Hot Rod Forum : Hotrodders Bulletin Board

Hot Rod Forum : Hotrodders Bulletin Board (http://www.hotrodders.com/forum/)
-   Engine (http://www.hotrodders.com/forum/engine/)
-   -   Oil Restrictors or Not?? (http://www.hotrodders.com/forum/oil-restrictors-not-230957.html)

S10 Racer 03-20-2013 07:31 AM

Oil Restrictors or Not??
 
Ok guys, I have my short block together with my brand new Dart SHP block, it's going really well. One question I have is I will e running a cam driven dry sump oil system with this motor and would like know what your input is on running oil restrictors. I talked to Dart and really could not get a definate answer. The cam is a roller with Lunati roller lifters. Dart says that the SHP block is not machined for restrictors and they don't offer them but All Star Performance has designed them for this block and if running a stock oil pump, not to use them, running a dry sump or HV pump "may need to use them but not always". That's a broad answer and I would like to have a better one. The SHP has priority main oiling, what are your takes on it?

Thanks

CNC BLOCKS NE 03-20-2013 07:58 AM

Quote:

Originally Posted by S10 Racer (Post 1658611)
Ok guys, I have my short block together with my brand new Dart SHP block, it's going really well. One question I have is I will e running a cam driven dry sump oil system with this motor and would like know what your input is on running oil restrictors. I talked to Dart and really could not get a definate answer. The cam is a roller with Lunati roller lifters. Dart says that the SHP block is not machined for restrictors and they don't offer them but All Star Performance has designed them for this block and if running a stock oil pump, not to use them, running a dry sump or HV pump "may need to use them but not always". That's a broad answer and I would like to have a better one. The SHP has priority main oiling, what are your takes on it?

Thanks

Most roller lifters restrict oil any ways and restricting oil to the valve springs in not a good thing.

I would say no.

S10 Racer 03-20-2013 08:41 AM

Quote:

Originally Posted by CNC BLOCKS NE (Post 1658616)
Most roller lifters restrict oil any ways and restricting oil to the valve springs in not a good thing.

I would say no.

Good to hear, thanks:thumbup:

MouseFink 03-20-2013 09:25 AM

You did not get a definite answer form Dart because there is no definite answer. If your solid roller lifters are not restricted, use restrictors because the non restricted solid lifters will likely flood the valve train with oil at high RPM and starve the rod and main bearings.

Restricted push rods are available with .050" oil holes for engines with hydraulic lifters. I have used Comp Cams 5/16", .080" wall, chromemoly restricted push rods with full roller rockers and solid flat tappet lifters with good results. That was because the Chevrolet edge orifice solid flat tappet lifters are discontinued and aftermarket versions are difficult to find.

You could use restricted push rods with some hydraulic lifters, if necessary. Of course, you know that you must have full roller rocker arms with any kind of oiling restriction. If the valve springs run dry at high RPM, they will have elevated heating, and a shorter life, especially if they are dual springs with a flat damper. Back in my high school daze, I pushed pipe cleaners in the push rods with the old Duntov cams with single valve spring and stock rocker arms. I burned up a few rocker balls until the slotted rocker balls were introduced. The engine quit blowing oil out the valve cover breathers. In 1965, Chevrolet came out with edge orifice solid lifters in the Corvette fuel injection engines with a 30-30 camshaft.

IMO, since you have solid roller lifters and if they tend to flood the valve covers with oil, you need some sort of oil restriction and using restricted push rods is a simple and least expensive solution to the problem, without starving the rollers. Contact Smith Brothers in Bend Oregon for custom push rods. ( Smith Bros. Push Rods Bend Oregon )

snakebit68 03-20-2013 11:29 AM

s10
 
Mousefink is telling you right. I run a full roller cam from Lunati and I do run the oil restrictors. The valley has to be drilled and tapped to recieve them, and I have little complaint as they have served their purpose at 7800 RPM's. But...the restrictive pushrods would've certainly been an equally effective means and alot less expensive then the route I went. However, with that said, I am happy with the performance of my oil restrictors...which coincidentally are in a 383 stroker in an S-15. Either route will work, but one is easier and less costly. Trick Flow makes a great set of these push rods. Great input Mousefink!

