DSS Pistons?

[Rory428]

I have the 428 from my 59 torn down, it is standard bore, cylinders are still standard bore, measure straight, but have shadows at the top from ring ridge. Anyhow, figure that it`s time to bore it, and a buddy that did my machine work back when I lived in BC, has been using pistons from DSS, and he likes them. This is mainly a street cruiser, that sees the dragstrip once or twice a year, on pump gas, (91 is the highest octane available here), so I want to drop the compression a little, hopefully 9 1/2- 10.0-1, and DSS shows a .018" dish, plus valve notches, their chart shows 10.20-1 with a 65cc chamber, and 9.54 with a 72 cc chamber, so they should be pretty close with my TFS heads.  They have a 1/16"/1/16"/3/16" ring set, just wondering if anybody has any experience with DSS ? Also, they offer these pistons in 2 alloys, 4032 or 5023, not sure which would be preferable for my application, which has a mild solid flat tappet cam, and will likely never see 6000 RPM. Thanks.

[1968galaxie]

I was looking at those DSS pistons as well.
4032 alloy and 2618.
The 4032 are low expansion type - requiring less clearance.
I had a note from DSS telling me the 4032 was a better choice for endurance street build.
Hopefully someone with experience using DSS pistons will chime in.
I liked that they had +0.040" sizes available.
Pricing looks decent as well.

[blykins]

A 4032 is generally best for a naturally aspirated street engine because the piston/cylinder clearances are tighter at around .003-.0035". 

The DSS stuff uses what is now getting to be an antiquated piston ring size.   You really don't see 1/16" rings anymore as most aftermarket stuff (even for FE) has gone to at least 1.5/1.5/3mm if not 1mm/1mm/2mm. 

I would personally look at a Racetec piston.  If you go through one of us on here that deals direct with them, the pricing will be favorable and we can even do custom bore sizes so that you don't have to bore a block to the next size up.  If you just have shadows in a cylinder wall, cylinders aren't perfectly round anymore, etc., then something like that will usually clean up in about .005" instead of going to a .030" over, .040", etc.

[machoneman]

Well, FWIW, I have DSS .030 pistons but in my 351 Windsor engine now since 1994, first run in early 1995. On a head upgrade in Fall of 2020 and after approx. 13K miles, the pistons and rings looked great and leaked down just a tad. You'll find the folks speak Ford like no one else in the greater Chicagoland area and surrounding counties. Former Pro Stock runners, they grew to be a big player in the stroker kit, piston and head arenas as the 5.0 crowd took off in the late 80's, 90's and 2000's. And yes, they did and still do FE's and BBF's. I recommend them as great folks to deal with. They still use the older 1/16 rings though.

[frnkeore]

This is a CR program, by Diamond. CR could be off slightly(like +- .05), depending on top ring ht (I used .280)  I used a Mr. Gasket 5790G .038 x 4.400 Graphite 9.47cc, head gasket, for a slightly better Quench. The CR is 9.62 with a 1020 gasket.

DSS does have optional rings 1.5, 1.2 & .043 (no low tension) for $309 when order with pistons. .040 is the only std OS and it's $80 for others. Total price $1069 + shipping.

The thing that I saw in the pictures, that I don't like is the snap rings for the WP's and I didn't see a option for that.

Last yr, I bought a set of totally custom 2618, Ross pistons, including low tension 1.5mm rings for $1063 shipped through Probe Indust.

With the custon set, you can get your pistons up higher in the block, for a much better quench.

[FERoadster]

Rory:  I bought a set of RaceTec's from Brent within the past year off a dyno build. +030 with new rings. My 428 block is already + .030 and thought I'd use them. I paid around $500 + shipping (USD) - (Pistons and Rings). Might consider selling them since I might sell the engine. Not planning to make much of a profit since rebuilding the shortblock can be costly and I could avoid the expense.
Not really anxious to sell but, I could use the money and sell the 428 as well.  The 428 has very few miles since the rebuild. Pulled it running from a 1974 F350 dually fellow was putting a 460 into. Figured I'd just put the pistons in with a slight hone and hope for the best.
Getting ready to downsize the numerous FE blocks I have.
Richard >>> Roadster

Correction: Checked the pistons and they are AutoTec A4123F, Rings still in the box are Total Seal 1/16 1/16 3/32. Includes circlips.
See Brent's post in Vendors Classified about the pistons. (Jan. 2022)

[1968galaxie]

A side note:

1/16" rings are 0.0625" thick,  1.50mm are 0.059055" thick - a huge difference of 0.0034"

I do like the 1.2 or 1.0mm rings - if available, but nothing wrong with 1/16" ring in a daily driver.

