Well, now I'm really confused. Last night, I received my 50cc accel pump upgrade kit and installed it. I also upped to a size 45 accel pump squirter and put on the super aggressive brown cam. Adjusted it until there was a good, solid stream the moment I blip the throttle.

It still falls flat on its face lean as soon as I push the gas!

That's a crazy amount of fuel.

Yeah, I upped the compression and opened up the head, but this is still a 300 cubic inch engine.

That'd be really nice if that's all it is. Just needing some extra oiling. At least for now to get rid of the noise. I can save up for a rocker arm upgrade later, but right now, I wince at even driving it due to fear of hurting something.

Honestly, as far as I can tell, it is getting fuel. New fuel pump, new fuel filter, and my O2 meter shows it's plenty rich.

It has more issues at lower RPMs than it does at higher RPMs (where it would be flowing more).

I do wish I had a fuel pressure gauge in the cab though.

The carb came right off my old engine and I plopped it on the new one, so a couple of days at most. It did sit for a month or so before I sent it back to QFT, but I've been driving it for a few months since then. I imagine I would have noticed an issue before now, if that was the case.

I might try that this weekend. In the mean time, I am going to try to just way overjet the 450 (like size 60s or 62s) and see if that helps. I also have some smaller air bleeds to let in less air.

I'm really starting to think something is up with the ignition. My issues are much more prevalent at lower RPMs than at higher RPMs. After around 2500, it really wakes up. Below that, it's sputtery, sounds like a helicopter, bucks, and struggles. It's getting a ton of fuel, so I'm wondering if it's just not firing right. I just find it strange that with the same bolt-ons, it drove like a champ just a week before I fired this engine up. What would have happened to it? But, anything's possible.

I'm going to first swap the spark plugs from the old engine (maybe I got a bad one?) Then, my DSII. Hopefully something turns up.

That's what I'm thinking. I can feel there's a beast of an engine under there. I just can't seem to coax it out. Once I do though, all the struggle will be worth it.

And yeah, I poured fuel down the line into the carb until it showed on both fuel bowls before firing it up for the first time.

This is another case of it working perfectly right before I parked the vehicle and swapped engines. It also really does mirror how the vehicle is behaving. If I'm cruising easy down the road, it's a steady 14 - 15:1 AFR. I've it's falling on its face on take off, it shows way lean. If it's acting erratic, the AFR is erratic. It seems spot on.

 

Run the timing where the engine wants it, whatever it turns out to be. If it spark knocks, slowly back down until it quits. Are you sure your timing marks are accurate?

Also put the carb jets somewhere around 58-62. Being bored out you are over 300 ci, and you have a larger cam and ported head, letting a lot more air through the engine. You have to make up for that with jetting.

 

I ran a Summit 600 VS with 67 primary jets. My engine loved it. I have larger valves like AB, but milder cam and less porting.

 

He may need to just run the fuel line directly to the intake...lol

 

Some good news.

I swapped the DUI ignition out for my old DuraSpark II. I've wired both so that they're interchangeable and it only takes about 20 minutes. Tossed it in, turned the key, and it fired right up. I took it for a test drive and even though I could tell the timing curve wasn't ideal, and the carb wasn't 100% tuned, it was much much better!! Some lean spots here and there, but it did not have that helicopter-like sputter when I try to take off, and it didn't have the surge/buck when I pushed on the gas. I'm going to give it a few days and some more test drives before I get too excited (been there, done that), but it looks like something happened to the DUI. Maybe I fizzled an ignition module or the coil? I dunno.

I also swapped the spark plugs out of my other engine.

If all seems well, I'll put my new plugs back in. If it goes back to how it was before, I'll know I just got bad plugs and that's what my issue's been.
If nothing changes between the plugs, I'll dive deeper into the DUI and figure out what happened.

The DSII has a very stock curve, so it's less than ideal for my new engine. But, it'll get it around for now.

I'm fairly certain the timing marks are correct, but not 100%. I have a new harmonic balancer, but after I installed it, I realized that it ONLY had the timing mark for the passenger side (first balancer I've ever seen with that). I don't have those marks on this engine, and only have the marks on the timing cover. So, I didn't have a completely accurate way of getting a correct timing mark. I wish I had known that before I installed all the gaskets and covers, I'd have just lined up the two marks on the cam/crank and made sure it was completely at TDC.

Either way, I brought the #1 piston to what visually looked to be the very top. Then, I rotated the crank until the flywheel bolts were completely symmetrical (which was, maybe 2 - 3° of crank rotation).



Then, I marked the harmonic balancer at 0°, rotated it until the new mark lined up with 10°, marked again, etc. etc. until I had marks for 0 - 60° advance.



So.... Fairly certain my marks are correct, but not completely.

That's seeming to be the case.

If it comes down to it, and I put the 600 Holley on there, and if it really makes a big difference, I'll look into putting the 450cfm up on eBay and see about trading it out for a 600cfm.

https://www.quickfueltechnology.com/...57-600cfm.html

I'm just hesitant due to the amount of extra money I've dumped into this one for tuning parts, etc. Just becomes an investment after a while!

