New 347 Stroker Problems

Discussion in 'Fox 5.0 Mustang Tech' started by Chris Marlin, Aug 13, 2013.

  1. I have a old crate motor I bought years ago and put it in my 89 mustang. The company that built it is not around anymore and I am having problems. The motor has TFS heads and scorpion rockers. I topped it off with tfs intake a 65mm throttle and a Ford cobra kit(injectors,throttle). At this point just want a good driver not out to make a street racer. It has a custom cam made for the motor by them. I had a adjustable regulator on it untill I pulled it off after it would not stop leaking. Car runs but is not running right. Pops out of the exhaust and does not like low idle. Motor just does not sound right. I have fixed many little thing to get to this point as resetting dist. The lifters are very load also. I am thinking maybe they are not adjusted. I have a pair of short trick flow valve covers. MAybe they are hitting? I had them off before but saw no marks on the covers or rockers. But before I pull the top of the motor apart I just want to get some thought how to fix this.
  2. The TFS covers have a lot of clearance and clear just about all brands of rockers. I'd double check the valve lash that is a common issue with fresh motors...I'd relash it first. Make sure timing is 10-14 degrees fuel pressure 36-38psi with vac off.

    What's the entire combo? What maf sensor is on the car? Stock air box or cai? By cobra kit do you mean cobra computer, 24lb in and cobra 70mm maf?

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  3. sounds like you are running the stock computer and Cobra injectors which are 24#. What Mass Air meter? If stock, hen it's calibrated for stock 19# injectors.

    Give us those detals
  4. Sorry for the delay just got into the garage this weekend. The car ran better after the lifters bleed out over night. Rockers do need adjustment, No big. Also I am running the cobra computer with the injectors and mass air. One problem I see is the valve cover I pulled look like the right front rocker has been hitting it. Only on the top of the rocker towards the front. Anyone know a valve cover that will will work?
  5. What Rick said. But first do a compression test on it. My 347 did the same thing last time because some idiot had misadjusted a rocker and the valve wasn't closing. Compression on that cylinder came out at 5psi. Something like that is a dead giveaway.