Wiseco problems

[Biggy72]

I was just wondering if there is anyone else having trouble with Wiseco right now. I was trying to get some custom pistons made for our f4i with a turbo this year and I was working with Jeff Clarkin, but I have had a really difficult time actually getting ahold of him. He never answers his phone or returns voicemails or emails. I sent another email to the main email listed on the wiseco site, but I haven't heard anything back from them either.

I really want to get stuff rolling and at one time he told me there would be a month lead time, but if I can't finalize the specs of the pistons I'm not sure how they are supposed to start cutting them.

[rjwoods77]

It is the vacation and holiday season. They may have been shut down like most companies for two weeks and are flooded with emails and work for real customers. Just make sure you dont have a bad "tone" in your email. Customers get caught up in situations like this all the time and it is kind of funny to watch the progression of email frustration. Call Wiseco and ask to talk to customer service and describe your problem. It is probably what I described.

[JamesWolak]

I had the same issues with Jeff earlier in the year. I must have called him 3 times a week for a month. I finally got a hold of him by calling someone else and complaining. Wiseco is hit or miss period i called once and had my parts the next day, a couple weeks later i went to order the same parts it took them a week just to get the order processed.

As for custom pistons Wiseco wasn't as willing as JE was. In the past we used JE for custom pistons and had no issues.

Hope this helps

[Biggy72]

When I initially started out looking for custom pistons I emailed both JE and Wiseco and the only response I got was from Wiseco so I figured I would go with them.... We paid for them them the first or second week of December, so I thought we would have everything put together relatively soon after that.

I have tried keeping my emails and messages relatively nice, but I can not have something like this putting me back that far. I'm getting really frustrated. Getting the turboed engine to run reliably is hard enough in one year and I would like to have a decent amount of time to be testing. The pistons may end up being the only thing holding me up. I will call the customer service desk on Monday and we'll see where it gets me.

Holiday season or not relatively decent customer service is pretty important. It's really not that hard to send an email letting someone know you don't have time to work on it right now.

[rjwoods77]

Biggy,

Sounds like a step up the food chain will help you. Seems like you have done all you could to avoid it.

[The Gus]

I'm very curious. What do you want from custom pistons? Since you're going turbo I assume lower compression. If so there are other, cheaper, easier, less permanent alternatives to lower compression - thicker head gasket jumps to my mind.

I know higher compression is available in their catalogue. Or maybe you want a smaller skirt? Or 2 rings instead of 3?

[Biggy72]

I'm planning on running at highest about 12-13 psi, I've got it calculated to 12.4, but who knows what it will end up being. I was hoping to drop the compression some and possibly give a little more clearance for the valves so I can play with the cam timing some. I thought about putting in a thicker head gasket, but how much of a drop could I possibly see? I'm hoping to get the compression ratio down to 11-1 or so if possible.

[The Gus]

As an alternative to custom pistons have you considered cutting the valve pockets deeper in the stock pistons to achieve both your goals? It's something you could do yourself on a milling machine - although you'll need to spend some setup time on it. Or you could even send your pistons to a specialty engine shop and have them do it (probably still a fraction of the cost compared to custom pistons). If you get/modify new pistons, are you planning to rebalance your crankshaft? Have you measured valve clearance with stock pistons, how much are you comfortable shifting your cams?

As for estimating compression ratio changes due to pockets or thicker head gasket, I suggest making a spreadsheet (in excel or other) to help calculate. Start by calculating combustion chamber volume and recalculate given the extra volume of the pockets or gasket. For a quick answer to your question, assuming the stock Honda gasket is 0.030"� (0.027"� compressed at 10% compression), you'll need a 0.044"� (0.040"� compressed) to get 10.98:1, given 12:1 base CR.

Since you've already ordered your parts this may just be unnecessary alternatives. Hopefully you get your parts soon. Goodluck.

George.

[Grant Mahler]

Stock pistons are cast with with a certain thickness for a variety of reasons. In the current race for horsepower between honda/suzuki/yamaha, I pretty much guarantee those piston crowns are as thin as possible. I for one don't want to be around when you run that motor on shaved pistons.

Also, for what it's worth, I've seen improperly made pistons from JE recently where the crown thickness varied wildly. The motor blew, and when we took out the pistons, the cylinder that blew had a crown thickness almost 2 mm less than the other 5 pistons (which also varied by ~0.5mm) ...

YMMV.

[Drew Price]

Isn't it reasonable to assume that the JE/Wiseco/Cosworth piston blanks for this size engine is common enough that the blanks would be forged, rather than cast, or wrought?

The stockers may or may not be, but I can think of way more factory pistons which are cast than are forged, even on high specific output engines.

Best,
Drew

[The Gus]

Stock pistons are cast with with a certain thickness for a variety of reasons. In the current race for horsepower between honda/suzuki/yamaha, I pretty much guarantee those piston crowns are as thin as possible. I for one don't want to be around when you run that motor on shaved pistons.

With all due respect, that is quite a weak argument in my opinion. It is analogous to "the motors are fully optimized in every possible dimension so no performance gains are possible". If that were true then there would never be newer and better motors because the manufacturers would have reached the limit. I should note the F4i is now 3 generations old.

