38mm wastegate enough? - Ford Mustang Forums : Corral.net Mustang Forum
 
LinkBack Thread Tools Display Modes
post #1 of 11 Old 04-03-2007, 02:22 AM Thread Starter
Registered User
 
Trader Feedback: (30)
Join Date: Jul 2005
Location: Bellflower, CA
Posts: 1,154
38mm wastegate enough?

I haven't started my car yet, so I want everything to be good before I need to start tearing #### out. So with that said, I'm running a 306, TFS heads, TFS Track Heat manifold, stock cam, 1.7rockers, B&G Turbo Headers, Precision PT-67 P-trim .68 a/r. I'm shooting for 475-500rwhp anywhere from 10-15psi, whatever it takes. Will my Tial 38mm wastegate be enough to fight off boost creep? Or should I get ahold of at least a 44mm unit?


-'90 Mustang LX Coupe 5.0 SSP. 83 DSO US Gov't Issue. H/C/I Track toy
93Krwy is offline  
Sponsored Links
Advertisement
 
post #2 of 11 Old 04-03-2007, 10:35 AM
Turbo Wizard
 
snipe656's Avatar
 
Trader Feedback: (1)
Join Date: Jul 2001
Location: Houston, Tx, USA
Posts: 4,289
It should be enough but can greatly depend on the design of the system. For example a 38mm is enough for a PTK kit but put it on an HP kit with a similar sized turbo and boost setting and experience boost creep.


--Admiral Aaron

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
snipe656 is offline  
post #3 of 11 Old 04-03-2007, 07:41 PM
Registered User
 
rdub79's Avatar
 
Trader Feedback: (80)
Join Date: Aug 2005
Location: Clermont, Florida
Posts: 1,652
I don't think you'll have a problem with it, try it and see.

Is your your WG vented back into the downpipe or to the atmosphere? I've read somewhere that an "undersized" wastegate is more prone to boost creep if vented back into the exhaust, and not so much if its vent to atmosphere.

I haven't got mine running yet, but will be using the same TiAL 38mm wastegate with my turbo kit (B&G hotside,3" custom coldside,MP T-70) I think it'll be enough.

88' Coupe
rdub79 is offline  
Sponsored Links
Advertisement
 
post #4 of 11 Old 04-03-2007, 08:21 PM
Registered User
 
Trader Feedback: (0)
Join Date: Jul 2004
Location: San Diego
Posts: 1,006
I run a T-70 with only 7psi with no creep. You just have to put it in a good spot so it can work correctly. Vented into the atmosphere also helps.
10secgoal is offline  
post #5 of 11 Old 04-03-2007, 10:07 PM Thread Starter
Registered User
 
Trader Feedback: (30)
Join Date: Jul 2005
Location: Bellflower, CA
Posts: 1,154
It'll be dumped back into the downpipe. Right now it sits in a bad spot, on the crossover, maybe 9" below the turbo. I'm moving it where the passenger header and tube for the crossover meet just under the flange of the turbo, and dump that back into the wastegate. If it was a track car, I'd run it towards the ground, but it's not, so I wanna keep it kinda quiet.

-'90 Mustang LX Coupe 5.0 SSP. 83 DSO US Gov't Issue. H/C/I Track toy
93Krwy is offline  
post #6 of 11 Old 04-05-2007, 12:48 PM
Registered User
 
Trader Feedback: (5)
Join Date: Sep 2005
Location: NC
Posts: 89
My WG dumps back into the exhaust. Brian (B&G) told me that I would get boost creep ( 9 psi regardless of spring ) by it dumping back into the exhaust.
L&StangNC is offline  
post #7 of 11 Old 04-05-2007, 12:54 PM
Turbo Wizard
 
snipe656's Avatar
 
Trader Feedback: (1)
Join Date: Jul 2001
Location: Houston, Tx, USA
Posts: 4,289
Then it is not designed correctly. Seems pretty simple to me, you can find other kits designed differently with the same sized gate and turbo that does not experience creep. For example, PTK kit dumps back into the exhaust and I have seen them with T7x turbos and 35mm wastegates and have no creeping issue.

--Admiral Aaron

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
snipe656 is offline  
post #8 of 11 Old 04-05-2007, 09:52 PM Thread Starter
Registered User
 
Trader Feedback: (30)
Join Date: Jul 2005
Location: Bellflower, CA
Posts: 1,154
I'm def going to change the position of the wastegate, I really don't like the spot it's in right now. I'm using a TownCar/CrownVic P/S & alt setup, so everything is on the driver side to help even the weight out. So with everything outta the way on the passenger side, I'm able to mount the wastegate at the merge of the one header and the crossover just under the turbo flange. I guess I'm gonna throw on a 44mm unit since I'm changing the position anyway. I don't wanna have to dig everything back out once it's in. I just wanna drive the car now. It's already been park for over a year

-'90 Mustang LX Coupe 5.0 SSP. 83 DSO US Gov't Issue. H/C/I Track toy
93Krwy is offline  
post #9 of 11 Old 04-06-2007, 10:14 AM
Registered User
 
flashbang's Avatar
 
Trader Feedback: (8)
Join Date: Nov 2003
Location: Margaret, Al
Posts: 269
Yeah, HP changed their wastegates to 44's after they started having problems with the 38's and boost creep. The kit I have was one of the first few that took advantage of that change. Although I also dumped mine back into the exhaust.

1992 FHP SSP Coupe
1988 AL SSP Coupe
2003 Redfire Cobra--SOLD
1995 Mustang GT Vert-331/60-1 turbo SOLD
flashbang is offline  
post #10 of 11 Old 04-06-2007, 10:21 AM
Turbo Wizard
 
snipe656's Avatar
 
Trader Feedback: (1)
Join Date: Jul 2001
Location: Houston, Tx, USA
Posts: 4,289
Quote:
Originally Posted by flashbang View Post
Yeah, HP changed their wastegates to 44's after they started having problems with the 38's and boost creep. The kit I have was one of the first few that took advantage of that change. Although I also dumped mine back into the exhaust.
Yeah but they blamed(on forums at least) the boost creep on faulty wastegates and said that is why they were doing the change which is a load of BS, the thing is just placed incorrectly.


--Admiral Aaron

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
snipe656 is offline  
post #11 of 11 Old 04-06-2007, 05:07 PM
Registered User
 
TurboJunky's Avatar
 
Trader Feedback: (7)
Join Date: Aug 2006
Location: Central NY
Posts: 536
My HP kit has the 38mm wg. I have noticed some boost creap when I was starting out with the kit. Now I have the boost set at 15#s and it does not move.
An interesting side note to this I will be stepping up this summer to a 351 and a t76gts turbo. My kit will only work with a 302 so I had to buy the 351 specific passenger side manifold and crossover tube. I was planning on just running two 38mm WGs because they are much cheaper than the big WGs. When I ordered my 351 specific pipes I mentioned that I wanted them to add a extra WG mount they said that I would be fine with the one 38mm WG. There reasoning was the higher boost levels I planned on running, 15 to 20#s. It will be interesting to see if they are right. If not I will have to weld on that nice shinny ceramic coated crossover pipe.

1979 Mustang coupe, EFI 393, A/A intercooled Eaton m122, 4r70w trans, Megasquirt II, T-top swapped in.

1990 Mustang, 545 BBF, C-4 with brake, ladder bars, tunnel ram with two Predator carbs, solid roller cam, 9", 390/45r15 drag radials.
TurboJunky is offline  
Sponsored Links
Advertisement
 
Reply

Bookmarks

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Ford Mustang Forums : Corral.net Mustang Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome