STUMPED: Mark 4 exhaust problem

[MN GTM GUY]

I had the exact same thing happen, but I would had to remove 2 3/4" on the drivers side. I went thru all the details with FF and what I had to do was slightly open up the holes of the mount brackets to allow the engine to drop more on the drivers side. It allowed the angle to minimize the cut, you still need to cut both sides, they are undersized from the factory but I was able to tilt the engine just a few degrees to get the angle a bit better. I went through everything you did and verified everything but in the end the only fix was to lower one side deeper into the fixed mount and boom I was done a short 6 hour fix, set the engine, lift it, open up the mount, lower, check, over and over... My car is at the painter or I would take some pictures but PMme if youwant my phone numberand we can talk it through. I only had to open up about 1 1/2" after this was all done, mostlyto keep the paint cool.

[michael everson]

I would like to see the pictures of that. 1.5 inches is a lot. Theres no reason you should have to tilt your engine to get the side pipes right. I would have had to tilt mine 5.5 degrees. This was after modifying the engine mounts, slotting the mount holes to move the mounts closer to the block, and cutting the body. BTW I dont think the trans mount will like a 5 degree tilt.

Mike

[evvander11]

I am also at this point of the build. The engine is in and headers are bolted on. When mounting the body for the first time the cutouts line up just as Mike's original photos. (small amount of shaving on the passenger side needed, 2-3+ inches on the drivers side) So when does this become more then just an unusual problem? It seems a handful of us now have the SAME issue regarding fitment.....the engine is level and I am not a huge fan of tilting the engine throwing the trans mount out of kilter by slotting the mount.

The driver's side needs a bit more clearance as well right? Due to the engine torquing that way?

[michael everson]

Evvamder11 contact Factory Five. They need to know that this is becoming a problem for some builders. Seems like there are several in this same situation right now.
Mike

[MN GTM GUY]

FF was the one that came up with this solution, if they say that this is new someone is not giving you the full story. My engine was much less then 5 degrees, it was so little that you can't even tell from the top and you can only see a bit of tilt when looking at the oil pan and yes the transmount will handle the tilt. The pipes are so long that just a slight tilt makes a big difference at the opening. The 1 1/2" I spoke of was the amount that I had to open the area around the pipes not the tilt. I'm surprised you painted the body before you tested the pipe fitment, how did you make sure that the opening was large enough to not cook the paint?

[michael everson]

I recieved the car already painted. I believe the initial body fit was done with shorty headers and J pipes. the 4 into 4 pipes were added to the build just before I took it over. If you look at my original pictures, you can see how perfect the passenger side is. That was with the engine level. once you start tilting the engine to fix the problem one one side, you just add it to the other side. I dont think thats the best long term solution.
Mike

[Dale Claytor]

I'm having the exact same problem. I have a 302 block, pro-comp heads and BBK headers. I've modified the motor mounts and moved the engine as far right as I can and tilted it slightly to the left. I managed to get about 3/4" more clearance on the drivers side with just a slight drop in height, but it's still way off. Also, my bell housing is now touching or I should say resting on the frame brace on the passenger side of the frame in the engine bay. I'm going to look at stock motor mounts and see if they are as thick as those provided by FFR. Also, I noticed that my drive shaft is no longer aligned with the trans and rear end, it's slightly off. Looks like I would have to modify the trans mount also if I leave the engine where it is now. So, I'm thinking of realigning the engine in the center of the frame, tilting the engine slightly to the left, and have the headers modified to take off some of the length on the passenger side. Any comments?

Dale

[Dale Claytor]

Just a quick update. . . I recentered the engine and it now clears the frame brace on the passenger side. I didn't think of it before, but I measured the length of the headers from the manifold flange to the collector flange. The drivers side measures 21 1/16 inches and the passenger side measures 19 1/4 inches. If the drivers side header was the same length as the passenger side, there would be plenty of clearance between the collector flange and the cut out on the body. Height may still be a problem though, but may be able to adjust that by tilting the engine a bit. Could someone measure a set of BBK headers on a Mark IV and let me know what you get? Thanks!

Dale

[CraigS]

This is beginning to sound like another FFR design or QC issue like the too short IRS axles . And the solution given to MN GTM GUY sounds like another cheap fix like the axle spacers. I am once again becoming concerned about the direction FFR is currently heading.

[Ringo]

I was going to order a kit in a couple of months. I still need to turn a wood shop into a car shop. After reading this I may not. Lots of companys lost good people because of the economy and do not have the workforce left to put out a good product. I hope this is not going on here.

