Question about 2004 Pontiac GTO

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What is engine blueprinting?what is needed to bring out more power to the engine? For example, could mere balancing of like let's a pulley add some power to the engine? Thanks.

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Blueprinting is a very exhaustive and extensive process of rebuilding the engine. When the engine is designed, there are specifications for every dimension of every engine part. Since the parts are mass-produced, there is no way that they can be made exactly to spec, so there's a tolerance allowed on the parts (for example, the weight of a piston would be specified as X number of ounces, plus or minus 10%). Same for connecting rods, wrist pins, the inside diameter of each runner in the manifolds, weights and dimensions of valves, etc.

When an engine shop blueprints an engine, it means they build it to the exact specification for each part and clearance in the engine. They may order 50 pistons for a V6 engine, and will measure all of them for all size and weight dimensions, and won't stop until they get six that match exactly. They'll then do the same for the six rods, six wristpins, the valves, crankshaft, etc. They'll take the intake manifold and will usually bore it out (or extrude-hone it, which involves flowing a high-temperature, abrasive clay through it at high speed/pressure to polish and enlarge the volume for better airflow). Ditto that for the exhaust manifolds. They'll do a full hot-tank treatment on the block, metallax the block (alternate heating and cooling of the block to make the crystalline structure of the engine block metal more regular, and thus stronger), cross-hatch the cylinders for oil retention on the walls (better lubrication and less friction as the pistons move), order cams with an optimum grind for valve lift and duration (this determines the airflow characteristics of the engine, where it'll make peak power and torque, etc), they'll knife-edge, balance, micropolish, and shotpeen the crank for less turbulence in the oil pan and lighter rotating weight (so it doesn't drain as much power), and they'll assemble it all to exacting fit and torque specs.

The end result is that you can gain 20% or more output from the engine, or even more still if they do porting/polishing on the components, extrude-honing, etc. With that stuff and custom-spec cams, the output could go up 30-40% even. It's a big power gain, but it comes at a big cost (as I'm sure you can tell). It's only really worth it on a race engine. Anyone who says they can blueprint a motor for a grand or less is full of it. You'd honestly be looking at $2000 or more easily if you only rebuilt it to stock spec with stock parts. Using aftermarket, high-performance parts, custom cams, extrude-honing, porting and polishing, etc, can easily kick the price up to $5000 at the least, and depending on the components you buy, $10-20,000 is very easy to ring up. It's not for the faint of heart. But it may be all the difference in racing, especially in an SCCA class like Spec-Miata racing, where engines have to be unmodified (as in, using only OEM parts). There's no rule against blueprinting as long as the parts are all available at the dealership parts counter. It says you have to use stock parts, but it doesn't forbid you from using the best possible combination of stock parts possible.

Posted on Nov 17, 2009

Testimonial: "That was indeed very informative. Thank you j_del and I appreciate your time to touch impt. points in the process of blu-printing."

  • Veron1 Oct 11, 2010

    " Whoa! Way to go bro.. Lots of info that I hadnt known about.Thanks a ton.. -Veron


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When engines are built at the factory there is a fairly wide range of tolerances allowed, when u blue print the engine you fine tune the engine to the exact spes set up by the engineer who designed it, u make all the combustion chambers exactly the same volume, all the valves cut just right and the same depth in the head, u fine tune the valve timing to exactly the right spec and so on for the rest of the engine, also u make sure everything is balanced perfectly.

Posted on Nov 17, 2009

Testimonial: "Thank you emissionwiz for the info. I believe you have give me a rounded idea what engine blu-printing is."


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Rotax 503 i do not trust anymore scarry stuff!when it stops close to ground

Be good if you asked your question...

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Most of the disadvantages can be reduced by careful building to very fine tolerances, what is know as "blueprinted". That goes some way to explain why those engines approved for use in aircraft cost more than double of those used on the ground.

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99 trooper 3.5 v6 , believe balancer pulley sheared the key.pulley is wobbling and motor knocking like rod this a zero tolerance engine and are they known for this problem.sounds like motor is out...

IT is a zero tolerance engine which means that if you break a timing belt there will be valve damage. Check the harmonic balancer and if there is a rubber insert between the pulley and the crank shaft hub then replace the harmonic balancer as this rubber has failed and the pulley will fall off. If the key has sheared as you suspect there would be no engine noise as the engine would not be running. Fix the balancer first then check for the noise as it may be just the balancer

Sep 08, 2013 | 1999 Isuzu Trooper

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2001 dodge stratus r/t 3.o liter outside pulley on harmonic balancer fell off. do i need whole new balancer or is there something that came off that holds it on?

ON most engines there is only on pulley as part of the harmonic balancer. It is the on that has the rubber between the pulley and the center bit on the crank. Any other pulleys are normally bolted to this pulley on the center hub piece . I'm thinking that the mount bolts have fallen out.