 

Hey AB. I just heard from Pmuller9, and he mentioned that 2 1/8" from the tdc mark = 36* advance. What do you have?

AB, I don't mean to sound like a snob or d...., but you have to come up with a way to test for an accurate tdc. I'm sorry, but you flunked second grade! Ha ha. I know it's easy for me to say when I'm not doing it. No offense intended.

 

FINDING TRUE TDC:
Take an old spark plug and smash the porcelain center out of it.
Thread the inside of the shell for a threaded rod.
Grind a radius on one end of the rod. Cut a screwdriver slot on the other end.
Insert a threaded rod so you can screw it into the spark plug shell far enough to hit the piston when it is near TDC.
SLOWLY rotate crank by hand until the piston hits the rod.
Mark the damper with a scribe mark.
SLOWLY rotate the crank in the opposite direction until the piston again contacts the threaded rod.
Mark the damper with another scribe mark.
You now have two scribe marks closely spaced together. The exact TDC is exactly the midpoint of the two scribe marks.
You can use #6 hole if it is easier to get at.

MARKING THE DAMPER IN DEGREES:
Measure the OD of your damper with calipers.
Calculate the circumference of the damper:
C= 3.14159 X Dia
Divide the circumference into the desired increments. Example: If you want 10 degree increments then
C X 10*/360* = desired length of increment.
Make a timing tape from non-stretchy tape, like packing tape.
Lay it out marking it off in even increments. (I find it very useful to have a 30* BTDC mark on the damper. That way If I want to check total centrifugal timing at hi RPM I can use the marks on the front cover (0-14*) and add 30* to them. It is also useful to mark the 120* ATDC point for CYL #5 & 2 TDC, and the the ATDC 240* point for CYL # 3 & 4 TDC, for setting valve lash.)
Wrap it around the damper and mark accordingly. If you have done this correctly the "0" mark will be overlapped by the "360" mark when fully wrapped around the damper. If not, adjust tape accordingly.

Example: If the damper is 9" in diameter then C= 9 x 3.14159 = 28.274"
10* = .785"
A piece of tape 28.274 " will wrap completely around the damper [OK, I'm neglecting the thickness of the tape - that is why I said "adjust accordingly".] Each .785" increment equals 10 degrees.

If you do not have a suitable tool to measure the OD of the damper you can do this proceedure "in reverse", starting by wrapping a piece of tape around the damper, measure it, divide it into increments, yada,yada...

simple

Moderator, Please make this a sticky somewhere. The subject keeps coming up.

 

No worries, it's a legitimate question/concern and is something I've been thinking about.

2 1/8" for 36° makes sense as, if I remember right, the 300 uses a 6 3/4" balancer.

6.75 * 3.14159 (pi) = 21.2" around.

21.2" / 360 = 0.059" per degree. (Roughly 1/16 of an inch.)

36° * 0.59 = 2.124"
2 1/8" = 2.125"


Honestly, though, I'm about 99% certain my timing marks are very accurate, or at least close to. If they're off, they're only off by a few degrees. Certainly not enough for a 15° difference (which is about an entire inch). I did this with the engine out, so I could very easily see down the #1 spark plug hole. I brought the piston up until I saw it stop moving and marked the balancer. Then, I continued moving it until I saw it just start to move down again and marked the balancer. The difference was not very much. I then visually used the flywheel bolts on the crank shaft to line it up and find the exact center between the two points, since they're symmetrical to the pistons (as you can see in the picture).

The marks every 10° were then made by lining the harmonic balancer up with the timing marks on the timing cover, which are already set and measured to the balancer.

That said, I do like the method mentioned by you, FTF. I had never seen/heard of this tool before, but it makes perfect sense. I am also seeing that they're available online for about $15, which isn't too bad. I'd make one myself but lack the tools to do so.

That would be me.

 

*sigh*
More incompetence. Seems to be a common theme these days.



I received the rocker arm ***** with the oil grooves. They come in packages of 4. All three packages were labelled correctly, but one of them had non-grooved rocker arm ***** in it. So.... I have 8 of 12.
Contacted them about getting the right part, and they'll ship one out, but unless it's lightning fast, that rules out that project for this weekend.

 

So, Rockauto was great and quickly sent me another package of grooved rocker arm *****, so I got all 12.

I installed them today and the squeaking is completely gone. It seems the extra oiling from the grooves helped a lot. Here's to seeing if it comes back or stays gone. Hopefully the latter!

I also made myself a viewing valve cover. Took about 20 minutes with a cutting wheel. I have to admit, part of me felt really guilty cutting up a 40 year old valve cover (it was dated 1976), but it's going to be a great tool to have. Went and got another gasket and installed it.













So, hopefully that's one problem down. That squeak was driving me crazy.

Next, it still has a bit of a miss at idle. Not sure what the deal is.

The other is that it's not very smooth... Like, it seems to be imbalanced, and anything over 2500 RPMs really makes it buzz. I can feel the everything vibrate. I don't know if it's the rocker arms, or if something wasn't balanced right at the machine shop, but I'm unimpressed.

