Agreed

 

I've popped two also and the rear turbine was taken out each time. I've also seen several sets of turbos with thrashed wheels personally, and pictures of many more. If you didn't end up with damage to your turbos, count yourself lucky.

Do you think a 2-piece ceramic seal will seal better than a 3-piece stock seal? Improved sealing at low rpm is not a benefit of the ceramic seals to my knowledge.

What would you call better? Another ping or two? I know someone who fragged a set with the engine limited to 10 psi. In fact, they got first hand knowledge of how well they (don't) hold up to detonation by breaking two sets during tuning because the MoTeC harness had some issues. This was at Mandeville's shop, by the way. A few pings more than normal, but not enough to save you from rebuilding the engine or the massive expense of a wasted set of ceramic seals.

Because they think ceramic seals will buy them something that they won't... insurance against detonation and damage to the engine, neither of which is true.

I've wasted a lot of money on my RX-7, but the $1,900 set of Ianetti 3mm 2-piece ceramic seals I bought for the engine that Hayes Rotary butchered for me is still right up there as a contender for most foolish purchase to date.

 

But I'll bet your wallet is thinner as a result...

 

I do consider myself lucky. Maybe you should consider yourself unlucky.

I never said anything about low rpm and besides, who friggin cares what seals better at low rpm. Last time I checked, all the power was made at high rpm's. I don't know a racer who does and/or would put more weight on that vs. high rpm benefits.
The fact is, ceramics are lighter and smoother, creating less friction, less floating and less chatter. This makes them seal better and develop more power than their steel counterparts.

"Another ping or two" just shows you don't know enough about them to be speading misinformation like you are. It's not about if they survive another ping or two, but the the severity of the pinging.
Does mandevilles shop still use ceramics? I don't know, but I bet they do.

Assumption on your part. Some people like the fact that they give more power...along with the benefit of being able to withstand detonation better than steel seals. If they think that ceramics will not destroy everything in their path upon failure, then they are grossly mistaken.

Nothing is, or ever will be impervious to detonation, especially with bad engine builds, poor tuning or other major unforseen problems. Just because you have had a bad experience with them does not mean they are not worth it to those who can afford them.

 

So it's pretty much expected, eh? Better seal, more power, longer lasting, but damn near guaranteed to make you replace your turbos as well when they fail, huh? I guess you can never get the best of both worlds...

 

In that case, there are a lot of other unlucky people around.

In that case, ceramic apex seals seal no better than stock seals.

That's a bit far-fetched. I don't know anyone who has claimed they've made more power solely from adding ceramic apex seals. Maybe you should talk to Francesco Ianetti and ask him what the real benefits of ceramic seals are.

Do you know what detonation does to combustion chamber pressure? Ceramic seals are no silver bullet to use against detonation, contrary to what you've been misled into believing.

From talking to Roger Mandeville, they withstood a couple more pings (his exact words) than standard seals, but broke nearly as easily. 2 sets were broken in the tuning of Sandy Linthicum's engine @ 10 psi. Once the faulty harness was replaced and the engine was final tuned, Sandy popped the third set several months later. Still at 10 psi.

You seem to have overlooked making a few of your own...

I didn't have a bad experience with them. I'm simply smart enough to know what the real world benefits are and weigh them against the cost. Excuse me for trying to save David a few dollars.

 

Don't believe everything you read on this forum...

 

My thoughts exactly

 

Wrong. Do you know what the characteristics of the apex seals are as they travel over the surface of the rotor housing? Do you know what floating is?
Do you know that floating is not good for sealing? Did you know ceramics reduce floating and chatter. Have you compared rotor housings between steel and cermics? Have you seen the difference? Are you as stubborn as I am?
Haven't talked to Iannetti, but have talked extensively to Sven from NRS. Perhaps you should also.
Allow me to be the first to tell you. We run 20-25 Star Mazda cars from our shop (depending on how many are wrecked). These cars are tuned/restricted to be exactly the same in power. We test them once a month down a 1/4 mile strip (Sears Point) to ensure this before every race weekend. We put ceramics in two cars and had to make new restrictor plates between the upper and lower manifolds to slow them down enough to be equal with the other cars as none of the restrictors we had were large enough. I think the ceramics might have had something to do with that, but then again, I am making an assumption.
Yes I do. Detonation occurs when excessive heat and pressure in the combustion chamber cause the air/fuel mixture to auto-ignite. This produces multiple flame fronts within the combustion chamber instead of a single flame kernel. When these multiple flames collide, they do so with explosive force that produces a sudden rise in cylinder pressure accompanied by a sharp metallic pinging or knocking noise. The hammer-like shock waves created by detonation subject teh seals to extreme overloading.
I never claimed that and specifically said they are not immune to failure. Your eyes or comprehension skills have mislead you.
So what if those were his exact words. I didn't know he was such an authority as yourself when it comes to ceramic seals. Besides, there are many other people out there with different experiences.
Hint: Not everything is meant to be taken literally. <-- Assumption on my part
Shouldn't you be trying to finnish that car of yours? <--Meant to be taken literally.
Touche'
There you go making assumptions again.
Perhaps you haven't seen the car in your garage. As nice as it is, that has got to be the worst example of real world benefits vs. cost.