MouseFink 03-20-2013 12:37 PM

BTW, Smith Brothers restricted push rods have either a .040" or .030" hole (your choice) in only ONE end. The restricted end of the push rod fits in the rocker arm push rod cup.

oldbogie 03-20-2013 01:33 PM

QUOTE=S10 Racer;1658611]Ok guys, I have my short block together with my brand new Dart SHP block, it's going really well. One question I have is I will e running a cam driven dry sump oil system with this motor and would like know what your input is on running oil restrictors. I talked to Dart and really could not get a definate answer. The cam is a roller with Lunati roller lifters. Dart says that the SHP block is not machined for restrictors and they don't offer them but All Star Performance has designed them for this block and if running a stock oil pump, not to use them, running a dry sump or HV pump "may need to use them but not always". That's a broad answer and I would like to have a better one. The SHP has priority main oiling, what are your takes on it?

Thanks[/QUOTE]

The big answer is it depends, although I'm not a fan of using them but that answer comes with contingencies.

- Street engines; never. Certainly never with ball and socket style rockers.

- Street/occasional weekend drag; never, unless using indexed oil stream on valve springs and roller rockers.

- Pro drag with inspection of valve springs between rounds; OK but prefer that be combined with index streams on the valve springs.

- Circle track/road course engines; OK with indexed oil stream in the rocker covers or from the rocker shaft or a distribution tube.

First of course is only use restrictors with solid lifters. The issue as I see it and build for it is mostly one of cooling the valve springs. Of course if you’re using OEM ball and socket rockers because of a cheap build or rules then you need the lube from the push rods for that type of trunion as well as spring cooling. Serious race engines run seriously high spring pressure this can go away quickly if the valve springs overheat. Their major source of cooling is oil spray onto the coil itself. For the most part push rod oil supply to the rocker box is inadequate for this application as it's a hit and miss dribble. Oil puddles are of no help either the spring's coils need individual attention to pull the heat off. At the same time you've got to deal with oil return management from the top end, you don't need an ocean of oil cascading onto the crankshaft. Since race type builds use high quality roller trunion rockers a lot of oil isn't required for the fulcrum, but some is required on the spring to pull off the heat it generates by its action. So using rocker covers with a built in dispensing tube to spray oil on each spring or T&D shaft rockers or whatever your functional choice is you need to be sure of adequate amounts of oil being put ON the valve springs as they certainly can get hot enough to where their temper will be affected. This mostly shows up as an inability to rev the engine up to the cam's peak power capability. Sometimes a spring breaks after being overheated dropping the valve into the cylinder, this is pretty ugly when it happens. To tell the truth, even with all of this fancy race hardware, I seldom run restrictors.

Bogie

snakebit68 03-20-2013 01:40 PM

S10
 
I didn't know they made them that way...but its good to know.

snakebit68 03-20-2013 01:53 PM

s10
 
You know...you're right oldbogie. I put them in on a recommendation from my machine shop. They told me that if I rev over 7000 consitently that my HV pump "could" pump all the oil up into the valve cover and starve my crank vitals. But...with a 7 qt pan and windage tray...on 10 second passes...seriously, how much oil could I possibly pump out of that pan unreturned in 10 seconds? Seems a bit like overkill to me. However, all I can say is that I have them and I've never lost a rod or main bearing.

oldbogie 03-20-2013 05:06 PM

Quote:

Originally Posted by snakebit68 (Post 1658717)
You know...you're right oldbogie. I put them in on a recommendation from my machine shop. They told me that if I rev over 7000 consitently that my HV pump "could" pump all the oil up into the valve cover and starve my crank vitals. But...with a 7 qt pan and windage tray...on 10 second passes...seriously, how much oil could I possibly pump out of that pan unreturned in 10 seconds? Seems a bit like overkill to me. However, all I can say is that I have them and I've never lost a rod or main bearing.

