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#1035773 - 03/02/16 03:52 AM Re: SSLance's Build thread [Re: SSLance]  
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Originally Posted By: SSLance
With the old setup, it would pull like a train out of the hole or from a dig, then just kind of lumber on up the RPM range. Now, it pulls like crazy from down low...and just keeps on pulling all the way up. laugh It is quite different than before, yet it looks the same, sounds the same and has mostly the same manners.


They say a picture is worth a thousand words - here's your dyno graph with the HT383 graph published by GM inlayed to scale. Yep,, quite a bit of difference there!!! It should feel like hitting a 125-150 shot of nitrous stabbing it at 4000rpm!!!



Original owner of 1985 SS black hardtop w/gray interior. Frame-on restoration - 406 sleeper w/ heavily ported FIRST TPI. However the 1.875" headers, 3.5" duals, TH400, Ford 9", notched frame, and 10-point cage w/swing-out bars might tip you off it's not a lil' ole 305 TPI. Other mods: 2" drop, 18" wheels, f/r disk brakes, and custom stereo system.
#1035774 - 03/02/16 04:14 AM Re: SSLance's Build thread [Re: BadSS]  
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I'm sure there is quiet a difference in performance. But the dyno at the engine shop verses GM published chart will have a significant difference in engine output. In most all cases the engine shops are quiet generous with their numbers.


Enjoy life, family first!
#1035776 - 03/02/16 04:43 AM Re: SSLance's Build thread [Re: SSLance]  
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Don't pay attention to the numbers themselves...the direction the lines on the graph are going really tells the story. It is very noticeable with my calibrated butt dyno!

Still very civilized though and cruises down the highway in 6th gear at 1500 rpm pretty well also.


Lance
1985 Monte Carlo SS Street Car
#1035921 - 03/05/16 03:11 PM Re: SSLance's Build thread [Re: SSLance]  
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Well, it's not hot rodding if you don't have to love on some things...right?

Seems my continuing battle for space on this car while trying to cram 10 pounds of crap in a 5 pound bag continues.

I pulled the headers off yet again yesterday to investigate for a possible gasket fix and found no sign of a leak whatsoever...they were sealed up tight. After some reassembly, some discussions with the engine builder, and more investigation...I discovered I could feel a rod cap contacting the windage tray inside the new Canton oil pan once the oil pan started to take heat.

It clears and is quiet when started cold, but the more heat the pan takes, the worse the feel and the noise gets. This was not present during the dyno runs, our thoughts are the pan shifted sideways just a touch when the engine was sat on it for the ride home. We knew it was close and we thought this might be a possibility when we first discussed the noise, but the header leak seemed more likely so I spent a week chasing that angle. Had I just put my fingers on the pan instead of everything else under there beside the pan, I could have saved myself a lot of time and anguish.

The builder wants me to bring the car to him because he says he has a trick way of moving the pan over a touch and cinching it back down. Sure hope it works as option #2 is lifting the engine to remove the pan and modify it or use a thicker pan gasket.

I'm frustrated yet happy at the same time that the issue is now properly diagnosed and we can continue on with a proper fix.

I've got about 200 miles on it now and I must say it is a radically different feel that what I had under there before. It looks sounds and feels almost the same until you open the secondaries up, then things change in a big way. Still getting used to it and still haven't really got on it hard as I'm trying to break the new clutch in the right way. Can't wait until I can finish the fine tuning on a quiet engine and turn the wick up to really see what she has now.


Lance
1985 Monte Carlo SS Street Car
#1035922 - 03/05/16 03:17 PM Re: SSLance's Build thread [Re: SSLance]  
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I have some special tuning I can help you with at Putnam. Especially if we're close in lap times.

#1035923 - 03/05/16 03:20 PM Re: SSLance's Build thread [Re: SSLance]  
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I just bet! laugh


Lance
1985 Monte Carlo SS Street Car
#1035924 - 03/05/16 03:33 PM Re: SSLance's Build thread [Re: SSLance]  
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#note to self... Remove shock adjusting knobs and leave valve stem caps on when Ramey is around...


laugh


Lance
1985 Monte Carlo SS Street Car
#1036151 - 03/10/16 12:51 AM Re: SSLance's Build thread [Re: SSLance]  
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Barney is back home safe and sound, tucked away in the house garage and ready to be driven...

The shop raised the engine a bit and dropped down the pan. They snapped these two pictures with their Snap On scope Camera (I took pictures of their screen, sorry for the quality).





What you see there is a piece of metal that holds the scraper. On that metal you can see where a rod nut was just touching it enough to knock the plating off in one spot.

