Projects Cutting my Hotrod Teeth (57 Chevy Budget build/revival)

Try a size smaller rod. Then if that makes it a little better go another size smaller. If going smaller fails try going bigger. I hate the edlebrock carbs with a p***ion for that reason. Percys Adjust a Jet is the best thing for a Holley.

 

Yeah I’m thinking smaller diameter rods, or larger diameter jets makes sense because, unless I’m not understanding carbs correctly, that would richen up the mixture, especially when the secondaries are open all the way at WOT. Seems like it’s an off idle mixture issue in my opinion, just because I’ve tried pretty much everything else I know of.

 

can you borrow a known ok carb from that hoard? just as a trial

 

So last night, I swapped out the primary metering rods for the thinner ones I have in the kit. Happy to say, it definitely helped a lot! I just drove the car for about 25 minutes with lots of hard acceleration from stops. Plenty of WOT runs. I got a single pop out the carb the whole time and it wasn’t as extreme as it has been. Since it’s still not perfect, I think next step is a jet swap too, to give it just a liiiiiitle more fuel at WOT.

What I think has been happening from my limited understanding, is that when the carb transitions from idle to the primaries, or primaries + secondaries, that 1/2 second transition leans out the carb enough for the motor to backfire through the intake. I don’t think the timing has anything to do with my particular issue.

 

Man it puts a smile across my face hearing the motor roar as I bang through the gears. With these mufflers it sounds like a real hot rod! Which I guess at this point with the amount of tinkering I’m doing with it to get more power, it pretty much is!

 

If it were my hoard to pick at, sure. Though this is my good carb

 

Hmm, I wasn’t expecting to find what I did with the jets. The fronts are actually already bigger than stock, but the secondaries were some older Carter jets that looked to be a tad smaller than the primaries. I couldn’t even read the stamped numbers on the castings, and they didn’t line up with anything in the Edelbrock book whatsoever. I ended up adding the next size up from the chart in the Edelbrock manual, and I’ll go again this afternoon. This carb was generously given to me by another hamber several years ago when I was having issues getting the car to idle with the old quadrajet, and it had already been on a car at that point and tuned to the previous engine. That’s to say, it’s really a mystery carb that I’m having to adjust to my setup as I learn more about how this all works, and how my engine runs off idle.

 

After you change one thing and run it, check your plugs. Learn how to read them and adjust accordingly you do not want it running too rich or too lean. Find the sweet spot and run with it but make one change then read the plugs. It will save you in the long run.

 

Yeah, I have to keep reminding myself to make one change at a time and if it doesn’t help, put it back how it was. My plugs had been in there for the past 5 years or so and so reading them was basically useless. I also wanted a bit of a higher heat range plug since the ones in it were not able to burn off the carbon from it idling in my driveway. I just threw in a new set of champion copper plus without resistors and made a run, and it performed great! Idle seemed better, and when I laid into it, I didn’t feel that hesitation, and I didn’t hear a single spit the whole time. Got back and just checked one plug for now, but it looked pretty clean. Only time will tell if it stays that way, but I think the combination of bigger jets in the secondaries, along with thinner rods in the primaries has done a whole lot of good! The new plugs couldn’t have hurt either!

 

The fiancee wanted to go run an errand and I convinced her I’d drive but we gotta take the Chev

It performed flawlessly again, that is no backfiring or stumbles, and after the motor was cool I pulled a few random plugs and they looked really clean! I did notice my oil level was pretty low earlier. Gonna have to keep an eye on that, but given that the rear main seal, oil pan gasket, and timing chain gasket all leak, it’s not surprising I was low. Hopefully it leaked out instead of burning!

At 20 yrs old it seemed like a great idea to not spend any money on those pesky gaskets and just throw the motor in. Now that I’m a bit older, it seems like such a stupid idea to not even pull the oil pan while I had the engine out of the car.

 

Perseverance. Consistency pays dividends. Keep an eye on the plugs for a while to make sure it is not running too lean. If it starts to get hot with warmer weather coming that can be a lean sign too. You are making progress.

 

I’ve been driving the car a whole bunch the past few days, so much that I stalled my daily when I let the clutch out the first time yesterday because I wasn’t used to it being so light!

The backfiring issue seems to be either gone or almost gone. Turns out my issue was mostly in the secondaries. With bigger jets in them, and slightly smaller rods in the primaries, it has had just that one very minor spit out the carb.

