tommyg Posted March 30, 2021 Share Posted March 30, 2021 Hi All, New here, but I've been searching around for a little while to find some info on the subject: Truck: 1986 F-250 4x4. 300 Six Engine, 1bbl carb. It currently has the stock setup that's kind of in rough shape, it runs but not well. Definitely needs the carb rebuilt or replace, and there's a ton of smog and vacuum line stuff missing. I was hoping to find someone that has done a similar job on this specific setup. I'm looking at getting this kit from Jegs: https://www.jegs.com/i/Offenhauser/750/6019-DPK/10002/-1 But before I drop the cash, I want to make sure I'm on the right track. I want to eliminate what I can from the smog/vacuum setup if possible since most of it is rotted or missing completely. The EGR tube from the header is badly rotted also, so I'd rather eliminate what I don't need in that regard. My main questions are: 1) Is this carb intake setup the right choice (it says 2WD models only on the Jegs site, but plenty of reviews have said that it fits fine on the 4x4 as well) 2) What can I eliminate from the vacuum system and what do I need to keep? (obviously the brake booster, but not sure after that) If there IS another post about this that I missed I apologize, I couldn't find one. I've been cruising over on Ford Truck Enthusiasts too and haven't found what I'm looking for. Thanks in advance. -Tom Link to comment Share on other sites More sharing options...
Gary Lewis Posted March 30, 2021 Share Posted March 30, 2021 Tom - Welcome! Glad you joined. You probably haven't seen the email I sent you asking you to go to the New Users Start Here folder, read the guidelines, and then start a new thread/topic to introduce yourself. But the main issue is to give you a chance to read the guidelines as we hold everyone to them. Where's home? I ask because we have a map (Bullnose Forum/Member's Map in the menu) and we'd be happy to add you if we had a city/state or a zip. On what you need in the way of vacuum systems, if you are eliminating the feedback system, meaning replacing the carb and removing all emissions systems, take a look at the page here: Documentation/Under Hood/Vacuum Systems. And if you are doing all that you'll not only need to replace the carb but also the distributor. That's because you should have a EEC-III system with a TFI ignition system on the side of the distributor, and if so it is controlled by the computer. And when you neuter the emissions systems the computer gets its knickers in a twist and locks ignition timing to whatever you have dialed in as initial timing. No advance means poor performance and economy. Also, without EGR you should change the timing curve in the distributor, so you should look for a pre-EGR distributor. Perhaps someone has a suggestion on that. Link to comment Share on other sites More sharing options...
myrl883 Posted March 30, 2021 Share Posted March 30, 2021 Tom - Welcome! Glad you joined. You probably haven't seen the email I sent you asking you to go to the New Users Start Here folder, read the guidelines, and then start a new thread/topic to introduce yourself. But the main issue is to give you a chance to read the guidelines as we hold everyone to them. Where's home? I ask because we have a map (Bullnose Forum/Member's Map in the menu) and we'd be happy to add you if we had a city/state or a zip. On what you need in the way of vacuum systems, if you are eliminating the feedback system, meaning replacing the carb and removing all emissions systems, take a look at the page here: Documentation/Under Hood/Vacuum Systems. And if you are doing all that you'll not only need to replace the carb but also the distributor. That's because you should have a EEC-III system with a TFI ignition system on the side of the distributor, and if so it is controlled by the computer. And when you neuter the emissions systems the computer gets its knickers in a twist and locks ignition timing to whatever you have dialed in as initial timing. No advance means poor performance and economy. Also, without EGR you should change the timing curve in the distributor, so you should look for a pre-EGR distributor. Perhaps someone has a suggestion on that. I'm gonna get hell for this, but a 302 is a perfect fix for a 300... Link to comment Share on other sites More sharing options...
Rembrant Posted March 30, 2021 Share Posted March 30, 2021 I'm gonna get hell for this, but a 302 is a perfect fix for a 300... LOL, it's funny for a couple reasons, but one is that I've been reading people complain for years that the 302 was a terrible truck engine haha. I have a mild fascination with the 300 six, but I too have been thinking about swapping it out for a 302...lol. Link to comment Share on other sites More sharing options...
Rembrant Posted March 30, 2021 Share Posted March 30, 2021 2) What can I eliminate from the vacuum system and what do I need to keep? (obviously the brake booster, but not sure after that) I know you're looking for a different carb and intake, but to answer your vacuum question, I just purchased a cheap YF on Amazon ($69?) and I currently have ONLY the brake booster connected to vacuum. The only other thing I will be connecting is the distributor advance. (I also have my 302 set up this way...brake booster and distributor advance are the only two things I have connected)....well, I guess you can add PCV on both engines. Edit: Just realized after I posted the video that I didn't even have the booster connected in that one lol, but I did connect it shortly afterwards. Link to comment Share on other sites More sharing options...
