~sigh~ .. Ok, first, one needs to approach things methodically, instead of shotgun approach or stabbing in the dark. Also need to note the changes you make, and any differences those changes made. Troubleshooting 101.
When it comes to impeller clearances, EVERY water pump needs to have the impeller clearances checked upon assembly, and if it's a GROSS discrepancy, then it certainly needs to be corrected. Because of tolerances in manufacturing of pumps, housings, how far the impeller is pressed on the shaft, etc, are all over the place, which directly effects the clearance. You can get lucky, and in a lot of circumstances the clearances are fine, but, it's always good to check. And just because you clearance it once, when you change a pump, you have to recheck the clearance. Changing the gasket can have an impact, need to choose the same thickness gasket next time, so here again is a good time to be taking notes.
IF, if you are suffering cooling issues, and nothing you do seems to correct them, then checking the clearance is one step in troubleshooting the issue. In this case though, it was running cooler before a change was made, so IMO, the pump clearance isn't the problem here. If it were, it would be hot all the time. Just trying to approach this logically.
A fan can block air flow on the highway and not at idle. Blade design, shroud, etc, can all effect flow across the core at different speeds. It's best to have a shroud design that has pressure reliefs if the area of the fan doesn't cover 80+% of the core.
Another thing, running an electric fan over like 50 mph does nothing for cooling, and it can block more flow than not running. As an example, if a fan moves 3000cfm, and at 60 mph air flows through the core at 5000cfm, where does the rest of the air go? (don't ponder that too hard, it's just an example)
"I changed from a Holley DP to a brand new Cliff Ruggles Qjet and also started messing with vacuum advance. This started sending my engine temps soaring and my oil pressure plummeting. "
Ok, engine water temps do effect oil temps, which in turn does effect oil psi. But. There are still times where oil temps are going to rise, like extended periods on the highway. And unless there are other factors, oil temps will eventually be in a 'range' while in operation, and it shouldn't be enough to drastically effect oil psi. My understanding there was a gauge issue that caused the oil psi inconsistencies in the other post, but I would have to go back and reread, memory isn't serving me as well as it used to!
A real quick comment when it comes to carbs. You can't have someone 'setup' your carb to your engine's exact 'specs' and expect it to work perfectly the moment you bolt it on. That's not how it works. It can be very close, but it's ALWAYS going to need minor adjustments, there's just too many variables.
So what does this leave? What has changed that made a difference in your cooling concerns? Timing.
" I can't hot-start the car with more than 14* initial even with my mini starter without lots of kickback."
Ok first if your mini starter doesn't turn that engine over at like 14 or 16 degrees of initial timing and it's dragging or kicking back, you have electric issues or a bad starter. Check the cables, connectors, load test the battery, etc, go over the starter system and make sure everything is up to par. Crappy battery cables or a crappy battery is my guess on your setup, sounds like you would have taken care of anything else in that system, have pretty good attention to detail. Put a remote sol on it too which is a good idea anyway. You definitely have a hot start problem in the starter system.
So back to timing and the curve. I'm thinking that engine may need a lot of lead, maybe chamber design, SCR, intake, whatever, but giving it the benefit of the doubt. Give it to it then. Use as much initial as the starter can handle. That of course is taking into account the system is up to par. I'm guessing 16 - 20 isn't out of the question, and to a mini starter that is cake. Increasing initial means you have to limit total, so keep that in mind. The total max should be one of the first things determined. Once you have initial determined, total determined, then it's just rate you have to deal with. Once that's done, THEN do vacuum. Give it as much as it wants/can take until you have ping, then back off. The areas you should use for testing that, which is while driving by the way, is like with 2 people in the car, full tank of gas, and going up and down hills.
Usually, when you throw more timing at an engine at idle, the idle speed goes up, meaning you have to adjust idle speed. I haven't heard you comment on any changes to idle speed being made through all these changes, are you making any? And also, going up 100 rpm isn't a bad thing, and can also help some with idle temps. Most of my cars idle at 900-950 to give you an idea. How are you checking rpm? (since it came up)
I'm still not clear on whether or not the numbers you're getting with your light are right, still sounds like something is askew. I noticed you don't have an HEI module in the dizzy, so guess you're running an MSD or similar box? You know some timing lights don't work right with some boxes, right? Maybe take a pic of your timing marks too. On the timing cover. Tell us what kind of box you have, and the settings on the box.
.
__________________
.
1970 GTO Judge Tribute Pro-Tour Project 535 IA2
http://forums.maxperformanceinc.com/...d.php?t=760624
1971 Trans Am 463, 315cfm E-head Sniper XFlow EFI, TKO600 extreme, 9", GW suspension, Baer brakes, pro tour car
https://forums.maxperformanceinc.com...ght=procharger
Theme Song: http://www.youtube.com/watch?v=7zKAS...ature=youtu.be
|