I just got my car running on boost and I'm having trouble with boost spiking. I have a .6 bar(9lb) spring in my wastegate. When the thing hits boost, the boost spikes to like 14-16psi. I disconnected the boost controller because I thought this mite be a problem and I am running a vacuum source straight of the intake manifold. It still does it.
I know its not the manifold becuase its a Full-Race Manifold and I really dont think its the wastegate because I really dont think Tial 40mm's go bad this often, plus its brand new. I'm running 3/16 vacuum lines to everything. I checked for vacuum leaks, kinks in the lines, and there is none. Could this be happening because I'm running an open DP and I dont have a dump tube on the wastegate? I'm stumped.
Here's the set-up

84mm GSR motor
Skunk2 Intake
Full-Race Kit
T3 60-1 turbo
Tial 40mm w/ .6 bar spring (little blue one)
Greddy Type-S BOV
Hondata
96lb Injectors

Any input would be greatly appreciated... Thanks guys

 

are you sure you got the .6bar spring in the wg.

The tial 40mm doesnt usually spike even if you running open downpipe. As long as you got a good vacuume source then it should work with out any issues.

is the boost even holdign at 14psi or is it fluctuating up an down

 

Damn, that was quick. I'm positive its a .6 bar spring. Its a small blue one, or am I wrong...

 

are you sure open it up and check it out. also is the boost holding steady at 15psi or is fluctuating in gears.

I am thinking you have the 1.0 bar big blue spring

 

I just got done double checking that, It's the small blue one. It had a big red one in the wastegate when i got it, .8 bar, so i have something to reference it to when I compare the sizes of the spring. Plus, the .6 bar spring was shipped direct fro Tial when I ordered it. Gonna try re-routing the vacuum lines now and give the WG its own vacuum source.... Here I go

 

OK... I just tried running an independent vacuum line to the wastegate and its still doing it. I checked for exhaust leaks around the manifold and there seems to be non... Oh, I'm using the side vacuum port on the wastegate. Thats the correct one to use rite??? Any more suggestions anyone???

 

Try tapping the WG signal as close to the turbo compressor as possible.

 

Ok here's the latest... I double checked the WG spring and it is a .6 bar. I found a

small exhaust leak where the DP flange bolts to the turbine housing, took care of

that... i got rid of the banjo fitting on the wg and put a regular barbed fitting on

there... Double checked for vacuum leaks...The end result = still spiking to 14-

16lbs. I'm starting to think that theres something wrong with the WG, but i know

this rarely happens with Tial gates. Anyone have any suggestions, I'm stumped

Thanks guys

 

I have the exact same problem with mine. The higher I rev the higher it boosts. I have a digital boost gauge as well and it rarely stays at .8bar if I rev past 8k.

 

search 0wnz j00...

https://honda-tech.com/zerothread?id=749007

 

you and EK are two of the three that have had this problem.

btw mike, its really strange becuase on steve jungs car with a 35mm gate it *never* creeped, and that went to 9k too WITH a little baby WG

 

also --

have you checked all of the bolts on the turbine housing to the center section, also checked the WG to make sure there is no leak there, or checked the turbine to manifold surface, as well as the head to manifold seal ?

Its odd to hear this becuase i have a straight t4 gt-p trim t67 as well as many others using huge turbos with no probs like this at all, my car holds 10.0 psi consistnetly

 

I wonder what the pressure is inside the wastegate mount tube as opposed to the collector it connects to? Maybe sorta OT... just a thought tho... I can't really see them being that different, maybe if the wastegate tube was smaller...

 

when you are using a 40mm tial WG, the wastegate tube is actually under one inch...

 

mike if you want give me a call and you can borrow my 38 tial to see if its a wastegate problem.. i was having a small amount of creep in mine too... from 7000-8000 it would spike a couple pounds but hey if you want to check it out with my wastegate before i put the motor back together let me know...

 

Sorry to bring this post back, but I'm trying to get this problem solved.

So i've made sure that there are no leaks around any of the mounting surfaces of

any of the turbo components. I have an exhaust on the car now as well as a dump

tube. The exhaust has slowed the boost creep down alittle but I'm still getting the

same 14-16lbs spikes. I'm wondering if I need a bigger waste gate. I know a

40mm is pretty big and I've seen people with similar set-ups have no problem

with boost creep... So anymore ideas on what the problem is or suggestions???

P.S. If u read thru the post, u can see what I have done so far

 

bump... anyone

 

morning bump... anyone got any suggestions??? Thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by danl &raquo;</TD></TR><TR><TD CLASS="quote">Try tapping the WG signal as close to the turbo compressor as possible. </TD></TR></TABLE>



You need to source it from the manifold.

 

I'm running a source straight from the intake manifold. There's nothing else hooked to this line except the wastegate, and the boost controller isnt hooked up either. I'm using the port on the top of the plenum were u usually where the pcv system feeds back into... Thanks for the help ... anymore suggestions?

 

afternoon bump...

 

Ok, i replaced alll the vacuum hoses, double checked for leaks in the vacuum lines

and all the IC piping as well as the exhaust. I also put a 12lb spring in it to see

what happens and I'm still getting the 4-6lb spikes. I pulled all the turbo

components off to see if there was any leaks on the mating/mounting surfaces

and there are none. Also when I changed the springs in the wastegate, I checked

for tairs/ rips in the diaphram and there are none. Another thing i noticed is that

the wastegate doesnt seem to be opening that much. When I look into the outlet i

can see the clean spot on the valve that shows how much the wastegate opens

when the car is boosting, this clean spot is only about a 1/4 inch. If u push on the

head of the valve, with the spring out of course, and u open it up to the point

where the clean spot is, it doesnt seem to be opening that much. I'm not at all

sure how much a wastegate is suppose to open.. I guess it all depends on the

boost level... I'm beginning to think i need a 46mm gate... any suggestions

anyone... sorry for the length...

 

It may be a defective gate...Contact Tial or the seller you bought it from and see what they can do...If worse comes to worse, sell it as a gate thats setup for 14psi and get another one...Find someone else with a 40mm gate and try theirs if possible...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Sunrise City Rider &raquo;</TD></TR><TR><TD CLASS="quote">It may be a defective gate...Contact Tial or the seller you bought it from and see what they can do...If worse comes to worse, sell it as a gate thats setup for 14psi and get another one...Find someone else with a 40mm gate and try theirs if possible...</TD></TR></TABLE>

Thanks for your input
I'm beginning to think that the gate might be defective. I want to try someone else's gate but everyone I know has either a Tial 35mm, 38mm, 46mm, or some sort of HKS gate... just my luck...

 

Boost spike problems usually arise from crappy rubber hose being used on the wastegate actuator.

Options to consider is steel braided line.

Now, you said you're boost spiking.. does it eventually go back down to .6 bar? or does it keep going up the longer you're accelerating. If so that's boost creep and that's probably due to too much exhaust flow through the turbine and not enough out the wastegate.