New Aluninum Heads, high lift cam, motor turns slow
#1
New Aluninum Heads, high lift cam, motor turns slow
Valve covers are on know
Ok, finnaly got around to replaccing the heads, cam, lifters, push rods, rockers, intake, and carb on my 1969 442 with a 400 big block.
Heads are the Speed Master :
Oldsmobile 400/425/455 Aluminum Cylinder Heads 188cc / 77cc Hydraulic Flat Tappet Complete Heads
Sold as a pair
Intake Runner: 188cc
Combustion Chamber Volume: 77cc
Intake Valve: 2.072"
Exhaust Valve: 1.680"
Max Lift: .615"
Coil Bind: .1.125"
Intake Install: 140 lbs @ 1.8
Exhaust Install: 140 lbs @ 1.8
Closed Sear Pressure: 145 lbs
Open Seat Pressure: 345 lbs
Cam is custom ground Erson.
228/232/.565 lift on a 112lsa
Push rods are Trick flow chrome molly
9.900 BY 3/8, 80 WALL
Roller tip rockers rated at 600 # lift.
Hydrualic lifters, Comp Cams.
Air Gap intake
Barry Grant Carb 4 barrel
Car runs as it should after starting, but is verry slow to turn over, like it is dragging, set the valves at zero lash, then 3/4 turn, would the lifter preload too much cause this, I got mixed answears as to where to set it, some say 1/2 turn after zero, some say 3/4 turn, some say 1 fulll turn.
Initial Timing is at 8 degrees before TDC, 30 total at 3000 rpms with vacume advance disonected, it is a Stock HEI ignition.
Or am I looking at replacing starter with high compression starter?
Battery is 1000 Cold Cranking Amp, and is new.
Thanks!
Last edited by barryrsmith; June 9th, 2018 at 09:27 AM. Reason: Added picture
#2
Your timing is not to far advanced, in fact, probably a few degrees to low. So thats not it.
What is your battery voltage with the engine off? Fully charged is 12.7ish volts. If you are down around the 12.4v area or below, you may have a slow starter.
What is your battery voltage with the engine off? Fully charged is 12.7ish volts. If you are down around the 12.4v area or below, you may have a slow starter.
#3
One very important thing some guys overlook is grounding the engine, I always run a dedicated ground cable made out of #00 welding cable from the neg. post of the battery to the nearest bell housing bolt closest to the starter. The cable and all of the electrics have to be CLEAN!
#5
Well it is a brand new battery, but that does'nt mean a whole lot sometimes, so I did check it and it was a whopping 11.4 off the shelf.
Its charging now.
It has two Engine ground Straps.
I am allso wondering about the alternator now as well, when I remove the possitive cable while running it dies, but will not shut off with key, IT KEEPS RUNNING,, WTF?
I did not mess with any of the electrical other then unhooking the battery and engine ground straps.
Its charging now.
It has two Engine ground Straps.
I am allso wondering about the alternator now as well, when I remove the possitive cable while running it dies, but will not shut off with key, IT KEEPS RUNNING,, WTF?
I did not mess with any of the electrical other then unhooking the battery and engine ground straps.
#7
It's An HEI distributor, only positive terminal going in is from battery?
Should it be from ignition switch?
I looked in my service manual but all they show is a points style with external coil
It wasn't getting fire when I first tried to start it, I Thought maybe a wire came off form distributor because there was no = wire going in for in cap coil, so I ran one from battery to distributor cap where it says battery, then it fired and ran, but want turn off unless I remove + on battery terminal.
Should it be from ignition switch?
I looked in my service manual but all they show is a points style with external coil
It wasn't getting fire when I first tried to start it, I Thought maybe a wire came off form distributor because there was no = wire going in for in cap coil, so I ran one from battery to distributor cap where it says battery, then it fired and ran, but want turn off unless I remove + on battery terminal.
#8
Yes the HEI Batt terminal (coil+) needs to be hooked to a keyed 12v source. Most use the IGN terminal in the fuse block. If there is a constant 12v there it will not turn off. The engine shutting down when you removed the positive battery cable may be attributed to the jumper wire.
