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    1971 Mustang convertible


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    Los Angeles
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ianpala's Achievements


Explorer (4/14)

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  1. Well.... put her all back together and she ran super strong. And then she didn't. It's looking like either my lifter has collapsed or my cam lobe has gone flat on my Cylinder 4 exhaust valve for no good god damn reason. the rocker came loose twice and now I'm having to screw the nut all the way down practically to get 0 lash (adjustable valves with screw in studs). Only good sign is that the lifter doesn't seem to be pumping up bc when i press the pushrod down i can push the lifter spring down easily. If it turns out being the cam... I'm probably going to look into a rebuilt bottom end so i don't put in all that work on my original. Either way gotta pop back off the intake. This sucks
  2. So things I've learned.... 1) do not use coppercoat or any additional sealants when using newer Fel-pro head gaskets with permatorque coating. It caused leaks between almost all my cylinders in less than a year. 2) Fel-pro Printo-seal intake manifold gaskets SUCK. The seal around 3 out of my 8 intake ports failed. Each failure was due to a split along that blue "seal." This is an obvious weak spot. I have no idea why they would have failed. 3) Mr Gasket intake manifold gaskets aren't that great. Mine came out of the package with tears and they were essentially brittle cardboard. SCE gaskets are significantly higher in quality, really glad i ordered them, thanks Chuck! Hopefully will be firing her up today. Tuned the carb back to stock. Look forward to seeing if all my previous issues are resolved.
  3. Got them out with some torch to the pedestal! Does anyone have an intake manifold gasket they swear by? I got the same type (Fel-pro 1240) and am hoping with Don's torque specs and absence of Silicone they will do better this time. Also, looks like my head Gaskets were leaking between my cylinders which is kinda bananas bc they are only about a year and a half old. Hoping it was due to erroneously using copper coat on newer blue Fel-pro Permatorque head gaskets that ask for no additional sealers. Having the heads checked out by Burbank Speed and Machine to check for warping etc... Definitely looks like the intake gaskets were leaking due to the coloring of the corresponding combustion chambers. And looks like the rest were running rich due to that 4 size jump in the primaries! What a mess.
  4. Taking off the heads today. The intake manifold gasket looked cracked! Might have happen during removal though. Had some over heating and coolant loss so re-doing the head gaskets and taking the heads to a engine shop to make sure there are no cracks etc... BUT... Now I can’t get my screw in studs out to save my life. The guide plates block the head bolts. Have been trying the 2 bolt method and can’t get out a single stud. Any tips? Thinking of taking a torch to it to try to break it lose. Really don’t want to have to weld a nut to the studs. -Ian
  5. Going to order a fresh intake gasket and torque to your specs Don. Thanks Tommy, I'll try backing out my idle mix screws a half turn and see how that goes. the only rebuttal I may have to the idle circuit being too lean due to high vacuum is my idle vacuum is only 9-10 inches/mercury My throttle plates are almost fully closed, haven't needed to raise my idle speed at all. Do not have access to an extra 600cfm carb to test out. Honestly thinking of just buying another Quickfuel 600cfm, but want to turn over every stone before I do.
  6. The cam specs listed in the original post are the advertised specs. I've checked extensively for vacuum leaks with carb cleaner and plugging, so I'm confident there are none unless it's under the intake and figured it would have been done to damage during installation. I'm using an electronic distributor one of summit's. I'm also confident the idle screws are good they are around 1 1/2 turn adjusted with vacuum gauge in gear. I've had it set at 34 and 35 total timing, it made no difference to the problem described, was able to rule out timing as the issue. I can be coasting at 1700 rpm for 15 minutes and the problem will be consistent the entire time, then the second I hit around 2000 it smooths out (imagine this is when the secondaries kick in or potential vacuum leak plateaus?). honestly I could keep going up in primary jet sizes, but I've already jumped 4 sizes up, and I feel like I shouldn't have to do this and that it points towards an underlying problem. The only thing I haven't tried is what Don mentioned, adjusting the secondaries (maybe adjust them to open a little faster?). I also took it to a great mechanic here in LA and he couldn't figure it out either and double checked everything as well. He seems to think its the same thing, intake leak or defective carb. I just got of the phone with him and he to plug the PCV hole on the right valve cover and then feel over the breather hole on the back of the left valve cover, if I feel vacuum its an intake leak, there should be no vacuum or it should be pushing air out, so I'll try that. Unfortunately my breather grommet is pretty shot, so I'll have to wait until my new one comes in to really get a good read. ALSO: I remember there being a passage on the heads and intake in-between the 4 ports. My intake gaskets did not have a hole for this passage, so I cut one out in order for them to connect. Maybe this was supposed to stay blocked? or maybe it caused a tare upon installation. Just a thought
  7. I've taken apart and cleaned the carb a ton. I've shot brake cleaner through all the passages and none seem obstructed. It's definitely been running lean, I'll cruise for 5 minutes through out the trouble rpm range and shut off the engine, stop and then read the plugs and they either look new or barely white. Throttle plate is barely open, t-slot is good. I have not messed with the idle setting on the secondaries, I figured in this rpm range it would be all my primary circuit.