[tirod]

I doubt F5 is having that problem. The lack of lawsuits and lawyers fees are likely noticeable on the bottom line, and even in this economy, they aren't on the brink of closing. Hopefully management understands it's not in their best interest to let experience people go just to make payroll for the rest. Those who do aren't staying in business long - and F5 is launching a new line. Really, folks, if they were hurting that bad, the 818 wouldn't even be a topic. It would still be on paper.

Fitting issues are common and normal. This isn't Legos. In this case, the actual cause of the difference hasn't been determined, but a lot of builders have come up with the answer. One so far - BBK isn't a supplier anymore. Another - this is a customer car, the header installer had no input on body fitment or where things would wind up.

Since this has come up, the question needs to be asked - why bolt down the body when header fitment and getting the engine aligned is ALSO part of it? The Coupe guys note it, too - sometimes the headers, engine, and body don't cooperate. It takes more than assuming it will, to make it happen. The build only has one manager of quality control, assembly, and aesthetics. When you choose to wear all the hats, you get all the responsibility.

Blaming someone else isn't a solution.

[michael everson]

I was going to reply to Tirod, but my instincts are telling me to let go.....

[Dale Claytor]

Well all I can say is I'm an owner builder, and I've controlled every aspect of the build except for what was fabricated by FFR. The headers don't fit, period. Blame? Nope, was just looking for solutions and some help. . .

[etrone76]

I just mounted my MK4 body on Saturday and had the same issue on the drivers side, passenger side looked great with minimal trimming and the drivers side looks like i need to take an additional 1 1/2 to 2" more than the factory cut out.

[Nelson jr]

Hi guys I had the same issue and I was told it was the first they heard of this issue. I checked mounts. I measured everything and it was all correct apparently they have an issue with the headers. I went ahead and cut the body approx one inch on the driver side. Once you install the side pipes u really can't tell besides you can see both sides at the same time

[Dale Claytor]

I wouldn't mind cutting the body a little more to make it fit, but the driver's side header flange is almost flush with the inside of the body. With engine centered on the frame and leveled, there's a 2 inch gap between the passenger side header flange and body and almost none on the drivers side. When exhaust pipe is bolted in place on the driver's side, the top of the flange actually rests against the inside of the body. Then there's a huge unsightly gap running the length of the exhaust pipe between the exhaust pipe and the body. The passenger side looks great. It's very noticeable. I found a welding shop that is willing to cut about 1 1/2 inches from the drivers side header and reweld the flange. We'll see how that works. I can correct the side to side difference that way, will work on height once it's done.

[CraigS]

If you shorten the header like that then some Breeze wedges between the header and the pipe will also help. I bet that when they weld on the flange they could also fudge it at a couple of degrees angle.

[Jeff Kleiner]

...I measured the length of the headers from the manifold flange to the collector flange. The drivers side measures 21 1/16 inches and the passenger side measures 19 1/4 inches.

By design the engine is offset to the right hence the different length side to side. The Hookers on my Mk3 measure approximately the same as what you report. The Mk4 I built with BBKs is with it's owner so I can't measure it but I can report that the fit was right on and the only adjustment required was opening up the collector holes to allow leveling of the sidepipes front to rear.

As I said in this thread a few months ago, when Everson runs into a problem like this it is definitely NOT a builder issue.

...BBK isn't a supplier anymore...

News to me. Care to elaborate?

Jeff

[Dale Claytor]

Thanks Craig! Good advice! I will have the welder angle the flange.

Dale

[Zaphod]

I'm surprised that a F5 rep has not popped in to comment on this issue. As a potential buyer this is the kind of thing that may well scare me off. If there is something unique about the various builders' configurations that are causing the issue, the F5 should be working to identify the potential causes. If it's caused by poor subcontractor QC, or a design flaw, F5 should be on the boards explaining it.

But the silence is puzzling and does not reflect well on the company.

[tirod]

Joe and Olli. FFR no longer makes these. They are made by BBK. Jason said they have made 600 sets with no issues. I did not personally see the side by side comparison, but I know Jason knows what he is doing.

Olli the headers are new but have been run in gokart stage
Mike

My bad, misremembered the quote. I'm corrected.

As for fit and finish issues, again, it's not Lego. Reading posts over the last year, there are two different views - "The kit should be perfect and have none!", or, "It's a kit, deal with it like I did." I tend to side with the latter as a more realistic view of life.

What the mechanical cause of the misalignment still needs to be sorted out. That will be more productive at this point, directly and as a heads up for the rest of us. So far, it could be the chassis mounts, the motor mounts, the headers, the body cut outs, - or a combination. The heads don't seem to be in question, although that manufacturer offers two different exhaust port locations, and it's only assumed they were a matched pair. Same for the header plates, did BBK mix them up? .125" is a lot extended out to the fenders.

