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Thread: FRPP 427W tuning problems

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    FRPP 427W tuning problems

    Ok not in a FFR but I know you guys have a few of em. Its installed in a 1964 Fairlane with a TCI AOD behind it. Everything is set according to the FRPP paperwork. It has a Victor Jr intake, MSD dizzy and 6AL box with MSD wires topped off with a Quick Fuel 750 DP with electric choke. Timing set at 16deg initial and 32 total around 4000rpms. Im on my 4th set of 3924 spark plugs in 3000mi. This thing is rich as hell and wont hardly run. Just been pushing through trying to get a tune on it through those miles. Carb is jetted per Fords manual on the engine, think its 80s and 86s. Ive even gone as far as putting my 600 Holley on it and it still doesnt run worth a flip. My stage 2 tuned Focus ST will beat it in a drag race. I cant figure it out. Any ideas??
    If in doubt......flat out-Colin McRae

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    Seasoned Citizen NAZ's Avatar
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    Of course I have no clue about your experience level so don't take offense but that's not really enough info to suggest what action to take. Rich at idle, cruise, WOT??? Do you have an AFR meter or are you deeming it rich because the plugs are sooty? Can you tell the difference between rich and oil fouled plugs? Do you see black smoke out the exhaust (rich) or blue smoke (oil)?

    If you're not experienced at tuning carbs I'd advise you to first sit down with a good book on tuning Holley carbs (your QFT is a Holley clone). A good book that's been around a long time is from HP Books titled Holley Carbs by Mike Ulrich & Bill Fisher. It's dated (then so is your carb) but will get you started in the right direction. My QFT has more than 50 adjustments which equates to hundreds of combinations you can tune to. Such simple technology but so many tuning adjustments beside main jets and turning those four idle mixture screws. I have a large assortment of main jets, emulsion jets, idle jets, air bleeders, squirters, accelerator pump cams, power valves, PVR jets, throttle plate control linkage, and decades of experience to support my tuning efforts. Carbs can be frustrating for the novice but everyone starts somewhere. And a good book is the best place to start if your experience is limited.

    Or if you need it now take it to a shop that deals with old school performance cars. Not sure any of the latest generation of auto techs have any experience with carbs. If they don't have gray hair they may have never worked on a crab.
    Dart Little M 406" SBC 800 HP N/A & 1,100 HP on nitrous, 2-spd Powerglide with trans brake, 6,000 RPM stall converter, narrowed Moser 88 3.90:1 spool with 35-spline gun-drilled axles & Torino bearings, custom parallel four-link, custom tube chassis & roll cage NHRA certified for 8.5-sec (only two FFR Hot Rods have this cert).

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    Rich at idle and cruise but give it the beans from a roll and it comes alive. I do not have a wideband O2 on it but the plugs are usually fuel soaked and sooty. Ive tuned multiple carbs from Holley 600s to 48 IDF Webers and 2 stroke RC engines and have never had a problem like this. Ive also sprayed carb cleaner around all mating surfaces to see if it was a vacuum leak and no luck.
    If in doubt......flat out-Colin McRae

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    Is the carb new? One of the many possibilities is you have a leaking power valve. Have you adjusted the idle mixture screws? Do you know what vacuum the motor pulls at idle? You have to have the correct powervalve in it.

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    Carb was new when installed. Tuned 4 corner idle circuits and achieved right at 8" vacuum at idle so I installed a 3.5 power valve. Also went up to 76 idle air bleeds too with no change in idle quality.
    If in doubt......flat out-Colin McRae

    Coupe #485

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    Location "the hills of TN"?

    I built mine with the backup carb plan of "I know people with similar carbs / engines that work right - if I can't get mine right by myself - I know people whose carbs I can swap in / out / here / there / whatever / get it figured out".


    PM me.
    Last edited by mike223; 12-08-2018 at 03:51 PM.

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    Seasoned Citizen NAZ's Avatar
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    OK good, you’ve got some experience so this won’t be completely new. There are a few things you’ll need: an understanding of the your particular carb and how all the circuits work and logical & systematic approach to troubleshooting – that’s where a book on your carb comes in. For advanced tuning you might also want to pick up a copy of David Vizard’s Super Tune and Modify Holley Carbs. And the most import ground rule – only make one change at a time and evaluate it before going on.