I have a piston on my desk so I'm looking at it now. To lower compression you only need to pocket each valve maybe 0.020-0.040" (proper calculations are in order), - its really not that significant when looking at the piston. Although the safest thing to do is perform an FEA and see how much the stress rises due to the resulting thinner wall. Intuitively, I'm not concerned about 0.040"�.

[Grant Mahler]

I'm not saying the motors are fully optimized, obviously you are correct in that aspect. But I don't think you are going to be able to simply start cutting away material without going to a different manufacturing process, a different material, or some other means to strengthen the piston again. I do believe the engines are run near the edge of reliability for the materials they are made of and the methods they are produced. I don't think Honda made the piston an extra 0.040 thick, because they didn't want to shave it down or redesign it or whatever. The pistons are as thin and light as possible, within whatever design constraints they had. You will trade off something - heat transfer, long term reliability, squish geometry - something.

I don't have an F4i piston around, so I don't know how thick it is. The pistons I was referring to, which were custom dimensioned and built for the application by JE, were 4.5mm (.178") thick at the center. The failed piston was around 3.5mm thick (.138"). If I remember correctly, the motor was seeing 24lbs of boost from a GT35-76 turbo, spinning to 8200 rpm.

Personally, I don't care what you do with your motor. Shave em down all you want. I'm just providing an anecdote of my experience.

[Biggy72]

When Jeff was still emailing me back he had a concern with doing anything to a stock piston and then putting 12lbs of boost on it. With that said it seems like the pistons could have the raised area around the valve pockets to lower the cr. This doesn't give any more room for the valve, but it does solve the problem.

I personally don't feel comfortable machining on an already thin piston. We can't afford to screw around much with time and money so I just went the custom piston route. We are supposed to be getting the pistons for close to 40% off so it's not as bad as it could be. We also had the rest of the machining done for free and I would like to not have to have all of that work done twice.

[rjwoods77]

http://www.not2fast.com/turbo/compression/compression.shtml

Sort of part of the subject here but definitely a help for looking into things on your engine.

[Charlie]

Aren't there thicker head gaskets out there? Seems like a pretty simple backup solution.

I would agree that the factory pistons *might* have extra material, but then again, they might not. Not everything on a factory engine is optimized to the nth degree, but you really don't know what the limiting factors are. It's pretty risky in my opinion to remove material from a factory piston. If I was designing a piston from scratch, without any data to reference, I would take the factory piston, FEA it, and match those stress levels with my new piston (maybe even plus a small safety factor). Removing material and using factory pistons is the exact opposite approach, and really pretty reckless in my opinion.

[Pete M]

Head gaskets are a pretty crappy way to lower compression because they basically eliminate your squish, they are easy though. We did our initial turbo testing years ago with a head gasket that dropped our CR below 10. Do the math, it doesn't have to be that thick to have a big effect. We never went to a comp with that thing though.

Have you tried running the engine stock and seeing how much boost it will handle before it starts to detonate? Be careful, listen for detonation (with a det can, not with your ears), and you shouldn't damage anything, you just may not get your target boost. Also not ideal, but it's another backup plan. I know many teams run turbos with unmodified engines.

[overdrive535]

does the f4i have a knock sensor? (we run R6's)
I'm assuming it doesn't, but that could possibly be the easiest method to use for detecting detonation if it is equipped with one, assuming you know how to wire it.

Or I'm out in right field.

[Homemade WRX]

Originally posted by Charlie:
Aren't there thicker head gaskets out there? Seems like a pretty simple backup solution.

yeah but that also will mess with quench height/squish and cam timing...its a band aid but not ideal.

[JamesWolak]

JE provided us with some 11.X:1 ones back in 06. I would suggest calling them. They may have been custom but it might still be on file. They were for an F4i motor, i am from Lawrence Tech feel free to use those if you like they worked fine for us back then.

[Biggy72]

It's supposed to be moving forward now. I finally had to call his supervisor and the next day things were rolling again.

[IttyBitty]

I actually had a really easy time with Wiseco, but I didn't have them cut custom pistons.
I was running a turbo suzuki gsxr 600, and I called wiseco asking for the dimensions of their off the shelf piston. They gave me all the info I wanted on the phone, I ordered pistons, and I had them in about a week. I dropped the compression from 13 to 11, but I did it exactly the way Gus described. I stuck it on the mill...setup time was a pain, and I had a chart with the amount of material I took off and the compression ratio that amount of cut gave me. Once I achieved the compression I wanted, I cut the other 3 pistons according to my chart. This sounds tedious, I know, but my pistons only cost me $200 (with the 60% FSAE discount...and the extra 10% he threw in just to be nice) and I had no doubt about the pistons being safe, because I knew what the dimensions were from the getgo.

But hey, if they're moving on your pistons, then you don't need to go through all that stuff. I only did it because at the time, UC Berekely didn't have much money as a team and since the money came from my pretty little pocket, I decided to save money and invest time instead.

cheers!
Nika

GO BEARS!