Accufab exhaust, tune, & pully warped my vents.


ROCK

GT Owner
Jul 10, 2006
401
Miami
Could someone please post pics of actual warped vents ?
Rock
 

ThatPhilBrettGuy

GT Owner
May 9, 2007
391
London, UK.
I wrapped my Accufab Pipes, makes a huge difference. I'll try to take some pictures.
I'm thinking of doing this as well as I get mine fitted. I'd guess that it reduces the sound level in the cabin as well, with all the nice noise going where it should....straight out the back.
 

Heffner Performance

*Supporting Vendor*
Supporting Vendor
Feb 22, 2006
367
I hate to hear of this happening to anyone's car. Given the variety of cars and combinations that this has happened to I'd say that where and how the cars are driven are big factors. I have never installed an Accufab system but it doesn't look to me that it is especially close to the clamshell. On the initial car that our pulley / tune combination was developed and tested on we did take some exhaust temperature readings and found no significant differences between the tuned car and stock. Actually in most instances our EGT's were slightly cooler, even under wide open throttle which is not uncommon when you are running less fuel through the engine. When you run as rich as the factory tune does it can tend to burn some excess fuel in the exhaust system and catalytic converter which will yield significantly higher exhaust temperatures. Another though that comes to mind is the difference in cam timing from one engine to another. While experimenting with can timing on a car a few weeks back we noticed that advancing the exhaust cam would raise the exhaust temperature by as much as ~200 degrees. There is some possibility that there is enough variation in cam timing between two cars to cause this. Replacing the vents with a more durable material is great but it would be nice to nail down a common thread between cars that are having this issue and actually identify a cause.
 

B O N Y

MODERATOR & FGT OWNER
Mark IV Lifetime
Sep 5, 2005
12,110
Fresno, Ca.
My first mod was the Heffner tune and pulley with the accufab which was done at the Wixsom rally. Then went to the Whipple with the accufab exhaust and now running Shadowman headers with short cats.
My vents are fine!


But Kip.... Need cf replacements... Pls Kip, pretty please :)
 

427Aggie

GT Owner
Mark IV Lifetime
Aug 18, 2005
885
Frisco, Tx
Oh I like the CAM solution..now maybe I can get Ford to pull the engine and degree the cams under warranty since they didn't seem to want to do it when they built the motors.

Its been discussed many times at the rally with the builders of the motors that they weren't allowed to degree our CAMs in which is believed to be the cause of such huge differences in HP on the motors from the factors...some are just right some are within spec but don't get the umph.

I'm just kidding..like I'm letting anyone pull the motor...sheeze
 

SteveA

GT Owner/B.O.D
Mark IV Lifetime
Dec 13, 2005
3,686
Sandpoint Id
I have a MMP pipe and Dyno tune and all was fine until about 3000 miles. Now I"ve got some droop. Todd is completely bone stock and the dealer just installed his new set of vents last month (7000mi). A friend has had a Borla with a pulley, tune and no cats drives VERY hard and his are OK (6000mi.). Go figure:confused!
 
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DBK

The Favor Factory™
Staff member
Le Mans 2010 Supporter
Jul 30, 2005
14,924
Metro Detroit
A friend has had a Borla with a pulley, tune and no cats drives VERY hard and his are OK (6000mi.). Go figure:confused!

That's what I'm sayin. I have the Heffner Exhaust, pulley and tune and I think I'm probably near the top of hard drivers and with 8000 miles mine remain fine.
 

Neilda

GT Owner
Oct 19, 2005
3,559
London, UK
I have the Ford Racing Parts transaxle cooler and have not noticed any additional heat. I'm not sure the radiator runs that hot does it?

Why not stick some heat tags in the area and we could take a look...
 
Aug 25, 2006
4,436
I have watched this thread continue to get legs and at the end of the day would a set of aluminum vents or carbon fiber be nice; absolutely. Having shared this I would be sooner drawn to the aluminum because I have no other carbon fiber as such I feel that it may be a bit of a bulls-eye on my gal however for example on Bony's gal with the cool carbon fiber air inlet ducts they would tie in very nicely.

