Top Fuel Piston and Rod Assembly

[wwillson]

My friend, who owns is own shop, socializes with one of the Top Fuel drivers when he's in town for the Route 66 Nationals. The driver brought this to my friend as a souvenir. It made several passes down the track while cranking out over 1,000 HP by itself. I had never held a top fuel piston assembly in my hand and we surprised how stout they are.

 

[ls1mike]

That thing is serious. Was it heavy?

 

[SEMI_287]

Holy smokes! That's like a heavy duty diesel!

 

[wwillson]

Originally Posted by ls1mike

That thing is serious. Was it heavy?

Yes, that's a LOT of weight swinging around at high RPMs.

 

[CR94]

What metal is it?

 

[wwillson]

The pin in rod cap is to keep the bearing from spinning!

 

[02SE]

Ready to drop the rack in.

 

[wwillson]

Originally Posted by SEMI_287

Holy smokes! That's like a heavy duty diesel!

I think it's much heavier duty than a modern diesel assembly.

 

[spasm3]

Trying to look close, but is it a fractured rod cap design?

 

[02SE]

Originally Posted by CR94

What metal is it?

Aluminum. The specific alloy varies depending on what is thought to work best.

 

[sloinker]

Originally Posted by spasm3

Trying to look close, but is it a fractured rod cap design?

If it isn't now just give it a couple runs.

 

[bdcardinal]

Originally Posted by 02SE

Originally Posted by CR94

What metal is it?

Aluminum. The specific alloy varies depending on what is thought to work best.

Is CP Carrillo still the preferred vendor?

 

[hatt]

Those engines are amazing.

 

[02SE]

Originally Posted by bdcardinal

Originally Posted by 02SE

Originally Posted by CR94

What metal is it?

Aluminum. The specific alloy varies depending on what is thought to work best.

Is CP Carrillo still the preferred vendor?

Brooks, Venolia, BME, AJPE made by Venolia. There have been several others.

 

[CT8]

There are several you tube videos that explain the top to bottom of how top fuel engines work . It is amazing !! I would call it evil voodoo.

 

[02SE]

Originally Posted by bdcardinal

Originally Posted by 02SE

Originally Posted by CR94

What metal is it?

Aluminum. The specific alloy varies depending on what is thought to work best.

Is CP Carrillo still the preferred vendor?

Sorry, I should have explained. Brooks was a favorite. Venolia are MY preferred.

 

[ragtoplvr]

I did not know the piston was capable of more than one run. I know they get rebuilt after every run, nothing lasts very long on those engines. Is the piston aluminum with diamond like coating? Rod

 

[beechcraftted]

I once had a top fuel crew member explain to me why the pistons were replaced so often (they looked good to me as this one does). He stated that the very high combustion forces actually press the dome of the piston down, causing the upper ring land to close up. It has to be replaced before the top ring breaks. Note how far down the upper ring groove is compared to modern gasoline engines. That piston has lived a hard life.

 

[ZeeOSix]

Originally Posted by beechcraftted

I once had a top fuel crew member explain to me why the pistons were replaced so often (they looked good to me as this one does). He stated that the very high combustion forces actually press the dome of the piston down, causing the upper ring land to close up. It has to be replaced before the top ring breaks. Note how far down the upper ring groove is compared to modern gasoline engines. That piston has lived a hard life.

Yep, that first ring groove is really down from the piston crown. Makes sense. Is that 3rd wide groove down from the top actually for a ring, being that it cuts across the wrist pin?

 

[02SE]

Originally Posted by ZeeOSix

Originally Posted by beechcraftted

I once had a top fuel crew member explain to me why the pistons were replaced so often (they looked good to me as this one does). He stated that the very high combustion forces actually press the dome of the piston down, causing the upper ring land to close up. It has to be replaced before the top ring breaks. Note how far down the upper ring groove is compared to modern gasoline engines. That piston has lived a hard life.

Yep, that first ring groove is really down from the piston crown. Makes sense. Is that 3rd wide groove down from the top actually for a ring, being that it cuts across the wrist pin?

Look at the pic I posted of the rack ready to be installed, from one of the past teams I worked on. It is for the oil control ring. The wristpin is inboard as you see in the OPs pic. What you can see installed in my pic are called 'buttons' which keep the wristpin centered. They are clearanced for the oil control rings.