    So how will you determine if you have the AFR correct? Reading plugs is much more difficult than most folks realize and you will go through a lot of plugs as adding layer upon layer of color on a used plug leads you to incorrect conclusions. I run leaded race fuel in my racecar and that is so much easier than reading unleaded plugs. There is way more to it than can be covered here. Of course a portable wide band AFR meter makes tuning quick and easy so if you plan to work with carbs consider buying one if you can’t rent one. You will also need a vacuum gauge and a tach.

    The first thing to do is the initial set-up which will include at minimum ensuring the transfer slots are not uncover too much (I like to start with ~.020” to no more than ~.050”), the electric choke is adjusted properly (the high-speed idle will be set later), the accelerator pump linkage is adjusted properly (.015” short of full stroke at WOT), the idle mixture screws are backed out 1.5-turns, the fuel pressure is between 5 & 7 PSI, and the fuel level in the bowls is correct when idling.

    The first circuits you will adjust are the idle then the accelerator pumps before you even consider adjusting the high-speed circuits. Remember, the idle circuit is active at a much higher speed than most realize so if you are rich at idle and cruise and you have screw-in bleeders you may want to start with the idle air bleeds -- they are the larger of the eight and the ones on the outboard. They are not nearly as effective as the smaller high-speed bleeds so change in steps of three size increments and evaluate. Increasing their size leans the idle circuit. There are also idle feed restrictors and on some carbs, emulsion jets to trim the idle and cruise mixtures.
    Dart Little M 406" SBC 800 HP N/A & 1,100 HP on nitrous, 2-spd Powerglide with trans brake, 6,000 RPM stall converter, narrowed Moser 88 3.90:1 spool with 35-spline gun-drilled axles & Torino bearings, custom parallel four-link, custom tube chassis & roll cage NHRA certified for 8.5-sec (only two FFR Hot Rods have this cert).

    33 Hot Rod Super Pro Drag Racer Build: 33 HR NHRA Cert Roll Cage Build

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    Ive done that exact procedure about 10 times per Quick Fuels setup videos on you tube. Anybody ever just get a bad out of the box carb??? Thats why Im lost. Ive also tried out two different MSD boxes with no change.
    If in doubt......flat out-Colin McRae

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    Seasoned Citizen NAZ's Avatar
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    Never had a Holley out of the box that was perfect and never had one out of the box I couldn't tune. And I think you eliminated the 750 when you installed the 600 and it was still rich. But one thing that I find troubling is you stated that you set the idle and best idle showed 8" of vacuum. I live at 7000' ASL and summertime density altitude is usually around 9000' or even 10000'. At 9000' DA my race set-up pulls 11.5". This is a 385 CI with a healthy cam that lopes under 1500 RPM, a high rise with a huge open plenum, and a 1050 CFM 4150 QFT. I wouldn't expect your DA to be anywhere close to mine even if you live in the Smokies and unless you have a ton of overlap on your cam I'm at a loss to explain that relatively low vacuum. You should see ~1" less vacuum per 1000' of increased elevation. The low vacuum itself may not be a contributing factor but; is what's causing the low vacuum a contributor?

    Don't give up, keep troubleshooting your way out of the problem. One logical step at a time. That car is not smarter than you.
    Last edited by NAZ; 12-08-2018 at 05:31 PM.
    Dart Little M 406" SBC 800 HP N/A & 1,100 HP on nitrous, 2-spd Powerglide with trans brake, 6,000 RPM stall converter, narrowed Moser 88 3.90:1 spool with 35-spline gun-drilled axles & Torino bearings, custom parallel four-link, custom tube chassis & roll cage NHRA certified for 8.5-sec (only two FFR Hot Rods have this cert).

    33 Hot Rod Super Pro Drag Racer Build: 33 HR NHRA Cert Roll Cage Build

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    You said you also tried a different carb with same results. So That to me would rule out a carb problem.I have had bad luck with many 6AL boxes . will your dist allow you to run without the box? Maybe somebody has a known good box. Just because a part is new doesn't mean its good.

