EBS Cylinders

[blue82coupe]

Has anyone tried the EBS 95mm to 98 mm bored and re-nicasiled cylinders and JE pistons? I'm considering these for my 3.0 to 3.2 short stroke build-up. Any info would be appreciated.Dan

[ChrisBennet]

EBS is great. I am in the middle of building up a 3.2 short stroker for a customer using their 98mm P&C right now. I don't think it is EBS's fault but the 2 sets of "9.5:1" JE's I bought from EBS both CC'd out to 10.5:1. I'm going to machine them down to 9.5:1 tomorrow. If the project wasn't so far along it would be perfect excuse to go with the twin plugs solution BURN-BROS is selling.
(Twin Plug Goodness...Look what I made this weekend!)
-Chris

[Jeff Alton]

Chris can you post before and after pics of the pistons?? I would like to see what they look like after machining. Is there a part number on them that indicates their compression ratio?

Jeff

[ChrisBennet]

Originally posted by catca
Chris can you post before and after pics of the pistons?? I would like to see what they look like after machining. Is there a part number on them that indicates their compression ratio?

Jeff

I'll bring my camera. There is nothing on the piston to indicate compression. They use the same casting as the 3.4 (3.2->3.4) pistons but are a different shape. According to JE, these are the dome volumes for the SC 98mm pistons:
10.5:1 -> ~41.7cc
9.5:1 -> ~35.2cc
Mine measured out to 39.5cc
-Chris

[blue82coupe]

Thanks Chris. It's my intent to go the hi-comp, twin plug route.I've been trying to find negative comments about EBS .. so far I havn't found any... Chris how are they with other machining operations? Is it done in house, or sent out?Dan

[ChrisBennet]

I haven't used EBS for machining so I don't have any personal experience but I *think* they have a good rep. They send their stuff out AFIK
-Chris
EDIT: I forgot, the customer supplied rods were done by EBS and they look good but I didn't measure them. I know I should have but they felt good on the crank..
-Chris

[blue82coupe]

Chris ,since were on the subject .. who do you recommend for machining operations. Such as rod rebuilding, head work and balancing. Dan

[nate3.4]

installing 3.2 to 3.4 EBS re-nicasils now. I'm hopeful.

[ChrisBennet]

Originally posted by blue82coupe
Chris ,since were on the subject .. who do you recommend for machining operations. Such as rod rebuilding, head work and balancing. Dan

I send my heads to (Anchor) Atlantic Enterprises. He advertises in the back of Excellence. I have a local machinist do everything else.
-Chris

[blue82coupe]

Again ...thanks. That reinforces my plan of sending the heads to a Porsche specialist and the other parts to my local machinist.Dan

[ChrisBennet]

Originally posted by blue82coupe
Again ...thanks. That reinforces my plan of sending the heads to a Porsche specialist and the other parts to my local machinist.Dan

Rods are rods pretty much but if you need the case machined you need to know enough that you can guide your local guy or use a machinist familiar with Porsche work. EBS was less than $10 more expensive than having the local guy do rods so going local isn't necessarily a price savings.
-Chris

[JeremyD]

I'm going the 3.4 route myself - although I bought Eric Hood's c2 turbo cylinders that had been bored to 98mm.

[vntgspd]

I just finished getting my 2.4 back together yesterday. Started right up and runs well.

I used EBS for all of the hardware purchases and Ollie's Machining in Santa Ana, CA (both advertise in mags). I can't say enough about both of these companies. They were very knowledgable and helpful. The prices were very fair and neither of them tried to sell me anything I didn't need. In fact, Ollie's went out of their way to allow a DIY'er such as myself to do a few things with their direction that saved me about $400.

Both delivered everything correctly, on time, and as promised.

Good luck with your project!

[ChrisBennet]

Originally posted by catca
Chris can you post before and after pics of the pistons?? I would like to see what they look like after machining. Is there a part number on them that indicates their compression ratio?

Jeff

Hey Jeff,
Here you go. As you can see, very little was removed.
The "Before" piston is the one on the left.



I weighed a piston. Then my friend Palmer took a few passes with the mill, matching the original angle of the top. Then we checked the dome volume, and repeated the process until got the compression I was looking for. We compared the after machining weight to the premachiing weight to determine how much material was removed. For the rest of the pistons we simply removed the same amount of material (by weight) from the top.

Dome volume before: ~39.5cc, compression 10.5:1
Dome volume after: ~33.2cc, compression ~9.6:1
Material removed 5.7 grams
(Deck height=1mm, head vol=87.8cc)

This motor will be running with knock sensing so I picked a compression on that was conservative yet fun to be around.
-Chris