With this being said the question of the day seems to be why some and not others irrespective of the exhaust installed, whether the clamshell is opened after returning from a run, etc. warp.

I wish to offer another plausible explanation; considering that the clamshell's expansion characteristics are much different from the inserted plastic trim pieces I think that there is a possibility that the manner in which they were secured could be playing a roll. Meaning; are the nuts too tight on some or worst the insertion holes not placed in such a way that a modicum of expansion and contraction can take place as they heat and cool as such the part simply becomes stressed while heated and then bows/warps as the byproduct of the installation having less to do with the physical characteristics of the vents.

I can share that all of my vent nuts were only finger snug and a few were actually loose and I have no warped vents. Furthermore I left them this way and because of a recommendation from another did "NOT" use Locktite but rather placed a very small dap of silicon on the threads after the nut just so it/they cannot freely come off and yet they remain fully serviceable.

Takes care

Shadowman
 

SteveA

GT Owner/B.O.D
Mark IV Lifetime
Dec 13, 2005
3,686
Sandpoint Id
My car goes in for a replacement set on tues. The plan is to remove them when I get home and replace them with the warpped set for everyday use. It would be very cool if one of these aftermarket options goes into production and I could just junk the bad set.
 

richardhead

GT Owner
Sep 19, 2006
169
Hello All-

Richardhead - ceramic coatings do reduce temps. Even more if you the interior of the pipes are coated rather than just the outside.


Sorry I wasn't clear....I just assumed everyone always ceramic coats both inside and outside. The cost just isn't that much more...if any on some jobs.
 

Kip Ewing

CF Vendor
Mark II Lifetime
Feb 23, 2007
288
Suburban Detroit
vents in carbon?

Anyone up for vents in carbon?

I had planned to get to this one, eventually, but it looks like there is immediate need.

It would be pretty tough to do a carbon version of the original louvered vent.

My intent has been to do something in the spirit of the flat panel with the oval slots some of the original race cars had.

Interested parties PM me and I can start planning.

Oh yah, get ready to see something cool for the car's instruments sometime next week...
 

kosupply

GT Owner/Board of Directors
Mark IV Lifetime
Jan 27, 2006
236
Houston
Chip,

Some very interesting observations. I believe that the primary factory at play here is the physical location of the exhaust and tube bends (heat concentration points) of the Accufab. I believe that this is much more a factor than the pulley/tune. Unless you are driving aggressively, the car will operate at 14.7:1 a/f ratio - regardless of tune or OEM set-up. The Heffner (like most tunes) will run leaner and higher HP in open-loop (aggresive driving) mode but will quickly settle down to closed-loop 14.7:1 as soon as you are "off of it". Your around town, stop and go city driving will closed loop and 14.7:1 (unchanged from OEM set-up). I guess what I'm saying is that the Heffner tune/pulley will in fact produce higher temps and more HP but this is typically and higher road speeds with more airflow in and around the exhaust. I think that your highest under hood air temps occur in "normal" driving - especially in stop & go with high ambient temperatures. As such, you pulley/tune are not in play - but the physical properties of your exhaust is still a contributing factor.

I am on my 3rd set of vents with 9100 miles. My first set were warped at 2000 miles....stock car at that point. I was tracking the car some and saw 220 degree temps. Because of the slope of the clam shell, the lowest point of the vents is above the exhaust. I now have the Heffner , Hennessey pulley and tune, quit tracking the car, and the vents on the car have not warped for the last 3000 miles.
 

gtkurt

GT Owner
Mark IV Lifetime
Nov 25, 2006
84
Scottsdale, Arizona
Chip
Mine warped with in three months bone stock. I received my GT last July brand new. I am in Scottsdale as well. My car is far from stock now does not seem any better or worse. 5 star Ford replaced my vents under warranty about 3 weeks ago.They gave me no hassle what so ever. In fact they treat me like royalty. I would suggest you get with them to fix your warpage issue.Please feel free to contact me if i can do any thing to help. Kurt
 

AZGT

GT Owner
Mark IV Lifetime
Dec 20, 2005
1,349
Scottsdale, AZ.
I'm no expert but perhaps metal (aluminum, stainless, etc) isn't the solution. Metal obviously has different thermal characteristics than plastic and if a metal vent really heats up it might not warp but it might get hot enough to damage the surrounding paint. I would think another composite product would be the answer but I can't say for certain. Thoughts?