I find the problem of running the pan too low because of oil trapped in the top end of the engine is related to how you get that oil back to the sump not the pumps capacity. Typical, or perhaps common, is the blocking, partially or fully, of the rear valley oil returns to keep the oil from running back on the crankshaft. So the only return path becomes through the front of the valley then down the timing cover after there's enough oil in the valley to reach those forward drain holes. There are two things, especially in a drag engine, where the engine is nose high a few degrees where that combined with the acceleration forces tends to keep the oil away from the forward drain holes. The result is a lot of oil gets trapped top side in the valley, even the head, which might be enough to starve the pick up down in the pan.

For a wet sump, you can just plug the rear drains to the sump. Drill into the lower valley behind the flywheel/flexplate for a 90 degree fitting. Bring a tube down from that fitting (fittings if you do both sides) connect to a fitting (fittings) built into the sump. Be sure the tube (s) or hose (s) are well secured on the back of the block as you don't want the flywheel/flexplate cutting into it (them). This picks up the return oil forced by events to the rear of the valley sending it back to the pan. The fittings on the pan can be screwed in if you weld a reinforment thick enough to thread; 1/4 to 3/8 thick steel is suitable. Fancy could be AN bulk head fitting, or simply a piece of tube welded to the pan that connects to the drain hose. The return can be low on the pan to stay away from the crank. Position it so the return flow isn't directly aimed at the pump's pick up.

For a dry sump you can do the same as above or you can put a fitting and suitable length of tube through the rear of the intake's valley cover so the tube provides a suction port to the scavenage side of the oil pump.

- These techniques keep the top end from becomming flooded with oil while insuring adaquate lubrication and cooling of the working parts up there.

- It insures that the engine itself doesn't run out of oil because it's all trapped in the upper end of the engine without enough drain back provision.

- Keeps the timing case and front seal area dryer and less likley to leak from all the trapped oil trying to drain down the front of the block.

- It removes the need to allow a small rear drain back hole that slowly returns oil to the pan after shut down. When it's shut down all the oil is immediatly in the pan.

- It removes the rear intenal drain back that splashes onto the crank's rear counterweight and throw.

With a good stripper and trick pan you can do a lot to dry out the bottom end, here you have to be a bit careful not to get it too dry. A solid tappet cam can be damaged by too little oil flying around down there as well as the piston crown underside getting too hot from a lack of oil taking the heat off the crown. So you've got to pay attention when the enigne gets opened up for inspection to see what's going on with the set up. Here again you can think about specific aplication of oil where it's needed rather than trusting to fly off from the crank. Lifters that are center drilled or side grooved to put an indexed pressure stream onto the lobe to lifter interface and rods with squirt holes aimed up at the bottom of the piston can be very helpful in providing the proper amount of lubrication and or cooling right where it's needed.

I have never found with these techniques that a wet sump using a high volume oil pump can get ahead of the drain back rate to where the pump can empty the pan. For racers short on money or rules restricted to a wet sump, these tricks can extend you well into what is otherwise thought of as dry sump territory.

Much of this isn't new nor necessarily my invention, if you read Grumpy's and Smokey's old books you'll find a lot of this is there. Sometimes it doesn't leap off the page, you have to mull over what is, or often what isn't, said while looking carefully at the photos. Sometimes you discover things in the photos that are important clues that don't get discussed at all. After all these guy, as well as myself, want to win races so they don't tell the potential competition everything they know.

Bogie

MouseFink 03-20-2013 06:39 PM

GM has been trying to find a good way to restrict rocker oiling since they introduced solid lifters in 1956. By 2000 is seems like they they finally figured it out.

In 1965 GM introduced "edge orifice" solid lifters, part #5231585 (recently discontinued) in the Corvettes FI engines with the 30-30 camshaft. The oil feel hole was on the barrel of the lifters above the oil band and the lifter diameter was .841" instead of .842". GM used the same lifter in the 1968-1970 Z28 Camaros that used the 30-30 solid lifter camshaft. In 1962 GM introduced the Pontiac 389/421 Super Duty engines with solid lifters that had a smaller (.028") oil feed hole in the oil band. Oil was marginal at the rocker arms with both of those solid lifters. In 1967, aftermarket grooved rocker balls were introduced and Harland Sharp introduced his aluminum full roller rocker arms.