#10
Check the battery cable connection at the battery. They should be clean and you should not be able to spin them by hand. Then start checking to see if voltage is dropping with it off. The connections should have the same voltage as the posts. Check next at the starter where the cable connects to th starter and see if the voltage is the same there as the battery, and if less then how much less. Losing a 1/10 of a volt is normal, but not a half a volt or more. If the voltage all is checked like this and shows good you may need a heavy duty new starter solenoid, if that one is used.
#13
One thing I notices was your lifter preload seems like a lot. I used to always run 1/2 turn past zero. last season I backed my preload off to 1/8 of a turn and it not only idled smoother but revved much better at the track it made a noticeable difference.
#14
It may have to do with how we detect where zero is or oil pressures. I set mine by checking for zero by spinning the pushrods for the slightest drag, but this last time I used both that method and the up and down movement to try to make sure it was at zero before tightening more. Of course some insist the warmed up running method listening for the clack when loosening it, and slowly tightening till it goes quite, and lock it is the best method. Better than this may be a mechanical flat lifter system. They are a lot easier to set, and do not get out of specs very often over a long period of time with locking rocker nuts.
#15
Battery charged to 12.7 volts, still dragging on first and second turn over of engine then spins good, will check all connectors for voltage drop, and double check ground straps, ground wires are welded on each end as well as positive starter wire.
I have done quite a bit more reading on preload, and it seems all or almost all are in agreement that 1/2 to 1/4 turn is appropriate for my cam specs including Erison Cams.
So I will back off on them 1/2 turn and see.
I set zero lash at flattest spot in center of lobe with each valve at full closure.
I thought 3/4 seems heavy, but Oldsrocket parts told me to go a full turn! Errrrrr!
It seems that from what I have read, the olds motors perform better at a less stringent preload, and yes perform better at the track with 1/4 to 1/8 turn, only thing is you need to check them after each weekend of racing. That's no big deal for me as I plan on keeping it off the track, it's just a street machine with some good muscle.
I wish I could find some chrome valve covers with the holes cut out in the top for setting lifters, I had some for a Chevy one time.
I have done quite a bit more reading on preload, and it seems all or almost all are in agreement that 1/2 to 1/4 turn is appropriate for my cam specs including Erison Cams.
So I will back off on them 1/2 turn and see.
I set zero lash at flattest spot in center of lobe with each valve at full closure.
I thought 3/4 seems heavy, but Oldsrocket parts told me to go a full turn! Errrrrr!
It seems that from what I have read, the olds motors perform better at a less stringent preload, and yes perform better at the track with 1/4 to 1/8 turn, only thing is you need to check them after each weekend of racing. That's no big deal for me as I plan on keeping it off the track, it's just a street machine with some good muscle.
I wish I could find some chrome valve covers with the holes cut out in the top for setting lifters, I had some for a Chevy one time.
#17
Battery charged to 12.7 volts, still dragging on first and second turn over of engine then spins good, will check all connectors for voltage drop, and double check ground straps, ground wires are welded on each end as well as positive starter wire.
I have done quite a bit more reading on preload, and it seems all or almost all are in agreement that 1/2 to 1/4 turn is appropriate for my cam specs including Erison Cams.
So I will back off on them 1/2 turn and see.
I set zero lash at flattest spot in center of lobe with each valve at full closure.
I thought 3/4 seems heavy, but Oldsrocket parts told me to go a full turn! Errrrrr!
It seems that from what I have read, the olds motors perform better at a less stringent preload, and yes perform better at the track with 1/4 to 1/8 turn, only thing is you need to check them after each weekend of racing. That's no big deal for me as I plan on keeping it off the track, it's just a street machine with some good muscle.
I wish I could find some chrome valve covers with the holes cut out in the top for setting lifters, I had some for a Chevy one time.
I have done quite a bit more reading on preload, and it seems all or almost all are in agreement that 1/2 to 1/4 turn is appropriate for my cam specs including Erison Cams.
So I will back off on them 1/2 turn and see.
I set zero lash at flattest spot in center of lobe with each valve at full closure.
I thought 3/4 seems heavy, but Oldsrocket parts told me to go a full turn! Errrrrr!
It seems that from what I have read, the olds motors perform better at a less stringent preload, and yes perform better at the track with 1/4 to 1/8 turn, only thing is you need to check them after each weekend of racing. That's no big deal for me as I plan on keeping it off the track, it's just a street machine with some good muscle.
I wish I could find some chrome valve covers with the holes cut out in the top for setting lifters, I had some for a Chevy one time.