 

Weak, not to mention that "touche" was inappropriate in the context in which you used it.

It's quite obvious that you've got a personal issue with me, especially since you've taken some catty swipes at me in other threads, but rather than continuing to post your garbage in this one, why don't you just resolve to dislike me silently.

David, buy whatever you want.

 

why don't all of you just stfu and let this guy make decisions for himself, and let him run his own post. this has nothing to do with the original post.

face it, youre not arguing facts, youre arguing opinions and hear-say. it's worthless.

 

ceramics > pistons


haha, argue over that girls

 

AMEN. It's gotten to the point that I don't even want to follow this thread anymore!!

 

For you guys think you poped your engine without damaging the turbine wheel all I can say is if a peice of apex seal broke off (even a tip) more than likely you trashed your wheel. You cant tell if its been trashed or not unless you remove the turbine housing where you can see the entire wheel, shaft, and everything. If you didnt remove the housing then you dont really know if it was trashed or not.

STEPHEN

 

Good point.

I used to run hurleys, which blew up 5 (FIVE!) times on me before i learned my lesson. They never damaged a damn thing in the motor and turbos, though.....

 

Okay,

I went with the 3MM metal ones. The engine has been pulled (available for sale:Pettit street-ported) as well as all other non-20b parts (intercooler, etc.). The new 20B has been rebuilt and put back together. As of this morning, Pettit is working on "plumbing" the new 20b (hoses, wires, etc.). This should be done in a day or two and the engine should be ready to be installed by the end of the week. Next week, Pettit will install the new intercooler as well as all other order parts (big brake package, etc.). Will post pics and a list of the new stuff soon.

 

Best of luck with your 20B David. Many of us would love to be in your shoes right now.
I had a chance to visit Pettit Racing last year. They gave me a full tour of the shop and Cam let my sons into the dyno booth while they tested a (911GT) for 24 hrs of Daytona shooting huge flames... Kids loved it

Keep the updates coming

//Oliver

 

Is yours the one with stock rims and all stock body?
Black?

I saw it while in there today. I was trying to explain to my woman about the 20b being the BIG engine swap. Good luck.


Raj

 

Mine is black, but I don't have stock rims. They're 5 spoke RO_JAs. They may be off the car now though as I think a person was interested in buying them (they're for sale - can't get a 12.5" width so I had to take them off).

If you saw my car, the engine would be out, and the front end (Pettit 99 spec front end) would be removed.

Tyler, Pettit mechanic, has taken pics and has promised to send them to me. I'll bug him again today!

 

What kind of intercooler did you have? Is it for sale?

 

Holy Crap David, your going all out, with the bigger brakes, etc. I can't wait to see her when ya get her back!

 

Jim do you happen to know what the weight is for your completed 396 and a completely built 20B engine?

 

My engine wasn't weighed as I requested prior to being shipped, so I only have the estimate for the crate, which included a twin disk clutch with a steel flywheel (~65 lbs.) and a few other odds and ends of parts. The estimated shipping weight was 475 lbs., but I don't have the means to weigh the engine separately, and didn't weigh the plastic engine crate itself. My 20B was 525 on its wooden pallet, so even subtracting the pallet, it was still considerably heavier.

Peter Farrell stated that the 20B weighed about 130 lbs. more than the 13B-REW, and Jeff Hoskinson weighed his truck on a very accurate truck scale with and without a complete 13B-REW with turbos and accessories and came up with 430 lbs. IIRC, so a 20B could be 500-550 lbs. depending on the configuration. That weight sits farther forward in the car than the LT1 does also.

 

Still no pics to post yet. Will do my best.

I did want to post the work (and parts) that are part of the Pettit 20b conversion:

- Rebuild and street port 20b, including blueprinting and ceramic coat turbos
- New rotor housings
- Pettit 20b subframe
- front strut tower brace
- sway bar spacers
- 6 ignition coils with ignitor
- 20b wires
- 20b fuel injectors
- battery relocation kit
- aluminum radiator
- dual electric fans
- 20b aluminum air separator tank
- upper and lower radiator mounts
- welded upper elbow
- lower hose connector and thermostat
- coolant hose kit
- aluminum radiator cover
- custom pulleys and belts
- clamp fitting kit
- 20b oil cooler kit
- charge pipe intake
- charge pipe with flange
- charge pipe out
- 20b front mount intercooler
- primary fuel adapter
- secondary inlet pipe
- throttle body adapter
- transition pipe
- engine management system (left the choice up to Cam)
- fabrication and installation of parts
- TKT clutch kit
- all new fluids
- fuel filter
- shift floor board boot
- modified front spindels
- NKG spark plugs
- exhaust, resonating center section
- big brake kit
- pro launch kit
- front sway bar
- installation of suspension and brakes
- tuning and dyno testing


In addition to the above, I've added Forgeline WC3 wheels, Apexi side skirts, and Pettit rear flares. I'm also having the car re-painted.

Other than that, not much is changing!

 

Good luck! Sounds like a good women.