Here is a picture that shows the scraper better



They then pushed down on the metal just a bit there where it was hitting and reinstalled the pan being sure to push it as far to the passenger side as possible before cinching it down.

The rods cleared when turning the engine by hand so they buttoned it up, put new oil and filter on it and test drove it to put some heat in it and it stayed quiet. I'm calling it fixed.

I didn't like any part of this, but they assured me that it is not all that uncommon and not that big of a deal, but also realized the noise was unsettling. I'm just glad it's fixed so I can go on with the rest of my off season projects... I sure appreciate Yancy taking care of this for me, this was much easier than pulling the engine again to pull the pan which would have been my remedy.


Lance
1985 Monte Carlo SS Street Car
#1036164 - 03/10/16 05:19 AM Re: SSLance's Build thread [Re: SSLance]  
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Good, would be good to have that problem remedied.
Assuming you are still running the GM one piece pan gasket that came with the engine. Don't know if any of the available one piece vary in thickness. I'm using the Canton one piece gasket for a two piece seal block and like it. Had the Fel Pro one piece and Canton laying aside each other, no physical difference other than color as far as I could tell. Tom's ZZ4 shortblock I believe uses the same GM gasket as your engine. We had his pan off a few times and reused the pan gasket, no leaks. You need to keep an eye on the pan sealing for a while, especially if you dump synthetic oil in it.
Happy motoring!
Bob

#1036487 - 03/18/16 02:26 PM Re: SSLance's Build thread [Re: SSLance]  
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I think I might just leave well enough alone... laugh

I have about 500 miles on the new mill now, it is running fantastic and exceeding all expectations. Now that the clutch is broke in I can really start hammering on it, might even make a video or two...

What I have been working on lately is programming the MSD box to get the timing as efficient as I can get it as well as working on the cooling system to keep the temps in a more comfortable range. Big thanks to Bob (mmc427ss) and Jabin (gmachinz) for their continued help with the fine tuning of systems.

The timing escapades can be followed here if interested http://www.lateral-g.net/forums/showthread.php4?t=48612 I think I am going to stop right where I'm at instead of advancing the distributor to 45* locked in as I'm a bit concerned about rotor phasing and cross firing with it that far advanced. I really don't see that the added gain by the additional steps will affect the way I drive the car that much, not enough to take the chance of adding additional troubles.

The cooling system is getting better, I might have it where I need it now and if not, I have one more trick up my sleeve. The car doesn't overheat, but the way it was configured...the electric fans wouldn't kick on low speed until the dash gauge went past 220*, then shut back off at around 212*. At idle, any temp over 210* or so caused a bit of an erratic idle, caused the idle to raise from 850 to 950 RPM and the AFRs got a bit wacky as well. As long as it was idling under 200*, everything just worked smoother. This is most likely carb related and I've resigned myself that I just won't get this setup to run as smooth as a EFI inducted setup. It's pretty good like it is though so I just worked on getting the idle temps down. For reference, at cruise on the highway...it stays steady at 180* without the fans running, due to the 180* thermostat.

I had my two fan switches both in the thermostat housing and had the gauge sensor in the driver side head. I moved the low speed fan switch to the passenger side head and that made the fans kick on low speed just before the gauge gets to 220* and it kicks back off between 200-210*, at idle in the garage the fans only run for a minute or so.

This is much better and the idle stays pretty stable in the garage. I don't think I ever hear the fans kick on high speed, really don't think the engine ever gets hot enough for high speed to be necessary. Now I can override the temp switches with my 3 position switch on the dash for the fans, what I will probably do during race days is use the dash switch to put the fans on high right before and right after runs to help keep the temps at bay when not at highway speeds.

If I decide it's necessary, I'll pick up a lower temp switch (like on at 195-off at 185) and put it in the t-stat housing to make the fans come on even sooner. This is a pretty easy fix and won't require draining the water again or moving any wires.

One thing I can not figure out though, and I'm sure it is carb related is the idle speed after driving the car. No matter how hard or easy I drive the car, once out on the road, any time I come to a stop light, the idle stays between 950-1000 RPM. I can not figure out what is different, or what is happening after the car is driven but it must be either extra fuel in the idle circuits or maybe extra air getting into the carb somehow, but it is constant and has been like this for a while. About the only thing I have not tried to correct this is swapping out the PCV valve. Not sure if that would affect this but I've pretty much resigned myself to live with this as well.

Like I said, most people driving this car would never notice any of this, all they would notice is this car runs VERY close to as if it actually had fuel injection. Starts are seamless, even hot starts, it can be driven right away after start up with no hiccups, it never has even the slightest of hesitations once on road...if you ask for it, it is there every time... Overall it is SWEET to drive. Can't wait to get it out on the track. My first event is an autocross test n tune April 9th.