Otherwise, swapping to the the DSII ignition solved a LOT of running issues, so I'll be pulling the DUI apart tomorrow and combing over it to see what's amiss. Who knows, maybe it just needs a new cap and rotor or something, but there's an issue with it.

 

I think it would be cool to save that piece you cut out and embed it in the sheet metal somewhere

 

I'm interested to see if the noise returns. I have the same squeak with Chevy 1.7 rockers, but not with stock. I have been thinking it was the pushrods and head clearance, but it could very well be the pivot *****.

For the miss at idle, I'd expect there to be some with those cam specs. Mine lopes a lot with the Comp 268H and 12* advance at idle. If I richen it up slightly, add the vacuum advance at idle and let it warm up, it will smooth out, but may have a hiccup here and there. It'll never be as smooth as stock.

Same issue with power at low rpm. Below 2000rpm, my truck has never been completely happy with the cam and rockers. I have made it 1000x better with Pertronix and matching coil, adding a bunch of spark advance down low and swapping to the Edelbrock 500. When the Edelbrock is rich at idle, cruise and part throttle, there is a HUGE difference in how well it runs that the Holleys could never match. With the Holleys, I needed the intake coolant plate in cool weather and don't with the Eddy. The Eddy has WOT tuning issues and boil over issues though.

For the vibration, I've had one with 2 different engines, pulleys, flywheels, clutches, transmissions and the only common part being the original bellhousing. I believe it has some runout and offsets the clutch plate at times. It seems to vibrate more at times than others that I've noticed and I can now hear the input bearings going.

 

I agree. Smooth out the edges and then sand and paint it, and I think it'd look pretty cool!

 

Well, so far so good. I installed the grooved rocker arm ***** on Saturday morning and drove it about 30 miles or so. Drove it around yesterday a little bit, and then drove it to work today. It's still really quiet! Time will of course tell, but for now I'm happy that the metal scraping chirpitty chirp is gone, and seems to be staying gone. So, I think they did the trick. If nothing else, I know what it is, and I don't have to be worried that it's some screwed up piston ring, or a dry bearing, or whatever else my imagination seems to enjoy coming up with.

The only thing I've noticed with the grooved ones is that it's about 10x as noisy when I fire it up in the morning. It sounds like empty lifters having to pump up every time (which wasn't there before I swapped these in). But after it warms up, it's quieter than it was before. I can still hear some valve train noise at idle, but it's less, and sounds kinda nice. And I can actually hear the light whirr of my timing gears as well (which I couldn't before). Also, unlike before, I can't hear the valve train noise while driving. Granted, in the cab, I couldn't hear much of anything over that horrible chirping noise, but that's a different story.

Thanks for the info on how your setup is running. That's good stuff to know. It's interesting, sometimes it'll hiccup and "misfire" at idle, and other times it'll idle really nicely. There's a slight lope at idle that I like (not as much as I thought there'd be). Good to know that maybe that's just the nature of the cam, and not necessarily an issue.

As for now, I'm holding back on my assessment for low end power. I still have not gone to WOT. I'm at about 350 miles of my 500 mile break in period and even though I'm giving it some regular spirited driving, I haven't gone all out. Plus, the chirping noise was like a mental road block that kept me from pushing it too hard.

I'm still quite confused on the timing at idle. I tuned the stock DSII ignition to highest vacuum (about 17hg) and then backed it down to about 15.5. When I checked the timing, it was nearly 28° advanced (and this is without the vacuum advance hooked up). That is a LOT of spark advance at idle. I know I haven't triple confirmed my timing mark but I know that if it's off, it's only off by a few degrees. Not 15° - 20°. 15° is nearly a whole inch on the balancer. When I can get the piston to crest and start to drop within 1/2", there's no way I could possibly be off by that much. It simply just likes a TON of spark advance. Then, add in the manifold vacuum to the advance, and it's sitting at near 45° advance at idle. That's nuts.

It pinged a lot while driving and I had poor power, so I backed it down to 12°. It stumbled and ran a bit rough, but smoothed out a lot when I hooked up the vacuum advance and now sits around 16hg at idle. It feels really healthy driving it at this setting.

So... getting closer.

 

28* sounds about right at idle for what it'll want, but that should be total, WITH vacuum advance. You definitely don't want to set base timing there. I have 12* base at idle, but with ported vacuum so it doesn't get vacuum advance just for the lope. With manifold vacuum, it is much more stable and smooth and I have to back the idle rpm down a bunch.

If you're trying to set the idle timing for max vacuum, I'd try it with the vacuum advance on and see where it likes it. I quit trying to fool around with making max vacuum at idle and guess where the timing was in the rest of the curve. I mapped it all out and set it where I want it.

​​ I also get clatter in the mornings when I don't run the lifter preload down more than 1/4 turn. When I run it to 3/4 turn, they're quiet. I've also had to do it while running to get it right because going by feel was too much room for error and left a few making noise when trying to go only 1/4 turn.