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8BA doesnt have power Hey guys. just starting to get my 47 pickup on the road with the newly rebuilt 8BA. It has the ford 94 carb rebuilt, edelbrock elect fuel pump, stock dizzy w vac advance, stock 8BA heads, headers to cherry bombs, standard 3 speed. its 12 volt neg ground.
I spent a lot of time on the road getting it to run smoothly. kept adjusting the timing and fuel mixture. timing at 475rpm is 4 deg btdc. had to restab the dizzy one tooth counter clockwise to get to 4 btdc but the vacuum advance is against the water neck and cannot back counter clockwise any more. if I have it one tooth clockwise, it almost is on a belt. carb mixture is about 1.5 turns open. sounds great at idle but when I need power to get up a hill it really struggles. it doesn't backfire or die but just doesn't have the pop to get up the hill. If i'm on a flat to downhill road i can hit 45 in 3rd. If im going the other way on a slight incline i cannot get past 30 in 3rd. any ideas of what I am doing wrong. any help is appreciated. God Bless |
Re: 8BA doesnt have power Look at a mechanical advance dizzy. Bubba/charlie/etc ...all here. less worries. It will be a lot of little things that add up to overall power.
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Re: 8BA doesnt have power If you watch the timing marks (using a timing light) at idle, then speed the engine up to 2000 rpm does it advance?
The stock distributors are not a very good setup but should do better than what you describe. Terry |
Re: 8BA doesnt have power Just to be sure, where is the distributer vacuum line connected?
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Re: 8BA doesnt have power Tinker, I will look at the mech dizzy. dont know anything about them.
Cadillac 512, it does advance so its working. I have a bosch timing light and it shows the rpms and advance. the distributor vacuum is attached to a port in the back of the carb. hmmm? |
Re: 8BA doesnt have power I'm not a fan of the original vacuum distributors, but some are. I would go with the converted Chevy. You can get them as full mechanical or with both. Full mechanical is much easier to set up.
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Re: 8BA doesnt have power JSeery, thanks. I will look into that. Bubba/Charlie know that I understand.
as to your first question, do I have the vacuum advance connected in the right port? I have another port in the carb base plate, not sure of the difference. |
Re: 8BA doesnt have power would I be nuts to go with a newer electronic MSD dizzy?
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Re: 8BA doesnt have power It sounds like you have the distributor hooked up to the proper vacuum port, and it does seen to be working from your description. I personally would take another try at re-installing the stock distributor. I have a lot of experience with them and you should not be having the trouble you are with the distributor fouling on other engine parts. Are you sure you didn't move it two teeth? Also, are you sure the rest of your ignition system (points, condenser, coil) are up to snuff? There are a lot of bad components out there lately. I would try to get the stock setup running before I would spend good money on an aftermarket electronic distributor. Contrary to a lot of misinformation out there, the stock ignition system on these engines works just fine if properly set up with the proper carburetor.
Oh yeah, the "bump" on the stock front pulley is at 4 degrees BTDC and is where the ignition should be set, not 4 degrees before it. Also, remember the old saying : "90% of all ignition problems are carburetion related and vice-versa". |
Re: 8BA doesnt have power Ypou might want to browse this thread : https://www.fordbarn.com/forum/showthread.php?t=274603. He had a similar problem and finally solved it. I'm not saying that this is what is going on in your situation, but it just shows the variety of things that can cause such problems (and their solutions).
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Re: 8BA doesnt have power Did you in fact insure that when the distributor was located with the number one position located at 6 o'clock the number one piston is located at top dead center?? (top of compression stroke)
https://www.fordbarn.com/forum/pictu...ictureid=42315 |
Re: 8BA doesnt have power Tubman has got a good idea. I run the stock load a matic & it works fine with the stock carb. Isky cam & Offy heads. 51 Merc's sugestion is on the mark too.
Love your truck !!!! |
Re: 8BA doesnt have power Quote:
Thanks, I feel better now having gotten these transgressions off of chest. I understand that there is no statute of limitations for these... Chap |
Re: 8BA doesnt have power Something not mentioned was point dwell which should be 27 degrees, and has to be verified before setting any initial timing. The timing bump on the pulley is 2 degrees BTDC and will provide good performance, but some additional advance is usually better, depending on fuel quality, altitude, driving habits etc.
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Re: 8BA doesnt have power Remove your distributor and install it so it doesn't touch anything and can be fully adjusted. Then check: firing order, condition of spark plug wires, cracks or carbon tracks in dist. cap, rotor and make sure vacuum diafraghm (spelling) is working. Do you have any vacuum leaks?
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Re: 8BA doesnt have power Thanks, all good advice (and confessions). ill go thru every comment this weekend and hope to find the issue. I do want to keep it as stock as possible. ill let you know what i find. God Bless
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Re: 8BA doesnt have power Just so we have the full picture, Trent, is the vehicle the one in your avatar?
It looks quite low, what size are the rear tires?? Mart. |
Re: 8BA doesnt have power A defective condenser will seriously affect engine power. This is because a weak or open condenser will not allow the coil to be fully charged, resulting in a weak spark at the plugs. We reuse condensers rather that rely on the poor quality of those now sold.