  8. Hey guys, Always like to start by thanking the community for its invaluable help and expertise, so thanks :) So... I haven't been able to figure out this issue since I put in my new cam and went from a 2bbl to a 4bbl carb. My engine struggles between around 1000 and 2000 RPM. Seems to clear up right at 2000 with an increase in power. Rough, chugging, low power, subtle misses. Pronounced when engine is cold or going uphill. Also a hesitation, if not a backfire out the carb upon initial acceleration, (the acceleration problem has been cleared up mostly with a red accelerator pump cam and jump from .33 to .35 pump nozzle). At first I thought this was all due to the primaries simply running lean (checked plugs after driving and shutting off engine and were white etc...) went from 68, to 70, to 72 primary jets... runs a little better but it is still there, so I think its something else. I've played with my timing everywhere between 10-13 initial and 33-35 total... seems to run its smoothest when its less advanced, but problem is always there, have it at 10 initial 33 total right now. My vacuum at idle is lower than I think it should be... its pulling like 9 or 10 inches of mercury. Also, the carb likes the 2 idle mixture screws at different depths. Checked everywhere for vacuum leaks, none found. Fuel pressure good, vacuum advance good and going to carb, problem still there if I run off manifold vacuum. AT THIS POINT I'm thinking I either have a vacuum leak on the underside of my intake manifold or a defective carb out the box. Is there anything else you guys can think of, or do you know of a way I can rule out the intake leak or isolate the problem etc? 351 2v. Quickfuel slayer 600, Edlebrock performer 2750 intake Comp Cam 32-242-4 .513/.520 262/270, Roller rockers AOD, posi, 3.70 or 3.72 rear gears (can't remember), Dual Exhaust Thanks again, this has been escaping me for about a year and its driving me CRAZY.
  9. The backfires were before I tuned the mixture screws and timed it, so I wouldn’t count that on the list of symptoms. And yeaaaa I've been thinking I oshould tear it down and put it back together to make sure, just been procrastinating since its my daily driver. Thanks
  10. So if I'm accelerating from a stop, or cruising real slowly, from 1000-1500 RPM it does what really seems to me is like a rich blurble and runs rough. (I'm going to pull some plugs to check color) Then at 1500 or shortly after it smooths out in one immediate moment with a boost of power. I'm not flooring it or anything, this is driving around the city. I'm getting awful gas milage, something like 7 mpg. It has also died while accelerating in this range when its cold, but only once. I will check the accelerator pump, and then the secondaries, never have adjusted secondaries. I'm going to replace my power valve regardless because I have had at least 3 to 4 carb backfires since installing, I know this can rupture the diaphragm and if I'm going to take it apart to check it i might as well put a new one in for $8. I will get one rated at half whatever my idle vacuum is. Thanks!
  11. Hey guys, went out of town for a little while but finally got back to the car and figured out the surging issue. It was a bad PCV valve. Should have figured it out, but it seemed to go in and out. got it timed precisely too. 12 degrees initial, 35 degrees total. My vacuum gauge method had it set somewhere like 30degrees initial :/. Ever since I've don't this work however, a new problem arose. from 1000-1500 RPM it runs like SHIT then its like a turbo kicks in and everything seems fine again. I'm thinking due to the new cam its running rich and I have to go down an inch or 2 in power valve size. My quick-fuel 600vs comes with a 6.5. Which isn't too far off but I'm thinking i need more like a 5. My vacuum gauge is acting up so I still haven't got a solid read but I thought my idle RPM is around 12-13 which should have been fine with that. Going to have to double check and also I'm going to drive around and get the read through those RPMS . There is also a chance i blew my diaphragm in it because I had a few carb back fires while dialing everything in. The problem just realllly seems like a power valve.