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    Quote Originally Posted by first time builder View Post
    You said you also tried a different carb with same results. So That to me would rule out a carb problem.I have had bad luck with many 6AL boxes . will your dist allow you to run without the box? Maybe somebody has a known good box. Just because a part is new doesn't mean its good.
    I have 2 6AL boxes. Both have same results. Im leaning toward pulling dizzy and checking gear and possibly replacing coil. Gonna check the dizzy gear to see if its worn to make the timing wander around.
    Last edited by TNcoupe; 12-08-2018 at 07:38 PM.
    If in doubt......flat out-Colin McRae

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    Seasoned Citizen NAZ's Avatar
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    What ignition system fault symptoms are you experiencing? When you say it's rich and won't hardly run is it missing? And has it ran like this all along? It just doesn't make sense that when you "give it the beans it comes alive" as an ignition issue will usually be problematic continuously or if only during one stage of running it would be more likely to be at WOT under load when cylinder pressures are higher and making a spark is more difficult.

    But timing could (not really an ignition fault) cause a miss fire at slow speed if it doesn't have enough lead. You would also see elevated exhaust temps with the timing retarded.

    You say you've got the base timing set at 16-deg but have you confirmed that your pointer is zero at TDC? If the pointer is not zeroed at TDC your actual timing could be significantly different than what you think. It's a condition I've seen before. The only way to be sure is to actually find true TDC and verify your timing pointer is at zero. The easiest way to do this on an assembled engine is with a TDC finder. You can buy them but I usually make mine out of old spark plugs. It's essentially a piston stop that threads into the #1 spark plug hole. You bring the piston up on the compression stroke and insert the stop. Rotate the crank until it stops (piston contacts the stop) and accurately mark the damper corresponding to the pointer. Rotate it the opposite direction again until it stops and mark the damper again. TDC is exactly between these two marks and that's where your pointer should be zeroed.
    Dart Little M 406" SBC 800 HP N/A & 1,100 HP on nitrous, 2-spd Powerglide with trans brake, 6,000 RPM stall converter, narrowed Moser 88 3.90:1 spool with 35-spline gun-drilled axles & Torino bearings, custom parallel four-link, custom tube chassis & roll cage NHRA certified for 8.5-sec (only two FFR Hot Rods have this cert).

    33 Hot Rod Super Pro Drag Racer Build: 33 HR NHRA Cert Roll Cage Build

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    NAZ, I havent used a piston stop but I have dropped a screwdriver in the spark plug hole and rotated the engine around on compression stroke and when the piston topped out the timing mark was right at 0 on the damper. As soon as this stupid rain quits Im gonna get out and mess with it some more.
    If in doubt......flat out-Colin McRae

    Coupe #485

  14. #14

    Steve >> aka: GoDadGo
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    TN,

    Do you have any pals that are running an Edelbrock AVS or Performer series carb that you could try?

    I'm running an open plenum intake (Team-G) but a smaller engine (383) and am having good luck with an AVS-800.
    For the record, I can't tune a Holley, or Holley Clone to save my life so I stuck an Edelbrock on mine and it runs well with only very minor adjustments having been made.
    It can't hurt if you have access to a short-term loaner carb and a little time.
    If it burps or pops there is no power valve to blow out.

    Good Luck From The Dell, Slidell Louisiana That Is!

    Steve
    Last edited by GoDadGo; 12-08-2018 at 09:32 PM.

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    Quote Originally Posted by TNcoupe View Post

    and 32 total around 4000rpms
    Ok, so you haven't said if you're running vacuum advance or not - doesn't matter.

    If you do have vacuum advance - plug it off for now.

    Assuming your timing marks are right (screwdriver at tdc you mentioned sounds good) - you probably actually need 36 -38 degrees "total" mechanical advance in (wot / full load) no later than ~2800 rpms.

    If you're trying to run vacuum advance on top of that - good luck - many variables.