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Re: 8BA doesnt have power When an otherwise fine running flathead all of a sudden has not much power it can also be that the spring strap on one of the sets of points has broken. The engine will run on one set of points but not real well due to lack of dwell. Not the case here but something to keep in mind on dual point setups.
I suspect the Loadmatic which needs everything perfect to perform adequately or not on right tooth of drive.. |
Re: 8BA doesnt have power Mart, the avatar is the truck, I did lower it a few inches. the tires are 255/60R15. a little shorter than the stock tires i assume. Nice head stud removal video btw.
Supereal, I will swap out the condensor. does anyone like Napa sell good ones anymore? Deuce Roadster, its a single point Loadmatic, set to .015 clearance. I think that is correct. Ill load some photos once I remember how to do it, been a while. |
Re: 8BA doesnt have power All, just remembered another clue. when I hit the gas hard it coughs and almost dies. I have to ease into the throttle. it makes a big sucking sound. any thoughts?
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Re: 8BA doesnt have power Quote:
First try with stroke set to winter (farthest outward position) if no improvement then it may need replacement. https://www.fordbarn.com/forum/pictu...ictureid=42318 |
Re: 8BA doesnt have power I would say that the carburetor needs another rebuild.
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Re: 8BA doesnt have power Short story...
A local friend here in Indy builds some of the faster and best sprint cars engines in the country . studiess ever little detail and has a dyno for engines , all recieve a test run before shiiping etc . So hes very qualified. He bought a basket case 39 for a few years ag and rebuit with great care the engine, ignition was a helmet , that built for him. He ran the engine on his dyn and came to my shop and siad this isnt working , the engine would make 71 HP !!! I went over it with a fine toothed comb and found NOTHING that wasnt perfect!! Called Charlie ( on the forum) andhe says to me , put some csh into the carb and ship it to me. I did, got it back and my friend ( who had rebult the carb twice ) dynoed the engine and now makes 110 hp !!!!! JUst another suggestion ?????:eek::eek::eek::) |
Re: 8BA doesnt have power Are the brakes dragging ?
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Re: 8BA doesnt have power good advice on the carb. ill check the accel. pump connection. been a while since I rebuilt it (three times) and cannot remember its position.
help me find Charlie. might need his magic touch i dont think the brakes are dragging but will check. if free rolls well. |
Re: 8BA doesnt have power A think most of go to's are here..
https://www.fordbarn.com/forum/showthread.php?t=269580 Charlie I hope this is okay? I believe Charlie is dealing with some family issues. God bless. Charlie is Charlieny here, maybe send a nice pm. https://www.fordbarn.com/forum/member.php?u=1147 . |
Re: 8BA doesnt have power Big sucking sound? Like an old man running, mouth open sucking for air. thats starving
for fuel . Must have grabbed dirt or something, main jets venturies plugged or the power valve took a dump. As 51 Merc said it won't hurt to go to winter on the acc. pump I run mine there all year, But the acc. pump mainly comes into place for cold starts. Old cure sometimes, race it up put hand over carb just to about stall it. And 'sometimes' that piece of dirt may get sucked out up, by vacuum. I wrote this here many times, engine off throttle wide open and shoot shop air in each venturie you should get a good fuel mist on each side - a good good strong atomized mist. I bet thats ya problem sam |
Re: 8BA doesnt have power Thanks for all the help. ill let you know what I find out.
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Re: 8BA doesnt have power Okay, pulled the dizzy, I had #1 at 12:00 so i reworked it at 6:00 and it now starts cold without choke or pumping the gas. not sure why that would matter but it surely did. set the timing at the bump (4 btdc per Tubman) at 475 rpm. swapped out the condenser with one i took off it years ago. checked the vacuum, it has 15 psi. seems a bit low but there are not any leaks, only two vacuum ports, one for vac advance, the other at the carb base for the wipers (not installed and plugged). not sure why the vacuum would be low, shouldnt it be around 25 psi?
I tore into the carb (94 ford) and found that the jets were not matching, one was a 35, the other a 48. looked like the fuel issue. took two 51 jets off another carb, new accel pump plunger, new gaskets and really took the time to clean and blow out all passages, all was clean. oh, and a new power valve. I had 4 power valves in my parts box and two were new or unused. set accel pump stroke to the winter position. vaporizes very well from the pump nozzle (#70). Did a dry compression test and all ranged between 90-115. ill do it again wet and i assume they will even out. Still if I hit the gas hard, it dies. It still makes this large sucking sound. if you ease into it it will rev up nicely. thought maybe my electric pump was not giving enough fuel. I ran the pump by itself into a cup and had a nice steady stream of fuel. its an edlebrock pump, now and 3-4 psi. emptied the tank and put in fresh gas, no change. ill post the video on youtube and post the link so you can see it. still puzzled. |
Re: 8BA doesnt have power video of engine running. when I accelerate it sucks thru the carb loudly and wants to die. audio doesn't demonstrate this well
https://youtu.be/taB7EqcCGmM video of carb vaporizing when accelerating. seems to be doing what it should but will die if I do this quickly. https://youtu.be/igmAtT0fcqs any tips. I know I am missing something simple. hell, almost 40 years ago I put this truck together with no knowledge and drove it every day. has to be something simple. thanks and God Bless. |
Re: 8BA doesnt have power I couldn't see clearly enough in the video but do you have the correct carb base with the (can't remember the name) valve in it? It looks a bit like a power valve.
