Hey everybody. I posted a couple weeks ago about a fuel problem and solved it with just a higher psi pump and a regulator, now of course I have another problem. It sounds timed right by ear at idle. It idles abnormally high, 1200, and idle varies and doesn't have a real radical cam. The damper is so far off the timing light doesn't catch my degree markers which may just be that when I stabbed it it 1st cylinder wasn't all the way compressed. Ok, now on to the real problem. When I put the car in gear it backfires A LOT. It backfires nasty and often. Timing right? Do I need a different advance spring? It has a heavy spring on right now. It doesn't rev up worth a damn in gear I can't get it past 3,000 it's got less power than a four banger. Another odd thing is when I decelerate I hear an odd kind of turbo-like noise I've never heard before, I don't actually have a turbo. Could this be a vacuum leak? Any ideas would be greatly appreciated!
Well, first you'll have to get back to us with what your vacuum is at idle. I do distributor timing, and there's a LOT more to it than just changing springs. I have never seen a distributor that was within limits, and yet I rarely need to change springs.
This sounds like one of those back to basics problems. If your balancer is off so far that you can't see it, you will never be able to get it right. Over at ford strokers dot com, there is a very reasonably priced balancer for your application. After you get a new balancer, you will be able to set your initial timing, and then, use a vacuum gauge to get your carb dialed in. If you are going to enjoy your classic Ford, you need those two items, a timing light and a vacuum gauge. Not just you, but anybody that wants a classic.......
Exhaust Backfire or intake backfire ? I would back up to the basics. Find Top Dead center. Then look at your timing marks. The pointer should be on 0. If the pointer is not on zero make a new pointer with masking tape on the timing cover. ( Make sure you unhook the vacuum advance. Set your timing to 11 degrees to start with. At 11 degrees it should start fairly easy. and Idle well. If you don't have a timing light. then use this trick. Once you find top dead center make sure you have the rotor pointed a plug wire 1. Now from hear move the crank. To 11 on the pointer. Go back and move the distributor until the rotor is pointing at 1 again. Lock it down ad give it a try. The motor should start and run smooth. It may not be advanced enough but it should idle well. If it still runs poorly then your problem is probably not with timing. it is probably with the carburetor. Also if your vacuum advance is plugged in then you will not see the timing mark because the vacuum advance changes you timing so far the it is off of the markers.
I don't own a vacuum gauge so I will need to get one of those. When I timed it i did plug the vacuum advance and it was pretty far off the timing marks. It is definitely an intake manifold backfire.
First things that come to mind are in this order. Timing way off. Way to rich on the fuel Burnt Valve I would find Top dead center and start from there.
+1 on checking the firing order. What cam are you using in this engine? What is your current firing order? There are 2 firing orders for small blocks depending on the cam you are running. This would explain not being able to rev it and no powere in addition to backfire etc...
Oh wow. There's two different firing orders? I had no idea. I've been using 15426378, it was written on my old intake manifold. I've got a brand new engine and was advised by the builder to run it rich for the break in. I can't imagine its a burnt valve but I guess I don't know. My cam is a comp cam XE274 it's 224/232 duration.
And about finding top dead center, i rotated the engine at the crank 'till 1st piston was at it's highest point and I think it was approx. 18*-ish left of TDC. It's a 347 by the way, if that throws things off.
It shouldn't change the timing unless it has a custom cam and it has been degreed. I agree on the firing order. They may have used a 351W cam in it. That is why you see 2 different firing orders. Also the HO version went to a 351W Firing order 302 non HO 1-5-4-2-6-3-7-8 firing order 302 HO and 351 use the 1-3-7-2-6-5-4-8 get the motor to TDC and put a mark on the timing cover at the point where zero is. Then time it from that mark. If you have stock timing then you should be able to get that mark at 11 degrees and it should run good. If you still have issues. Try the other firing order before you do anything else. Also if you are running a Holley carb you may have blown the power valve. But even with a blown power valve you should be able to get a decent idle.
Ok, thanks. It's a roller block but I can't imagine its an HO, and I'm running a speed demon. I will give all that a try and get back.