I noticed 2 things though that are a bit concerning…

1. If I accelerate hard from a stop, or punch it while just cruising, the motor revs up, tach shows the RPM rising, but it takes the car a couple seconds to actually catch up. Its like it takes it a moment for the power to actually reach the wheels. I would say if it was an automatic it might point to a slipping trans, but since this is a stick, and with a brand new clutch, it doesn’t seem like that would be the case? Any other ideas?

2. Again if I punch it from a stop, I’ll get a bit of thin, light grey, just about white smoke out of the exhaust. It goes away once I’m actually speeding up, but if I look back after accelerating quickly from a stoplight, I see it. Not sure if it’s just a bit of oil getting past the valves which are almost certainly not in the best condition?

 

smoke past rings on acceleration-past valves on decelleration..

 

I do, though it doesn’t feel like that inch actually moves the clutch at all

 

Got it, okay yes then I’d say I do have about an inch of free play. The pedal does feel like it has fully disengaged from the pressure plate when this happens, and I have even experienced it with my foot off the pedal completely.

 

It sounds like that inch of free play is how it’s supposed to be when adjusted correctly, at least according to a thread I saw on the trifive forums. I will say that the pedal itself doesn’t come back to the fully “up” position on its own. It comes off the pressure plate, but to bring the pedal up any further, I have to use my foot to pull it towards myself. This however doesn’t seem to make any difference whether the pedal is right at the point of contacting the pressure plate, or pulled all the way up past that point. It doesn’t seem like the clutch could be slipping since I can’t feel any resistance on the pedal when I have fully let off. If I try to dump the clutch though I’m not able to get any wheelspin, just the motor reving up and then the car moves off the stop as if I gently let off the clutch.

 

The clutch also came as a kit with the throwout bearing and clutch fork, so it shouldn’t be because the parts are not meant to work together, because it all came out of the same box…

 

Hmm, I have a thought and it’s not a good one…

I know my rear main seal leaks. I wonder if the clutch is oil-contaminated…

 

Thinking more about it, it seems like the problem started happening after I put the flywheel cover back on the bottom of the bellhousing. I just pulled it back off and there’s definitely oil dripping into it. Whether or not the clutch disc was affected by this is difficult to say. I can’t really get a good look at it without taking it all apart. For what it’s worth, it looks dry on the clutch side of the pressure plate…

I think tomorrow when the car is cooled off, I’m going to spray a can of brakeleen up onto the flywheel and pressure plate, then take it out on a back road and do a couple clutch dumps.

Why oh why did my dumb*** 20 year old self think saving maybe a total of $30 on gaskets for this engine before putting it in the car was a good idea at all?! Kids are idiots!

 

Yeah, if engine is revving up and you’re not going, pp isn’t holding. Well, it wants to, but I thing you’re on the right track with the oil leaking o. It.

 

Put a return spring either on the undercar or under dash linkage. Somewhere to fully pull the clutch pedal fully up. With it slightly depressed it would be the same as "riding the clutch". On big truck transmissions you have two functions for the clutch pedal. Fully depressed applies the trans brake so you can get it into gear without any grinding. Fully minus the last 1" permits shifting or stopped at a stoplight. On big trucks clutches are only for starting and stopping. Shifting once moving is done by engine RPM's with some up to 18 speeds with no clutch pedal involvement. Riding the clutch or it not fully releasing (coming to the top) could be what you are experiencing and with a quick trip to the hardware or parts store could cure it. Don't over think situations without eliminating the simple stuff first. This car is after all over 50 years old and you used old parts that are probably worn.

 

I believe there is a clutch pedal ***ist or return spring on Tri-fives. Maybe yours is missing?

 

There is. I run without it. But I do have a spring to pull the pedal back up only.

 

I think you’re right. I had a look under the dash and the pedal seems to be missing the spring and even the hooks for the spring, so I will have to get creative.

 

Hmm turns out the spring was just higher up there than I expected. So I do still have the return spring, but that leaves the pedal 1 inch below it’s stop. I’ll see what I can rig up.

 

Read up on how to properly set it up. It serves two purposes. 1 is pedal ***istance when applying the clutch. 2 it holds clutch pedal up upon return for free play gap to be present. Especially keeping the throw out bearing off the clutch fingers.

The reason I removed mine is because at extreme rpm the clutch pedal would stay down on the floor even when though my foot was completely off of it.