question 2.7 Sleeved block
#17
While JE may not be the best option available now, they will work. IMHO it has more to do with correct piston to cylinder wall clearance, ring gaps and ring material my JE's have done great for the last 10 years using chromolly sleeves
#18
My comments were based on precedence. They were also based on someone else starting from scratch and that's why I suggested to use a different piston. It was a generalisation. I'm sure you could get the JEs to work but they will require plenty of piston to wall clearance and therefore expect them to be a bit noisy on startup until they expand. They're known colloquially as 'Rattlers' for a reason.
#19
I agree Patrick and if I were to build another I would choose something besides JE as there are options now that I did not have back in the day. 6 thou piston clearance mine is as smooth and quite as stock even without balance shafts
#21
Hmmmm, I want this... All ready sent Luis a pm. But I am a novice when it comes to sleeving. So this would be a 'dry' sleeved block (sleeves pressed into stock cylinders)? As opposed to a 'wet' sleeved block, which would replace the entire cylinder? All the talk about the J&E pistons has me worried some too. What would a different set of pistons run for this application and how readily available are they?
#23
once pon a time I bought a 2.8L with J&E which had problems
https://rennlist.com/forums/5364478-post153.html
https://rennlist.com/forums/5364478-post153.html
Do you really think forged 2618 pistons from JE are really any different than forged 2618 from Wossner, Ross, or any other top piston maker? The 2618 forged pistons will expand a little more than the 4032. The 2618 is stronger and better suited for higher boost levels.
That looks like your builder got the clearances wrong. Being off just .001 and you could get what you see. The differences in wall clearance when using 2618 vs 4032 is tiny. But, if the builder doesn't allow for expansion, you may get the scuffing you see in the photo.
I, personally, would not use anything but the exact metal used in the factory engines when using the stock bores. Coating for these applications scare me, and I simply would not do it. I know, "It a proven system." I don't think it's worth the risk.
This motor is steel sleeved, as long as it's built right any 2618 or 4032 forged piston and ring set designed for steel will work fine.
JE has been building custom forged pistons for the racing community for OVER 60 years with a long line of engine builders, Pro race teams, and engineers that use JE pistons in their builds.
These motors require skill to custom build. We are not building Chevy 350 V8's or air cooled VW motors here. You mess up the build on a 500 to 600 2.7 to 3.1four banger, you are going to have issues.
I AM NOT an engine builder. I am very involved in my projects though. I don't have the time to do this work, but I'm sincerely interested and have learned a great deal over my 20 years driving the **** out of various sports cars.
Off my chest...thanks for listening.
#24
By the way, I have no noise starting cold. One of my friends had a 3.0 motor built. At cold start up, he thought he heard noticable piston slap. When I heard it, I knew it was his solid lifters and not his pistons. His motor was built using JE pistons from a repuatable shop.
#26
Custom built 2618 forged pistons. JE, www.uschrome.com, and my engine builder, Garrity Repta, worked together to make sure the piston sizing to bore size were exact.
Garrity used to teach the PCA engine building classes for PCA. Some of the listers that have done their own 3.0 builds went to his classes.
Garrity used to teach the PCA engine building classes for PCA. Some of the listers that have done their own 3.0 builds went to his classes.
#27
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Custom built 2618 forged pistons. JE, www.uschrome.com, and my engine builder, Garrity Repta, worked together to make sure the piston sizing to bore size were exact.
Garrity used to teach the PCA engine building classes for PCA. Some of the listers that have done their own 3.0 builds went to his classes.
Garrity used to teach the PCA engine building classes for PCA. Some of the listers that have done their own 3.0 builds went to his classes.
#28
Come on Lart, that's what you pay me for my old worn stuff.
The really expensive part is when you have to build your motor again because it was done WRONG. This comes from experience. Lessons should teach you how to do things differently so they are not repeated. I've kept the same daily driver mechanic for over 25 years. I completely trust him.
Garrity Repta has as much experience as any Porsche shop. He is also a mechanical engineer with decades of experience with these motors. He was making deck plates over 20 years ago for these engines for race cars.
The really expensive part is when you have to build your motor again because it was done WRONG. This comes from experience. Lessons should teach you how to do things differently so they are not repeated. I've kept the same daily driver mechanic for over 25 years. I completely trust him.
Garrity Repta has as much experience as any Porsche shop. He is also a mechanical engineer with decades of experience with these motors. He was making deck plates over 20 years ago for these engines for race cars.
#29
This may be of interest. My block was sent to US Chrome, and JE sent US Chrome the pistons based on what US Chrome told JE. The pistons were manufactured by JE and sent to US Chrome.
US Chrome then made sure each bore was matched to the pistons as decided by the three "experts".
Here is a good write-up about NiCom. NiCom was designed by Porsche, not US Chrome.
(NiCom® is U.S. Chrome Corporation's name for the nickel-silicon carbide coating often referred to as “Nikasil®”)
NiCom® is applied directly to aluminum bores through an electro-chemical plating process.
Since the NiCom® coating is thin (.003-.005”), heat transfer from piston to cylinder block is superior, drawing heat out of pistons more efficiently, making engine less prone to detonation (knocking or “pinging”) which can cause catastrophic damage. Heat transfer with this technology is more efficient even than an aluminum block with iron liners because although the liners typically have a ground surface finish and a tight press fit to the aluminum block, there is a barrier to heat transfer at that interface that is virtually non-existent with the NiCom® plated bores.
Another benefit is that the coefficient of expansion of the cylinder block is very close to that of the piston. This allows us to use tighter piston clearance than would be used with an iron block or an aluminum block with iron liners. The tighter clearance means better combustion chamber sealing, reducing blow-by and increasing power.
NiCom® has a composite hardness of 58 Rockwell-C and thus has far superior wear resistance when compared to cast iron. It is also repairable. In the event of damage to the bore the NiCom® can be stripped, re-plated and honed to the original spec. If the score or gouge is very deep the aluminum can be re-bored and then the NiCom® re-applied and an oversize piston fitted.
US Chrome then made sure each bore was matched to the pistons as decided by the three "experts".
Here is a good write-up about NiCom. NiCom was designed by Porsche, not US Chrome.
(NiCom® is U.S. Chrome Corporation's name for the nickel-silicon carbide coating often referred to as “Nikasil®”)
NiCom® is applied directly to aluminum bores through an electro-chemical plating process.
Since the NiCom® coating is thin (.003-.005”), heat transfer from piston to cylinder block is superior, drawing heat out of pistons more efficiently, making engine less prone to detonation (knocking or “pinging”) which can cause catastrophic damage. Heat transfer with this technology is more efficient even than an aluminum block with iron liners because although the liners typically have a ground surface finish and a tight press fit to the aluminum block, there is a barrier to heat transfer at that interface that is virtually non-existent with the NiCom® plated bores.
Another benefit is that the coefficient of expansion of the cylinder block is very close to that of the piston. This allows us to use tighter piston clearance than would be used with an iron block or an aluminum block with iron liners. The tighter clearance means better combustion chamber sealing, reducing blow-by and increasing power.
NiCom® has a composite hardness of 58 Rockwell-C and thus has far superior wear resistance when compared to cast iron. It is also repairable. In the event of damage to the bore the NiCom® can be stripped, re-plated and honed to the original spec. If the score or gouge is very deep the aluminum can be re-bored and then the NiCom® re-applied and an oversize piston fitted.
#30
Isn't there a history on the head gasket leaking on this engine? I would strongly recommend that any issue with the engine be brought up so that the new owner has a chance to look at it and correct the issue.