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THINKING OF ENGINE REBUILD SOON

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Old 12-06-2010, 12:57 PM
  #46  
Landseer
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A home DIY cobble is different than a shop-backed rebuild, right? Like about 15K different.
Old 12-06-2010, 01:02 PM
  #47  
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Originally Posted by RED SHARK 1990
I think that is a much sarcasm on your end ,if you see the car at sharktoberfest you would have been surprised by the condition. Interior is by Paul and ROBB, aswell as fact leather Porsche pieces. Interior restored close to 8grand or more. I am looking on the forum for advices with many parts replaced and wanted the car to last. Replacing the whole car then you simply buy a new car,but not a brand new 928...
Yes, I was indeed being sarcastic.

It seems you are doing work on the engine just for the sake of doing the work, with no clear direction or reason.

As they say around here - 'it's your car, do what you want', but, expect some 'guidance' when it seems you may need it.
Old 12-06-2010, 01:03 PM
  #48  
blown 87
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Originally Posted by Landseer
A home DIY cobble is different than a shop-backed rebuild, right? Like about 15K different.
In more ways than just money.
Old 12-06-2010, 02:19 PM
  #49  
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I understand doing it right (meaning taking NO chances, but there are always chances) and doing it smart and cost effectively. everyone has a threshold.
Ive built several racer 5 liter hybrids and never really did anything but change the heart of the engine, the block. in fact, i reused all gaskets that looked decent. (like intake gaskets, and valve cover cover gaskets on the S4, but not on the 2 valve versions) always new main seals, pilot bearing, rings, bearings and water pump and oil pan gasket with a new timing belt. thats it! add it up. its not much.

used short block is about $1000
rings, rod nuts, bearings seals, etc etc maybe $600
notch the pistons and have a professional install the rings , $300
OPTIONAL: balance the rotating the assembly, which is not needed if you are just notching the pistons, $800

Then go to town. its just an assembly and checking your work and clearnaces process. $2-3k and you have a brand new 5 liter.

Now, Scots was a little more, because we had to bore his block (4.7 to 5 ltier) balance the rotating assembly, as it was made from a hodge podge of parts from 4.7 cranks, to who knows where rods and off the used shelf 85 pistons. we tip/tail balanced the rods, and then balanced the rotating assembly. so,it was like building from scratch. this cost us an extra $1000 ,but we knew what we had when it was done. we could have saved money by just doing the way I suggest above, but we already had the block, rods and used 84crank, so it was a little more money to do it that way.

Well, should you rebuild/replace) the timing tensioner, oil pump, valve springs, lifters, all the intake seals???? I dont know. I have never replaced anything that didnt look and feel good and so far, 4-5 race cars later, with the most amount of race miles here on the list for a 928, i have never seen any issues. the point is, there are always unknowns, especially if you go out and change EVERTHING. who is to say that the replacement part is going to be better than new. heck, you know my water pump stories. If its working and feels like its solid, it goes back in. whats the worse that can happen, it might make noise in a year or two and Ill lhave to replace it? heck, ive had new pumps in there for 1 min that needed to be pulled. (and 1 month and 6 month, etc etc.)
anyway, I dont think anyone doubts the quality of the internals of our engines. you want an easy upgrade, just bolt on a used 85 short block to your old 4.5 or 4.7 US. 300ccs always helps!
Old 12-06-2010, 02:22 PM
  #50  
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yes, just re-ring it, re -rod bearing it and thats it.

why would you put some used 4.7 euro in a car without taking it apart. Now that is one chance we took with scots car and it BIT us hard! the next one, we took apart and build it like we are talking about. BUT, for the same cost, we could have had a 5 liter. notching the pistons is so easy, you could do it with a dremel, but use a machine shop. $300 for perfection in the valve cuts is a great bargain.

Originally Posted by Iwanna928
If someone found a 85/86 shortblock and wanted to refresh it what exactly would they do? Re ring the piston's, check the bearing's? I thought I read that the bearing's available now are inferior to the stock one's in the original motor.

In doing a hybrid, off topic, wouldn't it save cost's to do a euro 4.7L and save on machine cost's of the 5.0L block in regards to valve relief and give up .3L?

Mark K wrote about cost's on a 5.0L block being around 3,500 which he did the work himself, add a couple k and a refreshed, not rebuilt shortblock would be around 5500.

How far does one have to go to be safe with a shortblock change?
Old 12-06-2010, 03:09 PM
  #51  
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It just has a few teeth off of the cam gear, it will be fine.
Right Mark.


