We do not have the information and tips arranged in any particular order, so you will have to search. The Charts for Bearing Clearances and for Torque Specifications are at the bottom of this page
ADJUSTABLE PUSH RODS
Adjustable pushrods help in many ways. Basically, they allow the proper setting of lifter preload (distance lifter plunger is pushed down when lifter is on base circle of cam). This is especially important if the block and/or heads have been milled significantly – say .025" or more total. We recommend a lifter preload of .030". Adjustable pushrods may be used even if the heads and/or block have not been milled.
ROLLER ROCKER ASSEMBLIES
Rocker Arms p26.JPG (131472 bytes)
Are they worth it? A question often asked! For most street application, no. For most strip/street applications --- maybe! Certainly such cams as the SP 235 do not really require Roller Rockers since the lift on these cams is such that stock rocker arms hold up quite nicely.
As a rule of thumb, with a lift of over .510" (using 1.55 rocker ratio), we recommend a good roller rocker assembly.
However, Roller rockers do give a greater efficiency with less resistance, more lift through a higher rocker arm ratio and just plain more dependability. You might find them to be like an investment - that is they would be a "one-time" purchase, since breakage would be nil.
They become a necessity with cams of .510" lift or more, however, since greater lifts tend to place more stress on the stock rocker arms, thus vastly decreasing the dependability factor.
There are 3 styles of Stock Rocker Assemblies:
Rocker Arm Assemblies p27.JPG (153400 bytes)Bottom: Used on '67-69 400 & 430, and 350.
Can be used on 455's using the 455 oiling system. Have 1.60 rocker ratio whereas others have 1.55 ratio. This style arm cannot be used on '70 later shafts.
Middle: Used on '70 and some '71 455's and 350's. Sometimes referred to as 'bathtub" style. Generally not as durable as the others. These arms came in Rights and Lefts
Top: Used on '71 up 455 and 350. '70 and up rocker assemblies can be used on 400, 430 and pre '70 350 heads as long as the engine is using the 455 and '70 or later oiling procedure. (Generally referred to as stamped steel. This is the style we sell. We have the 400, 430 style arms and the 'bathtub" style '70 arms available. Same pricing as the units we sell. 350 assemblies were same. Turbo V6 engines use the "stamped steel" type arms.
Proper bearing clearances have a lot to do with oil pressure. With proper clearances and a good Timing Chain Cover, a Hi-Volume oil pump is not necessary.
We recommend .002" clearance on all rod and main bearings, except for the rear main. Here we recommend .0025".
Grooved Cam Bearings: Generally, we do not recommend grooved cam bearings. The reason? When a bearing is grooved on the backside, bearing material is taken away, naturally. This somewhat weakens the bearing. Remember, the downward forces of the cam exerts most of the "wear" pressure on the bottom of the bearing. This is where the full strength of the bearing is needed.
INSTEAD of grooved cam bearings, we recommend running a small groove (at least 1/8" x 1/8") in the block, from the entrance hole on the passenger side, up around to the exit hole on the driver side. Then install the cam bearing so that no hole is at the entrance hole in the block. One of the two holes in the cam bearing should be in the 2 to 3 o'clock position so that oil will travel around the groove in the block behind the bearing and enter the cam journal area at the 2 to 3 o'clock position. This way, the oil goes directly downward, because of the rotation of the cam, to the area where it is most needed. If ever a problem occurs from wear (other than incorrectly installed cam bearings), this is the area it will show first. Good quality bearings are important. Race only bearings are not necessarily the answer as they are intended for a different use than Street and Street/Strip engines.
Adjusting Pushrods & Roller Rockers
Many of get frightened away at the thought of having to adjust pushrods. While its not exactly the most exciting thing to do, it is important. The process for adjusting push rods and roller rockers is the same.
We know from experience that .020" - .030" of preload on each lifter is desired. Very much more than this can result in the lifter plunger actually bottoming out on the bottom of the lifter. Too little preload results in plunger hitting the top retaining ring which can result in damage there. You do have some leeway with preload, but too much or not enough preload!