Also, probably not directly related, but why does the carb not close properly? If you suck on the pipe leading to the vac advance does the engine speed change due to the timing advancing/retarding? I'm thinking of it as a way to test the vac diaphrahm. Edit: In the second video I can't see two clear squirts of fuel from the accelerator pump. Is it working? Did you make sure the check ball in the small bore at the base of the accelerator pump bore is not stuck? |
Re: 8BA doesnt have power It's all a matter of perspective. If you are a "purist" then by all means suffer the issues with the old Ford carbs and the load 'o' matic dis. Parts to service them are becoming increasingly difficult to come by AND much of it is repop from offshore of dubious quality.
Chevy distribs converted over to electronic are the way to go OR the MSD. Many of us more interest in driving our cars are using the later GM type (50s) 4 bbl carbs. Pretty bullet proof eliminating most of the fuel issues. We've been running our 49 for 25 years with the above setup and outside of regular oil changes and greasings pretty maintenance free. |
Re: 8BA doesnt have power On the other hand, I drove my bone stock '51 club coupe for 31 years (1987-2018) without missing a beat, 94, Load-a-Matic, and all. These are simple machines to work on and I never had a problem with availability of parts. If you want a modified engine, that's just fine, but if you want good running stocker, it's probably much cheaper and easier. Sending your Load-a-Matic to "Bubba" and your carb to Charlie will be much cheaper than buying a 4BBL manifold, finding a decent small base 4G or WCFB and having it properly rebuilt, on top of having a SBC distributor converted. BTW, have you seen the prices on cores for those carburetors these days. By the time you find decent core and have it rebuilt, you will probably be north of $500. A new 390 Holley is probably a lot cheaper, even with the price of the adapter.
The reason that I pulled the stock engine in 2018 is because I had a built Mercury sitting on a stand that I was just itching to install. It's got a lot more power and is just better all around, but a stock engine served me just fine for 31 years. |
Re: 8BA doesnt have power Mart, the carb base doesnt have the valve. the ball in the accel pump is free. when I timed the engine with the vac advance plugged then unplug it the timing does change so the pull off does work. video is not clear but it squirts two nice sprays of fuel.
Gene, a bit of a purist if I can make it work. i know it can run with stock parts well and want to do this first. I have a holley 390 and edelbrock intake but just wanted to keep it stock for now. I want to channel Tubman and drive it stock for the next 31 years if I want to and upgrade it if I want to, not because I had too. Thanks for the comments. I might just get Bubba and Charlie involved. sometimes you need to go to a higher authority. God Bless |
Re: 8BA doesnt have power Thankx Trent. Good on you. I did the same (purist) for many years and Tubman is right. It can be done.
I thought about the Holly but there are many mixed reviews on them. The Holly does not take long term storage well. The metering plate and bowel gaskets dry out and you are disassembling it. The early GMs work well and are a good choice. Bubba and Charley are mentors on this board and good choices to lean on. One of them (I think) years ago did some dyno pulls tuning advance rates. Surprisingly, more/quicker killed the torque curve. Impossible to tune for using the load'o'matic. Anyways, Every time they write something I always am intrigued and marvel at their knowledge. |
Re: 8BA doesnt have power Just a side note. I really like the small base 4G's as well. I got real lucky and found a matched pair (both from '53 Olds Stick cars!) that I rebuilt for an early Offenhauser dual quad on a '51 Rocket. That was about 5 years ago. Lately, I cannot find a decent core for under $100 (on eBay, a lot more). Even small base 2G's are getting difficult to find and expensive. This led to my ill-fated project of trying to put a quadrajet on a flathead.:(
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Re: 8BA doesnt have power Trent. The 94 for the 8BA has a different base. It has a secondary port that has a special valve in it. I don't know the exact functionality of it but it is part of the loadamatic vac advance signal system.
Do you have a spare carb with that type of base? It might make a difference. I don't know. Millions of people did billions of miles in Fords of that era without having Chevy distributors and GM carbs, and ran better than yours does. There is something wrong. My cars run great on 94s but not without some dialing in. Can anybody say how important the correct carb base is? Mart. |
Re: 8BA doesnt have power From what I remember, 8BA carburetors did not have a "spark valve" (that thing that looks like a power valve that screws into the carb base). That is on later carbs (2100's and 2110's). If you do have one of those, it should run fine, if it has the proper distributor vacuum.
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Re: 8BA doesnt have power Try what Chap 52 says (,Valve timing ),,remove a spark plug and look at the position of the valve you should be able to see the inlet valve ( I think ) and what's its position in relation to the TDC mark, .You could also pull the front cover to check the marks .
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