Having worked in a truck plant making body parts, I'm aware of tolerance stack issues - too many things on the edge of allowances become a conflict, which is obvious here. Even made and QC'd to spec, it happens. Since F5 cannot control what parts get used for the final product, it's just a bit much to see them having to suck up the blame when it hasn't been narrowed down.

I see the same things on the AR15 forums, everyone likes to say it's like building with Legos, but no, it's not. There are always a some builds with parts that simply don't work together, finesse has to be exercised. Some just send them back to CS with an explanation or phone call. They do their best, but they can't one - off a special part to match some other makers' final installed dimension.

It's no fun having to deal with fixing something when there is no choice in what was purchased and put together - I won't do that work. It's a job for a thicker skinned individual with an appetite for challenge and the confidence to make it work, and get 'er done quickly.

What's the fix for this?

[Zaphod]

Tirod, I work for a company that manufactures aircraft for the defense department and I'm familiar with tolerance build-up. In this case, between the chassis, body and headers, there aren't that many variables to stack. And what there are should not add up to the gross misfit seen by Mike. And should not require a significant realignment of the engine to fix.

Sure, it's not Legos, but the positioning of the engine in the chassis and resultant header location should be a given.

JMHO, worth every bit of 2 cents. And I can understand about fiberglass bodies needing a fair share of TLC to get right, and other minor issues like panel alignment.

[MPTech]

I still think that the root cause needs to be identified before any more blame is directed at FFR.
Sounds like they have attempted to address it, but they can't fix what they don't know yet and they are trying.

There are 600+ (quoting someone earlier in the post that said over 600 sets of headers) that fit just fine, so statistically this accounts for a problem of about 1%(?).

It's not fair to compare to the IRS or coil-over shocks issues, which are pointing to everyone experiencing the problem and they have a root-cause identified.

Good Luck, this seems to be a challenge to resolve, but I wouldn't let it influence your decision to but an FFR, it will get resolved one way or the other.

[Dale Claytor]

Just for info, I sent an email yesterday to FFR Tech explaining the problems I'm having. Am waiting on a reply.

Dale

[michael everson]

I still have access to the car that started this thread if anyone would like to look at it and get measurements. This was not a stack up of tolerances. After lowering my engine mounts and unleveling the engine etc., I was still a full 2 inches too high on the driver side. There was no adjustments or body cutting that would fix this.

Mike

[Avalanche325]

I am interested in this thread since I have a MKIV with 4 into 4 headers. What I don't understand is that some measuring should pinpoint the problem. After all of this time, there has to be a measurment that is off.

I had an issue with not being able to center a Wilwood rear caliper. An hour of measuring every piece and I found that the holes in one caliper were off center. A new one is on the way.

Are the frame rails level?
Are the motor mount perches level?
Are the perches at the same angle?
Are the motor mounts good? I remember reading that the factory Mustang convertible mounts drop the engine lower than the coupe mounts. Would that help?
Are the ports on the heads at the right height?
Are the headers good? Length and espicially angle.
Is the body crooked?

There has got to be something that is the problem. It can't be a case of everything measures up and it doesn't fit. Tolerance stacking on a couple components is not going to add up to 2 inches.

Honestly it sounds like custom motor mounts would be a quick solution. But I also like to find the root cause before doing a workaround.

Just a thought: What about lopping off a motor mount perch, adjusting and rewelding? Provided you are not powder coated. Expierienced welder required.

Please keep this going until the solution is found. You could be helping several people out.

[Dale Claytor]

Well, I had 1 1/2 inches cut out of the driver side header which corrected my side to side problem. With the engine centered in the frame, I now have just about 2 inches from header flange to inside of body cut out on both driver and passenger sides. By tilting the engine slightly to the driver side and using a Breeze Automotive angled spacer, and hours of tweeking, I was able to get the exhaust pipes on both sides running parallel to the body with about an inch space between the body and the pipes. The height of the pipes on either side are within about an inch of each other. However, because I shortened the driver side header, I had to cut out another inch of the exhaust body cut out. The total cost of the header mod and the spacer was $120 and several hours of tweeking. I still haven't received any kind of response to my email to FFR Tech, hmmm. . . On a positive note, my mock up is complete with exception of mirrors, wipers and bumpers and my wife and I took our first drive yesterday afternoon. All I can say is woo hoo

[archerz12]

Michael

As some of you know I have been trying to fix this problem for some time. I have a customers car that refuses to allow me to bolt on the driver side side pipe.
Here are some pictures of the problem. I took the Header to Factory five and it was checked out and matches there master perfectly. I levelled the engine and made sure it was all the way down on its mounts. The passenger side seems a little high but I was able to get it on. The dirivers side, Forget it. I even checked the angle of the mouting surface on the heads and both sides of the engine are right at 75 degrees. The header is sitting flush against the head as evidenced by equal and complete crushing of the header gasket.
I am out of ideas. Anybody have any advice for me? Alsmost 30 Roadsters, and I have never run into this before.