Lance
1985 Monte Carlo SS Street Car
#1036490 - 03/18/16 04:21 PM Re: SSLance's Build thread [Re: SSLance]  
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Lance, is that locked with the programmable MSD box? What did you do with the mechanical advance?


85 - ZZ383, 6-speed, 8.5"
70 - Stock, 35k miles
#1036491 - 03/18/16 04:30 PM Re: SSLance's Build thread [Re: FrankOC]  
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That's good you're so happy with it Lance Congrats.

I would think the high idle is a slight lean condition after it warms up. Do you notice any AFR change at idle after it warms up? I know this is hard to tell as is bounces around a bit.


Enjoy life, family first!
#1036526 - 03/19/16 11:14 PM Re: SSLance's Build thread [Re: FrankOC]  
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Originally Posted By: FrankOC
Lance, is that locked with the programmable MSD box? What did you do with the mechanical advance?



You actually pin the advance inside the distributor to lock it out.


Lance
1985 Monte Carlo SS Street Car
#1036556 - 03/20/16 08:40 PM Re: SSLance's Build thread [Re: 1 Slow SS]  
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Originally Posted By: 1 Slow SS
That's good you're so happy with it Lance Congrats.

I would think the high idle is a slight lean condition after it warms up. Do you notice any AFR change at idle after it warms up? I know this is hard to tell as is bounces around a bit.


Yeah, I'm pretty sure it's some sort of lean condition but danged if I can tell where it's coming from. I've tested it with every port on the carb capped off and a brand new insulator between the carb and intake and it does exactly the same thing.

I swear the extra heat in the intake manifold is boiling the fuel inside the carb or something...the cooler the engine is, the better it is.


Lance
1985 Monte Carlo SS Street Car
#1036568 - 03/21/16 01:06 AM Re: SSLance's Build thread [Re: SSLance]  
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Hmmm, could be numerous thing.
For a PCV valve I prefer to use the Delco ones, CV774C, it has the plastic 90 attached and seems to remain consistent with my engine. Being Standard Products makes most of the Delco older OEM parts for them today, "off shore", the Delco and Standard could be the same part. Being the PVC is vacuum sensitive a vac gauge to monitor what's going on will help. I've had one dangling from my rearview mirror a time or two. With a carb the vac gauge can also tell you when the primary power enrichment circuit kicks in , when the sec air valve opens, that's besides the couple things you can see at idle. A very handy tool.

Another import aspect of the PVC is the systems fresh air intake. It needs to be not restrictive, filtered, and monitored for oil collection. At WOT, 4" vac and less, due to higher crankcase pressures, more blowby, some of the blowby exits the intake, oil can come along with it, the filter gets oily. Something to keep an eye on especially if beat on the engine, oh, say an autox winding it in 2nd gear. Blowby is another one of those things to monitor on a build.

So yep, the PVC system is something to insure it works correctly.

Not that I think timing is the problem but it's easy to check. Check the timing before you go for a ride, leave the light suitable attached, close the hood, go for a ride, when the idle speed issue arises, pop the hood check timing. I've got an inexpensive Flaming River battery powered light for that purpose, one wire, looks like a flashlight, well, it's also doubles as a flashlight.

Is there any chance the MAP sensor becomes heat soaked also, could cause a voltage change, effect boost retard timing. Just fishing.

Vaccum leak. New gasket/insulator under the carb. The four bolts as snug, not killed. Brake booster, dash vac lines, choke pulloff on the carb, cannister purge, just a couple potential leaks. Pulloff, attach a long hose to it, apply vac via whatever works, see if it holds vac. When you release the vac check how many seconds it takes for the Ruggle pulloff to return to rest, 1 1/2 sec would be good.
From my experience with pulloffs and vac advance canister the quality anymore is very questionable. Had to buy 4 pulloffs to get two good ones last time.

Check to insure the choke plate has tension holding it firmly open when hot. What I've seen on these electric chokes is the crimp connection internally for power to the coil gets corroded, loose, poor connection. Can make the choke coil inconsistent. Could be when hot, less voltage to the coil, less tension on the plate. Just fishing again.

Intake gaskets. Not likely, your idle vac seems very good. They should be re torqued, in sequence, a few times. Only experience I have with Vortecs is the 4.3, head gaskets twice, but same setup, just 25% less. With any old school SBC intake bolts are something you always need to touch a few times after a build.