Originally Posted by mark kibort
I understand doing it right (meaning taking NO chances, but there are always chances) and doing it smart and cost effectively. everyone has a threshold.
Ive built several racer 5 liter hybrids and never really did anything but change the heart of the engine, the block. in fact, i reused all gaskets that looked decent. (like intake gaskets, and valve cover cover gaskets on the S4, but not on the 2 valve versions) always new main seals, pilot bearing, rings, bearings and water pump and oil pan gasket with a new timing belt. thats it! add it up. its not much.

used short block is about $1000
rings, rod nuts, bearings seals, etc etc maybe $600
notch the pistons and have a professional install the rings , $300
OPTIONAL: balance the rotating the assembly, which is not needed if you are just notching the pistons, $800

Then go to town. its just an assembly and checking your work and clearnaces process. $2-3k and you have a brand new 5 liter.

Now, Scots was a little more, because we had to bore his block (4.7 to 5 ltier) balance the rotating assembly, as it was made from a hodge podge of parts from 4.7 cranks, to who knows where rods and off the used shelf 85 pistons. we tip/tail balanced the rods, and then balanced the rotating assembly. so,it was like building from scratch. this cost us an extra $1000 ,but we knew what we had when it was done. we could have saved money by just doing the way I suggest above, but we already had the block, rods and used 84crank, so it was a little more money to do it that way.

Well, should you rebuild/replace) the timing tensioner, oil pump, valve springs, lifters, all the intake seals???? I dont know. I have never replaced anything that didnt look and feel good and so far, 4-5 race cars later, with the most amount of race miles here on the list for a 928, i have never seen any issues. the point is, there are always unknowns, especially if you go out and change EVERTHING. who is to say that the replacement part is going to be better than new. heck, you know my water pump stories. If its working and feels like its solid, it goes back in. whats the worse that can happen, it might make noise in a year or two and Ill lhave to replace it? heck, ive had new pumps in there for 1 min that needed to be pulled. (and 1 month and 6 month, etc etc.)
anyway, I dont think anyone doubts the quality of the internals of our engines. you want an easy upgrade, just bolt on a used 85 short block to your old 4.5 or 4.7 US. 300ccs always helps!
Old 12-06-2010, 04:04 PM
  #52  
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Never really heard of an S4 motor needing an overhaul at that mileage. I have almost 170,000 on mine now and after all the FI work done, it runs better than it did when I bought it with 108,000 on it.

If you are seriously considering a rebuild, I am willing to bet the only thing you really need are main & rod bearings, chain tensioner pads & chains, hone the block for a nice smooth alusil coating, and a valve job. Other than that, if it's about oil consumption, check your breather hoses and the intake boot of the throttle body.

There are supercharged cars on here that don't have as many oil blow-by complaints as this thread.

There is a place in National City that does great work on alusil lined engines. They did my 944 motor and rebuilt the head for a price that was a steal. They charge double for the 928 motor if you take it apart yourself and bring them the block. Again, very reasonable prices...only if your are absolutely serious.
Old 12-06-2010, 04:17 PM
  #53  
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As long as those teeth missing are not next to one another.

hey, the missing cam teeth were not a function of anything that was worn. probably a early metalurgy issue. why, well, because Ive raced 6 full racing seasons on the same stuff that was in there, less the cams (cams were changed). (oh and new chains which certanly could have been the issue, but they looked fine). point is, should I have changed the tensioners? tensioner pads? heck i finally did buy new cam cover gaskets (o ring) and it leaks now more than it ever did with the used ones!

mk

Originally Posted by blown 87
It just has a few teeth off of the cam gear, it will be fine.
Right Mark.
Old 12-06-2010, 04:35 PM
  #54  
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Originally Posted by Rob Edwards
For a more-or-less stock S4 complete teardown and rebuild, the way I would expect Luan to do it, I get about $7000 in parts alone. And this assumes that all moving parts coming out can go back in. Add a minimum of $7500 to pull, teardown, clean, send out for machine work, reassemble, and reinstall. And then start adding powdercoating, improvements, and slippery slope items. Lightweight lifters? $700. Colin's cams? $1600. A mildly modded 5 liter engine is a $20K exercise, easy peasy.


