Welcome to CPGNation.com! Log in or Sign up to interact with the CPGNation community.

MALFUNCTIONING IAC???

Discussion in 'FAST Support Forum' started by 78 F150, Aug 9, 2018.

  1. 78 F150

    78 F150 Member

    Joined:
    Feb 6, 2013
    48-60 inches of rain?!?! Holy crap that's a ton of rain in such a short period of time. Heck, our annual rainfall where I live is only 19". I would living where you're at. I hate the rain.
    So when do you get the resonators installed?
     
  2. Fastmanefi

    Fastmanefi Well-Known Member

    Joined:
    Jun 4, 2011
    Location:
    Sonora, CA
    Not to be nasty, but why don't you guys communicate via private email. I think the forum is supposed to help users and your 33 pages of comments can't really do that. Please don't be offended. Just my opinion.
     
  3. 78 F150

    78 F150 Member

    Joined:
    Feb 6, 2013
    Fastmanefi--I understand what you're saying. However, if you've read through these pages you'd see that 99.9% of the conversation has been on topic about resolving specific issues. Right now I'm waiting on my heads to get back from the machine shop, which will be towards the end of January. In the mean time, we've made some personal, off topic comments these last few messages. But we'll get back on topic once my heads arrive and I get the engine back together. Then I'll need help tuning.
     
  4. fabr

    fabr Member

    Joined:
    Jan 23, 2017
  5. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    This thread belongs to the OP. He has the right to say what he wants here. He's not bothering anyone in his own thread. If others don't like his thread, they have every right to stay out of his thread.

    Oh, and posting my thread here in this manner and the "alternative" remark was very rude. That link and remark should be removed from your post here.
     
    Last edited: Jan 5, 2019
  6. fabr

    fabr Member

    Joined:
    Jan 23, 2017
    I guess you are right. I mean you have a 6 page thread with only 7 replies about your truck. It would appear you started it and as you say have the right to say whatever you want in it. Too bad there wasn't much interest in what you were saying though since this is a forum for FAST efi issues. But,you are right.
     
  7. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    So little interest there that the Sr. FAST software engineer liked my posts there.

    One of the things FAST wanted here was to insure no one was alienated. Try taking a look at how many reads popular threads have.

    I started that thread as a guide, and it continues to be a good one.

    While you're at it, you might take a look at my member status here as well.
     
    Last edited: Jan 4, 2019
  8. Fastmanefi

    Fastmanefi Well-Known Member

    Joined:
    Jun 4, 2011
    Location:
    Sonora, CA
    Cool. Have fun.. :^)
     
  9. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    Hey Richard, I know you meant no harm. I tend to go off topic at my age, and the posts I removed reflected something that just didn't have much to do with automotive enjoyment.;)
     
  10. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    I see fabr hasn't removed his snarky remarks. This is only one place of several on this site he has made such unwarranted obtuse comments to and concerning members. I'll just report the posts and refuse any further dialog with fabr. I've actually had him on my block list ever since he started this trolling behavior in the FAST forum. I suggest others do the same.
     
  11. fabr

    fabr Member

    Joined:
    Jan 23, 2017
    You are a bit off base there AA.
     
  12. 78 F150

    78 F150 Member

    Joined:
    Feb 6, 2013
    So my adjustable vacuum advance canister will be here tomorrow. Finally!! I've been waiting for it since October 2018!

    FABR--Thanks for providing the link to AA's thread on his truck. I read through all of it and it helped a lot. I took some notes also.

    AA--Excellent write-up on your truck. I listened to both videos of your new resonators and I can notice a big difference in noise level. I also noticed the drone sound once you hit 2250 rpm. I noticed in in both videos, even with the resonators. What is causing that drone sound? Is it the location of your mufflers? Would staggering them help eliminate that sound? Do you have a H or X pipe installed? Maybe that would help???

    Your truck sounds awesome! I can't wait to get my new exhaust installed. I did notice that your a/f ratio reading was very stable and only moved around a little bit and it moved pretty calculated and slowly, which is the total opposite of mine. I can see a big difference in your readings vs my readings. Your readings definitely verify I have a problem somewhere that I haven't found yet. Hopefully getting rid of the inserts and the new vacuum advance solve the issues. We'll see. Still waiting on the heads to get back. It'll probably be the end of January before they arrive. They're not done yet. I'll check with him next week to see where we're at and how much longer.
     
