Cobalt, are you going back to Rick Deman? I saw his car at Lime Rock this past weekend and while the front hood was still on it, , it was one wickedly fast machine.

 

Yes,

I find Rick to be very knowledgable and straight forward. Although I have only been to his shop once he has impressed me more then any of the others in the area. Not only is Rick knowledgeable but his entire staff also.

He claims his car is producing 1000hp. I hear it is a real monster and he has the skills to handle it also.

 

Anthony,

I hear you, but I ran a solid 1 bar with the stock wastegate for 1 year. I use a separate boost guage and it truly was sold and stable at 1 bar, so I don't know why some cars won't hold it. My tuner did not see a need for anything. However, if there is an issue, the cost of a TiAL 46mm WG is only $460 and is a better solution for me than modifying the stock WG muffler. (Similar cost and better wastegate, right?)

Gordon

 

Gordon,

I do not know the flow characteristics of the HF turbo vs. the Garrett. It may be very possible that the HF pumps more air and can create problems that do not occur with the Garrett.

The people I have spoken to say that the stock WG is very capable and can handle engines producing upwards of 1000hp.

The problem with the HF turbo is that it is producing so much air that the cat restricts the ability to dump the extra flow, thus creating the creeping affect I am seeing on the chart. I could just go fo a fabspeed wg pipe that eliminates the cat and need for the 930 WG muffler. Or I could gut the WG cat. I just feel that the car becomes to obvious when they dump that air and make all that extra noise. I prefer to hear the rpms vs. the air being dumped.

I will post the charts when we are done.

 

I would choose a K27HF over a T04E frame Garrett. However, once you are looking for 500+hp, you will need to step up to a large frame Garrett T04S chassis.

 

Please do post results. I need to get this boost problem fixed. I have a bypass being made but it's going to take 2 weeks....

 

Guys,

I have a T36RS Garrett-based turbo with a 64mm stepped vane compressor. Significantly more flow than a K27 and more than many of the T04's. TPC has several cars with this turbo making 750rwhp.

Also, Cyntex insists that the stock WG will handle the 1 bar pressure without any issues and tells me its a waste of time to add the TiAL. We'll see how it goes. I'll post results, but they will not compare to te DynoJet numbers I had before, since its the Mustang chassis dyno...

Gordon

 

I have to agree, I don't think that HF is close to over loading the factory WG assuming the WG has no back pressure down stream. If I recall correctly, the HF is only good for about 500-550hp max... put a dump pipe on the WG and I think your problem will disappear.

 

Cobalt, are you going with the GHL and Fabspeed set-up? I finally got a little seat time last week in my car (althought the heat index was 108) and it sure was nice. not too loud, and the 4 inch oval tips look awesome.

 

Bogey1,

The B&B's are leaking more all the time and I am smelling what appears to be exhaust in the car under hard acceleration. The PO installed the B&B's only 1000 miles before I bought the car. They obviously leaked from day 1 and I think its why the PO sold the car.

If I have to pay to repair the B&B's I may just go with the GHL's and start fresh. I hear B&B makes you send the entire exhaust back for review before they let you know what they are going to do. Since the receipt for the headers is through the shop that installed it, they may just tell me to go screw.

Its a 50/50 toss on how I am going to handle the cats. I would love to get rid of the heat and weight but don't need the hassels of dealing with the DMV.

When I get my act together and figure it out I will let you know.

 

FYI, this bloke I know, has a friend, who has a brother-in-law in Texas that is not running cats and for the emmissions in Texas this guy removed the muffler and bolted on a single 964 cat and tail pipe and the car passed so clean it was better than most newer cars according to the shop that did the test so I was told by this er bloke and his er Brother-In-law.

 

OK, update on the overboost problem. After much money and time we have traced the problem to the GHL's wastegate pipe. It is actually quite small diameter 40mm, I think and can't flow enough gas. Other headers I have seen that don't give overboost problems are using 44-46mm wastegate pipes. The headers are off to be modified....

Here is a pic of the new wastegate that I accidentally purchased durring this episode..

 

Anthony,
What if you are still not able to fix the problem,no wonder the PO sold the car.Any way the easiest fix would be to just sell the car( to me ) & let me deal with all the headaches and you can have a fresh start with another 3.6 turbo with a stock exhaust.

 

Just to confirm the results of the work on James's 965, the overboost problem was indeed caused by the design of the GHL wastegate pipe. We worked through the problem methodically, first removing the motec wastegate controller, then the wastegate cat & fitted a straight through pipe, then the wastegate itself and finally the header to wastegate pipe. This final step resolved the problem completely.

It appears that there arte two issues with this pipe, the first is that it is only 1.5" bore and the second is that it is welded onto the header at approximately 95-100 degrees to the flow, so for the gas to exhaust through the wastegate it had to reverse in direction in order to flow down the pipe. We resolved the issue by fitting a 1.75" pipe.

Should anyone else be interested, our new wastegate as shown in the photo was fitted to the standard pipe with a 4 bolt adapter flange, but on the larger dump pipe we welded the mating flange directly it, thus fitting/removing the gate is just a matter of undoing the stanless steel clamp, no gaskets or bolts/studs to sieze! The photos show the clamp if you look closely enough. This wastegate is available with a choice of springs from £410 and for stock installations the 4 bolt stainless steel adapter is £60, which compares rather favourably to a new Porsche unit at £1100+.

 

I have an overboost problem as well. Here are the facts:

B&B header with dump pipe off stock K27 Turbo
Wastegate pipe is 1 5/8" diameter
Stock wastegate with very short (4" long) dump pipe

In 3rd and 4th gear at full throttle, my mechanical boost guage says I have one bar of boost. As the boost guage nudges past one bar I hit the fuel cut-off/overboost switch. This is strictly a track car. I am on the full boost for extended periods of time. I am trying to decide if I need to modify the wastegate pipe. I have to use the stock wastegate b/c I am building the car for D stock PCA Club Racing. Any Ideas?