  12. Thanks guys. Right now I had the mixture screws set at 1.25 turns out each. I did this using my vaccine gauge. I took them between 1 and 2 turns before and there was no impact, however I did all of this in park while the surging is less noticeable. The idle screw is almost all the way out, barely had down to press down on the throttle bracket. My float levels are set at halfway up the viewer glass. I have my vacuum advance coming from manifold vacuum not ported from carb. Should I change that? Also I did clamp the vacuum advance hose before to see if had any affect and it didn’t. Also clamped all other vacuum hoses, and sprayed carb cleaner around the manifold which made me feel there were no vacuum leaks. I will check again. This Monday or Tuesday I will remove my carb and check my T slots to make sure they are kosher and also make sure my initial timing is right at 10 degrees to start before advancing (simply used my ear and vacuum gauge before). I will also re-do the carb settings initially while cold in drive when surging is at max. I just remembered having surging problems before the new cam, intake, heads and carb but I figured it was due to a flat cam lobe dropping the idle at that cylinder. The surging was not as severe which made me forget but it was definitely aparent here and there. I will do the discussed and get back. Thanks a ton.
  13. I have the Summit 850306 ready to run distributor(4 years old), a brand new QuickFuel slayer 600vs 4bbl carb and an msd flamethrower 2 coil(no idea how old). I had a loose coil wire for a while, don’t know if the intermittent connection could have damaged anything over time. Any tips on a quick way to isolate one or the other as the culprit? Like I said before, it clears up significantly once the car is fully warm.
  14. Thanks that will be helpful! Glad you think the vacuum sounds normal (between 14&15) I thought I should be closer to 20. Re-did the choke and mixture screws when it was hot. Didn’t change much. Will have to dial in the timing precisely when I get back into town. From fiddling with it before, I couldn’t get that surge to go away and 300-500 rpm seemed excessive, even when it’s not fully warm. Maybe I do just need to get used to a hotter cam and it’s fuss. This my first :)
  15. ALRIGHT! Whew what a crazy couple of weeks, sorry for the radio silence, but I was tending to it all . Aside from all the mishaps along the way, I crashed my motorcycle and broke my foot. But got her all put back together now. Thanks for the advice everyone, might need a little more. For the Cam I went with: COMP CAMS Xtreme energy with a 32-242-4 with a lift of .513/520 duration 218/224 @.05 Headed everyones advice and fought the urge to go much hotter. Also got: Matching lifters Comp cams 221 double roller timing set Comp Cams magnum pushrods 7502 Break in additive. I didn't get new springs because the rebuilt heads I bought definitely had some Comp Cam performance springs, retainers and keepers. Didn't realize I'd have to drop the oil pan in order to do the timing... that was a pleasant experience. Will say its definitely doable by disconnecting the engine mounts and jacking up the engine. ALSO went through the god forsaken Cam break-in tip of removing the inner spring in all my dual spring valve springs, broke in the cam, and then put them back in. Did a rough timing adjustment on the dizzy with a vacuum gauge. SO. She seems to running good, a lot more power, HOWEVER not idling too great and seems to be at a loss of power. When she's cold, the idle goes up and down (Surges?) between 1000 and 500 RPM making for a real uneven lopsided idle. After she warms up, this seems to go away or at least get a lot better and stay steady around 750 RPM. Also I'm only pulling about 15 pounds of manifold vacuum at idle. I've checked for vacuum leaks from the hoses and manifold, and non found. Going to look some more. I have new taylor plug wires, my spark plugs are in good shape. Adjusted my brand new quick fuel carb with a vacuum gauge (about 1.5 turns out on each screw) floats are about half way up the glass. Any suggestions of what else to check? Could an old coil cause this ? Maybe my new carb is faulty?
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