  13. fabr

    fabr Member

    Joined:
    Jan 23, 2017
    You are welcome. I posted it because it seemed more appropriate to discuss AA's mufflers there since he has already posted a lot of info in it about his exhaust. It wasn't meant to be "snarky".
     
  14. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    Lol, that canister would have shown improvement way back. At least you have it now. It and the head repair should make the difference.

    The GMC uses an X-pipe. The drone has never been very noticeable on the highway. I think I did once notice some droning running 75-80 mph, but that is probably gone now. 70-75 is all I mostly run on the interstate - and the truck is run under 50 most of the time. My truck was factory geared for highway running, and is easily capable of triple digit speeds - but I just don't drive that fast anymore. Even with the tall gearing, the truck still has more than enough torque off the line - I once pulled off a 350 big cam Cummings in a KW with it. Backed into the garage kind of amplifies the exhaust. I can even hear a difference between high and low humidity days in there. The new resonators are behind the mufflers. I have no idea what staggering them would accomplish. The drone sound is just exhaust pulse resonation.

    When you get your heads back, try using a Cometic gasket to get more accurate compression. Most replacement gaskets for Ford engines destroy compression ratios figured on paper, and give rise to detonation problems. Piston to deck height, gasket bore crevices, and quench height need to be correct.
     
    Last edited: Jan 11, 2019
  15. 78 F150

    78 F150 Member

    Joined:
    Feb 6, 2013
    So I'm considering just buying a new fuel tank instead of messing with my current fuel tank and trying to clean it out by using the fuel treatment. I can get a tank from RockAuto for $115. So I have a question....Do I need a tank with or without Evaporative Emission Control? I think I need the tank WITHOUT the EEC. I suppose I should just look at the type of tank I already have in my truck, but with this EFI I thought I might need a different tank now. I just wanted to verify.
     
    Last edited: Jan 13, 2019
  16. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    The only reason for an EFI tank would be to use an EFI in-tank pump system. I would use the tank that matches your current tank. If replacing the fuel pickup assembly - you could get one with the added fuel return line. But, since you have that all installed at the filler neck, it's not needed. I'm not sure, but EEC is usually provided by the type fuel pickup assembly used. You've also already got new caps. So, I would just stay with the tank that matches yours. They may be able to match one using your VIN.
     
  17. 78 F150

    78 F150 Member

    Joined:
    Feb 6, 2013
    AA--So I spoke with Henry at the machine shop last week and the heads finally made it to the welder (They've had my heads since 1/2/19. Not sure what is taking so long to get this job done). While talking to him he mentioned that the springs that came with heads do not have the same seat pressure. He also mentioned that it looks like some of the valves that had the weaker springs were bouncing off the seat (not sure how he can tell this just by looking at them). So he's going to shim the springs that need it so they all have the same spring pressure.

    So here's my question......would a valve bouncing off the seat cause an erratic & crazy a/f ratio such as I'm experiencing? Is it possible it's disguised as a vacuum leak and that's what's showing up on my handheld with the erratic a/f ratio?
     
  18. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    I've been wondering what happened with your project.

    It's not hard to spot weak valve spring to seat pressure by hand when disassembling a head. If the valves were bouncing, visual deformity will show up in the valve seat area - requiring a fresh valve job. While the valve seat job should be included with your head welding work, the shims and spring pocket machining may be an extra charge. He really should have urged you in this direction.

    Weak springs will cause erratic problems with vacuum - not to mention eventual reliability problems. If some of the valve springs are weak now, all will continue to weaken worse. Vacuum problems do affect A/F. I would recommend making sure the valve spring pockets are properly machined and shimmed for the correct spring height and seat pressure, and replacing the springs with a better quality set designed to match your camshaft. This will add greatly to the cam lobe life, valve seat and valve life. I have no idea what springs your heads came with, but they should have held up better if they were matched to the camshaft.
     