With aftermarket solid roller lifter camshafts, you MUST find a way to limit oil flow to the rockers. There is no factory solution to the problem because they don't have solid lifters anymore. You should never limit oil feed to roller lifters in order to reduce oiling to the rocker arms because the roller needs the oil. That leaves limiting the oil feed through the push rods .

If the push rod oil flow is limited, you must use full roller rocker arms because stock rocker arms with ball pivots need the oil flow or they will gall and seize. The grooved rocker balls helped but they were not adequate with high spring loads and high RPM. The valve springs do not need as much oil flow to reduce heat in quarter mile competition. Heat becomes factor with valve springs in endurance racing or when you are using dual valve springs with the useless flat damper. Now entered the beehive valve springs.

Then came the GM beehive single valve springs with hydraulic roller camshafts. Beehive valve springs generate far less heat and require even less oil cooling than conventional dual valve springs. The GM roller lifters have the oil feed hole on the barrel of the lifter just like the 1965 Chevrolet FI solid lifters. With lifters that have restricted push rod oiling, GM introduced the pedestal mounted rocker arms with roller trunions in 2000. It appears by 2000, GM finally found a way to reduce rocker arm oiling in order to protect the rod and main bearings.

Limit the rocker oiling and save your bearings. Anywhere oil goes downstream of the oil pump is going to reduce oil flow to the other parts of the engine. Oil that is puddling in the valve covers or running back into the oil pan and being aerated by the spinning crankshaft is wasted and does not lubricate anything.

I am using Comp Cams 15850 short travel roller lifters, Smith Bros. AH58B-7.200" restricted .040" push rods, Scorpion 1073BL roller rockers and Comp Cams 26918 beehive valve springs.....in a daily driver. The last time I looked, there was a small, but adequate, amount of oil flow over the roller rocker arms when I set the lifter pre-load, 6,000 miles and 2 years ago.. .

CNC BLOCKS NE 03-20-2013 08:57 PM

Quote:

Originally Posted by MouseFink (Post 1658652)
You did not get a definite answer form Dart because there is no definite answer. If your solid roller lifters are not restricted, use restrictors because the non restricted solid lifters will likely flood the valve train with oil at high RPM and starve the rod and main bearings.

Restricted push rods are available with .050" oil holes for engines with hydraulic lifters. I have used Comp Cams 5/16", .080" wall, chromemoly restricted push rods with full roller rockers and solid flat tappet lifters with good results. That was because the Chevrolet edge orifice solid flat tappet lifters are discontinued and aftermarket versions are difficult to find.

You could use restricted push rods with some hydraulic lifters, if necessary. Of course, you know that you must have full roller rocker arms with any kind of oiling restriction. If the valve springs run dry at high RPM, they will have elevated heating, and a shorter life, especially if they are dual springs with a flat damper. Back in my high school daze, I pushed pipe cleaners in the push rods with the old Duntov cams with single valve spring and stock rocker arms. I burned up a few rocker balls until the slotted rocker balls were introduced. The engine quit blowing oil out the valve cover breathers. In 1965, Chevrolet came out with edge orifice solid lifters in the Corvette fuel injection engines with a 30-30 camshaft.

IMO, since you have solid roller lifters and if they tend to flood the valve covers with oil, you need some sort of oil restriction and using restricted push rods is a simple and least expensive solution to the problem, without starving the rollers. Contact Smith Brothers in Bend Oregon for custom push rods. ( Smith Bros. Push Rods Bend Oregon )

Again to the OP look at your lifters the oil hole is on the side of the lifter Not in the oil band and the oil to the top end works off from bore clearance which is all ready restricted.


Go to callies website and look at the lifters and you will see they are already restricted.

http://johncalliesinc.com/product.php?ProductNo=4604

Since the OP is running a dry sump how is he going to starve the bearings??

From what I have seen with morel lifter they don't seem to flow a bounch of oil to the rockers because they are already restricted.

I have sold over between the SHP and SHP PRO blocks I have sold probably 200 plus and so far iin circle track and street and strip engines I have not seen or heard of any such issues with starving the bearings because there were no restrictors in the blocks.

