Been through that link many times. With everything you posted. Like I said availability was limited on the vacuum can. Engine was shipped before I could find one. A lot of people run locked out timing with this much cam. The motor pulls hard with initial and mechanical. Adding the can is easy if needed and as I posted is on the list of solutions if there are any issues with it as is.

 

Hi Mako - Glad that you agree. I am very anxious to hear the results of his new motor test run, perhaps tomorrow? It will be interesting to see if he has any of the same issues I had when I went to this cam......As I mentioned mine is the "real deal" GM ZL1 cam I purchased multiple decades ago.

In addition I was running GM Valve springs initially as well, and was breaking them on a regular basis...And not due to coil bind...I switched to a equivalent double spring with damper coil (3 pieces for each spring) from Crower and never had the spring issue again.....They are stout and perform beautifully at all rpm ranges.

Regarding setting cold valve lash - I'm sure that you know this but when you are adjusting solids cold lash on aluminum heads you actually are supposed to subtract 5 thousandths from the cam spec lash setting (See Edelbrock's Website regarding Aluminum heads setting cold lash), So if your cam calls for .019 lash hot you must set them cold at .014 lash. (The opposite of cast iron heads solid lash - you add 5 thousandths) - The aluminum heads actually "Grow" when they get warmed up so the lash hot is back to .019 when they are all warmed up when you set them at .014 cold. I have been adjusting my solids cold this way for decades, no problems and no mess. This explains the radical/raspy behavior and audible sound of the engine (Sounds like a funny car) when its first started cold, then as it warms up it smooths out and vacuum increases as well.
(I have a degree'd (Fluiddamper) balancer that makes the valve adjustments very easy on my mill.

I was wondering what your vacuum reading was at idle on Elle's BB after it was all warmed up? What rpm does it idle at? This is where the vacuum advance really enhances the idle quality and cruising of my BB with this "large" solid lifter cam and "gonzo" springs.

Also what was the initial and mechanical timing settings on Elle's BB? I run 18 and 18 with 16 more initial added by the can to the motor under no load conditions. I have the vac can connected to full vacuum port (not ported). I have no pinging and the engine shuts down cleanly and cranks fine when it's hot...no problems! If he is to change the vac can he will need to pull the dizzy to change it....

I am assuming that Elle88 is running a MSD 6A or 6AL box with his 8572 dizzy, yes? I'm running a 6A (unit is 25 years old!) with mine and the BB starts right up cold or hot. This motor has so much power and torque up the wazoo....... Bottom end has never been touched since Tonawanda factory built it.....cool huh?

 

We set lash hot. .010 and .012. Inital timing is 17, advance is 21 total 38 was the best power on the dyno. Used light springs and have a little mechanical coming in early to help idle quality. Idles @ 1250. Vacuum is low, 6.5. This lobe design is different than the stock cam. We had to upgrade the springs. Comp has 2 different spring recommendations for this cam. The spings on his heads were in between the 2. They went away right off the bat and we had harmonic issues with them on the dyno. It wouldn't pull past 5500 RPM. Upped the springs to the higher of the 2 spring pressures recommended and it pulled up to 6500 fine. Valvetrain stability was solid. Didn't do 7000 RPM plus pulls to really test this engine. It is not mine and I didn't want to tear it up. I have seen dyno pulls on the ZL1 and they pull to 6500, flatten out a little then pull up higher. The dyno loads the engine different than a car and it is harder on it so RPM was limited to 6500 to be safe. It has been a while now and we did quite a few pulls and adjustments but I think the above info is all correct.

 

Thanks - Let's see what Elle88 has to say after he drives it.....

 

little time and bad weather today...but at least we fired up the engine and let it run for 5 minutes.we stopped because a issue with the tach-read after.what a sound! very different from my previous L 88 cammed engine. the motor fired immediately and idled more easily than i expected.
we stopped to try to fix a problem with the tach. it doesn't work. after some tests we found than my mech tach that worked fine with my previous OEM distributor, dosn't work with the MSD8572 because the new dizzy rotates the tach wire in the opposite direction in respect to the TI one. how to fix the problem?

 

Should rotate the cable in the same direction. The Dist is a direct replacement for OEM tach drive. There is a brass insert that goes into the msd tach connection that your cable installs into. It should be in the box of parts. I am sure this is the problem. Here is a link with a picture.
http://www.jegs.com/i/MSD/121/8491/10002/-1

 

I put the same distributor in Red- all it needed was the insert and works perfectly.

 

Your coming around very nicely !

 

no way to fix the tach drive.
the brass insert is in.
but the MSD tach drive turn CCW while my GM distr CW, seen from the front(cable turns CW and ccw respectively)
don't know

yesterday I solved buying and installing what you see in pics. I've been lucky enough to find it locally, even if I would have preferred the 8krpm type.but i was in a hurry to drive the car and can't wait.
the tach-shift light conversion was already planned ( not now indeed...)
waiting for a non rainy day to test drive the car

 

That is strange. I used this same distributor in my 63 and the mechanical tach drive worked perfect. The new tach and shift light look good. Patiently waiting for a test drive update.
There is an MSD forum. Post your issue there. They have MSD techs that will answer your questions. Could be something simple.
Edit: here is the link:http://www.msdignition.com/forum/

 

Aldo I think I've found your problem, this is taken from the MSD instructions here (page 6).