If your block and/or heads have been milled more than .020" combined (or you're not sure how much), then it is highly recommended you use adjustable push rods.
I'm sure you would like to know exactly how!
1) Before adjusting each pushrod, make sure its lifter is on the base circle or base of the cam lobe. This is very easy to determine if the intake is off the engine. If it isn't - then watch the movement of the valve as you rotate the crank. When the valve first begins to open, you want to stop and back off, maybe 1/4 turn of the crank. Remember, when the lifter starts rising on the lobe of the cam, it begins to push it upwards which in turn pushes up on the pushrod, rocker arm, etc. So, if you back off some, then naturally the lifter will be on the base of the lobe (or base circle).
2) Make sure the lock nut is loose.
3) Tighten the pushrod until you first feel it tighten firmly against the rocker arm. (If your intake is off, then look at the lifter [plunger, when it first starts to be push downward -- Stop).
4) At this point, turn the adjusting nut 3/4 of a turn more. This will give you approximately .030" preload on your lifter.
5) Tighten the lock nut against the adjusting nut.
6) Repeat process with nest push rod.
7) Time Saving Shortcut - For any given lifter which is resting on the base of the lobe, there will be more. Hence, you can actually do several before having to turn the engine.
In step 4 above, we mentioned that 3/4 turn represented approximately .030" preload on the lifter. This is usually the case. We say usually, simply because if the slop or slant of the threads of your pushrods are different, then 3/4 turn may be more or less than .030" preload. We have not seen any pushrods like this, but you should be aware of this remote possibility. The pushrods we sell and those on the market as far as we know are all the same thread.
Adjusting Roller Rockers -- Follow the same procedure.
TO STEEL OR NOT TO STEEL!
455 HEAD GASKETS
Composite VS Steel
We often get the question, which seals best - composition or steel head gaskets. Our experience has been that both seal equally well with street engines. We feel the block and head (sealing surfaces) preparation play an important part in sealing. This becomes more critical naturally, with higher compression engines.
One of the advantages of the steel shim head gaskets is that of extra compression, approximately .25 gain. For example, if you now have a true 10:1 compression, then with the steel head gaskets, you would have 10.25:1. This is an inexpensive way to pick up compression, however, if you are rebuilding , then consider milling the heads and/or block a little extra and use the Fel Pro composition gaskets since they are considerably less expensive.
If you've been having sealing problems, then we recommend using Fel Pro "Blue" composition head gaskets or the new "Orange" head gaskets TA Performance has available. Both are really good. If you're wanting that extra compression from the steel head gaskets, then your next alternative is to check the "trueness" of the heads.
GASKET THICKNESS COMPARISONS
on sealing ridges on sealing ridges
455 Steel .048 - .052" .020 - .022"
455 Fel Pro .050" .038"
350 Fel Pro .052" .039"
SOFT INTAKE GASKETS
Soft composition intake gaskets can help sealing the intake to your heads, especially where you may have misalignment problems due to heads being milled. These will help solve your problem where the steel intake gaskets may not.
These are available in various sizes: Standard thickness is .062". Also available in .032" and .015" for 400-455. Contact TA Performance.
To the left, top, you will see how the steel valley pan has been trimmed to fit in the valley between the heads. This will help keep the hot oil off the intake. The steel section you see is "wedged" under the lower lip of the head on each head. The soft intake gasket is then positioned appropriately (bottom left).
.030" Over Blocks are Reusable!
Sometimes a .030" block will have minimal wear and can be reused with the same or new pistons with minor re-honing.
If the above is not possible, then consider using Lightweight Pistons with .038" overbore. This way you can use Chrysler Rings, RNG455PM .043 (our Part #)
All Buick pistons, rather they be cast, forged or hypereutectic, use the 5/64" rings. 1/16" rings are usually used with special made aftermarket pistons. They are mainly intended for race applications where every effort is being made to minimize friction. Generally, 1/16" rings are not recommended for street applications.
Timing Chain Alignment/Cam Timing Tip:
On any timing set, double roller or otherwise, just because you install the timing set with the dots lined up, does not mean the cam timing will be correct. It IS possible the dots may not be located correctly on the timing gears. If they aren't, then cam timing will be off. The only way to really know is to degree everything with a Degree Kit. Yes it's extra work, but that is the only way to really know!
