Turbo Pistons

[Quick 8]

I'm looking for a piston with about a 13cc dish to get the compression down in a turbo engine I am building. I have heard they are out there, but can not find them anywhere.

Does anybody know the make and part number of 13cc dish pistons?
Any help is greatly appreciated.

Thanks,
Jim

 

[Does10s]

Jim,
JE Pistons can make them for you. They already have the program designed for .040" over forged pistons. You will have to tell them to increase the dish to match you specs.

Mike at www.classicinlines.com can order them for you.
Will

 

[Anonymous]

Before you order dished pistons, spend AS MUCH TIME AS YOU CAN getting the valves unshrouded.
There's quite a few cc's right there (unless you have already done it)

The head design on these sixes is not great.....making it flow better will take away quite a few cc's of cast iron

 

[Anonymous]

Oh yeah.....what CR are you trying to reach?

 

[matt1967]

Ross Racing pistions makes custom Forged pistions. They will make you any pistion you want, and will make a pistion specific to Forced induction. I'm getting the forged Ross Racing Pistions for my 200 I6 build here http://www.campbellenterprises.com/custom_pistons.htm there going to cost $599 with rings and wrist pins, but after jan 1st, there price goes up.

 

[Quick 8]

Thanks for the info guys, but from what I read in the Falcon Performance Handbook, I was under the impression that there was a stock replacement piston with a 13cc dish (not custom piston). I am trying to get to 7.6 Static Compression Ratio. I am trying to maximize the amount of boost I can run on 93 octane.

 

[wallaka]

Probably wouldn't want cast, then.

 

[Anonymous]

I am trying to get to 7.6 Static Compression Ratio. I am trying to maximize the amount of boost I can run on 93 octane.

7.6 to 1 is too low. There isn't any reason at all to run that low. The car will be a dog anytime it isn't in boost.

8.5:1 will still let you run about 8-10-12 psi on 93 octane and will be MUCH more fun to drive. If you want to use a good alcohol injection kit (there are a lot of good reasons to) then you may as well build it at 9-9.5 to 1.

There is also the BTM from MSD which pulls some timing as boost comes up. Not the best way to do things, but it does work. You can find the Vortech branded ones on ebay (still made by MSD but blue, not red) for pretty cheap.

If this is a race car and you are limited to pump gas only by rules, I can see some reasons for the low compression, but if it is a daily driver I see no reason for it. There are too many good ways to manage detonation under boost without having to resort to rediculously low compression ratios.

 

[Quick 8]

I was hoping to run 15psi of boost on 93 octane. According to my research, 7.6 CR should just barely allow me to run 15psi with this engine. Alternately, I was also considering running 9:1, and limiting myself to 7.5 psi on 93, with up to 20psi at the track on race gas.

 

[Anonymous]

15 psi on 93 octane in a 9:1 engine is no problem.
Just spray a little alcohol on it around 8-10 psi and it'll make it to 15 psi just fine.

The buick GN guys are in the upper 20 psi range, maybe even low 30's on 93 octane with alcohol spray

 

[Anonymous]

http://www.turbobuick.com/forums/alcoho ... pane-tech/

 

[Anonymous]

Here you go:

4.3 liters
9:1 compression
91 octane (!)
29 psi of boost

700 HP

http://www.turbobuick.com/forums/alcoho ... t-see.html

 

[Quick 8]

I have looking into water/alcohol some, but I was concerned about the water and alcohol condensing out of the airstream in the intercooler.

Are you suggesting using water/alcohol injection instead of an intercooler? If not, the only place I could see introducing it is after the intercooler, and with the air already being cooled down some, I was concerned that the wat/alc would be atomized, but may not vaporize prior to the carb, and I didn't know what effect (if any) that would have on the carb.

 

[Anlushac11]

8)

The water injection point has to go at the base of carb or somewhere on the intake.

No one usually tries to run a intercooler after the fuel entry point because of the danger of puddling and fire or explosion.

 

[Anonymous]

the only place I could see introducing it is after the intercooler,

Always, always, always

Most people set-up the spray nozzle anywhere from a couple inches to a foot in front of the carb.

The most popular set-ups use a 12v Shur-flo water pump (like from a motor home) with a switch to activate it at a certain pressure (like how my mustang is set up)

A REALLY simple set-up uses a simple washer fluid pump (not normally a really high pressure pump) but a solid designed, sealed reservoir is used and boost pressure is plumbed to the tank to help out the pump.

A washer fluid pump can't spray against boost pressure, but if the pressure is equal on both sides of it it can just fine.

The nozzle doesn't need to be very big. A normal washer fluid nozzle is about 20 times too large. One of the misting nozzles like you see at outdoor cafes on hot days might work. I know they are at Home depot. (I haven't tried one yet) The spray nozzle for the alcohol/water spray on my Ranger is home made and makes a very fine mist. (uses a washer fluid pump)

 

[XFlow_Fairlane]

I have been wanting to go injection but just don't have enough boost for it yet I think. def my plans for the future. the temp drops from injection are such a huge gain from the cost involved (would need a HUGE air/air for the same gains) for nothing more than a tank/pump/nozzle it can't be beat

 

[Anonymous]

the temp drops from injection are such a huge gain from the cost involved (would need a HUGE air/air for the same gains)

Actually, it would be impossible. Lots of folks report intake temps in the sub 70 degree range, where an air-to-air could never reach that alone. That 3000 HP Pontiac was having frost form on the outside of the tubing before the carb.

 

[Quick 8]

So wet flow through the carb from unevaporated wat/alc is a non issue? I was concerned it may interfere with proper gas atomization or booster signal.

Also, how do you determine the correct flow rate of the water/alcohol mixture?

 

[XFlow_Fairlane]

the key thing is a fine spray that will give small enough droplets that they are easily vaporized by the hot aircharge (can be talking as high as 150F) it is not a critical mixture like air/fuel. just spray enough to get the job done. basicly spray and boost come up a little at a time (anyone that dives into 20psi range without easing into it is a fool I think)