Here is a picture of the drivers side opening from a couple fo different angles


This is looking pretty much straight up the tubes


This picture is taken perpendicular to the body


This is from the back side


And here is the passenger side for comparison

BTW the engine is a rebuilt 5.0 with AFR heads. Energy suspension motor mounts.

[archerz12]

Michael,
I had this problem years ago with another remod project I was doing. What I had to do was make a template of the exhaust flange and take it to a machine shop. They made a special plate tapered from top to bottom with the correct angle. I had to modify the header bolt holes to compensate, but you really do not have that much of an angle differential. I used an exhaust gasket against the head and red high temp silicone between the plate and header. It worked. Good luck.

[Dale Claytor]

Hey Guys,

Again just for info, I sent an email to FFR Tech on 8/30/2012 outlining my problem with the centering of the engine in the frame and header fitment, I haven't received a reply to date. See posts above. . .

Dale

[jlfernan]

Hey Guys,

Again just for info, I sent an email to FFR Tech on 8/30/2012 outlining my problem with the centering of the engine in the frame and header fitment, I haven't received a reply to date. See posts above. . .

Dale

You're better off calling them. They have had a history of not returning emails.

[FMJ]

I've got the same issue...driver side header high and long. Can anyone tell me what Factory Five had to say?

-Fred

[OVCobra]

Unfortunately this is not a new problem (search the forum) and it appears to be a problem with the original design so checking against another header will not show anything. With the motor leveled, the driver's side header is elevated an extra 7 degrees vs. passenger side. The best solution I have seen was to wedge cut the pipes on the header and drop it accordingly. I just could not bring myself to do this to brand new ceramic coated header so I weenied out and fabbed a 7 degree wedge plate that fits between the head and header flange...everything fit great. I am probably going to have header leaks (not on the road just yet) but trying this out before more dramatic action.

FFR and others suggested shifting the motor on its mounts (off level) lowering the drivers side and raising the passenger side...will then have to cut body on both sides.

[FMJ]

Talked with Factory Five and was informed its an engine issue. The heads are off by a degree or two and that translates to multiple inches at the end of the header. This might not be my area of expertise but I'm not buying it.

My options are limited based on where I am with the build (almost done) and think my best option might be to contact these folks.

http://www.stainlessheaders.com

Anyone want to buy a pair of slightly used small block BBK headers?

-Fred

[Dale Claytor]

That still doesn't account for the header flange on the drivers side almost touching the body and two inches or more of space between the header flange and body on the passenger side as was my case. There's something else going on. My engine is definitely not positioned properly on the frame. I suspect there is a problem with the position of the motor mounts on the frame. Maybe the guys building the frames have bad days from time to time. There's enough roadsters having the same problem that maybe Factory Five should take a serious look at it.

Dale

[jimgood]

Talked with Factory Five and was informed its an engine issue. The heads are off by a degree or two and that translates to multiple inches at the end of the header. This might not be my area of expertise but I'm not buying it.

-Fred

If that were the case, wouldn't you also have a problem with intakes fitting? I'm sure it's possible but that indicates to me that all of the guys with this issue will also have issues fitting their intakes, won't they (see Ski Bum Vince's Mass-Flo stuttering thread on the other forum)?

It seems to me their template could be wrong. Their manufacturing processes have changed in the last few years. Isn't there a chance that the frame they used for their prototype was different enough from current frames that the template is no longer accurate.

Is it possible to buy just the flanges at each end of the headers? If it were me, I would bolt the flanges on to the sidepipes and the engine, position the sidepipes where they should be, then cut some stock to join the engine side and exhaust side together and tack weld them. Then compare the result to their headers and see just how far off they are. That should be less than a day's worth of work (probably a couple hours for someone competent). That could then be passed around to everyone having this problem to see just how many would benefit from the "corrected" positioning. Yeah, I know. I'm asking a lot. Just throwing ideas out there.

Just seems to me that the answer should not be that you have to clock your engine, use angled flanges or cut your body to fix a header positioning problem.

