Building a L98 Any tips?
Thread Starter
Junior Member
Joined: Apr 2000
Posts: 25
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From: Waco, Texas
Building a L98 Any tips?
I got my parts in to put my motor back together. I am going with the L98 Corvette heads on my motor. It is .30 over, etc. I have the good bearing and Melling High volume pump. I was curious if anyone had any tips that would benefit me on the assembly of the motor. Any horsepower secrets? I am going to port the heads later on so I am leaving them alone for now. Any input would really be appreciated. Thanks, BranT
TGO Supporter
Joined: Aug 1999
Posts: 14,811
Likes: 1
From: Jackson County
deburr everything, but it won't gain you any HP. get rid of the oil pump and buy a M55 and use a #26 spring from Mr. Gasket weld a brace on the pick up tube and bolt it to the pump. use a screen kit, arp rod bolts
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ICON Motorsports
1st & 3rd
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ICON Motorsports
1st & 3rd
Senior Member
Joined: Jan 2001
Posts: 527
Likes: 0
From: outerspace(maybe..pluto)?
yeah be sure to have the whole rotating assmbely balanced! it help alot! also put a good high power ignition tinto the car. check all clearances twice! dont advance or re-tard any aftermarket comp or crane cam and maybe get a hyraulic roller cam! and if you have tpi ugrade the tpi stuff!(especally the base!) use matching parts dont use wierd rpm ranges with each other!
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1989 firebird formula
Mods: converted from T.B.I. to a carburator 305 to a 350. Flowmater exhaust,hedman shortie hedders,202 heads,350 horse cam,bored.40 over, Edlebrock torker2 and a 600 edlebrock manual choke.
Future mods performer rpm air gap intake (polished) comp roller cam, and way better headsa 400 defintely in the works!
------------------
1989 firebird formula
Mods: converted from T.B.I. to a carburator 305 to a 350. Flowmater exhaust,hedman shortie hedders,202 heads,350 horse cam,bored.40 over, Edlebrock torker2 and a 600 edlebrock manual choke.
Future mods performer rpm air gap intake (polished) comp roller cam, and way better headsa 400 defintely in the works!
Moderator
Joined: Jan 2000
Posts: 19,655
Likes: 309
Bran,
In addition to the valuable advice you've already had, I've got a few other general pointers.
A few changes below:
If I think of any others, I'll edit the post.
------------------
Later,
Vader
------------------
"I'm gonna talk about some freaky sheet now..."
Adobe Acrobat Reader 4.0
KaleCo Auto Parts
[This message has been edited by Vader (edited January 28, 2001).]
In addition to the valuable advice you've already had, I've got a few other general pointers.
A few changes below:
If I think of any others, I'll edit the post.
------------------
Later,
Vader
------------------
"I'm gonna talk about some freaky sheet now..."
Adobe Acrobat Reader 4.0
KaleCo Auto Parts
[This message has been edited by Vader (edited January 28, 2001).]
Moderator
Joined: Jan 2000
Posts: 19,655
Likes: 309
Bran,
Prepare the case
Strip the engine case bare, removing all core and galley plugs, bolts, sensors, etc. Clean the inside of the case casting with a solvent that will remove the sludge. Magnaflux, dye test, or ultrasonically test the case to check for stress cracks, especially in the web areas of the crank journals. Stress relieve the case and shot pein if desired.
Machining
Align bore / hone the main bearing bores to insure the crank shaft main journals are on the same centerline. This reduces internal friction, stress, bearing wear and improves oil pressure. Check the block deck height and deck straightness. Bore the cylinders as needed or desired, then hone to a break-in finish. Insist on the use of a torque plate when boring the cylinders. The block should then be deburred. Run a bottoming tap in all threaded holes. Install 3/4" tall standpipes in the rear oil drainback holes in the lifter valley area. This will keep a small reservoir of oil at the lifters and cam bearings at the rear of the engine and allow a little better cooling of the camshaft area.
Chamfer the oil holes at the rear main cap and rear main bearing bore of the case. If you have some aircraft drills or gun drills, clean out the lifter oil galleries, crank oil passages, and passages from the cam bearings to the mains. If you accidently happen to slightly enlarge the passages, you'll get a little more oil flow. Lightly polish the lifter bores with a fine flap wheel to assure smooth lifter movement and oil holding in the bores. Take some time to polish the sealing surfaces where all the pans and gaskets will seal. A medium or fine India stone or well oiled Burr-Buster does this very well.
