Fox Need Help With Stock 351w For 89 5.0

Discussion in '1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-' started by Justin R, Nov 12, 2013.

  1. I have a stock 351w out of a 91 f150. The engine is in excellent running condition. I really hate to go into it and start with oversizing right away. I also wanted to get away from efi. Can I use the stock engine add a good cam, aluminum heads, Intake, holley carb? Or is it just a waste?? All opinions appreciated.
  2. Yep, you can definitely do all that. One concern might be that the engine will use a flat tappet cam- which kind of sucks. Sticking with the flat tappet means you'll have to follow a proper break-in procedure, and you'll be limited to what kind of lobe profile you can run compared to a roller. Alternatively you can spend an extra $3-400 on retrofit link bar roller lifters and run a roller cam, which would be more ideal.

    There also seems to be some concern in 351s with the durability of the stock rod bolts at high RPM. I can't speak to that personally, but most guys recommend upgrading bolts or running aftermarket rods if you plan to spin up the engine. You'll have to do some googling on that and kind of decide how you want to go in that regard.

    Finally, keep in mind that you can pretty much run a stock Mustang EFI setup (with larger injectors and fuel pump) on a 351. It's not too much hassle to stay EFI- it's actually probably less hassle than converting to carb is.
    A5literMan likes this.
  3. Ok great info. What kind of Hp should I expect if I were to go with like an afr heads, comp roller cam, efi. ?
  4. The sky is the limit here and your wallet will be the ultimate determining factor of the hp. What type of expectations do you currently have, hp goals or et goals if you are racing? I second the notion of converting to a hydraulic roller with the retrofit lifters!
  5. Is it possible to achieve 400-450hp
    Just by changing heads and cam to Hyd roller?
  6. Don't know if you also know that you have to change the oil pan,motor mounts,etc to get it to fit. If you are going to buy aftermarket h/c/i I'd def go with a roller cam and try to stay EFI. For heads stay above the 170cc (185-205) size heads.
  7. A properly spec'd topend is def capable of 400+ hp
  8. There is a guy on here with a stock bottom 351 (Venom351). He has a very large set of heads and a cam from FTI. The problem he ran into is that the stock pistons in the 351 required a little bit of a unique setup with the cam and heads to clear the valves. I think he will still be around 450hp though.

  9. You don't really have to change mounts unless you want to run drop mounts... But yea, there are a lot of things to consider when doing a W swap.

    I can't remember- is he running stock rods/bolts? @Venom351R

    Something to keep in mind is the possibility of notching pistons while still in the block.
  10. Agreed. But it's pretty difficult to fit an EFI 351 under a stock hood without them.
  11. Stay tuned to my build thread of my 84 ttop car. Stock steel hood going back on after the accident. I want a 7 second pass with a steel hood, new personal goal :)

    And before you ask, there will not be any cutting holes in that sucker to make it fit!
    A5literMan and 85rkyboby like this.
  12. Yeah it's a stock bottom end of some sort. Some sort of Cobra R engine. I remember pictures of the short block, and they were definitely stock looking pistons. Notching pistons in the block isn't that popular anymore, but it's doable.

  13. Thanks for all the help. I can't really make up my mind I feel like I need to just start from scratch and build up it's just going to take more $$..
  14. If you stick to a budget and be reasonable with your parts, it's not too bad.

  15. It's really not much more than a 302 build. It is more expensive don't take me wrong but like revhead said stick to a budget and do some research. There are a few extra nickel and dime pieces that add up.
  16. If you already have a complete engine though, most of those pieces aren't too bad. You're going to need an oil pan, distributor, stuff like that.

    #16 revhead347, Nov 12, 2013
    Last edited: Nov 12, 2013
  17. Yes its the stock rods and I have ARP Studs not bolts. The heads are 234cc Custom CNC Ported High ports. The Dyno day was canclled this summer and I never got a chance to go back again with other stuff that was going on. I did trap 110MPH on a few runs and the tune was worked on more since then. Hopeufully will have solid numbers next spring. The Heads were also from FTI and yes the Pistons are stock. Pics/101_0382_zpsd8050224.mp4.html

    #17 Venom351R, Nov 24, 2013
    Last edited: Nov 24, 2013
  18. 110 to the 1/8th or 1/4?
  19. Quartet
    In the quarter
  20. No offense, something is not adding up here. 351, custom cam, 234cc cnc ported high ports and only 110 mph in the quarter? What kind of power do you expect this combo makes? What were you ets? regardless of 60' times mph tells all when it comes to hp and you seem to be way under what I would expect that combo to make. What kind of cam specs?