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Discussion Starter #41
Larry, you have around 3 weeks left!! Is everything on track???
I hope!!! I'm waiting for a call back from ARP Bolts but I'm not too optimistic about it since they don't have it in our size for our rods so I ordered a new set of rod bolt set from the dealership.

The custom designed forged pistons are coming in soon as well as my new flywheel, kevlar steel backed clutch and modified pressure plate setup.

Changing the press in wrist pin in rod to a floating wrist pin setup which is more ideal and better especially in a forced induction engine.

All the rod, crank / main bearings are in as well as a new head gasket. A lot of things were special ordered thru the dealership for this rebuild.

Wanted to get Ferrea valves but they are not actually available yet :)...

Larry
 

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Very exciting news! I can't wait to see what you are doing for a flywheel since it could have a major effect on shift speed and lower gear acceleration. Since our cars release the clutch at such a low rpm when launching, the engine has to drag the heavy flywheel through the whole power band on first gear.
 

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Discussion Starter #43
Very exciting news! I can't wait to see what you are doing for a flywheel since it could have a major effect on shift speed and lower gear acceleration. Since our cars release the clutch at such a low rpm when launching, the engine has to drag the heavy flywheel through the whole power band on first gear.
Thanks! Actually the engine isn't dragging the heavy flywheel through the whole power band, the flywheel as you know is there to store kinetic energy that is to be released to help propel the car forward. I wanted a lighter flywheel for a few different reasons...

-Allows the engine to rev up faster thru it's range
-Allows the engine to rev down faster to enable quicker gear changes (just like how the gear actually shifts slightly faster with the A/C on as the Air conditioning compressor increases drag and pulls the rpm down faster)
-Allows a much higher safety margin when I eventually increase the red line on the ECU... I would not risk my life to the cast iron factory flywheel exploding. Look up on youtube on flywheel exploding to see what I mean =P

However the flywheel can't be too light either...

Anyways it's a whole package deal.. flywheel, clutch and pressure plate setup with a new throw out bearing :) Something I can offer to the smart community as well even though it's not cheap =P...

The engine also is getting bumped up from 10:1 to 10.5:1 compression ratio for even higher efficiency and more power when NOT in boost. This increase comes from having a larger bore and large pistons to fill that bore. I could have maintain the same compression ratio or lower it but I decided to keep it higher instead. The difference is with a higher compression ratio, the margin of error in tuning a force induction engine becomes much smaller. Since I had the engine tuned fairly well prior to all this, I took the chance and instead of maintaining, I decided to up the compression ratio even more ;)...

My ultimate crazy goal will be to try to run as much boost as I did prior to this whole rebuild and since the octane of the fuel was the limitation before, I'm hoping anti denotation grooves on the piston, forged pistons, lower over all operating temp on the engine and a few other tricks will allow me to run the same amount of boost on pump gas :)

Larry
 

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Discussion Starter #44 (Edited)
Finally... my custom made, special designed FORGED pistons are made to my specifications and delivered to my door steps :).. Too tired to do all the explaining but I'll post pictures first ;)... Oh... And the first ever to have a high performance chromoly flywheel, performance pressure plate and kevlar steel backed clutch plate with a new direct replacement release bearing.

Flywheel is 25% lighter then stock but most importantly stronger, not cast iron so I wont have to worry about a lethal exploding flywheel in the future.

Pressure plate is increased from stock 800 lbs of force to 1200 lbs without any increase of force in the release pressure!

With a new pressure plate (not a modified factory unit) comes with a new release bearing that is a direct fit into our clutch fork! The only way to obtain the Factory SMART OEM release bearing is to buy the WHOLE release bearing WITH the clutch fork! No thanks :)

The ring gear is machined onto the flywheel, not pressed on.













Larry
 

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Very nice Larry! One off flywheel?
Interested on the effect it will have on shift speed, I hope it shortens shift time.
 

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Larry, what did you go with as far as C/R on the new pistons? And, why didn't you have the pistons made as floaters? They look like they're still a press fit pin in the PICS.
 

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Discussion Starter #49
Very nice Larry! One off flywheel?
Interested on the effect it will have on shift speed, I hope it shortens shift time.
It's the first one but not a one off and this setup should shorten the shift time because the transmission shifts when the rpm is dropped down to the right shifting range. The faster that engine can drop it's rpm when it's time to shift, the quicker the transmission can start to shift it's gears. :) Just like when Gearhead mentioned before, if you run with the A/C on, your car shifts just a tad quicker then if you had it off becuase the A/C applies drag to the engine to drag the rpm down quicker.

Larry, what did you go with as far as C/R on the new pistons? And, why didn't you have the pistons made as floaters? They look like they're still a press fit pin in the PICS.
I bumped up the C/R up naturally to 10.5 to 1. This was a natural effect as I oversized the pistons and bored out the engine. I debated about keeping the compression ratio as factory, raising it up or lowering it down. After a whole month of thinking, discussing and debating I kept it at 10.5 to 1 so I can have more lower end grunt when I'm not in boost, get more power.. and the real downside is that as you increase the compression ratio you just narrow the margin of error as far as tuning is concerned. However since I have the tuning pretty much dialed in before I took the engine part, I should be safe when I first start up the engine. Obviously I still have to retune it but I'm okay with a narrower tuning margin. :)

As far as making the pistons as floaters, they are. The wrist pin floats and isn't pressed in like stock. If you look at this picture below... you can see a groove machined inside where the wrist pin slides into and that groove is used to hold a retainer that keeps the wrist pin from coming out. The main issue floater was.. getting the rods smaller end to be machined to press in a sleeve and have it honed out. There's not much meat in that rod where I feel comfortable to machining the hole larger and pressing a sleeve in. However after discussing with the machinist and others that are expert in the area, I can just have the smaller end of the rod honed out instead so the wrist pin wont have to be pressed in but instead will slide. The other issue was finding out HOW much larger to hone that hole to because due to metal expansion rate I didn't want the wrist pin to seize up since the wrist pin and rod are both steel compared to a steel wrist pin inside a bronze sleeve or something.