Just checking voltage drops will confirm the grounds are good, if the larger voltage drops are not seen. If it does drop more then using a jumper cable to the negative post and then to the area can confirm its a ground problem if the voltage then goes up with the added jumper cable ground.
Checking the actual voltage at head and tail lights might shock you
Preload varies, by head and block materials and thread count on the studs.
#20
Fwiw I ran mine @ 1/8 turn with no issues no backing off etc etc. But I dis have the spiffy lifters from lunati that have the c clips on them so you can run them @ zero. I think they call em tru locks or something like that. My new engine has solid lifters. I found setting the valves up was much easier that with a hyd flat tappet.
I wasn't saying his issues where preload related just that his 3/4 of preload seemed like a lot.
As for the crappy cranking. make sure your intial is right and make sure your wiring is right. Them old wires fall apart inside the casings.
I wasn't saying his issues where preload related just that his 3/4 of preload seemed like a lot.
As for the crappy cranking. make sure your intial is right and make sure your wiring is right. Them old wires fall apart inside the casings.
#21
ok, tossed the timing light, it was old and malfunctioning, I turned the distributer counter clockwise until engine started running a little ruff, then moved it clock wise just a bit, it turns fine now, need to get another light of course.
Sooo, what should the initial timing be, again I get three different answears from the a search, most common is 8 BTC from what I have read.
All wires cjheck out fine, did back off preload to 1/4 turn making it 1/2turn know.
I only did one side today, but will do the other tomorrow, I didn't notice a big diff in running, It does backfire a little coming down off acceleration in park, I have not put it on the street yet, sure there will need to be more adjustments after putting under load.
Thanks!
Sooo, what should the initial timing be, again I get three different answears from the a search, most common is 8 BTC from what I have read.
All wires cjheck out fine, did back off preload to 1/4 turn making it 1/2turn know.
I only did one side today, but will do the other tomorrow, I didn't notice a big diff in running, It does backfire a little coming down off acceleration in park, I have not put it on the street yet, sure there will need to be more adjustments after putting under load.
Thanks!
#22
With an HEI, your stock timing settings are N/A because a points distributor has a different mechanical curve than a Stock HEI. A stock HEI has 18-21* of mechanical advance. I would first figure out at what RPM it stops advancing, total timing-initial= total mechanical built into the distributor. You need a timing light that's adjustable to figure this out or timing tape on your balancer, or you need to mark your balancer. If you want to be in the safe ballpark, set to 14 or 15*
#23
I would put lighter springs in the HEI along with along with an adjustable vacuum advance, I say 16 to 20 base timing, if it has the usual curve. An ignitor 3 module and Accel Supercoil are also good upgrades. Let us know how the combo runs, the 750 Street Demon is well liked.
#24
First you need accurate marks on the damper, not just TDC. Make sure the TDC mark is actually there by replacing #1 plug with a piston stop, turning engine both ways and see that it stops the same number of degrees from TDC each way.
The best curve will usually be about 36 deg. total, and 12 initial with no vacuum advance. If the curve is quick with light springs, some advance may be coming in at idle rpm, so start by spinning it up and get the total. Then see what you have at idle, again with vacuum advance disconnected.
With a real big cam, you might deliberately have some advance coming in at idle rpm, and the total around 2400 rpm. That way you can have 18 or 20 deg at idle for a better idle, while having only 12 at cranking so it will crank easily and start well. For example, the MSD distributor comes with different springs, etc. and the directions show the curves you can select.
The best curve will usually be about 36 deg. total, and 12 initial with no vacuum advance. If the curve is quick with light springs, some advance may be coming in at idle rpm, so start by spinning it up and get the total. Then see what you have at idle, again with vacuum advance disconnected.
With a real big cam, you might deliberately have some advance coming in at idle rpm, and the total around 2400 rpm. That way you can have 18 or 20 deg at idle for a better idle, while having only 12 at cranking so it will crank easily and start well. For example, the MSD distributor comes with different springs, etc. and the directions show the curves you can select.
#25
First you need accurate marks on the damper, not just TDC. Make sure the TDC mark is actually there by replacing #1 plug with a piston stop, turning engine both ways and see that it stops the same number of degrees from TDC each way.