Cleaning
The block should then be washed with hot soapy water and bottle brushes, rifle cleaning brushes, and whatever else is necessary to clean all galleries, holes, recesses, and cooling jackets. Clean out all oil galleries with rifle brushes to remove loosened carbon and metal from drilling - don't forget the oil pressure port near the distributor. Wash the case in very hot water after all prep work. If you're lucky, you can find someone with an ultrasonic cleaning tank large enough for your case.
Apply a light coating of rust preventive after washing and air drying. Reinstall and seal the oil gallery plugs at the ends of the case. Replace all core plugs (freeze plugs) and install stainless or brass replacements with sealer. Paint the inside of the block with one coat of thinned rust-preventive enamel to seal and impregnate the casting (DON'T paint the crank or rods). Finish with a second coat of your favorite color paint at normal consistency.
Assembly
While the paint is allowed to dry thoroughly, there are a few things you can do. Soak hydraulic lifters in clean engine oil at least overnight before installation. You can soak the new timing chain in the same bath, and soaking longer won't cause any harm.
NOTE: Use assembly lube (2-cycle oil) on all parts from this point forward.
Grind, chamfer, and polish the crankshaft and balance it if necessary. Clean after machining as you would for the cylinder case, using brushes in holes and oil passages. Wash thoroughly and use compressed air to dry and blow out passages. Apply a light rust preventive.
Inspect the connecting rods and balance as necessary. Fit the wrist pins to the pistons, and have the assembly weighed and checked for dynamic balance.
Check each bore with a dial bore gauge, inside micrometer, telescope gauges, etc. Don't overlook the lifter bores. Mic the pistons for cylinder clearance. Check and adjust the rings in their bores for proper end gaps. Assemble the rings to the pistons, mark the proper cylinders, and set them aside.
Install a new set of camshaft bearings. If your hot-tank cleaning service boiled out the old bearings, they may have already installed a new set of cam bearings, so you can proceed.
Install the crank bearings and main bearings and test bearing clearances. Install the crankshaft and torque the main bearing caps. Test the rotation of the crank as you torque the caps to check for binding and clearances.
Install the pistons and rod assemblies in the bores. Rotate the assembly to check the rods for correct clearances, paying special attention to the camshaft lobes. Check the correct crankshaft end play. Install the oil dipstick tube if it was removed.
Pre-prime the oil pump with heavy straight oil (40W). Some people advocate using STP to prime the pump, but I feel it is a little too much stress on the pump shaft to drive the goo out of there on startup. Install the oil pump and trial fit the pickup tube in the pan. When you are satisfied with the pickup tube location, weld or braze the tube to the pump body/cover plate. You may want to install a secondary pickup brace. Install and trim the scrapers, windage tray, and oil pan to the case. Keep the pan bolts loose to allow fitting the timing cover and in case the pan has to come back off before final assembly.
Clean and buff the camshaft's distributor drive gear thoroughly. Install the camshaft and check for proper clearance. Install the timing chain and sprockets and check/set the camshaft degree position. Install the cam spacer button and cover, then snug the oil pan bolts.
Cylinder Heads
Cylinder heads are sometimes replaced during rebuilds, and there has been much more written on head modifications than standard case rebuilding procedures. If you are rebuilding your heads, follow the same general preparation steps as listed for the case. Strip, clean, test for cracks, perform all machining, clean, paint, and assemble with your favorite parts.
Once you have prepared or new heads, fit the new gaskets over the dowels and double check the coolant passage holes for alignment on both the case and the heads. Install and torque to the block. Install the pre-oiled lifters and check clearances. Install the push rods, rockers, and nuts. Preadjust the valves for proper lifter preload.
Final Testing
Install an new oil filter and a few quarts of fresh engine oil. Operate the oil pump with a pump shaft adapter and electric drill to test for internal oil leakage - the ability to hold pressure without leaking out internally. Test oil pressure and volume running at 500 RPM pump speed - about the maximum of a heavy-duty ½" electric drill.
Test each cylinder for compression leakage. A leakdown tester is helpful for this. Rotate the entire crank / camshaft assembly to test for tight spots, interference, and torque required to turn the engine.