Fuel. Qjets do pretty good under heat soak conditions. I think you are still using a stock pump with the return, the return should be used. IMO a fuel return loop should be on every hipo carb'ed engine, there are only advantages, the only disadvantage would be having a pump that can't keep up with the demand after recirc. The closer the return is to the carb inlet the better.

Idle air bypass. When hot, idling, take a look down the primaries and see how far open the plates are. If they are open to far to get the necessary air into the engine a little A/F could be pulled from the idle transfer slots. Idle air bypass is like having a calibrated hole under the carb to allow enough AIR into the plenum, this allows the plates to close a little more and the idle mixture circuit only to contol the A/F.

The fuel level. Another thing to check, engine idling normal when warmed up, and engine hot and idling at a raised rpm, look down the primaries with a flashlight and check for ANY nozzle drip, zero drip is the only amount to have. Fuel level height and fuel pressure main culprits. 6 psi at idle is desirable, some stock pumps put out to much, another reason to bleed off some via a resirc loop. It only takes a .040" hole to bleed off about 1 psi.
Needle and seat not sealing 100% can cause high fuel level, nozzle drip. Doesn't take much stuck to the tip of the needle to allow to much fuel, especially from a pump putting out higher psi. It might pay to run a pump pressure test.

Food for thought.
Bob

#1036589 - 03/21/16 12:01 PM Re: SSLance's Build thread [Re: SSLance]  
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Have you taken a look at the throttle and choke linkage when the engine is idling high after a drive? My choke needed adjustment on my carb out of the box.

#1036653 - 03/22/16 02:13 PM Re: SSLance's Build thread [Re: SSLance]  
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Took this video this morning after a 30 minute drive

https://youtu.be/Ug3pqpTQnEo


Idle has increased to around 950 RPM from 850 RPM

Is that just a hint of nozzle drip I see on the pass side primary?


Lance
1985 Monte Carlo SS Street Car
#1036872 - 03/26/16 04:26 PM Re: SSLance's Build thread [Re: SSLance]  
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I decided that since my engine upgrade is basically finished and I had a bit of time and money left over...that I'd tackle some left over suspension projects.

My first chore was to corner weigh and balance the car again. I have not done this since before all of the interior changes last year and the aluminum heads this year. First step was to disconnect the sway bars front and rear. After that set tire pressures to race trim, remove spare tire and it was ready to weigh...fuel tank was completely full. Basically the car shed about 80 pounds with the changes above, but the corner balance\cross weights stayed in the range they needed so I didn't need to make any adjustments to the springs.

Here is the car in race trim, no driver.



With driver


and cross...



Car still has 57% on the front just a little bit less than before is all. Cross is within a half a point of the total right weight which is where Ron likes to see the cross on a left heavy car like mine. Right front could use 10 more pounds or so but that isn't enough to mess with making changes in our eyes. Overall I'm happy with it, really good to see it under 3500#s now.

So while it was on the level blocks, I decided to recheck the alignment.



Apparently my mechanic forgot to set the toe last year after making some rear ride height and caster changes...so I raced all year last year with a 1/4" toe in. Good news is, with alignment set at 1/8" out...now my steering wheel is straight again.

Then I removed the F41 Jounce bars and Gran Prix bars along with the already removed rear sway bar...in preparation for some new parts on their way from UMI.

The Jounce and Gran prix bars plus hardware weighed in at 6.76#, Ramey says UMI's new front brace weighs 9#s. I'm thinking the extra 3 pounds will be worth it.



I'll weigh the new rear sway bar against the old once it gets here and share as well.

That's it for this weekend...unless I get froggy and decide to clean the wheels up, they kinda need it.


Lance
1985 Monte Carlo SS Street Car
#1036958 - 03/28/16 11:20 AM Re: SSLance's Build thread [Re: SSLance]  
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What's the reason for intentional cross weight with a left-heavy car?

#1036961 - 03/28/16 12:25 PM Re: SSLance's Build thread [Re: SSLance]  
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Ron says that is what he has found works best to keep a left heavy car neutral balanced on both left and right hand turns. All I know is it seems to work.

I still contend that my car is faster on an autocross course with 150# sitting in the passenger seat but I don't think that can be emulated with just spring adjustments. Maybe if I put 150#s of lead under the passenger seat, we could set the cross weight up a little bit more conventional and it would work as well or better. Dan Kuhn subscribes to that theory with his Maverick and swears it works...but he is dealing with a 3000# car, not a 3500# car.


Lance
1985 Monte Carlo SS Street Car
#1036962 - 03/28/16 01:07 PM Re: SSLance's Build thread [Re: SSLance]  
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Is the car left heavy to start with becuase of the steering box and AC compressor? Can't think of anything else in the engine compartment that would throw so much weight to one side.