    Screw it up a little = burned piston(s) / blown engine.


    But 32 degrees at 4000 isn't going to get it done.

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    Senior Member Avalanche325's Avatar
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    Two carbs, same symptoms. What is your fuel pressure set to?
    Did you set your transition slots before you put the carb on?

    The very first thing is to get the timing right.
    Then get it to idle correctly. Everything else adds on top of that. Don't play with anything else until that is done.

    You really really really need an O2 to set up a carb. Or 20 years experience.

    Wayne Presley's Carb tuning 101.
    https://www.ffcars.com/forums/17-fac...ing-101-a.html

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    Think I figured it out today. Buddy let me borrow his boroscope. Every intake runner is oil soaked just past the intake gaskets. Looks like its sucking oil in past the gaskets from the lifter valley. I would assume this would make it hard to tune due to trying to burn oil and I guess losing vacuum that way. Last time I changed the oil it did smell a little like fuel, I assumed it was cause of a super rich condition and blowby. Hoping this is the real problem.
    If in doubt......flat out-Colin McRae

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    Seasoned Citizen NAZ's Avatar
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    Post #12 above (sorry, #9): The low vacuum itself may not be a contributing factor but; is what's causing the low vacuum a contributor?

    Looks to me like you found the source of your low vacuum and that may also be your prime suspect for running poorly.

    It would take a lot of oil to affect AFR enough that the engine would run poorly and you would see lots of blue smoke out the exhaust before that happened. But sucking oil through an intake gasket may also introduce an air leak affecting the AFR. You first said it's rich at idle and midrange and that is just the opposite condition you'd see from an intake manifold air leak. But this could be the reason your idle vacuum is so low -- 8" at best idle is very low unless you have a very lopy cam with lots of overlap. And if you're not real familiar with reading plugs you may have mistaken oil fouling for a rich mixture on the plugs. They are both black but one is typically shinny and the other dull.

    Regardless, an oil leak into the intake is a problem that needs to be resolved before going further.

    But once that's done, I suggest you get a Wideband O2 meter to tune your engine. I don't think you should rely on reading plugs. I've been studying plugs for half-century and can tell if the timing is right by the ground strap, the heat range is correct, if there is evidence of detonation, oil fouling, and gross rich or lean -- but AFR from color especially with unleaded fuels is still not as simple as reading it off an AFR gauge. I use a Wideband sensor when I tune a carb. And reading plugs requires reading new plugs if you want to get it right. If I want to infer from a plug what the AFR is at WOT I have to make a pass and shut the engine off in neutral, coast off the track and get a tow back to the trailer. Even idling in the staging lanes will color a plug and make it difficult to read what's happening at WOT. It's just not that simple as folks make it out to be.
    Last edited by NAZ; 12-20-2018 at 08:04 AM.
    Dart Little M 406" SBC 800 HP N/A & 1,100 HP on nitrous, 2-spd Powerglide with trans brake, 6,000 RPM stall converter, narrowed Moser 88 3.90:1 spool with 35-spline gun-drilled axles & Torino bearings, custom parallel four-link, custom tube chassis & roll cage NHRA certified for 8.5-sec (only two FFR Hot Rods have this cert).

    33 Hot Rod Super Pro Drag Racer Build: 33 HR NHRA Cert Roll Cage Build

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    Now the question is do I change it to a dual plane intake while I have this thing off changing the gaskets. Its 99.9% street driven and has the Super Victor 351 intake on it now.
    If in doubt......flat out-Colin McRae

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    Seasoned Citizen NAZ's Avatar
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    Look at several dyno tests of single vs dual plane and I think you will answer your own question. A Super Vic single plane is a great high-speed manifold and makes a lot of upper range HP. But not most folks' first choice for a street car. I believe you would be much happier with most any dual plane over the single plane you have if this is a street cruiser. And I bet you could sell that high performance manifold and recoup some of the cost of the new manifold. Drag racers love these manifolds.
    Dart Little M 406" SBC 800 HP N/A & 1,100 HP on nitrous, 2-spd Powerglide with trans brake, 6,000 RPM stall converter, narrowed Moser 88 3.90:1 spool with 35-spline gun-drilled axles & Torino bearings, custom parallel four-link, custom tube chassis & roll cage NHRA certified for 8.5-sec (only two FFR Hot Rods have this cert).