DESCRIPTION PART NUMBER QTY Unit price Subtotal
SHORT BLOCK
Porsche connecting rod bearings 928 103 143 02 now use 928 103 143 15 8 29.47 235.76
Connecting rod nuts 928 103 172 02 16 2.25 36.00
S4 piston ring sets 928 103 906 28 8 90.00 720.00
MAIN BEARINGS 928 101 901 08 1 303.47 303.47
COMPLETE GASKET SET 928 100 901 04 1 394.84 394.84
M10 LOCK NUTS - GIRDLE TO BLOCK 928 101 741 00 12 3.38 40.56
M12 x 1.5 NUTS for inboard main block studs 928 101 742 00 10 52.10 35.30
DOWEL PIN - straight 6x12 waterpump pin(s)? N 013 199 1 2 0.41 0.82
GTS oil pan baffle 928.107.139.07 1 31.67
Factory OEM water pump 928.106.015.20 1 597.17
waterpump bolts M6x25 - need 8 900.075.341.02 8 1.00 8.00
waterpump bolts M6x20 - need 5 N 010 217 9 5 0.55 2.75
oil pressure sender, sealing ring C48x55, PET #45 900.123.143.70 1 2.79
oil pressure sender, spring, PET #42 928.107.171.01 1 2.52
oil pressure sender, regulator insert, PET #43 928.107.172.02 1 35.23
oil pressure sender, spring, PET #44 928.107.173.01 1 2.52
oil pressure sender, with warning contact PET #46 928.606.203.03 1 102.95
oil pump gear 928.107.107.13 1 60.16 60.16
timing belt 928.105.157.50 1 80.75
Thermostat Housing Inner Seal 84*-95 928.106.163.00 1 $9.19 9.19
oil filter 928.107.201.05 1 8.50
crank gear 928 105 125 12 1 112.95
oil cooler lines rebuilt 210.00
oil pump bolt o-rings, need 3 999.701.006.40 3 0.71 2.13

INTAKE:
brake venturi Y to brake booster 928.110.663.00 1 9.63 9.63
right front cam cover to oil filler 928.107.445.02 1 15.28 15.28
Right Y at air guide elbow to oil filler- GTS 928.107.316.00 1 23.20 23.20
Left Y at air guide elbow to venturi 928.110.224.00 1 14.29 14.29
Left Y ar air guide elbow to Idle Stabilizer valve 928.110.174.09 1 21.75 21.75
ISV to TB housing 928.110.633.00 1 13.04 13.04
3 way hose TB to oil filler and evap vent valve 928.107.603.00 1 29.87 29.87
Left intake side cover to brake venturi 928.110.220.00 1 12.70 12.70
vacuum hose rubber elbows. 928.574.717.02 10 3.06 30.60
airbox rubber donut support things 931.110.191.00 $9.64 19.28
TPS 928 606 157 00 93.11
ISV 928 606 161 01 223.63
MAF refresh 928 606 141 00 175.00
CPS 944 606 115 00 62.00
Knock Sensors 911 606 141 00 2 36.95 73.90
GTS oil neck 928.107.303.09 1 52.30

Tensioner

tensioner boot 83 to 95 928 105 552 08 20.50
tensioner boot clamp 83 to 95 was 999 512 344 02, now 999 512 564 02 2.93
tensioner inner piston o-ring 999 701 650 40 1.92
tensioner arm bushings x2 83-95 928 105 613 04 x2 40.00
tensioner main roller 928 105 512 12 75.00
tensioner adjustment bolt 928 105 075 03 12.49
tensioner idler 928 105 571 04 60.45

HEADS:
Cams- retain stock?
Lindsey racing springs 513.00
Cam gears 928.105.530.01 2 112.00 224.00
cam gear hubs 928.105.459.00 2 19.83 39.66
IWIS Racing cam chains from Roger 2 59.90 59.90
VALVE GUIDES 944.104.327.51 16 6.95 111.20
VALVE SPRINGS 928 105 905 07 32
valve stem seal - need 32 PET #28 928.104.601.07 32 80.00
valve collets- need 64 PET # 33 928.105.221.10 64 0.45 23.68
cam galley plugs -3 for passenger, 2 for driver side 928.105.262.00 5 6.00 4.25
drainback valve spring guide 928.104.119.01 2 10.99 21.98
drainback valve seat 928.104.121.00 2 5.13 10.26
drainback valve compression spring 928.104.129.00 2 0.30 0.60
drainback valve o-ring 999.701.654.40 2 0.58 1.16
drainback valve ball N 025 669 2 2 0.35 0.70
head bolts- M12x 1.5x 199 928 101 231 02 18 9.28 167.04
head bolts- M12 x 1.5 x 149 928 101 233 02 2 14.92 29.84
DOWEL PIN 999.012.034.00 4 5.36 3.76
oil galley freeze plugs 911.101.182.00 8 1.78 14.24
oil galley plug cover N 011 918 1 8 3.28 3.28
CAM TOWER TRIPLE SQUARE BOLTS M8 x35 999.218.023.02 6 $25.20
cam cover bolt sealing rings need 12 900.123.144.30 (or N013 811 2?) 12 $0.18 2.16
cam cover breather fittings- o-rings 900.174.056.40 0.65 2.60
Hose - Left Cam Cover >Right Cam Cover 93-95StrekStrek 928.107.318.00 24.63
chain tensioner repair pads 944.105.949.00 2 209.76
Hall Sensor 944 606 170 01 232.83
engine block to heater valve hose 928.574.567.03 1 8.18

