the side port is leaked threw the valve, after adding around 20psi it didn't come back down. So what do you guys think is wrong with this wastegate?



Its not spiking with this wastgate my buddy lend me, Its the exact same wastgate *** mines.
Btw thanks for letting me know about that ram horn monifolds flange not fitting my turbo

 

just looking out, I always try to help members when I can.

now it could be t2 flanged but it would be rare, as the manifold would have to be built to order with the t2 flange. most companies don't even list it as a flange option, it would have been a one off custom order for sure. but going off pics it looks to be t3 flanged... what did the seller say?

I picked up a new b series Neukin ax series mini ram for a deal, t25 turbine flange/38mm 2 bolt wastegate flange. if you're considering a manifold upgrade that would be what I would do. a t25 flanged miniram.

it gives you a definite flow advantage over the Greddy unit (i too have a b series Greddy manifold that I'm in the middle of porting, they are very restrictive, especially at cylinders 2&3) but it's short runner construction means you'll lose little in the way of response so you'll still have that low-end, midrange power your setup currently has... you'll just have more of it and better top end, not to mention having ideal wastegate placement, eliminating most boost control issues.

you can ceramic coat the manifold and turbine housing (or you could wrap the manifold with DEI heat wrap and use a DEI turbine blanket *to me they offer the best heat wrap and turbine blankets* or you could stack both, ceramic coat and wrap/blanket the entire hot side... this would keep every last bit of heat inside the manifold, meaning quicker spool up and more power, plus lower underhood temps... any of these methods would combat any heat loss through the runners. plus the benefit of lower underhood temps means your charge piping won't get too hot or heatsoak and it would help the car run cooler as all of that radiant heat is kept out of the radiator.

I would also advise wrapping the downpipe to lower underhood temps even further.

again this is all optional, the coatings and such, but when you get your turbo setup nailed down it's something I feel you should strongly consider

now, back to the miniram... you can't get one from Neukin, as his shop burned to the ground late last year but if you contact any reputable manifold builder they should be able to accommodate you.

another option is to find a good deal on a t3 flanged miniram and buy a t3-t25 adapter flange. they have units today that are no thicker than the turbine flange on the manifold so they don't move the turbo further down (only about half an inch max) and they are CNC machined with a taper which promotes smooth exhaust gas flow through the adapter plate. they are fairly cheap as well, the stainless steel versions are roughly 50-75USD, much cheaper than having a new manifold custom built.

 

Wow

 

♥

 

Nice great info, now I have to save some money for the mini ram, down pipe and re tune.

Now what you think about the wastegate test I did? What's causing it to spike?

 

Take it all apart and apply some honda bond to the screws holding the valve and for the top hat.

Then re test it.

Unless the diapraghm is ripped that should fix it.

 

Update, I just found one of the wires to the boost solenoid to the ecu was unplugged. Hopefully that fixes it.....

 

I put back my old wastegate and its spiking again. Is it normal for a wastgate to function normally on low boost (7psi spring) and spike on high boost?
Doesn't this point to a bad boost solenoid?

 

Did you try a different boost reference point away from the turbo? Or did you use the same hook up again?. And no, it's not normal

 

It's setup the same way my tuner left it, it wasn't spiking with the 14psi wastegate my friend lend me but I was running straight off the spring.