stock tt wastegates

[turbocat]

I'm driving my 89 callaway to Bowling Green for the 50th from California and I thought that I would like to race at Beechbend.I took off the mufflers and added straight pipes-it sounds so cool,also noted that the boost gage went up 4lbs - instant 50-60 hp. but- found that the lack of backpressure now created boost creep in 4th and 5th.,seems that the stock wastegates can not bleed off enough air to keep the turbos from over-boosting.Had to re-install the mufflers (and instantly lost 60 hp). Short of this-when you change one thing it effects other things that you don't consider. A larger wastegate would cure the problem but would take away the originality of the car.

 

[*89x2*]

TurboCat, Callaway now has a "beefier" spring for your wastegates which may offer some help - e mail Wayne at Callaway cars and he will advise you more on this. We discussed this extensively while a group of us were in Old Lyme this past Feb.
Hope this helps
here is waynes e mail:
wmccurdy@callawaycars.com

 

[turbocat]

It's my understanding that a heavier spring would only make it open later. I need it to bypass more air. Only way to do this would to have a larger gate that would allow more air to bypass the turbo. I have a 90 modded tt and the same thing happened. I had to go to a turbonetics race gate to cure the problem. The opening in the stock wastegate is to small to stop the turbo from over boosting.

 

[*89x2*]

Chuck, the beefier wastegate springs came into the conversation when one of the guys was talking about his increase in boost after making his exhaust "free flowing" I think we were also discussing the revised Wonderbar as well and how that can affect your boost levels - at any rate, Wayne suggested the spring for the WG as help for boost issues.
Hope this helps

 

[corvettecrazy]

you also might want to check out HKS, yes it is a jap. company but a very well respected one, turbonetics is also a good company, or you could get another callaway one

 

[turbocat]

re-installed stock exhaust and mufflers,went to road test-no boost creep. Went back to arcives at this site and found that others have had over -boost problems when cats or exhaust was changed. Since no one wants to believe what I have to say -this will be my last post-bye.

 

[*89x2*]

re-installed stock exhaust and mufflers,went to road test-no boost creep. Went back to arcives at this site and found that others have had over -boost problems when cats or exhaust was changed. Since no one wants to believe what I have to say -this will be my last post-bye.

Chuck, The race gas of course cures the symptoms of higher boost But I don't think that's what you are after(???)

Did you e-mail Wayne?

I know another CAC member was going through the same issues and was considering putting the cats back on - again, I am not sure what they have done.
Another member - maybe more have rebuilt their wastegate diaphrams however, that is different than what you have described.

Hopefully someone else will chime in (who has removed their cats) and offer what has worked for them - Keep the faith

 

[SurfnSun]

Geez man, don't be so touchy, people are just trying to help. Have you called Callaway yet? My over boost problem was diagnosed as bad gaskets on wastegate housing. Had nothing to do with my cat removal.

 

[90Callaway]

re-installed stock exhaust and mufflers,went to road test-no boost creep. Went back to arcives at this site and found that others have had over -boost problems when cats or exhaust was changed. Since no one wants to believe what I have to say -this will be my last post-bye.

I haven't been around for a few days so I could not comment. I also had an immediate boost increase from 54-56hg to 58-60hg after going from stock mufflers to Magnaflow high-flow mufflers. (The cat was already removed and if I add it back for emissions it brings me down to around 52-54hg.) It's a huge change in boost based on exhaust back pressure. I was able to adjust it and keep it in the 56-58hg range which I'm comfortable with based on the stronger internals of my engine and a mix of race gas and high test unleaded.

I agree that what you say makes sense. A stiffer spring is just going to delay the opening of the waste gate and probably make the problem worse since you will be WAY overboosted by the time the spring opens and bleeds off boost. If anything it seems a lighter spring may help the situation if you start bleeding off boost sooner. This may take some experimentation to get it right. Too light and you loose too much boost. Just a thought.