FUEL SYSTEM:
19 LB Injectors Ford 4-pintle 1 250.00
front damper 0 280 161 034 928 110 202 01 154.00
left rear damper 0 280 161 035 930 110 602 01 169.00
fuel pressure regulator 928 110 198 04 169.00
INJECTOR SEAL KITS 928.110.904.00 8 47.68
Fuel line rebuild kit 100.00

IGNITION:
rotors 928 602 213 00 2 16.43 32.86
distributor caps 928 602 211 01 2 24.26 48.52
spark plugs 999 170 156 90 8 2.25 18.00

ACCESSORY BELTS
Air pump belt 12.5 x 925 999 192 306 50 12.00
PS belt 85-95 12.5 x 1000 999 192 286 50 12.00
A/C belts 12.5 x 1080 999 192 335 50 19.00
alternator belt 999-192-266-50 v-belt 12.00

TOTAL 6976.87
Rob, wow thanks for the list, massively helpful as i'm speccing out a rebuild on conjunction with Colin's cams.
Old 12-06-2010, 04:43 PM
  #55  
mark kibort
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my list:
re-use everything, but.... rings, bearings, rod nuts and water pump gasket (and front and rear main seal if you are really ****)
Old 12-06-2010, 04:48 PM
  #56  
Rob Edwards
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You're welcome. As Greg pointed out, I should have added a big asterisk to my list that the prices listed in my post are an amalgam of prices I paid for things at various times over the past five years. Many of these prices are significantly lower than current pricing, all the parts vendors will confirm the capricious nature of Porsche's pricing policies....

Some parts were from Mark, some from Roger, some from Greg, some from DR, and some from Sunset. Betcha you can't tell which ones I got from Greg- the whole point of the post was to A) provide one person's datapoint for reference, flawed and out-of-date as the numbers are, and B) Greg ain't getting rich on his parts markup.
Old 12-06-2010, 05:56 PM
  #57  
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Default ENGINE REBUILD

If ask Rob what do you think of my car 1990s4 he would tell you i had done everything except internally. How funny i was downtown San Diego today and a guy with ownwership of ferraris in his garage offered to buy my car, seeing on the parking meter....he left a business card and as i was ready to leave ; out of nowhere he confronted me about the car...He wants this car...the condition its in and in a red color,as he was checking the interior he stated his Ferraris has yellow stitching,he is ready to pick up another Ferrrari soon...Thinking about selling,so as i was driving somehow i went Porsche dealership and ordered more parts for a rebuild.....cam chains and water pump bolts and the rest for the head soon. Stop by and talked to Porsche tech who works on 928 about Reinz gaskets set,he stated they are good;Reinz makes them for Porsche. Rob we have the 928 hoarding syndrome..
Old 12-06-2010, 06:10 PM
  #58  
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Originally Posted by RED SHARK 1990
i went Porsche dealership and ordered more parts for a rebuild.....cam chains and water pump bolts and the rest for the head soon. ..
You bought your parts at a Porsche dealer?

Now you are just talking crazy.
Old 12-06-2010, 06:11 PM
  #59  
Rob Edwards
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We do indeed, Luan. I am definitely guilty of putting parts up on the shelf for a rainy day! Parts prices aren't going to get any cheaper....

That said, I have to say that with all the stuff you've done in the last year or two (outlined in post #43) that I wouldn't be pulling that engine any time soon. The short block just doesn't need attention at 150K miles. You've already replaced everything that can be rebuilt with the engine in place!
Old 12-06-2010, 07:13 PM
  #60  
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Luan
give that guy my number, want to see if he is interested in a black GTS, or if he is only looking for a red 928


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