1986F150Six Posted March 30, 2021 Share Posted March 30, 2021 2) What can I eliminate from the vacuum system and what do I need to keep? (obviously the brake booster, but not sure after that) I know you're looking for a different carb and intake, but to answer your vacuum question, I just purchased a cheap YF on Amazon ($69?) and I currently have ONLY the brake booster connected to vacuum. The only other thing I will be connecting is the distributor advance. (I also have my 302 set up this way...brake booster and distributor advance are the only two things I have connected)....well, I guess you can add PCV on both engines. Edit: Just realized after I posted the video that I didn't even have the booster connected in that one lol, but I did connect it shortly afterwards. Welcome to the forum, Tommy! That kit is a lot of $$$! The 4.9L/300 engine is a work horse, not a quarter horse... there are those who [me, for one!] love its unassuming work ethic. It does what it does without complaining, as long as you don't mind a leisurely pace. By the way, just for trivia sake, the 4.9L/300 engine was offered by Ford in trucks only and up to the intermediate duty range [F600]. That is because of its low RPM torque delivery. On the other hand, the 5.0/302 has more horsepower and get up and go at higher RPMs, but was not offered in anything larger than a F250. If emission testing is not an issue, I recommend you replace the carburetor with a pre-emission Carter YF and replace the distributor with a recurved Duraspark. Use Motorcraft sparkplugs specified for FI engines [1987-1996]. What you will end up with is a reliable engine with good efficiency. The EGR tube, which you mentioned, can be removed and the threaded hole in the EGR spacer plugged with a 3/4" piping plug. EGR by itself, is a good thing, but if not functioning can be worked around. In the previous paragraph, it was mentioned that a recurved distributor will be needed... that is because without a functioning EGR system, the ignition timing will be too far advanced under cruise conditions and pinging likely will occur. Good luck with your project! Link to comment Share on other sites More sharing options...
Sac79 Posted March 30, 2021 Share Posted March 30, 2021 A guy asks specific questions about a fancy kit for his 6 and everyone responds with 'swap in a V8'... I'm disgusted! Or keep it stock... David. Each to his own. If you're sold on the headers, check out the kit from Clifford Performance, https://cliffordperformance.net/store/ols/products/68-ford-240300-combination , same price and I've heard they have excellent customer service. Also, the intake manifold is already plumbed for heat. The reason the kits are recommended for 2WD only is clearance issues with the headers. (carb and intake is not an issue) I have seen many examples in 4WDs though. You might just have to grind a little on the frame. I decided against going that route mostly to save money. Supposedly the EFI manifolds will get you close to the header performance. Can't say if that's true, but it's good enough for me. As Gary mentioned, biggest additional issue is going to be the distributor. You probably want to budget for a DSII swap or change to a HEI distributor(like I did). That would leave you with vacuum for the brakes as you mentioned, PCV and distributor. I kept my stock intake, so I also have vacuum for the snorkel. Of course the smog stuff will depend on your local/state requirements. Link to comment Share on other sites More sharing options...
myrl883 Posted March 30, 2021 Share Posted March 30, 2021 I'm gonna get hell for this, but a 302 is a perfect fix for a 300... LOL, it's funny for a couple reasons, but one is that I've been reading people complain for years that the 302 was a terrible truck engine haha. I have a mild fascination with the 300 six, but I too have been thinking about swapping it out for a 302...lol. You get alot more power for alot less cash! And they run smoother, too. 300 is a solid workhorse, but I'm just not a 6 cylinder fan. Link to comment Share on other sites More sharing options...
FuzzFace2 Posted March 30, 2021 Share Posted March 30, 2021 You get alot more power for alot less cash! And they run smoother, too. 300 is a solid workhorse, but I'm just not a 6 cylinder fan. On the vacuum what Cory posted is right but if you have AC, Cory is north of the border and AC is not really needed, you will need to hook that up to manifold supply. If I was you before dropping 2K try this. You will need a dist. even with the kit you posted or the Clifford kit. Either the factory DSII dist., box on the fender, wiring, and coil. OR Do the HEI dist. as it has everything built in and just drop it in. So with the dist. taken care of spend the $70 on the YF carb, remove the emission junk (EGR pipe & plug) air pump, vacuum lines other than posted above. See how it runs and if you don't like it keep the dist. and sell the carb / manifolds and buy the kit you listed. My 300 is using a DSII factory dist. and factory YF carb and intake manifold but ..... I am using EFI exh. manifolds. I just bought the cheap carb to replace mine as I was having issues but over the weekend I took my carb apart, cleaned it good again and checked & adjusted and it is working great again. Vacuum lines: Power brakes, carb to dist. advance, HVAC (I have AC), PCV, and vapor canisters under battery (I for got this above). No air pump, no EGR hooked up as it is plugged off but in place as a spacer. I like my 300 and its low RPM power. I also built it to pull my open deck car trailer if need be. Now if I can get a little more MPG out of it, mid 14's now, I would be a lot happier! Dave ---- try this link https://www.ford-trucks.com/forums/forum52/ Link to comment Share on other sites More sharing options...
tommyg Posted March 31, 2021 Author Share Posted March 31, 2021 Thanks Gary, new member requirement has been rectified. Obviously I got excited and just started spilling my guts out as soon as I joined. Forgive me. Link to comment Share on other sites More sharing options...
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