When the assembly is satisfactory, install the intake manifold, harmonic balancer, flexplate / flywheel, and distributor if the application will allow it. If the distributor must be left out for installation of the engine in the vehicle, plug the opening to prevent contamination.
Happy motoring!
------------------
Later,
Vader
------------------
"I'm gonna talk about some freaky sheet now..."
Adobe Acrobat Reader 4.0
KaleCo Auto Parts
Prepare the case
Strip the engine case bare, removing all core and galley plugs, bolts, sensors, etc. Clean the inside of the case casting with a solvent that will remove the sludge. Magnaflux, dye test, or ultrasonically test the case to check for stress cracks, especially in the web areas of the crank journals. Stress relieve the case and shot pein if desired.
Machining
Align bore / hone the main bearing bores to insure the crank shaft main journals are on the same centerline. This reduces internal friction, stress, bearing wear and improves oil pressure. Check the block deck height and deck straightness. Bore the cylinders as needed or desired, then hone to a break-in finish. Insist on the use of a torque plate when boring the cylinders. The block should then be deburred. Run a bottoming tap in all threaded holes. Install 3/4" tall standpipes in the rear oil drainback holes in the lifter valley area. This will keep a small reservoir of oil at the lifters and cam bearings at the rear of the engine and allow a little better cooling of the camshaft area.
Chamfer the oil holes at the rear main cap and rear main bearing bore of the case. If you have some aircraft drills or gun drills, clean out the lifter oil galleries, crank oil passages, and passages from the cam bearings to the mains. If you accidently happen to slightly enlarge the passages, you'll get a little more oil flow. Lightly polish the lifter bores with a fine flap wheel to assure smooth lifter movement and oil holding in the bores. Take some time to polish the sealing surfaces where all the pans and gaskets will seal. A medium or fine India stone or well oiled Burr-Buster does this very well.
Cleaning
The block should then be washed with hot soapy water and bottle brushes, rifle cleaning brushes, and whatever else is necessary to clean all galleries, holes, recesses, and cooling jackets. Clean out all oil galleries with rifle brushes to remove loosened carbon and metal from drilling - don't forget the oil pressure port near the distributor. Wash the case in very hot water after all prep work. If you're lucky, you can find someone with an ultrasonic cleaning tank large enough for your case.
Apply a light coating of rust preventive after washing and air drying. Reinstall and seal the oil gallery plugs at the ends of the case. Replace all core plugs (freeze plugs) and install stainless or brass replacements with sealer. Paint the inside of the block with one coat of thinned rust-preventive enamel to seal and impregnate the casting (DON'T paint the crank or rods). Finish with a second coat of your favorite color paint at normal consistency.
Assembly
While the paint is allowed to dry thoroughly, there are a few things you can do. Soak hydraulic lifters in clean engine oil at least overnight before installation. You can soak the new timing chain in the same bath, and soaking longer won't cause any harm.
NOTE: Use assembly lube (2-cycle oil) on all parts from this point forward.
Grind, chamfer, and polish the crankshaft and balance it if necessary. Clean after machining as you would for the cylinder case, using brushes in holes and oil passages. Wash thoroughly and use compressed air to dry and blow out passages. Apply a light rust preventive.
Inspect the connecting rods and balance as necessary. Fit the wrist pins to the pistons, and have the assembly weighed and checked for dynamic balance.
Check each bore with a dial bore gauge, inside micrometer, telescope gauges, etc. Don't overlook the lifter bores. Mic the pistons for cylinder clearance. Check and adjust the rings in their bores for proper end gaps. Assemble the rings to the pistons, mark the proper cylinders, and set them aside.
Install a new set of camshaft bearings. If your hot-tank cleaning service boiled out the old bearings, they may have already installed a new set of cam bearings, so you can proceed.
Install the crank bearings and main bearings and test bearing clearances. Install the crankshaft and torque the main bearing caps. Test the rotation of the crank as you torque the caps to check for binding and clearances.
Install the pistons and rod assemblies in the bores. Rotate the assembly to check the rods for correct clearances, paying special attention to the camshaft lobes. Check the correct crankshaft end play. Install the oil dipstick tube if it was removed.
