January 2010 Project Begins (Raspberry)

[3X00-Modified]

ATI makes them for RWD applications, that's not for a FWD car.

Hypereutectic

Most automotive engines use aluminium pistons that move in an iron cylinder. The average temperature of a piston crown in a gasoline engine during normal operation is typically about 300 °C (570 °F) and the coolant that runs through the engine block is usually regulated at approximately 90 °C (190 °F). Aluminium expands more than iron at this temperature range so for the piston to fit the cylinder properly when at a normal operating temperature, the piston must have a loose fit when cold.

In the 1970s increasing concern over exhaust pollution caused the U.S. government to form the Environmental Protection Agency (EPA) which began passing legislation that forced automobile manufacturers to introduce changes that made their engines to run cleaner. By the late 1980s automobile exhaust pollution had been noticeably improved but more stringent regulations forced car manufacturers to adopt the use of electronically controlled fuel injection and hypereutectic pistons. Regarding pistons, it was discovered that when an engine was cold during start-up, a small amount of fuel became trapped between the piston rings. As the engine warmed up, the piston expanded and expelled this small amount of fuel which added to the amount of unburnt hydrocarbons in the exhaust.

By adding silicon to the piston's alloy, the piston expansion was dramatically reduced. This allowed engineers to specify a much tighter cold-fit between the piston and the cylinder liner. Silicon itself expands less than aluminium but it also acts as an insulator to prevent the aluminium from absorbing as much of the operational heat as it otherwise would. Another benefit of adding silicon is that the piston becomes harder and is less susceptible to scuffing which can occur when a soft aluminium piston is cold-revved in a relatively dry cylinder on start-up or during abnormally high operating temperatures.

The biggest drawback of adding silicon to pistons is that the piston becomes more brittle as the ratio of silicon is added. This makes the piston more susceptible to cracking if the engine experiences pre-ignition or detonation.

NA best may be the 3500 upper since it might broaden your power band range... My spacers have not reduced the heat soak of the upper at all, its feels to be the same temp after the same amount of driving.

[3X00-Modified]

That ATI has no grooves for the serpentine system.

Jon, you had problems with the OEM timing set with a stock cam from the UDP?

"OEM Replacement" aka the parts you get over the counter which are typically told to be of equal or greater quality... The Cloyes set.

The only other OEM set I ran was a 2005 set on the Milzy cam with LS6 springs and the UDP and it stretched the chain badly.. Not sure if that was from the springs or the high RPM's with the UDP.


What it should be

[99GaGT3X00]

if the 3500 uim had more space under it and runners like the 3x00 ones then the spacers would help with heatsoak. with my 1 1/4" spacers it kept the 3400 UIM noticeably cooler vs having it close to the engine.

now dont get me wrong it still got warm to the touch but not as hot as it did without the spacers. for comparison sake its like sticking your hand in luke-warm water VS hot water. plus what ever air that enters the front of the car may pass under the 3400 UIM.

once my carbon fiber SC/T hood gets here i may go back to the 3400 uim since the openings in the hood are open. the way the 3500 uim is made there is no way for the air to travel under it like the 34/3100 uim.

[Money pit Beretta]

Boy I fell for the oldest trick in the book. As said there are no dampers for FWD. That's why I sometimes hate Jeg's and Summit.
The fact that the 3500 doesn't have spaces to let cooling air in is a deal killer for me.
Where did you find all that info 3X00?

[99GaGT3X00]

i havent had my 3500 uim on for long and i was never completely sold on it. i always liked the 3x00 uim better anyway.

[IsaacHayes]

My 3500 plenum gets the same temp as my 3100 did. You can put your hand on it in summer after driving. now shut off the car or let it sit idle and yes it gets too hot to hold your hand on.

[3X00-Modified]

Boy I fell for the oldest trick in the book. As said there are no dampers for FWD. That's why I sometimes hate Jeg's and Summit.
The fact that the 3500 doesn't have spaces to let cooling air in is a deal killer for me.
Where did you find all that info 3X00?

I got that from Wiki, so don't live by it... but it could still all be spot on.

[Money pit Beretta]

I know, I have found one thing that was wrong on there. I told them and they changed it after checking my info. What you got sounds right from what I read in a book long ago. I just didn't remember until I saw it. My brain is almost gone. Did you get any work done?

[3X00-Modified]

I'll go get some pics now... I only worked from 12 till about 4 with lunch sometime in there... I didn't feel like getting up early this AM.

Pics













Took longer than I wanted to get the drive line out but I was also screwing around with my stove and stuff.

Time to get my engine stand to the house so I can start working on the motor now.

[Money pit Beretta]

Damn! I guess you did get some work done. Wish I could get that much done in that amount of time. I work as slow as I type. What brand and stall speed is that converter?
Do you have to remind yourself to take it easy? What's with that "gentle" on the cardboard?

[3X00-Modified]

That's only a FD converter, 2095. I'm debating getting one thats just a bit higher like 2500 or something, but of a factory type.... I've tried and tried flash stall converters and I'm just not impressed with them... The last one I had would end up with a 4500 brake stall... that was WAY too high for me and didn't seem to perform well on the street, it didn't feel like it had much low end grunt.

[Money pit Beretta]

I have the same stall speed now, more or less. I'm going to have to pay someone to put my trans in. I don't want that thing rusting up in the garage. Wow, 4500 is too high! I wanted a 2500, but all I could find were ones for sale for $550. I got my Precision for $150, now I find that they make higher stalls. I will just run this one.

[Barry]

Went to the yard today and saw a Rasbery base 5-speed!

Looks like a good time to start a 5 or 6 speed swap?

[3X00-Modified]

Yeah base 2.2L 5-speed... They never made them in 3.1 versions so its most likely a 4 cylinder.

Its a BAD time to start a 5-speed swap since I can't afford that and have not mastered what I have... There's this thing about modifying something... You should master it before you go and change the configuration drastically otherwise you'll be chasing issues forever. Also as noted I'm not going to ever swap this to a manual... sorry boys but auto's are just better in the 1/4 and on nitrous.

[woody90gtz]

Look at that nasty automatic! It's nice that you have the time and place to do a maintenance teardown. I'd kill for that garage about now.

My 6spd traps higher than your auto... even if I can't launch the damn thing! I feel you on the nitrous though, it does work better with a slushbox. No WOT 0 WOT 0 WOT 0 WOT.