    Last edited: Feb 3, 2019
  19. 78 F150

    78 F150 Member

    Joined:
    Feb 6, 2013
    Yeah, I've just been playing the waiting game and haven't been on here much lately because of some people complaining about our "small talk" while I'm waiting for my heads to get back. In the mean time, I read both of your threads on your truck and the intake manifold. Learned a lot from your write-ups, but I'll need to reread them because my memory isn't that great.

    I really expected the heads to be back by now, but I realize I'm not the only customer they have. I'm trying to be patient but this is getting ridiculous.

    Yes, I'm going to have him do a valve job. I sent him my cam specs so I assume he knows what spring pressure I need. When he does the valve job, he's going to back cut the valves about 33* (like I originally had done) to increase the air flow. Doing the valve job was not included in the price of welding up the holes and retapping for new threads. I'll be talking to him a little more in depth about the valve springs/seat pressure matching the cam, especially if you think it can be causing my vacuum &/or air/fuel ratio problems.

    Here's the exact heads I have: https://www.summitracing.com/parts/fms-m-6049-scja The notes state: These heads are equipped with valve springs for flat tappet or hydraulic roller camshafts, seat pressure 130 lbs., open pressure 340 lbs. Here's the cam I have (It's a hydraulic roller): https://www.summitracing.com/parts/crn-359341 So can you tell me if these springs will work with my cam? How much spring seat pressure do I need with my cam?

    Here are the springs that are recommended for my cam. I'm not sure how much seat pressure these have compared to the springs I have on my heads: https://www.summitracing.com/parts/crn-96870-16/overview/ Should I go ahead and just buy these springs and be done with it? Or can the machine shop shim my springs enough to have the proper seat pressure and still not have issues with coil bind? Not sure which direction to go. Logic tells me to just buy the new springs. Your thoughts?

    I found this info on this website: http://www.crankshaftcoalition.com/wiki/images/1/11/Crane_pdf.pdf

    HYDRAULIC ROLLER CAMS require higher spring seat pressures to control the heavier roller tappets and the more aggressive opening and closing rates available to roller cam profiles. a. Small Block applications: 120-145# seat pressure b. Big Block applications: 130-165# seat pressure

    HYDRAULIC ROLLER CAMS use higher open pressures to control the high vertical opening inertia of the heavier roller followers. a. Small Block applications need at least 260# for general driving applications up to 4000 RPM. b. Moderate performance small block applications like 300-360# open. c. Serious small block applications can tolerate 400-425#* open pressures and still expect reasonable valve train life when top quality springs, pushrods, and lubricants are used. d. Big Block applications need at least 280# for general driving applications up to 4000 RPM. e. Moderate performance big block applications like 325-375# open pressure. f. Serious big block performance applications can tolerate 450#* open pressure and still expect reasonable valve train life when top quality springs, pushrods, and lubricants are used. *Note: Open pressures in excess of 360# require the use of roller tappet bodies made of billet steel. Crane hydraulic roller and solid roller tappets are made from heat treated steel billet to withstand the stresses of high-performance use. Most stock hydraulic roller tappet bodies are made of cast iron and cannot tolerate high spring loads.
     
    Last edited: Feb 3, 2019
  20. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    Don't worry about the talk. You need help, and talking is the only way to get it. I was expecting you to have those heads a week or so back - and was getting concerned something had happened to you. I would like to see you get the problems all resolved like others I've helped here.

    The springs that come on those heads should be compatible. But, here's what I would do. Since I've always had good luck with COMP dual springs, I would give them a call to see what they recommend. They may want to offer a "Beehive" single spring, but I would stick to the dual springs. Their recommendation may require a change to the spring pocket and retainer, but I would trust their springs to be of better quality. Whatever, I would replace those springs with springs that give the correct pressure on the seat at the recommended installed height. COMP may have a "race" style dual spring that will hold up more reliably. Your cam is large enough a race style spring may be preferable - even though this is only a street engine.

    Closed valve seat pressure is only part of the equation. It's important you have a specific open pressure and correct spring rate as well with your hydraulic roller. I didn't see anything concerning the lbs. per inch rate of your current spring at full valve lift. I have a feeling your current spring rate may be incorrect for your cam grind.

    The machine shop should have a good recommendation for a specific spring.
     

Share This Page