[edwardb]

This issue intrigues me. Clearly there is something going on for some builders. But not all. The challenge is figuring out why some and not others. My personal opinion is that it's probably not one thing. But the huge variations (multiple inches) is hard to understand. I agree completely with the point from FFR that something being off only slightly (a degree or two) translates into big differences at the end of the header and even further down the line with the side pipes up/down, in/out, etc. I'm not sure about the engine itself being off though. I agree with jimgood on this one. Then you may see some issues with the intake. Engine blocks are coming off some pretty serious CNC machine centers. Just don't see them being off a degree or more. I think the same could be said for most heads, OEM or aftermarket. Some of the possible variations, and thoughts about each:

Chassis engine mounts: If you've seen the chassis welding fixture at FFR (it's a beast) multiple key parts are clamped to a fixed location on the fixture, and then the whole thing is welded up in multiple steps. The motor mounts are one of them. In theory, there should be little/no variability with their location. But as we all know, metal can move around when welded. Technique does play into it. But still it's hard to imagine one chassis being so much different than another built off the same exact fixture.

Headers: FFR doesn't make them. The 302 SBF headers come from BBK. The 351 SBF headers used to come from Hooker, as did the big block headers. Don't know if they still do, and don't know about other engines e.g. mod motors. But like so many parts from FFR, the quality (or perception of quality) is totally dependent upon their suppliers. Which of course FFR has responsibility for. Not discounting that. In these cases as well the manufacturing process I suspect is fully fixtured and shouldn't have a lot of variability. I've personally bought two sets of the BBK headers. They seemed to be very high quality, and mounted up OK. I personally haven't had experience with the Hooker headers, but have read some reports of some quality concerns. Clearly some have solved this whole issue by having custom headers made. Good solution although not cheap. But this doesn't mean the headers were the actual problem. Only that the custom headers were fabricated in a way that resolved any alignment issues. One other comment regarding headers: Since the engine is not centered in the chassis (it's an inch or two towards the PS) the headers are not the same length. Some comments have suggested the different angles of each header is an indication of a problem. Actually, may not be. Given the different lengths, they're going to be different from side-to-side going to the same exit point on the body.

Engine mounts: Some guys use the stock mounts. Some (many I think) use the Energy aftermarket mounts. Others use solid or custom mounts. Could be one of the big issues, I suppose, but many report using the same mounts (e.g. Energy) and some have an issue others don't. Although there is some possible variation how these get bolted to the block, most (including me) drop the engine in with the bolts loose. Won't go in any other way. Then they're tightened wherever the engine falls into place. Just not sure we have enough information to think engine mounts are the problem.

Engine installation: Here, in my opinion, is the biggest area of possible variation. Having installed the engine in my Mk3 multiple times and in my Mk4 only once (so far, hope to keep it that way at least for awhile) I along with others have personally experienced that (1) it takes some pushing and pulling to get it to drop in, and (2) when it does, it wedges in almost immediately, whether in proper alignment or not. Where it stops I think has big variability, and I personally suspect this is one of the main issues. At least with the smaller variations. Multiple inches I can't say. But certainly for the lessor ones. For both my Mk3 and Mk4, the first "drop" of the engine into the mounts didn't provide good alignment. But loosening and moving the engine and tightening again got it to where it needed to be. Again, small movements make a big difference. I'm not sure some appreciate this point as much as they should.

Slots in engine mount: The following is my experience with 302 blocks. I've seen others report the same thing, but I don't know if applies to all. What I learned with both of my builds (both 302 size SBF with Energy mounts) is that the slot on the PS chassis engine mount plate is too low. With the pin on the Energy engine mount tight against the top of the slot, the PS side of the engine was still too low. I raised this slot with a die grinder 3/16 of an inch or so, and it made a big difference for header alignment on both builds.

Summary statement? For me it's still inconclusive. Like so many aspects of these builds, the combination of parts used is almost infinitely variable and how part differences and tolerances stack up is impossible to predict. FFR can't possibly account for each. Some custom fitting is going to be required in many cases. Add to that how small variations equal big differences in this case, and the problem is magnified. So some work to get proper alignment is a normal part of the build IMO, including the famous wedges, racking the engine around a bit, etc. But for me this shouldn't be lumped into the same category as those who experience major differences, e.g. inches. This situation is still a mystery IMO.

[FMJ]

IMG_1346.jpg

Looking how the motor sits in the motor mounts, its the same on both sides, I don't see anywhere to shift this thing. Notice the pin is at the very top. Again, its the same on both sides.

-Fred