I think they mean you can remove the drive assembly and mount it the other side of the distributor casting. I don't know if this means you can use the existing drive and it will then turn the right way or whether you need the adapter they mention.

Hope that helps

 

golden ,
i think you are right. the problem is that PN8492 seems to be discontinued...I believe that my distributor has been assembled with a wrong tach gear or so...

63mako.
i look forward to do a test tomorrow. heat the engine, check everything and if weather is fine , at least a short ride around the block...can't sleep tonite :-)

 

I have one in mine and it works perfectly - no mods - Just dropped it in with brass insert and it works fine.....I did however have to move the driven gear 180 degress to get the vacum can in the correct position......I called MSD regarding this and they scratched thier heads saying no need to - but that was untrue - Forum response is usually a few days if you are lucky - LOL

Perhaps someone who had it before removed the 2 allen screws holding the tach drive to the dizzy and flipped it over? The tach drive when looking at the dizzy from the brake booster it should have the tach dirve on the right side of the dizzy (Nearest to the firewall - furthest away from the intake manifold.....

 

ok. thanks. found the problem. on my 8572 the tach drive is in opposite position ( toward the carb ). i know how to fix it now

 

Another helpful hint regarding that brass insert, it can easily fall out of the dizzy when you pull the dizzy or work on the drive so - put some chassis grease on the insert and shove it back in to the dizzy and it will stay put! Ask me how I know!......LOL

 

ok .
where to start... here is the video

http://www.youtube.com/watch?v=k2D7cABytzg

we had the engine on for about 1/2 hour and we have been more focused on various checks than performance.
I had a 2-3 miles ride around a couple of free town streets, rev till 3-4k or so...
what to say ? the engine is a beast ( but i already knew that , my former engine was not so far from the new mill : L88 cam,11.5:1 CR with closed chambers...but lot lot of problems ). the new engine runs great and without issues, it stays strangely cool , the engine bay cool and the temp gage too ( 180F tstat and not cold today). I think due to the very fast mech timing ( all in at 1700rpm ) and proper jetting.
the best thing I can say is that during my short ride I didn't care about the engine and I was focused instead on the troubles with brakes ( too low vacuum ) and hard steering ( went to manual steering from power), but i will discuss these matters in other threads...
the low speed driveability is a bit less critical than my former engine, cam stall between 1500-2000 rpm , but the new engine behaves much better .the acc pump cover the hole nicely now.
a blast to drive
I hope weather will be nice soon.it will rain in next few days

 

Seriously high performance street engines are really quite the puzzle, but it sounds like Kevin has done a nice job for you. Look forward to a full report when you unleash that monster.

As for the those driveability issues, once you address the low vacuum matter I'm sure you'll be very happy, and you did move the outer tie-rod ends to the far rear hole on the steering knuckles, no?

 

not yet.
is it enough to have a usable manual steering? or just little difference?
I love the tight steering now after getting rid of power steering ( and +20lbs less on the front) when i gain speed. I feel a lot safer and car under control now.but the steering effort in slow turns is very high, I don't care too much about the parking troubles.

hey guys.
don't expect to hear from me a "power-performance" report about the new mill, because , how to say , that's not a drag racing car where power and acceleration is everything.
what i asked to Kevin was : usable , reliable power in a vintage (l88) design for fast road use. my first short ride says that the target is achieved. My main concern now is that the engine will keep it's performance in the time without issues with cam lobes, valve springs getting weak , excessive carbon build up, valve lash that goes out of adjustment...and that will stand good rpm operation without issues and staying cool. I have 4.11 rear end and rpm are always on the high side , also at low speed.
of course it's not an easy engine and requires attention but i want to focus on how to use that power now ( chassis, suspensions, steering improvements) and to do this I need the engine to work strong,reliable, stable...
I hope to be back soon with a report at max rpm ( I want to see if the new exhausts are not too restictive . Hedman 2" , 2.5" pipes, magnaflow)

 

Hi

Get writ of this PB and modify to non assisted brakes, meaning , install a manual master cylinder and forget about the vacuum.

Or install hydraulic assisted brakes.

I am driving a non assisted car and can stop the wheels at any speed.

Doesn't take as much force as you would think, just some experience, specially if you normally drive a modern car and only occasionally drive the Vette with non PB.

I can't wait anymore for spring time, this winter is far too long cold, still below freezing temp.

Rgds. Günther

 

yes I was thinking to manual brakes too...but need time to get a manual master cylinder here.
as quick fix , would it work if I connect the brake booster to the vacuum reservoir (now connected to the headlight -wipers door system) ???
or should I expect strange phenomena when applying brakes? lights pop up by themselves, for example?