Oil Pump Booster Plate – Get One!
We highly recommend the use of the booster plate. It helps pressure and oil volume while at the same time no placing excessive pressure on the distributor gear. It is not a hi-volume pump. Basically, it helps improve the oil flow patterns within the pump which in itself helps increase the flow and pressure.
We really do not recommend using Hi-Volume oil pumps, UNLESS adequate pressure just cannot be obtained otherwise. Hi-Volume pumps exert unnecessary pressure on both the distributor gear and cam gear. This pressure can "wipe out" a cam in as little as a few hundred miles. Use the Hi-Volume pump only as a "patch" when nothing else can be done and rebuilding the engine is not feasible. With proper bearing clearances, you should not need anything more than a Booster Plate.
Fuel Pump Arm VS Double Roller Timing Chain
With the installation of a Double Roller, it is highly advisable to watch for contact of the fuel pump arm with the chain. This can cause drastic problems quickly.
We recommend this safe procedure. Elongate the mounting holes in the Fuel Pump. Elongate them 1/8" inch on the right side of each hole (holding the pump facing you). This will allow you to install the pump 1/8" further away from the chain. Don't go any further than 1/8" as this will place the position of the pump arm on the cam lobe, too far outward, causing it to ride too far off the edge of the cam lobe which can present problems later on.
400-455 WATER PUMP SELECTION
With the 400-455, keep in mind the year of the pulleys being used, since many of us often change pulleys. If in doubt – the short shaft pumps were generally used with the 400, 430, and '70 455's. Otherwise, most likely the long shaft pumps will be used. The short shaft pump measures 2" from the gasket mounting surface to the front end of the pump housing (not the end of the shaft). The long shaft pump measures 3" between these points.
We also highly recommend NOT using a rebuilt pump. You will be ahead of the game spending a little extra money to get a new one. We have been using and selling TRW pumps. Most local parts places can get them if they have direct access to Federal Mogul. Check around for best price as some parts houses do not have direct access and will have to charge more. Short Shaft TRW Part # is FP1400 and Long Shaft TRW Part # is FP1457.
Torque Tech Recommended Bearing Clearances:
The following recommendations are given in the Buick Manual. Our recommendations for Street/Strip Competition rebuilds are given under those. All-out race applications may or may not be the same.
400-455 350 Connecting Rod Side Clearance .0005-.0012" .0006-.0014"
Street/Strip Competition Buildup w/Steel Rods
.0012-.0030" .0012-.0030" Connecting Rod Bearing Clearance .0005-.0012" .0006-.0014"
Street/Strip Competition Buildup
Crankshaft End Play @ Thrust Bearing
Street/Strip Competition Buildup
.0005-.00075" .0005-.00075" Main Bearing Clearance .0007-.0018" .0004-.0015"
Street/Strip Competition Buildup
.0018-.0022" .0018-.0022" Rear Main .0025" .0025"
Cam Bearing Clearance in #1 Bearing
In remaining Cam Bearings
.0005-.0035" .0005-.0035" Intake Valve Clearance in Guide .0015-.0025" .0015-.0025"
Street/Strip Competition Buildup
.001-.0015" .001-.0015" Exhaust Valve Clearance in Guide .0015-.0032" .0015-.0032"
Street/Strip Competition Buildup
Piston to Cylinder Wall Street/Strip Competition Buildup w/Forged Pistons
.002" - .003" .002" - .003"
Street/Strip Competition Buildup w/Alum. Lt. Wts.