The factory pistons have the wrist pin pressed into the rod and it rotates freely in the aluminum piston.



Larry
 

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I bumped up the C/R up naturally to 10.5 to 1. This was a natural effect as I oversized the pistons and bored out the engine. I debated about keeping the compression ratio as factory, raising it up or lowering it down. After a whole month of thinking, discussing and debating I kept it at 10.5 to 1 so I can have more lower end grunt when I'm not in boost, get more power.. and the real downside is that as you increase the compression ratio you just narrow the margin of error as far as tuning is concerned. However since I have the tuning pretty much dialed in before I took the engine part, I should be safe when I first start up the engine. Obviously I still have to retune it but I'm okay with a narrower tuning margin. :)

As far as making the pistons as floaters, they are. The wrist pin floats and isn't pressed in like stock. If you look at this picture below... you can see a groove machined inside where the wrist pin slides into and that groove is used to hold a retainer that keeps the wrist pin from coming out. The main issue floater was.. getting the rods smaller end to be machined to press in a sleeve and have it honed out. There's not much meat in that rod where I feel comfortable to machining the hole larger and pressing a sleeve in. However after discussing with the machinist and others that are expert in the area, I can just have the smaller end of the rod honed out instead so the wrist pin wont have to be pressed in but instead will slide. The other issue was finding out HOW much larger to hone that hole to because due to metal expansion rate I didn't want the wrist pin to seize up since the wrist pin and rod are both steel compared to a steel wrist pin inside a bronze sleeve or something.

The factory pistons have the wrist pin pressed into the rod and it rotates freely in the aluminum piston.



Larry
Ahh I can see it now that I'm on my PC! I really need to get a new cell phone with a bigger display.
 

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Larry, Hope these pics were taken about a week or two ago !

Those pistons better be inside the block by now.Time is getting thin!
 

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Well.............?
Got Milk?
Is it Cow....Now?
How about NOW?
Need more devil cow car porn! I NEED IT! going into withdrawal...
smart minds need to know!
 

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Discussion Starter #56
Well.............?
Got Milk?
Is it Cow....Now?
How about NOW?
Need more devil cow car porn! I NEED IT! going into withdrawal...
smart minds need to know!
Here's your porn.. =P...

Engine block fresh from the machine shop! Bored out to the extreme! Any larger and I wont have much of a steel sleeve left!





Here the stock pistons are sitting butt to butt on top of the new forged ones! Look how much larger they are =P... Normally engines that get rebuild or etc are bored out 10.. 20.. 30 thous of an inch, this is like.. 80.. 90 thou!



The stock pistons half way into the new bore... look! So much extra room ;)... POWER!!! Boom Boom POW!



Thank god the sleeves are not tapered! View from the bottom... it might look like a lot of steel thickness left but trust me, there's not THAT much left... I just zoomed up very close :) But.. no worries! There is enough left to be safe :)



Another view from the bottom... you can see where the steel sleeve ends and where the aluminum block starts.



Going to a FULL floating pin setup! Requires the small end of the bore be honed out to fit the new wrist pins! There's not enough meat on the small end to bore and press in a bronze bushing but if.. IF I ever do have to replace the rods due to wear I'll just replace the rods themselves.. no biggie so.. steel wrist pin in steel bore! Sounds like.. full metal jacket.. lol..

Oh and a small hole has to be drilled and chamfered on the least stressed part of rod which would be the very top of it. The best would be to use a EDM and make two holes directly thru the rod from the big end to the small end but if that's the case I would have spent money on getting brand new aftermarket rods like titanium rods or turn it into a stroker or something =P...



Don't wet yourself now BB Benz ;)... Hope the rest of you guys can appreciate this as much as I have been! A lot of $$$, time and effort has been going into this... has less to do with the money and more to do with doing something different with the factory engine and just amazing how much power I was able to put out of the stock engine BEFORE I tore it apart!

Next up... the whole rotating assembly has to be balanced since the pistons are forged and they are heavier then stock.

Larry
 

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Discussion Starter #58
So.. I was thinking... it would be so cool to have a supercharger blowing into a turbocharger for instant gratification..

Could mount a procharger on the same side.. lower the engine and transmission for lower center gravity.. and I could also remove the factory water pump and use a high performance electric water pump.. .hmm... the ideas.. ideas.. ideas...

Unfortunately due to not being able to get parts on time from the dealer such as certain critical bolts.. I wont be able to make the nationals ;(... For example I order new connecting rod bolts from the dealer on the 12th of last month.. They are still not in stock... ;( And ARP doesn't make a set in the small size that are used in our engine...

I guess this means you will blue print this engine?
Exactly... Unfortunately the pistons can't get lighter since they are forged and not cast like stock but the slightly higher compression ratio, the lighter flywheel definitely helps :)

Larry
 

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Discussion Starter #60
I'm saddened you will not be making the trip. Was looking forward to seeing the cow mooooo!!!!:(
Yea ;( Me too... The car has been out of commission for more then 3 months and I'm so deprived of my car! It's just sad I'm waiting for bits and pieces.. I'm so tempted to reuse the bolts but I know they are cheap insurance and I am not and can not reuse any of those critical bolts. I wish there was a supply of them elsewhere...

Shoot me an e-mail barney, would love to talk to you about something. my email is my username @gmail.com :)

Larry
 
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