    33 Hot Rod Super Pro Drag Racer Build: 33 HR NHRA Cert Roll Cage Build

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    Yeah I ordered everything based off Fords recommendations. Every engine I have built I made the combo myself and just went off Ford paperwork for this one. After a little research I found the Super Vic makes power above 4500rpms...bit much for the street.
    If in doubt......flat out-Colin McRae

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    Quote Originally Posted by TNcoupe View Post
    Yeah I ordered everything based off Fords recommendations. Every engine I have built I made the combo myself and just went off Ford paperwork for this one. After a little research I found the Super Vic makes power above 4500rpms...bit much for the street.



    Ok, first question is who gave you the idea that ~32 degrees @ ~4000 was going to work on this engine?


    Second statement: SBF print-o-seal intake gasket problems are well documented on google - you need the *S3* (or other steel laminate) gaskets if you don't want to take a chance on them collapsing or failing on you in three years or less (I hear they were originally intended for race engines that are coming back apart in less than three years).

    If you ran print-o-seal gaskets that only failed + drew oil in from the galley, then you got lucky - because they occasionally dump (full load) coolant into the intake runners (at the worst possible moments).

    It's all pretty well documented on google.


    Good luck.

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    Quote Originally Posted by mike223 View Post
    Ok, first question is who gave you the idea that ~32 degrees @ ~4000 was going to work on this engine?


    Second statement: SBF print-o-seal intake gasket problems are well documented on google - you need the *S3* (or other steel laminate) gaskets if you don't want to take a chance on them collapsing or failing on you in three years or less (I hear they were originally intended for race engines that are coming back apart in less than three years).

    If you ran print-o-seal gaskets that only failed + drew oil in from the galley, then you got lucky - because they occasionally dump (full load) coolant into the intake runners (at the worst possible moments).

    It's all pretty well documented on google.


    Good luck.
    Page 12 of the FRPP 427W instruction manual. You know Ford right? The people that have been building engines and cars since 1903. Figure they have a little more experience with big inch Windsor strokers than I do so I decided to follow their instructions as to possibly not void the engine warranty thats why I also used the intake gaskets that were supplied with the engine.


    Capture.PNG
    If in doubt......flat out-Colin McRae

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    Quote Originally Posted by TNcoupe View Post
    Page 12 of the FRPP 427W instruction manual. You know Ford right? The people that have been building engines and cars since 1903. Figure they have a little more experience with big inch Windsor strokers than I do so I decided to follow their instructions as to possibly not void the engine warranty thats why I also used the intake gaskets that were supplied with the engine.


    Capture.PNG

    Excellent reference.

    I don't think you'll ever get it to run right timed like that.

    But as the manual says - there are many variables.



    Good Luck.
    Last edited by mike223; 12-20-2018 at 08:48 AM.

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    Well I think I finally got the issues sorted. Changed intake gaskets to 1262Rs and got the vacuum up to 14". Quick Fuel 750 still wasn't running right after all my tuning adjustments. Dropped at Holley Sniper EFI on it and got it dialed in now. Sits and idles at 950 rpms with an AFR around 13:1 at idle and runs like a champ all the way up to redline. After wiring this Sniper up and running the fuel lines I doubt I will ever do a carb again.
    If in doubt......flat out-Colin McRae

    Coupe #485

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    Senior Member Avalanche325's Avatar
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    I'm glad you got it running and are happy.

    My thoughts on single vs dual plane intakes, since that came up. Yes, the old school rule is single for the track and dual for the street. However, one size fits all rules are really one size fits most. Cobras are outside of the "most" category. Lightweight and a high power to weight ratio makes a single plane intake a good choice for these cars, if you have a decent amount of power. There is another most. It is a good thing to move the power up the RPM range a little, since you can't use much of the throttle off the line.