I don't recall the specifics around Wayne at Callaway saying to use a stiffer spring for bleeding off boost so I'm unsure if something is being misinterpreted. I do agree that a call could not do any harm and maybe provide an answer.

 

[turbocat]

search "boost creep" on the net -google or yahoo if you guys really want to know whats going on.

 

[90Callaway]

My other thought was porting the wastegate housing. It would not be reversible to stock however it would appear stock. Is that a possibility? I don't know what limitations there are with the housing.

 

[*89x2*]

My other thought was porting the wastegate housing. It would not be reversible to stock however it would appear stock. Is that a possibility? I don't know what limitations there are with the housing.

Kevin, Thanks for chiming in - this may have been part of the conversation as well (in front of the work bench) - it does seem that porting (to keep the wastegate efficient to flow) has cured this problem w/ boost

 

[Bluewasp]

re-installed stock exhaust and mufflers,went to road test-no boost creep. Went back to arcives at this site and found that others have had over -boost problems when cats or exhaust was changed. Since no one wants to believe what I have to say -this will be my last post-bye.

'

Dude, Drop the crack pipe and step away!!! I don't see any post about "No one wants to believe me" ????? Maybe your free flowing exhaust fumes went to your head??

I would suggest you take the advice that members of this board offered and call Callaway. I doubt they are feeding you BS, and I would think since they offered a solution to your problem that they believe you have it. Also if someone at Callaway suggested a different spring to solve the problem I would think it would solve it.... I would suggest next time doing more research before getting all bent out of shape.

The only issue I see here is did you call Callaway... NO!

 

[turbocat]

This is why my posting days are over-some **CORVETTE LOVER** that doesen't know a turbo from a turb** wants to wade into the discusen. I KNOW WHAT THE PROBLEM IS- I JUST WANTED TO POST SO I COULD HELP OTHERS.THE WASTEGATE WON'T FLOW ENOUGH AIR.!!!

 

[Bluewasp]

This is why my posting days are over-some **CORVETTE LOVER** that doesen't know a turbo from a turb** wants to wade into the discusen. I KNOW WHAT THE PROBLEM IS- I JUST WANTED TO POST SO I COULD HELP OTHERS.THE WASTEGATE WON'T FLOW ENOUGH AIR.!!!

If you knew what the problem was and the solution to the problem then why did you post the problem as a question?

Again why don't you call callaway and find out what they say?
Are you afraid the different spring might work, and you might be wrong or are you just closed-minded?

Your posting days are over because you asked a question and someone gave you suggestion... ??? hmmm sounds kind of NUTTY to me!!!!!!!!!

 

[SurfnSun]

This whole thread has taken a dive.....

 

[Bluewasp]

This whole thread has taken a dive.....

 

[*89x2*]

Keep this thread on track - personal differences should be kept off liine (e mail)

 

[Rob]

After reading through this whole thread, I have a couple observations.

I don't see that turbocat was asking any questions. There are no question marks at the end of his sentences and his sentences aren't structured as questions, however, the context leads you to believe that he's looking for suggestions.

As a result, the other members stepped in with suggestions and it looks like turbocat didn't appreciate that.

That is however, unfortunate and I don't think it was fair for the other members to have received the response they got from turbocat. In my opinion they were only trying to help with what they perceived to be a request for suggestions.

Helping one another out is what these forums exist for. If yo don't appreciate the help that is being offered by the other members, simply say "thank you, I'm all set" and move on. There is no reason to flame anyone and I didn't see anyone flame turbocat.

Although Chris closed this thread, I'm going to go ahead and re-open. I think everyone has had an opportunity to calm down - Can we all just get along now - please?

 

[callaway4fun]

Turbocat

Turbocat when you changed the mufflers did you remove the Cats also? I found that removing the cats and putting on a custom 2 1/2inch true dual exhuast with an Xpipe I also found the elevated boost levels and also creep in the higher gears. I too am trying to combat this problem.