Apr 20, 2013 | 2001 Dodge Stratus

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Ho to replace Harmonic Balancer/Crank Pulley

the pulley will be either pressed on or bolted on
if pressed on you will need a harmonic balancer puller to get it off and space to swing a hammer to put it back on
if bolted it will be torqued to up to 90ftlb so holding the crank to undo the nut is a problem so get a 1/2 " impact gun for the job
you will need space for the tools so look at what has to be removed first
next there is a crankshaft position sensor behind the pulley so be careful with wires in that area
some engines have the pulley bolted to a crank hub with 3 or 4 small bolts in which case the job gets simpler
the item to watch out for is the drive key in the crank shaft as it can fall out of place and fall inside the seal especially when refitting the balancer

Jul 14, 2017 | 1995 Pontiac Trans Sport

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I have a 1999 Chrysler Cirrus. The serpentine belt came off that goes to the alternator and the air conditioner unit, I was told by a mechanic that the dampner pulley is bad. Some autopart sites have a...

Hi, assuming you have the 2.5 liter engine, your damper is integral to the pulley assembly as shown in the second figure below, so there is only one part involved. You can see an example of the part here:
If you look carefully at the pic below, you can see the rubber torus inside the pulley. The rubber is what fails and causes the pulley to wobble. You may need to borrow a puller to get the pulley off.

2.5L Engine
  1. Before servicing the vehicle, refer to the Precautions section.
  2. Disconnect battery negative cable from remote negative terminal on shock tower and properly isolate to prevent accidental reconnection.
  3. Remove or disconnect the following:

    Belt splash shield Accessory drive belts. Refer to Belts. Crankshaft center bolt and remove crankshaft damper.


    Fig. Splash shield removal-2.5L engine


    Fig. Crank damper and bolt- 2.5L engine

To install:
  1. Clean crankshaft snout and crankshaft damper bore.
  2. Install or connect the following:

    Crankshaft damper. Crankshaft bolt and torque to 143 ft. lbs. (182 Nm) Accessory drive belts. Refer to Belts. Belt splash shield

Oct 05, 2011 | 1999 Chrysler Cirrus

2 Answers

Where is the crankshaft sensor on a 3.8L in a 97 buick lesaber

The sensor is located to the right of the crankshaft behind the vibration dampner (harmonic balancer). You will need a balancer puller and a special tool to space the new sensor correctly.
(can be done also with eye spacing, but the tool is recommended to ensure proper spacing as to prevent damage to new sensor and / or harmonic balancer.) You will also need a strap wrench to hold balancer pulley in place while removing and re-installing balancer to crankshaft bolt. (helper required)

Procedure for replacement:
Remove negative battery cable.
Set parking (emergency) brake.
Release tension on serpentine drive belt and remove belt from harmonic balancer pulley. ( large pulley at bottom of engine)
Break loose lug nuts on passenger side front tire, do not remove bolts yet.
Raise and support vehicle on passenger side, remove wheel.
Remove plastic splash guard (cover) from passenger side wheel well.
Remove dampner / balancer center retaining bolt (counterclockwise, it is torqued very tight.) Use a strap wrench around pulley and have a helper hold that in place while using a 1/2" breaker bar and socket to turn pulley bolt out of crankshaft. Be careful not to rotate engine in a counterclockwise direction while breaking the bolt loose.
Using balancer puller, remove dampner / balancer pulley from engine.
You will now see the crank sensor to the right of the crankshaft bolted to the timing cover.
Disconnect sensor wiring and remove retaining bolts, remove sensor.
Put new sensor in place and screw in bolts, do not tighten them yet.
Reconnect wiring to sensor.
Now use special tool to properly space sensor. If you cannot find one at the parts store, you can space the sensor with the balancer pully held in place (not installed yet) and space the sensor evenly with the veins on the hub of the balancer pulley. Take your time and be sure it is as evenly spaced as possible.
Tighten sensor bolts.
Clean balancer hub free of any oil and dirt deposits using brake or carbeurator cleaner.
Reinstall balancer to crankshaft by tapping around the inner surface of pulley with a rubber hammer.
It is a press fit, so be sure you have it started evenly and progress slowly in a circular motion to ensure you are keeping it aligned straight with the crankshaft.
Reinstall balancer bolt using the same method as removal, torque bolt to 110 foot pounds, then tap around balancer again twice with rubber hammer, turn the engine 2 full revolutions clockwise using the balancer to crankshaft bolt, then tighten bolt an additional 1/4 turn.
Replace splash guard, put wheel on tightening lugs to finger tight and then wrench tight in a star pattern.
Lower vehicle until wheel makes contact with floor, tighten lug nuts to 115 foot pounds in a star pattern using a torque wrench.
Fully lower vehicle, remove jack.
Re-install serpentine drive belt
Re-connect negative battery cable.

End of procedure....Hope that helps!.....Mike

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4cyl 2000 honda accord engine stalls while idling, recently died and will only start for short periods... possible problems/solutions?

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Timing Belt & Balancer Belt

Removal & Installation

2.3L Engine

To Remove:

  1. Record anti-theft code for radio.
  2. Disconnect battery negative cable then positive cable.


  3. Turn crankshaft pulley until TDC is achieved.
  4. Raise and safely support vehicle.
  5. Remove front tire assembly.
  6. Remove splash shield.
  7. Remove power steering belt.
  8. Remove alternator and alternator bracket.
  9. Safely support engine under oil pan.

