rsicard

Mike: Keep up the GOOD work. Learning valuable advice from reading these posts. Specifically, bolts seizing at the exhaust collector flange. I spot welded clinched self locking nuts to the upper portion of the header exhaust flange. WRONG! Need to run a tap one each of the self locking nuts to remove self locking attribute. Also need High Temp Anti Seize compound on the bolts which thread up from the bottom into the nuts on top. You guys keep the details coming as there are MANY lessons to be learned from what you post!

From the Video, it sure sounds like a (collapsed?) lifter making noise. Get a engine stethiscope and touch it to the cylinder head when running. The lifter noise should be more dominate. Take the valve cover off, run the engine again and put pressure on each rocker arm to see which one quiets down the noise. This will locate the offending lifter.

It is really NICE that someone is listening to honest advice. Most of the aftermarket crankshaft manufacturers have more of a supply of earlier crankshafts for the earlier 350 block castings. In most cases the lighter cranks are ONLY available for earlier 350 block castings. Maybe one can special order lighter cranks in the 1 piece rear main seal configuration. Scat offers Q-Light (lighter weight) connecting rods for 350 applications. SRP has professional (forged) pistons that are just the appropriate configuration for best squish/quench. They are costly but worth the value. Mate these with AirFlowResearch cylinder heads, deck the block to get maximum squish without the piston kissing the cylinder head, then lower octane fuel can be used for a faster burn. Then the engine has tolerable static compression ratio without the threat of detonation with reduced octane.

Why to you need turbo(s)? If the 383 is done properly, HP and TQ can be 500+ each. Be careful with a .060" over block. Have the cylinder walls Sonic tested for thickness. Having gone .060" over, it likely an OLD style block and core shift may be present. Read my previous POST and think about it carefully! These later style blocks usually need only .030" over bore. The REAL benefit of the later block is the DEEPER/LONGER lifter bores. Much better geometry for AGGRESSIVE camshafts. The camshaft and cylinder head specs go hand in hand. Also consider 1.6 ratio rocker arms for better more aggressive valve lift to accommodate cylinder head flow numbers. And lastly, strong springs for cylinder head and THICK wall push rods that reduce flexing.

If there are strands of conductor wire sticking out of the insulation, that is a BAD thing. Insulate the bare strands of wire with GOOD electrical tape as insulation such that bare conductor strands do not come in direct contact with anything else, especially not the metal chassis of the car.

If the 260Z engine is still running, keep it running and focus on the suspension first. Modify all four struts for adjustable coil overs. Then on to the rear differential. Do any necessary body work for rust issues. Install Bad Dog frame rails. Then tackle the engine and transmission change.

Likely the fan has three wires because it is a two speed fan. Remove both of the positive wires and connect only one at a time to see what happens to the fan. Cap and stow the unneeded fan wire.

Caution! If relays and wiring is getting hot, the wire is not large enough for the current passing through it. Relays getting hot says they are not rated for the current passing through them. Need higher current rated relays.

Investigate the Crane Cams distributor. It has a solid state vacuum and pseudo mechanical sensors that can each be individually adjusted. These two curves can be custom set.

You are doing a VERY GOOD job. Keep up the good work. At some point the body needs to be taken to a media blaster and have the surface rust taken off. Also the new steel needs to be blasted also. Then blow it all off and shoot a coat of primer needs to be shot onto the bare metal as soon after media blasting.

Jack: Strongly consider a 1996-1999 350 vortec block. The reason is that it was designed as a roller lifter block with lifter bores 0.30 inch taller than before. This is a geometry advantage when using a more aggressive lift profile on the camshaft. Compcams has a good program for selecting camshafts. Given a good bottom end block, the power producers are the cylinder heads, performance camshaft selected to take advantage of the cylinder heads and a induction system to match the cylinder heads. The cylinder heads need to have strong valve springs to accommodate the designed RPM range. The highest performance camshaft would be for SOLID ROLLER LIFTERS as the profile can provide higher (and honest) lift and steeper opening ramp to accommodate the flow numbers for the cylinder heads. Suggest SRP Pro Pistons (light weight plus thin and effective rings), 6 inch Scat I beam connecting rods and 3.75 stroke crankshaft all balanced internally. Neutral balance fluidamper and neutral balance flywheel/flexplate.

Run a clean-out tap into the cylinder head intake manifold holes to make certain they are clean. Then lube the intake manifold bolts with ant-seize and torque them from the center to the outside. They will be much easier to remove after applying the anti-seize. This process should be used extensively on the engine.

$100.00 is a reasonable price for the engine. The cylinder heads alone may be worth that much. Replace the head gasket and do a leak-down test on each cylinder. You may be surprised that it still has life if it was run with the fuel injection system that DOES NOT wash down oil in the cylinders as carbs DO. It also has a 1-piece rear crankshaft seal and 0.3 TALLER lifter bosses as it is a roller-cam engine.

Mr. Blah: In looking at the number of posts you have made, it is obvious that you need to thoroughly study all of the relevant forums here to answer your concerns. Suggest also INTENSIVELY study the JTR conversion book.

