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09-30-2020, 03:09 PM #1
Badcobra is back....1518whp / 1108tq
Been down for over a year, but we finally got the car up and running again. During the downtime, the engine was honed and freshened with some new pistons/rings/bearings. The cylinder heads were repaired from cam journal damage discovered on teardown and had some additional porting work done by Janderson Heads. The cam journals were damaged by a bent camshaft which I had straightened. Along with all of that, I bought some Precision 6870's from Tim Oswalt and sold my 6766's. The turbo kit was updated to fit the new turbos and I also had a new intercooler built utilizing twin Garrett 3" cores welded together.
I then brought the car to my tuner and he rewired the whole car and plumbed in a new vacuum system. Also put on a new strutless rear wing from Robert Carter amongst a whole host of other behind the scenes updates. We got the car running and on the dyno and made some pretty good power so I am really happy. I was plenty happy stopping at 1500ish wheel, although I believe it has over 1600 in it. Maybe try for that next year. Not bad for a baby cube 4.6
09-30-2020, 03:25 PM #2
09-30-2020, 06:30 PM #3
11-09-2020, 05:44 PM #4
Good power for sure and proof that the sky is the limit with the Teksid Ford MOD motor platform and thus I don't see the need to waste both time and money to swap over to a Coyote or some God awful LS if the goal is to make power in the triple digits with a 96-04 Mustang Cobra.
11-10-2020, 09:48 AM #5
- Join Date
- Feb 2006
Very Nice numbers! What did you have to do fix the cam journals. I didn't think there were alot of options there.
11-10-2020, 10:25 AM #6
The good part was we figured out why the journals were damaged, the bad part was my cam was bent and I had to get it repaired. We have a local guy who's been in business for 40+ years named Berry Cam Service who was able to fix it back to .001" runout and back in it went. I recommend anyone buying custom cams to have all checked before running them. Since this happened to me, I know of many people who have had a similar issue. I don't know how a cam can leave the factory like that, but it seems fairly common. I would have probably just replaced the head, but it was already ported and I didn't want to toss it.
11-10-2020, 12:40 PM #7
I have seen your 'new cam problem' and another on multiple occasions, Tony.
The bent cam problem is very much like the bent new crank problem. Sometimes the part is physically bent by an external force being applied and sometimes it is bent simply as the part relaxes after machining. The good news is the straightening process is well known and relatively straight forward although not intuitive.
The OEM clearance on the cam journal to head saddle is very tight at less than 0.001" so it does not take a lot of movement to put a drag on the cam. With a 1.0610" +/- 0.0005" Ford journal diameter spec and a less than 0.001" factory clearance finish fitment spec, it is real easy for a long camshaft to quickly get tight in its cam saddles.
Even when the cams are straight there can be a undesirable drag on the cam caused by the very close tolerances called out by Ford. This is a worksheet for a set of custom cams that were cut by a well known cam grinder that needed a lot of TLC before they would spin correctly in the heads;
As you can see the cam grinder had a problem maintaining consistent journal sizes. I have redacted the company name to protect their identity because the straightness problem could have happened in shipment. The Journal diameter problem however, is more because of unrealistically tight Ford specs and poor quality control on the cam manufacturer's part than anything else. The fix was to polish the cam journals down until I got between 0.001" and 0.0015" clearance on each journal. Once the clearances were where I wanted them, the cams spun easily with just my thumb and first index finger turning them by their nose journal.
The really maddening aspect of the modification/fix was temperature. When you are dealing in tenths of a thousandth the heat of the cam and the heat your body places into the micrometer as you are using it will change the readings. As a result the job gets very tedious very fast with maddening downtime periods as you wait for the cam to normalize back to the temperature it was at when you did the last journal. The micrometer is a little better if you have standards for it, so you can compensate for thermal expansion due to the heat from your hands holding it. Even so this job is long and tedious if you want to get it done correctly.
The journal diameter problem depending on who you talk to is either created by the cam grinder in finish grinding or the core supplier if the cores have finished journals. Interestingly I have never seen the problem on intake cams only on exhaust cams. Maybe someone is trying to compensate for wear in a used engine? Who knows — go figure. What I do know is if your exhaust cams are tight in their saddles you risk another "oiling failure" that will kill another set of cams and heads. The reason I went for the 0.0015" oil clearance instead of Ford's just under 0.001" spec was reliability and improved oiling.
BTW great info on the repair bearing inserts and the guys who can do the job.
Last edited by eschaider; 11-11-2020 at 01:35 PM. Reason: Fixed broken pic link