The best curve will usually be about 36 deg. total, and 12 initial with no vacuum advance. If the curve is quick with light springs, some advance may be coming in at idle rpm, so start by spinning it up and get the total. Then see what you have at idle, again with vacuum advance disconnected.
With a real big cam, you might deliberately have some advance coming in at idle rpm, and the total around 2400 rpm. That way you can have 18 or 20 deg at idle for a better idle, while having only 12 at cranking so it will crank easily and start well. For example, the MSD distributor comes with different springs, etc. and the directions show the curves you can select.
The best curve will usually be about 36 deg. total, and 12 initial with no vacuum advance. If the curve is quick with light springs, some advance may be coming in at idle rpm, so start by spinning it up and get the total. Then see what you have at idle, again with vacuum advance disconnected.
With a real big cam, you might deliberately have some advance coming in at idle rpm, and the total around 2400 rpm. That way you can have 18 or 20 deg at idle for a better idle, while having only 12 at cranking so it will crank easily and start well. For example, the MSD distributor comes with different springs, etc. and the directions show the curves you can select.
Running the vacuum advance off of manifold vacuum instead of port vacuum will give him more timing at idle, and generally a cooler running engine around town.
#26
This is a good read to get an understanding on timing concepts.
http://www.crankshaftcoalition.com/w...EI_distributor
http://www.crankshaftcoalition.com/w...EI_distributor
#27
Thanks Guy's!
I will read the article and see where I go from there regarding the timing, the car is stating very well as of now, but still have not dropped in gear yet, had to finish mounting exhuast and bleeding brakes, hooking up brake pedal ect.
Will let you know how she runs on the Demon.
I will read the article and see where I go from there regarding the timing, the car is stating very well as of now, but still have not dropped in gear yet, had to finish mounting exhuast and bleeding brakes, hooking up brake pedal ect.
Will let you know how she runs on the Demon.
#28
Easy stuff first:
1. As stated, know 100% where TDC is
2. Total timing shoup be 36 degrees (Initial + mechanical)
3. Suggest 14 degrees of initial, and 22 degrees in the distributor, all in by 2200
4. Battery must be 100%
5. I recommend 1/0 battery cables
Strongly suggest that you do a voltage drop test when cranking.
1. As stated, know 100% where TDC is
2. Total timing shoup be 36 degrees (Initial + mechanical)
3. Suggest 14 degrees of initial, and 22 degrees in the distributor, all in by 2200
4. Battery must be 100%
5. I recommend 1/0 battery cables
Strongly suggest that you do a voltage drop test when cranking.
#29
Easy stuff first:
1. As stated, know 100% where TDC is
2. Total timing shoup be 36 degrees (Initial + mechanical)
3. Suggest 14 degrees of initial, and 22 degrees in the distributor, all in by 2200
4. Battery must be 100%
5. I recommend 1/0 battery cables
Strongly suggest that you do a voltage drop test when cranking.
1. As stated, know 100% where TDC is
2. Total timing shoup be 36 degrees (Initial + mechanical)
3. Suggest 14 degrees of initial, and 22 degrees in the distributor, all in by 2200
4. Battery must be 100%
5. I recommend 1/0 battery cables
Strongly suggest that you do a voltage drop test when cranking.
#30
Got the preload set on the other side, got brakes bled, and put it on the road as is with no other adjustments, have no idea if where the timing is at the moment, just know it starts easy and no backfiring,.
I honestly think I will take it to Bumbero's performance and let them dynu tune it, yes it will set me back a few $$$$. But think its worth it.
By the way it ran like an ape with its a!#! On fire.
I think it may have pulled the front wheels if it had more traction😂😂😂
I honestly think I will take it to Bumbero's performance and let them dynu tune it, yes it will set me back a few $$$$. But think its worth it.
By the way it ran like an ape with its a!#! On fire.
I think it may have pulled the front wheels if it had more traction😂😂😂
#31
For a heavy street car , minimal stall and under 3.73 gear all in by 2200 is too soon. I run a 3500 stall with a 3.90 i have my timing all in by 2400 . I launch on the brakes at 2400 appx. Its a street car but my definition of street aint most peoples lol
#33
Driving and racing these is different from dynos is one problem, though I do agree faster than all in by 2500-2600 is not need. What most are seeing and experiencing in the real dyno world is off idle advance timings, that wakes them up with a little more timing. The biggest problem here how to get it, without undue starting problems or having too much to soon, or using computer controlled systems on the car costing thousands more.