See Mfg. Recommendation
Street/Strip Competition Buildup w/Fed. Mogul
.0015" - .0020" .0015" - .0020" Piston to Valve clearance (Intake) All Street/Strip .0080" Piston to Valve clearance (Exhaust) All Street/Strip .0080" - .0100" Hydraulic Lifter Preload All Street/Strip .0030" Valve Spring to Valve Stem Guide All Street/Strip .0060" Cam to Timing Cover All Street/Strip .0002" - .0004"
Torque Tech Recommended Torque Specs
400-455 350 Spark Plugs 15 15 Crankshaft Bearing Caps to Cyl Block 110 100 Connecting Rods 45 40 Cyl Head to Cyl Block 100 80 Harmonic Balancer to Crank 200 120 Fan Driving Pulley to Harmonic Bal 23 23 Flywheel to Crank (Auto. & Man.) 58 60 Fuel Pump Eccentric to Cam (350) 50 Oil Pan to Cyl Block 14 14 Oil Pan Drain Plug 30 30 Oil Pump Cover to Timing Chain Cover 10 10
Oil Pump Press Regulator Retainer 35 35
Oil Screen Housing (Pickup tube) to Cyl Block 8 8 Oil Pan Baffle to Cyl Block 13 11 Oil Gallery Plugs 25 25 Oil Pressure Switch to Cyl Block 23 23 Filter Assem to Pump Cover 20 20 Timing Chain Cover to Block 29 29 Timing Chain Sprocket to Cam 25 25 Water Pump Cover to Timing Cover 7 7 Fan Driven Pulley 20 20 Thermostat housing to Intake Manifold 20 20 Automatic Choke Cover to Intk manifold 8 8 Intake manifold to Cyl Head 55 55 Intake Manifold (Aluminum) to Cyl Head 35 35 Exhaust Manifold to Cyl Head 20 20 Headers to Cyl Head 35 35 Carburetor to Intake Manifold 13 13 Fuel Pump to Cyl Block 20 20 Motor Mount to Cyl Block 60 60 Timing Chain Sprocket to Cam 22 22 Rocker Arm Cover to Cyl Head 4 4 Rocker Arm Shaft to Cyl Head 30 30 Delcotron Bracket to Cyl Head 35 35 Delcotron Adjusting Bracket to Cyl Head 22 22
Delcotron Mounting Bracket Thru Delcotron
to Cylinder Head at Pivot Location 20 20 Starting Motor to Block 35 35 Starting Motor Brace to Block 11 11 Starting Motor Brace to Starting Motor 11 11 Distributor Hold-down Clamp 13 13 Automatic Lower Flywheel Housing Plate 5 5 Flywheel Housing to Cylinder Block 35 35
400-455 COMBUSTION CHAMBERS by Gary Bohannon
Heads have small combustion chambers for the best compression of Buick big block heads. Install Stage 1 valves only if 455 block is used due to valve shrouding by smaller cylinders (61cc).
Heads have good compression (65cc, 3.95 cu. In.) Several have told me '70 and '71 heads were the same. I have seen numerous sets and they are different. The '70 combustion chamber protrudes out around and between the valves. Look close and you'll see ('67-'69, also).
Heads have slightly less compression than all the older heads. The combustion chamber is receded beyond the 30 degree area of the seat leaving a partial lip around each seat. (71cc, 4.33 cu. in.).
Heads have open chambers (round) and very low compression (78cc, 4.73 cu. in.).
If 400-430 heads are to be installed on a 455 block, be sure to plug the oil passage located beside the upper front head bolt hole on the dip stick side of the block. If left open, serious oil leakage will result when 455 rocker shafts are used. Bet to plug with 1/8" pipe plug (female inverted hex head) or simply pound some lead into the hole.
Before purchasing any "junk yard" heads, consider that many engines in junk yards have been overheated. Agree on a guarantee and have them checked immediately for cracks.
Which Heads on Which Blocks!
Earlier heads will fit on later blocks. Never go the other way of using later heads on earlier blocks. You will usually always have a water jacket leak as water passageways do not line up.
1/8 Mile ET to ¼ Mile ET Conversion Hint!
Here is a formula which works fairly well. It ain’t perfect, but good for comparison.
¼ Mile ET = 1/8 Mile ET X 1.56
1/8 Mile ET = ¼ Mile ET divided by 1.56
Question? or Request our Catalog
Request a Catalog
(Please give vehicle, engine and year & any other pertinent info so we can answer your question and send the correct information
Be sure to specify that you have a Buick & which engine you have.