Pre-prime the oil pump with heavy straight oil (40W). Some people advocate using STP to prime the pump, but I feel it is a little too much stress on the pump shaft to drive the goo out of there on startup. Install the oil pump and trial fit the pickup tube in the pan. When you are satisfied with the pickup tube location, weld or braze the tube to the pump body/cover plate. You may want to install a secondary pickup brace. Install and trim the scrapers, windage tray, and oil pan to the case. Keep the pan bolts loose to allow fitting the timing cover and in case the pan has to come back off before final assembly.
Clean and buff the camshaft's distributor drive gear thoroughly. Install the camshaft and check for proper clearance. Install the timing chain and sprockets and check/set the camshaft degree position. Install the cam spacer button and cover, then snug the oil pan bolts.
Cylinder Heads
Cylinder heads are sometimes replaced during rebuilds, and there has been much more written on head modifications than standard case rebuilding procedures. If you are rebuilding your heads, follow the same general preparation steps as listed for the case. Strip, clean, test for cracks, perform all machining, clean, paint, and assemble with your favorite parts.
Once you have prepared or new heads, fit the new gaskets over the dowels and double check the coolant passage holes for alignment on both the case and the heads. Install and torque to the block. Install the pre-oiled lifters and check clearances. Install the push rods, rockers, and nuts. Preadjust the valves for proper lifter preload.
Final Testing
Install an new oil filter and a few quarts of fresh engine oil. Operate the oil pump with a pump shaft adapter and electric drill to test for internal oil leakage - the ability to hold pressure without leaking out internally. Test oil pressure and volume running at 500 RPM pump speed - about the maximum of a heavy-duty ½" electric drill.
Test each cylinder for compression leakage. A leakdown tester is helpful for this. Rotate the entire crank / camshaft assembly to test for tight spots, interference, and torque required to turn the engine.
When the assembly is satisfactory, install the intake manifold, harmonic balancer, flexplate / flywheel, and distributor if the application will allow it. If the distributor must be left out for installation of the engine in the vehicle, plug the opening to prevent contamination.
Happy motoring!
------------------
Later,
Vader
------------------
"I'm gonna talk about some freaky sheet now..."
Adobe Acrobat Reader 4.0
KaleCo Auto Parts
Member
Joined: Jul 1999
Posts: 496
Likes: 0
From: Chicago, IL
Car: 89 IROC-Z
Engine: LB9
Transmission: 700-R4
Always do a "pre-assembly" or two to check all clearances before you do it for real. Make sure everything is kosher. I'm not sure if you already have all the parts you're going to use, but usually aluminum parts are a waste of money unless it's a hardcore racing engine. If you haven't gotten rods or pistons yet, use the longest rods possible for max hp/tq. I've been researching airflow and there are some new pistons (most likely ungodly expensive though) that are machined in such a way that they "swirl" combustion exhaust up toward the exh port on the head and this results in approximately 8% more efficient combustion! Just a thought. Why not do the heads now? There's never an easier time. Also try to fit the top piston ring as high up as possible for better sealing and life. I have other tips, but I've never built an engine (will soon) but I just research things a lot. Get a copy of smokey yunicks "power secrets" for sure if you don't already have one - he's amazing.
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Base: 89 Iroc-Z LB9 auto 2.73 posi
Exh: 3" Dynomax muffler, 3" Pipe in place of cat
Ign: Accel 300+ wires, cap&rotor
Fuel: Cleaned and flow-matched injectors, afpr, !air pump&diverter valve
Sound: Clarion deck, Kicker speakers and amps
Suspension: KYB Shocks, BMR Strut Tower Brace
Misc: TB Bypass, Synthetic Oil, Flexlite Transmission cooler,
free mods, hopefully engine swap and 4th gen seats in the works...
------------------
Base: 89 Iroc-Z LB9 auto 2.73 posi
Exh: 3" Dynomax muffler, 3" Pipe in place of cat
Ign: Accel 300+ wires, cap&rotor
Fuel: Cleaned and flow-matched injectors, afpr, !air pump&diverter valve
Sound: Clarion deck, Kicker speakers and amps
Suspension: KYB Shocks, BMR Strut Tower Brace
Misc: TB Bypass, Synthetic Oil, Flexlite Transmission cooler,
free mods, hopefully engine swap and 4th gen seats in the works...
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