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    Quote Originally Posted by TNcoupe View Post
    Well I think I finally got the issues sorted. Changed intake gaskets to 1262Rs and got the vacuum up to 14". Quick Fuel 750 still wasn't running right after all my tuning adjustments. Dropped at Holley Sniper EFI on it and got it dialed in now. Sits and idles at 950 rpms with an AFR around 13:1 at idle and runs like a champ all the way up to redline. After wiring this Sniper up and running the fuel lines I doubt I will ever do a carb again.
    Glad you finally found a solution to your tuning issues. I tip my hat to you for trying to make the Quick Fuel 750 work. It sounds like we have a similar engine/carb set up and, I like you, will try a lot before giving up on the carb. But I'm getting real close to it.

    I am entering what I will call "tuning season" as my Quickfuel hotrod 780 still doesn't run the way it should and never has. I will be the first to admit I am not a tuner and based on others comments about all the variables, tuning is way above my pay grade. Last fall I spent 2 1/2 days at a local speed shop with no success $$$ and came away with a new distributor $$$. If I choose to switch to EFI, will my mechanical fuel pump be sufficient or will I need to add an electric fuel pump .

    Thanks
    Mk4 Roadster 20th Anniversary #8658. 04 of 20. 3.31 IRS.
    Forte 427 Dart, TKO 600, Quick Fuel 780 carb. Delivered 9/2/2015, First start/Go Cart 2/18/2017.
    Road Legal August 31, 2017

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    Quote Originally Posted by ThickCobra View Post

    If I choose to switch to EFI, will my mechanical fuel pump be sufficient or will I need to add an electric fuel pump .
    Switching to EFI will require a electric fuel pump.

    Your mechanical pump runs 5 to 8 psi - EFI requires 40 to 60 psi depending on the flavor.


    P.S.

    Reviewed this thread and something jarred my memory - I got my Holley 750 mechanical secondary running perfectly in the first place (with very little trouble or heartache) and then tried to implement PCV - I never did find one that I could run with, they were all too big a vacuum leak (started with PCV valve for 1967 427 Corvette, tried several 1960s SBC PCV valves after that, never found one that worked right). All this on 393W / 10.5:1 / .600 lift solid roller cam.

    Ended up venting the valve covers to the air filter / breather through a marine type flame arrestor - still works great.

    Anyone who's having these sorts of problems might want to try blocking the PCV off and see if it acts better.


    From there you could probably go this route: https://www.hotrod.com/articles/tuna...-engine-leaks/
    Last edited by mike223; 03-20-2019 at 08:39 AM. Reason: P.S.

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    Quote Originally Posted by mike223 View Post
    Switching to EFI will require a electric fuel pump.

    Your mechanical pump runs 5 to 8 psi - EFI requires 40 to 60 psi depending on the flavor.


    P.S.

    Reviewed this thread and something jarred my memory - I got my Holley 750 mechanical secondary running perfectly in the first place (with very little trouble or heartache) and then tried to implement PCV - I never did find one that I could run with, they were all too big a vacuum leak (started with PCV valve for 1967 427 Corvette, tried several 1960s SBC PCV valves after that, never found one that worked right). All this on 393W / 10.5:1 / .600 lift solid roller cam.

    Ended up venting the valve covers to the air filter / breather through a marine type flame arrestor - still works great.

    Anyone who's having these sorts of problems might want to try blocking the PCV off and see if it acts better.


    From there you could probably go this route: https://www.hotrod.com/articles/tuna...-engine-leaks/
    More to consider. Thanks.
    Mk4 Roadster 20th Anniversary #8658. 04 of 20. 3.31 IRS.
    Forte 427 Dart, TKO 600, Quick Fuel 780 carb. Delivered 9/2/2015, First start/Go Cart 2/18/2017.
    Road Legal August 31, 2017

  33. #30
    Member
    Join Date
    Feb 2011
    Location
    The hills of TN
    Posts
    81
    Post Thanks / Like
    The Holley Sniper kit if you buy the complete kit comes with an electric fuel pump that must be mounted at the tank and below it to make sure it maintains positive suction.
    If in doubt......flat out-Colin McRae

    Coupe #485

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