    Upper bracket removal

  10. Remove stop, detach ground cable and remove upper bracket.
  11. Remove cylinder head cover.
  12. Remove upper cover.
  13. Remove dipstick and tube assembly.
  14. Remove crankshaft pulley.
  15. Remove adjusting nut rubber seal and remove lower cover.

    Timing belt/balancer belt removal

  16. Loosen adjusting nut 1 turn.
  17. Push up on balancer belt tensioner to relieve belt tension.
  18. Push down on timing belt tensioner to relieve belt tension.
  19. Tighten adjusting nut 1 turn.
  20. Remove balancer belt and timing belt.

To Install:

NOTE: Clean balancer belt drive pulley, timing belt pulleys and
upper/lower timing cover prior to belt installation.


  1. Set timing belt drive pulley to TDC by aligning dimple on pulley with dimple
    on oil pump.


  2. Set camshaft pulley to TDC so that "UP" mark is at top and grooves align
    with top of cylinder head.

    Timing belt installation

  3. Starting with driver pulley, install timing belt in a counterclockwise
  4. Loosen and ten retighten adjusting nut.
  5. Install balancer belt drive pulley.
    NOTE: Inspect rubber seal on lower cover and replace as necessary.

  6. Install lower cover.
  7. Install crankshaft pulley and bolt.
  8. Rotate crankshaft pulley counterclockwise several times to seat belt.
  9. Loosen adjusting nut 1 turn.
  10. Rotate crankshaft counterclockwise 3 teeth on camshaft pulley.
  11. Tighten adjusting nut to 33 ft lb (44 Nm).


  12. Turn crankshaft pulley until TDC is achieved.


  13. Ensure that camshaft pulley "UP" mark is at top and grooves align with top
    of cylinder head.
  14. Remove crankshaft pulley and lower cover.
  15. Rotate crankshaft to TDC again and lock timing belt adjuster arm with a 6 mm
    timing cover bolt.
  16. Loosen adjuster nut 1 turn and ensure that belt tensioner freely moves.
  17. Push tensioner up and tighten adjusting nut.

    Balancer shaft alignment

  18. Remove bolt and washer from maintenance hole.
  19. Using a 6 X 100 mm bolt, scribe a mark 2.9 in (74 mm) from end.
  20. Insert bolt into maintenance hole and hole in balancer shaft.
  21. Install bolt up to scribed line.

    Balancer shaft alignment

  22. Align groove on balancer shaft with pointer on oil pump housing.
  23. Install balancer belt and loosen adjusting nut 1 turn to tension.
  24. Retighten bolt.

    Balancer shaft alignment

  25. Remove bolt from maintenance hole and install bolt and washer. Tighten to
    22 ft lb (29 Nm).
  26. Reinstall crankshaft pulley.
  27. Loosen adjusting nut 1 turn.
  28. Rotate crankshaft pulley counterclockwise 1 turn and tighten adjusting nut.
  29. Remove bolt from timing belt adjuster arm.
    NOTE: Inspect rubber seal on lower cover and replace as necessary.

  30. Remove crankshaft pulley.
  31. Install lower cover.
  32. Install seal at adjusting nut.
    NOTE: Crankshaft pulley, bolt and washer must be cleaned prior to

  33. Lubricate crankshaft pulley bolt between head and washer and bolt threads
    with clean engine oil.


    Do not use impact wrench to perform
    following step.

  34. Install crankshaft pulley and tighten bolt using special tools to 181 ft
    lb (245 Nm)
  35. Install dipstick/tube assembly.
  36. Install upper cover. Tighten bolts to 9 ft lb (12 Nm).
  37. Install cylinder head cover.
  38. Install alternator bracket and alternator.
  39. Install power steering pump belt and alternator belt.

    Upper bracket installation

  40. Install upper bracket and tighten fasteners in proper numbered sequence.
  41. Install stop.
  42. Install battery and enter radio anti-theft code.

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Oct 29, 2010 | 2000 Honda Accord

1 Answer

Directions of how to change a power steering pump

  1. Disconnect battery ground cable.
  2. Disconnect inlet and outlet hoses from pump.
  3. Remove serpentine belt guard as necessary.
  4. Remove belt from pulley, using 1/2 inch breaker bar.
  5. Remove coolant recovery bottle as necessary.
  6. Remove pump assembly.
  7. Transfer pulley as necessary.
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    1. Turn wheels all the way to left.
    2. Add power steering to Cold mark on fluid level indicator.
    3. Start engine and run at fast idle, then add fluid, if necessary, to bring level to Cold mark.
    4. Bleed system by turning wheels from side to side without hitting stops. Keep fluid level at Cold mark.
    5. Return wheels to center position and continue running engine for 2-3 minutes.
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Aug 19, 2010 | 1992 Oldsmobile Cutlass Supreme

3 Answers

Balancer pulley turns 1/8 turn before crank

Remove yonder pulley and you will find the bolt holes are elongated. get another from a scrapyard (take the bolts too.) replace and you should be fine.

Apr 07, 2009 | 1994 Buick Regal Gran Sport

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