We'll see.

I have top and side metal replacements in the works (prototypes).

I had already thought about heat, expansion, etc.

If they work, I will check them with the infared thermometer and see if they have any more heat than surrounding areas.
 

Ed Sims

GT Owner
Mark IV Lifetime
Apr 7, 2006
7,569
NorCal
carbon fiber

Kip - Can't wait to see what you have for us next!

Shesgotlegs - The CP car Millen is using had the CF engine shell liner of a standard weave while our GTs have a less expensive CF. They are a mixed/loose fiber but not painted. It is CF but almost could pass as plastic. Is this right Kip?

Ed
 

shesgotlegs

GT Owner
Mark II Lifetime
Jul 20, 2006
1,138
"He also did a cool air mod by blocking the engine bay air inlets and removing inner clamshell baffles. 100% cool air intake. Installed "

What is the story on having the screen there, was there an air flow issue of some kind the air box or MAF did not like?

Are the balles behind the screen or in the air box?

What is the downside of blocking these?
At the rally Steve Stillen mentioned that his GT race car at one time had problems at very low speed whereby the engine would stall when being moved around the lot - something to do with cross wind / air pressure change. It was determined that his very early car didn't come with baffles from Ford but definetly needed them.

On another note if anyone noticed, his clam shell underside was finished in carbon fibre and not painted black carbon fibre like our cars. He said it was because Ford didn't want anyone potentially complaining about imperfect looking carbon fibre.Too bad.
 

AZGT

GT Owner
Mark IV Lifetime
Dec 20, 2005
1,349
Scottsdale, AZ.
I have the Ford Racing Parts transaxle cooler and have not noticed any additional heat. I'm not sure the radiator runs that hot does it?
I was thinking as more of an air flow restriction rather than added heat. Since there are the two side vents and you somewhat close up one with the cooler, I was just wondering.


I think that there is a possibility that the manner in which they were secured could be playing a roll. Meaning; are the nuts too tight on some or worst the insertion holes not placed in such a way that a modicum of expansion and contraction can take place as they heat and cool as such the part simply becomes stressed while heated and then bows/warps as the byproduct of the installation having less to do with the physical characteristics of the vents.

I can share that all of my vent nuts were only finger snug and a few were actually loose and I have no warped vents.
Wondered the same. I had mine off soon after I purchased it to do some cleaning (18 months ago), and naturally tightened them when I put them back on. When I took the vents off the other day I was surprised how loose the nuts were. Do they loosen and then warp? Maybe they need to be snug so that the entire vent is secure against the clamshell. Don't know, but we do seem to have a warp / no warp variability going, so we need to look for inconsistencies between the two gtroups.
 

Kip Ewing

CF Vendor
Mark II Lifetime
Feb 23, 2007
288
Suburban Detroit
Carbon

Greetings Ed

The car that Millen has is a very early car. Not sure what the number was.
A very few of the early development cars had inner clamshells that were from a 2x2 twill weave carbon. The regular production cars used a unidirectional fiber carbon. I can't recall why we went that way in production. That would be one for Bill Clarke to answer. Usually the reason is to use the fibers most efficiently for a given load path. It doesn't look as cool, though... The Z06 fender is a unidirectional fiber, but it is painted.
 

Jazz76

GT Owner
Mark IV Lifetime
Apr 9, 2006
27
Harleysville, PA
I had Bob Ida installed his exhaust system and had them wrapped. One thing I noticed is that his system was angled toward the rear grill away from the air box and vent. He also did a cool air mod by blocking the engine bay air inlets and removing inner clamshell baffles. 100% cool air intake. Installed Wipple. No warped vents, but a lot of burnt rubber on my 300' driveway.

Hubert