Partial list: 1) What kind of condition is the engine in? Do a leak-down test of each cylinder to determine the condition. Remove the pan, the main bearings and the rod bearings one at a time, photograph and reassemble each one immediately. If you have the micrometers, measure the mains and rods for clearances. If they are OK, then replace the oil pump when down there. That is just good INSURANCE. 2) What kind of condition is the body in? Check for rust through in the floor pans. 3) What kind of condition is the suspension in? Check the condition of the springs and shocks. 4) The T5 is likely the best transmission for the money. 5) Plan on upgrading the Front Brakes to a larger rotor and caliper. Replace both front and rear flexible brake lines as a safety measure. 6) Plan on upgrading the rear differential, half shafts and stub axles. 7) Don't be afraid of purchasing the JTR kit for the engine and trans mounts. 8) Replace all the rubber suspension bushings with poly. 9) Replace the steering rubber dampener (puck) with poly. 10) replace the front sway bar with 1" diameter bar.

There is a significant variance on the number 2 cylinder. Suspect there is may be a valve leak there. Thus the reason for the leak-down test wherein the leak can be listened for via the crankcase (rings), intake and exhaust to see which are at fault. Without adequate testing and tear-down it is difficult to make and absolute assessment. Testing EGT for each cylinder may reveal something.

Notice that "If using all forged bottom end components," was stated. Forged bottom end, crankshaft, con rods and pistons will stretch MUCH LESS than non-forged components. 0.025" or less is pushing the limit.

Concentrate on getting the top of the piston level with the top of the block or slightly above same. Get as much squish as possible between the piston and cylinder head. If using all forged bottom end components, shoot for .030 inches between the piston and cylinder head with as much area of the squish pads piston and cylinder as possible. This should greatly reduce tendency to ping. Check for adequate valve to piston clearance with piston at 10 degrees before and after TDC taking into account the total valve lift plus 0.100 inch clearance.

Is there a corresponding trace of evident hot spot on the cylinder head/valve chamber or piston? What material are the pistons composed of? Are the pistons flat top configuration? Post pictures of the combustion side of the cylinder head. Suspect there is a hot spot, on the piston or cylinder head/valve near where the gasket was burned through. With a good head gasket in place, what does a leak-down test reveal?

It is TRULY amazing how little people know about the science of ceramics. Does dumbth rule?

From what is being discussed here, it appears that ceramic and slippery coatings are not appreciated as to their value. NASCAR engine builders would NEVER build without these coatings. The ceramic coating on the top or crown of the piston DRASTICALLY slows down the migration of combustion heat though the piston. The same is true with valve faces and cylinder head combustion area if COATED with ceramic. Therefore the GREATEST amount of combustion heat is used to convert reciprocating piston motion to rotary motion of the crankshaft. More power is extracted from the combustion heat rather than being absorbed or LOST by pistons, valves and cylinder head combustion chamber. This is just GREATER EFFICIENCY of the combustion! As far as underside piston squirters, the Oil Galleries must be tapped for this additional oil. Additionally, the oil pump must provide MORE VOLUME of oil. The oil squirters should have a relatively SMALL ORFICE in order to spray the hottest portion of the underside of the piston in order to remove heat from same.

There have been Piston Oiling holes in the Generation 1 Small Block Chevrolet. They were drilled into the upper Main Bearing boss and bearing insert aimed upward at the piston. Likely the oil squirted landed on the connecting rod and cylinder wall. The only good way to get oil cooling to the bottom of the piston is to have pressurized oil up the center of the connecting rod with squirters spraying directly, and close to, the bottom of the piston. Likely there would NOT be enough pressure after the main bearings are oiled then to feed holes to the rod journals and then on up the connecting rod. This would be a LONG oiling path.

In rethinking the piston cooling, coating the piston crown with ceramic mixture and ALSO squirting oil on the bottom of the piston would FURTHER reduce the heat that migrated through the piston crown ceramic coating. Also provides more lubrication of the cylinder walls. The best of both methods. The NASCAR engine builders make exclusive use of coated engine components. They use every science that will benefit the durability and performance of engines. They want the best performance and fuel economy possible. They run their engines close to the edge of destruction.

Coating the piston is doing just HALF the job. How about valves and cylinder heads also as they take just as much heat as the pistons do?

Your post does not indicate what type of materials and thicknesses of same you want to weld. The post is confusing as to whether you have or do not have a MIG welder. If the material is lighter gauge steel used most of the time, the best is the MIG welder. Suggest getting a Miller 211 if you do not have a MIG welder. This will cover most of the welding tasks unless you are welding heavy gauge steel. Also there is a spool gun available for the Miller 211 that will allow you to weld Aluminum. Most of my steel/iron welding can be done with a Miller 211. As for learning welding, some techniques apply to both MIG and TIG welding. Specifically, leaning your hand which is holding the torch onto something solid will allow much more precise control of the torch which is especially important in TIG welding. The same is true with MIG welding also. MIG is easier than is TIG. As to learning welding MIG or TIG, recommend getting training DVD's by Ron Covell. He is a MASTER in metal working.