Can you take some pictures of under your hood, in particular your fuel line set-up to the carb? Also, have you considered buying or borrowing a wide-band set-up? Maybe you mentioned this, but did you drop your exhaust and try it? I really feel bad for you. Keep your chin up.
Let's see.... pull the old springs, rearrange my schedule to drive 30 minutes to my engine builder, drop off the springs and wait a couple of days until he gets me the info, then rearrange my schedule again and drive 30 minutes back to his shop to pick up the springs (be they good or bad), then either put them back in or replace them. Car down for about a week. OR Call Greg Gessler and have the springs delivered next day for $145. Car down for 2 hours and the answer was available almost instantly. I charge my clients $100 an hour labor so in my book the time savings far out weighed the cost of the springs.
I know a lot of cars that run a lot faster than 12.99 that are running 3/8" fuel line and a mechanical Stage1 pump with no problems. Something changes as I do WOT runs that makes it just lay down. It sat for 20 minutes this afternoon, then on the 1st run after starting it back up it pulled right to 5500. One minute later it layed down on the next WOT run. What the hell could be different???
Can't drop the exhaust... shorties. It has done this before and after I changed my underhood fuel delivery setup. I can post pics if you think it would help. Air temp was low 60's today. Water temp never got over 160*. As for the O2 setup... it would be a lot of effort to find one then weld in bungs, then hook it up... as a last ditch effort I suppose it could help. I'm starting to think I have a wiring problem under the hood.
Does your car require a vented gas cap? I know another dorky idea.o No: I've had several beers this afternoon.:beer Bob H.
Me too, Bob...I'm trying to drag out all kinds of hair-brained ideas tonight, beer fog can sometimes result in creativity that we might not have otherwise. I don't even know where the term "hair-brained" came from, for God's sake. Devon
To rule out the factory wiring positively I would run a jumper wire from the battery right to the coil with the factory stuff disconnected and see what happens. Also you don't have any MSD chips or rev limiters do you in your system do you?
Try running with your gas cap totally off a few runs .....this is going to turn out to be something really weird.....do you run any kind of return line back to your tank ? Vapor lock ? And ps I am with you my 288-94h is the clackiest valvetrain cam I have ever run...almost sounds like rhodes are in there and my preload is correct....J
I like the vapor lock possibility. That is a problem that only occurrs at temp. I would look into that Yards. Would be an easy thing to eliminate
Vapor lock? Doesn't that only happen when the ambient temp is HOT and the car is running HOT? How long has this been happening? It's the first I've heard of it.
I have an MSD 6AL. 8000 chip. The MSD gets its power right from the battery. But it ran the same with a different distributor and a Stinger S4 ignition. I suppose we can put a points distributor in it and see. I'll add it to the list. Thanks John.
Will removing the gas cap cure vapor lock? Won't an electric pump prevent it? My car has no return line (not on a 69 Riv) and plumbing one ain't gonna happen (how would I attach it back into the tank?). Most likely scenario is I'll pull it off the road in a week and pull then engine and take it to a dyno. After 20 or 30 WOT blasts we'll see how it runs. At least we'll know if it is an engine issue or a "car" issue. It'll get me a jump on replacing the cracked frame sections and the leaky rear main.
For EVER. I always thought it was the crappy little Carter fuel pump just not keeping up. I never wanted to go through the effort I knew it was going to take to swap to a new-style fuel pump (and it WAS an effort! It is TIGHT back there!). But I got a bug up my butt to see what it would run when I could wring it out to 5500 RPM for each shift point. So I decided to do it. Lo and behold it wasn't the fuel pump after all. Jokes on me.
Ok, mine and Tyler's first thought is the tranny. You don't think it's the converter, but could it be something in the tranny? Do you not get any backfire or engine sputter when this happens? Just off on power? I had a bad converter once, and the engine would not pull through where it should have and toasted the tranny with it. It would run and shift, but was way off on ET. Tyler had similar issues on his race car earlier this season. Hope you find it.
I'd take it to a chassis dyno. Think it would better simulate your conditions plus what if the problem is external to the engine itself? Just sayin'.
On Saturday we'll do electrical tests and make sure the alt is putting out the right voltage, that I have a full 12 volts at the fuel pump, yada, yada. Maybe even a compression test and leakdown test. After flushing huge $$$ this last week on fuel line, fittings, filters and fuel pumps my coffers for building a new engine should I need one are thinning out.
Valid. But would a trans/converter issue come and go like this? That's why I'm thinking engine dyno. But I have an odd feeling it would run fine on a dyno. I am convinced it is in the car. Possibly trans or converter. I doubt it is fuel or ignition as that's all been changed and made no difference. I have a used trans I could throw in it. I think I can also borrow a converter.