-Mike

F-body bucket seats, camaro console, carb'd 5.3/4L80E swap

Fastest time to date: 13.390 @ 102.42
Best r/t: 0.007 I got lucky smile

Killed a few cones too

#1036965 - 03/28/16 02:06 PM Re: SSLance's Build thread [Re: SSLance]  
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We have more weight on the left front and a bit more on the right rear with the car empty so that once the driver sits in the seat the ride height lands where we want it as well as the cross weight ends up matching the right side weight.

That is the joy of coil overs, you can make any one corner weight be what you want it to be within reason just by jacking spring into it.

A lot of trial and error went into the corner balancing the first time around, just like suspension geometry...a small change in one spot also has an effect on other spots. It took a lot of little changes up and down on different springs and constant reweighing to get it to land where we wanted.

I guess because the weight I took out of the car after was symmetrical (2 aluminum heads, 2 much lighter seats), the cross % stayed pretty close to where it was before so no adjustments were needed.


Lance
1985 Monte Carlo SS Street Car
#1036966 - 03/28/16 02:12 PM Re: SSLance's Build thread [Re: SickSpeedMonte]  
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Originally Posted By: SickSpeedMonte
What's the reason for intentional cross weight with a left-heavy car?


I thought about this more and I think this might be a better explanation.

With a way front heavy car like this, if you tried to get the cross to 50% you would end up with too much of the weight on the left rear and right front and the lateral load distribution would be much different between left hand turns and right hand turns.

When you match the cross to the lighter side of the car, the balance of LLD between front and rear is more even to the left and right hand sides resulting in a car that handles the same way in both left and right turns.

Remember, I'm a laymen...not an engineer. I'm curious your thoughts on this as one that studies vehicular suspension dynamics much more than me.


Lance
1985 Monte Carlo SS Street Car
#1037013 - 03/29/16 01:39 PM Re: SSLance's Build thread [Re: SSLance]  
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First, let me just say that I was asking out of pure curiosity. It's not something that I've thought about much.

With a front-heavy car, it's hard to get away from understeer without having other effects. You tend to stiffen the rear to push the LLTD rearward, but then that has negative effects with road irregularities. That's compounded by the fact that the rear's roll center is comparatively higher than the front's. You go around a turn and hit a bump, the rear LLT is much more drastic than the front's with increased rear LLTD and a higher roll center.

My thinking would be that if you add to that understeer tendency, a leftward bias, and you get a car that limit-understeers more in right turns than left turns. That front left tire is more heavily loaded, and it gives up sooner. I would think that adding cross jacking, which makes the front left and the right rear heavier than the sum of their counterparts, would compound this effect rather than counteract it. Applying more weight to the front right and left rear would push the car toward oversteer in right turns and understeer in left turns (balancing out the effect of a front-biased, left-biased weight)

I think I must be missing something in this case though. As I said, I haven't really thought about it much and I have no real-world experience with adjusting cross jacking and testing the effects. Ron does.

#1037014 - 03/29/16 01:54 PM Re: SSLance's Build thread [Re: SSLance]  
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Before we even got to the weight adjusting, we concentrated on getting the ride height where we wanted with the driver in the car. Remember how much time I spent getting the front geometry to match what Ron wanted to create optimum front tire contact patch in braking, turn in and roll through? I believe this is as much of a factor in cornering grip if not more than corner weight.

With the ride height doing what we want, we get the car to roll the same amount to the left side as the right side with the balanced spring and sway bar rates. This keeps the front planted equally in both left and right hand turns.

The weight jacking and cross weights that he likes just ensure that all of that work isn't undone by way too much weight loading one wheel or the other.

He asked me to do something for final fine tuning. He wants me to go spend considerable time doing figure 8s in a parking lot around a set of cones. First a bunch in one direction and then turn around a a bunch going to opposite direction. He wanted me to do this to see if there was any difference at all between the left hand turns and right hand turns. I'm not sure if I'll get time to do this as finding a parking lot large enough that will allow me to set out cones and spend time doing figure 8s in is difficult...but if given the chance I will and this will tell us for sure if we have the car balanced properly.

He did say that setting the cross to match the right side of the car will make it loose on corner exit on left hand turns. I can attest to this as this is how the car has been ever since we first set it up. It is much easier to manage this than fighting a loss of grip condition on turn in or roll thru though. It's a street car, we'll never get it perfect with 57% front weight on a left side heavy car. This makes it pretty dang good though as we've seen already.


Lance
1985 Monte Carlo SS Street Car
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