Another problem is its an Olds, and not a small block Chevy, Ford or Chrysler, which many have experience with that like more advanced timing curves waking them up including the BBC. Then you get into a whole host of variables on weight, compression, gearing, fuel, altitude, temperatures, launch rpms, that effects what works best in real world concrete and asphalt. Or the stop light is not the dyno.
I suggest lower initial non dragging timing to start them. Then make the timing go up at idle, by using the vacuum advance mostly in, at idle, using manifold vacuum and not a ported source. Now, at idle there is a lot of combined advance taming the idles, and running the motors cooler in the city low speed stop and go driving. The minute you mash the throttle much the increase launch timing will be there giving that quick hit of power, but quickly drop being replaced by increases from the increased spring weight timing coming on, in the distributors.
For mainly strip only or road racing this is all different. Different driving situations and equipment/parts normally above 3000. And NOW a dyno might tell you more, but an ET timer thats accurate can as well and with more accuracy. Time is what matters.
#34
I called them yesterday and they told me that for what I am using it for Dyno is a waist of money, he said they would set initial timing and total timing, adjust the Demon air/fuel mixture and idle for maximum street performance, cost - 125.00
I would continue this my self but I am limited on time.
I will find out what they end up with and post when it all done.
Thanks!
I would continue this my self but I am limited on time.
I will find out what they end up with and post when it all done.
Thanks!
#35
I called them yesterday and they told me that for what I am using it for Dyno is a waist of money, he said they would set initial timing and total timing, adjust the Demon air/fuel mixture and idle for maximum street performance, cost - 125.00
I would continue this my self but I am limited on time.
I will find out what they end up with and post when it all done.
Thanks!
I would continue this my self but I am limited on time.
I will find out what they end up with and post when it all done.
Thanks!
I agree the dyno is a waste for what you needed. If you had an adjustable rev limiter on it I might suggest no higher than 4500 for now. You might mention that to them, if it has none.
#36
ok, tossed the timing light, it was old and malfunctioning, I turned the distributer counter clockwise until engine started running a little ruff, then moved it clock wise just a bit, it turns fine now, need to get another light of course.
Sooo, what should the initial timing be, again I get three different answears from the a search, most common is 8 BTC from what I have read.
All wires cjheck out fine, did back off preload to 1/4 turn making it 1/2turn know.
I only did one side today, but will do the other tomorrow, I didn't notice a big diff in running, It does backfire a little coming down off acceleration in park, I have not put it on the street yet, sure there will need to be more adjustments after putting under load.
Thanks!
Sooo, what should the initial timing be, again I get three different answears from the a search, most common is 8 BTC from what I have read.
All wires cjheck out fine, did back off preload to 1/4 turn making it 1/2turn know.
I only did one side today, but will do the other tomorrow, I didn't notice a big diff in running, It does backfire a little coming down off acceleration in park, I have not put it on the street yet, sure there will need to be more adjustments after putting under load.
Thanks!
#37
An engine can idle pretty good with a lot of advanced timing and yet silently destroy one while driving. I can't in good conscience recommend adjusting it by ear, especially with todays fuel. I graduated from that when I was a teen and bought real tools. I like to write down my settings down so I can duplicate performance after a tuneup.
#38
Just got back in town, finished the other side with preload, hmmm, I hear a lifter tapping too loud, no clicking from valves, timing still not set with light and distributer curve yet, it does turn over good and runs decent, but still just going around the block till I get this sorted out, I plan on keeping the car and need to learn how to tune an HEI, so ordered a new timing light and springs to get the correct all in by 2600.
I have vacume gauge to tune carb.
What do yall think about the lifter making noise?
I only hear one, I am thinking about adjusting while running, that's the way we used to do it in the 70's, it's been a while.
I agree with the timing can run good at idle and destroy an engine long term, it's just an initial setting. car is still setting in garage for now.
I have vacume gauge to tune carb.
What do yall think about the lifter making noise?
I only hear one, I am thinking about adjusting while running, that's the way we used to do it in the 70's, it's been a while.
I agree with the timing can run good at idle and destroy an engine long term, it's just an initial setting. car is still setting in garage for now.
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December 21st, 2017 06:17 PM