[blykins]

A side note:

1/16" rings are 0.0625" thick,  1.50mm are 0.059055" thick - a huge difference of 0.0034"

I do like the 1.2 or 1.0mm rings - if available, but nothing wrong with 1/16" ring in a daily driver.

It’s not just the top or 2nd ring, a 3/16” oil ring pack thickness is huge compared to the 3mm ring pack.  It also sheds a lot of weight.

[winr1]

Not putting down smaller rings.. but for a street build what are yall seeing ??

Do the smaller rings wear the block less ??


Ricky.

[blykins]

Not putting down smaller rings.. but for a street build what are yall seeing ??

Do the smaller rings wear the block less ??


Ricky.

Less friction, more horsepower.  It's evident when you knock a piston/rod assembly down in the cylinder, so much less effort.   On my big bore FE's, I'm seeing 8 lb-ft of torque to roll the rotating assembly over (all the pistons/rings, cam, etc.) with a metric ring pack. 

There are no downsides to the thinner rings, even for a low-effort street build.

[My427stang]

I will echo what Brent says, no downsides in practice and none in research before started to use them.

The difference is dramatic, starting when you put the rings on the pistons, they go easy, and when using a tapered compressor, you give them a light shove with your thumbs and 1mm/2mm combos  almost carry themselves down the hole. 1.5/3.0 packs are not that much different.  I am finishing a 462 right now with 1/16 rings, it'll make power and nothing wrong with it, I did those with the same compressor and they went fine, but the difference is significant.

It's not ring design either because I have used Hastings and Mahle in all three sizes and it's consistent regardless of ring.  FWIW I have only used std tension oil on all. As far as wear being better, research says yes, but I haven't had one apart. 

As far as DSS, haven't used them, but I would assume better than a Speedpro, I'd look at clip design, pin weight,overall weight, then start measuring and see how consistent dimensions are, but I also think Racetec with a 1.5/3.0 or a 1.0/2.0 is hard to beat, and if Mahle has shelf pistons, also a very good deal for what you get.  I wouldn't mine seeing what someone finds though, if the price is right and it's a good piston, always good to have options

Back to the rings, one bit of advice, I tried many years ago to use my old favorite wrinkle band compressor with a thin ring, don't do it.  Buy a 40 dollar tapered.  I also have a nice set of Snap-on plier-type with multiple interchangeable bands, it'll work with the thin rings, but the tapered compressors are where it's at.  The old two thumb shove and it's in

[Rory428]

Ross, I looked into Mahle pistons, but the majority of their FE pistons seem to be for  stroker applications.  All their 428 pistons are for at least a 4.250" stroke, and the only pistons that I found, for use with a 3.98" stroke, were for a 390 bore.
As for Sealed Power/Speed Pro, it seems that all their pistons are made off shore now, mainly India, and I was talking to my old machinist buddy that did my machine work when I lived on the West coast, he said he recently built a 383 MoPar, and it took 3 sets of SP pistons to come up with 8 usable pistons. The sizes were all over the map, as was the weights. That is such a shame, I had used both the 2303 CJ replacement, and 7024P domed pistons in my 428s over many years, and never had any issues.
Richard, I will let you know about the AutoTecs, but at the moment, it appears the compression ratio may be too high for the TFS heads, and the 91 pump gas we have here.

[Barry_R]

The metric rings usually have a reduced radial wall thickness as well - allowing them to be more conformable to the bore. 
Just better parts.

The Mahle rings are better than the Hastings rings - sometimes you don't have a choice.

DSS has been making pistons for quite a while - since the old 5.0 Mustang era.
They used to use blanks from the TRW Clarkwood plant - not sure who supplies them now, but that are really only a few sources.

The 4032 alloy has silicon, which makes for a more durable product - longer life for ring grooves and skirts.
The 2618 alloy has better high temperature characteristics
There is enough overlap in low usage Hot Rod applications that it may not really matter much.