I build alot of circle track engines for many years now with no restrictors and no problems.

Look how much oil goes to the top end with a hyd flat tappet cam which is a lot of oil and a solid rolller does not even come close with no restrictors !!!

I would have to call BS on flooding the valve train.

GM did the piddle lifters back in the 60's early 70's

MouseFink 03-21-2013 06:53 AM

You say the Morel and Callies lifters are restricted yet you say your circle track have no restrictors.

See what I mean:

Again, no definite answer.

I know how much valve covers are flooded with oil when using solid lifters because back in the early 1960's before GM introduced edge orifice solid lifters in 1965, when I adjusted the valve lash on my '56 Chevy e/w with the old Duntov cam, the oil pump would squirt oil over the fenders at a 600 RPM idle. In 1965, the edge orifice lifters that was used in the fuel injected Corvettes stopped that problem but then the rocker balls started failing, especially with high load valve springs...then to preven burned up rocker pivot balls, Harland Sharp introduced full roller rocker arms.

History 101:
GM introduced the hydraulic lifters with "piddle valve" in 1965 and by 1968, all GM hydraulic lifters were equipped with piddle valves. . The lifter with piddle valves were lifters GM called "high-ball" lifters because they had a secondary spring under the check ball valve that pushed the ball tighter against the plunger hole. The aftermarket called those lifters "anti-pump up" lifters.

There is "usually" no problem with flooding the valve covers with standard travel hydraulic lifters because they are restricted by the plunger and internal valving. The reduced travel, limited travel or short travel hydraulic lifters like I prefer, require restricted push rods because they will pump oil to the valve covers at high RPM just like solid lifters. They have no piddle valve to prevent lifter pump up and valve float because those type lifters have nowhere to pump up to. That is because the lifter pre-load with limited travel, short travel, reduced travel hydraulic lifters is .001" to .005".

If you want to know if your engine will have a problem with excessive oil pumping to the valve covers and reduced pressure in the crank with solid lifters, it is easy to find out by spinning the engine up to 5 grand with one valve cover off. !! Or you can just set the valve lash with the engine running and see if you will take a bath in oil. .

snakebit68 03-21-2013 07:21 AM

oil
 
OUCH!!! MouseFink...I just took an oil bath setting my solid lifters. Thanks for that reminder! Wife came out and saw the mess on the garage floor, fender wells and me...did not go well! Theres got to be an easier way...lol. I share this because I know how much oil can end up in a valve cover...( if they are on )

hcompton 03-21-2013 08:06 AM

Quote:

Originally Posted by S10 Racer (Post 1658611)
Ok guys, I have my short block together with my brand new Dart SHP block, it's going really well. One question I have is I will e running a cam driven dry sump oil system with this motor and would like know what your input is on running oil restrictors. I talked to Dart and really could not get a definate answer. The cam is a roller with Lunati roller lifters. Dart says that the SHP block is not machined for restrictors and they don't offer them but All Star Performance has designed them for this block and if running a stock oil pump, not to use them, running a dry sump or HV pump "may need to use them but not always". That's a broad answer and I would like to have a better one. The SHP has priority main oiling, what are your takes on it?

Thanks


Well most oil pumps can produce more oil than the engine can use. With dry sump and the pump at max you will need restrictors. If your using normal oil pressure levels with more volume you should be ok as the engine is already setup for normal operation with normal pumps.

Dart does not setup the blocks for it because its not always the best solution to run over 100 psi of oil pressure. If your bottom end will need the extra oil pressure to live then you will need the restrictors so you can max up the pressure to keep the bearings floating under a much higher load than stock engine will see.

I do not disagree with what has already been said just wanted to mention Dart may have a number of oil pressure psi that restrictors will be needed. Usally 100 psi and above you will surely need to limit the top end oiling and other places. If the block is not machined for them and they dont think they should be used then they have another solution to the problem. Usally they havet the oil passages redesigned so its not the concern it would be with a stock block. Either you can run high pressure without issue or the block flows more oil and does not need excessive pressure for most application.


All times are GMT -6. The time now is 01:43 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.