Engine Studs, Heres what I see on the Mkt & What do you run?
08-21-13, 09:01 AM
#26
This is completely accurate. Nothing will stop an engine from breaking under heavy detonation, or pre-ignition. It wouldn't matter if the block was a solid billet piece, etc etc. Tuning and fuel used is by far the most important piece to preventing an engine from breaking. I have two customers making over 950rwhp using just our stock "sized" stud kit. Their engines will not last one quarter mile pass without our kit( one blew 7 engines in one year to figure this out). The most important thing our stud kit does it stop the engine from expanding. The stock tension bolts allow the engine to expand a few thousands, and our studs allow zero expansion. This was measured on an engine dyno using a strain gauge. On a side note our kits are the only ones that have an allen head embossed into the tip, making installation easier, and our kit fits the OEM flywheels.
08-21-13, 09:17 AM
#27
also agree, there is no safest way to do it for an engine that has a tuning issue or anything feeding the engine that is having difficulties like ignition break up or fuel drop-off. if the engine doesn't break from twisting it will warp/break the seals, fracture corner seals or dent the thinner/lighter late series rotors.
i prefer milled tension bolts personally, to fit the block snug and not only add additional clamping force but also aid in blocking the ability of the irons to move from the housings due to bore differences between the two.
i prefer milled tension bolts personally, to fit the block snug and not only add additional clamping force but also aid in blocking the ability of the irons to move from the housings due to bore differences between the two.
08-22-13, 08:46 AM
#30
I could see how to clamp all but the rear Iron for a girdel by using PS mount bolt, emmisions rack bolts and EGR flat plate on center. Maybe use the spot where the thin cover plate gets bolted on? then again those are only 12mm bolts. On the other side of the engine is that large piece of material... intake manifold. I have only seen scrub marks or movement signs on the combustion side so the intake side must have enough to keep it in place.
I think BDC helped make it a bit better by using the entire Dowel pin land on the rear iron (drilled deeper, small dowel spacer in the center iron to make use of more surface).
I think BDC helped make it a bit better by using the entire Dowel pin land on the rear iron (drilled deeper, small dowel spacer in the center iron to make use of more surface).
08-22-13, 12:40 PM
#32
Old [Sch|F]ool
The FC had the mounts moved to the center because the rack and pinion steering precluded the ability to use the front mount.
The FD had the mounts moved to the rear so that the drivetrain would be balanced on the engine mounts, since FDs do not have transmission mounts, just the PPF.
08-22-13, 08:42 PM
#37
08-23-13, 02:59 PM
#43
Just illustrating the idea. A girdle is used to clamp something together. Imagine turning that engine on it's side. Clamping the combustion side of the rotary engine together just like the engine above has the head clamped on. In this way you could relieve the stress from the dowel areas.
08-23-13, 03:05 PM
#44
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the R26B has a big CF stiffener on the top of the engine, and the dry sump plate looks fairly thick too
08-26-13, 12:30 PM
#48
i have seen engines laugh at 1/2" and thicker plates of aluminum on the bottom deck. about the best i can envision is high tensile steel 4240 in a 1/2" thick or thicker deck plate with oversize mount studs would probably work but it would require sumping the oil system unless you could baffle the plate for the oil pan(plasma/water jet the holes for regulator/bypass and pickup tube, ideally the plate would have to be solid though otherwise this could be an effort of futility), this would still require the engine to be removed and the pan bolt holes reamed larger and steel thread inserts installed into the rotor housings.
thing to remember is the irons are not trying to move away from the rotating assembly but the rotor housings are trying to twist away from the combustion forces, and the rotor housings have almost no way of supporting themselves via an outside brace system. aluminum is also a soft and easy to move material so even the decking brace system may not work, although it would definitely help, but so do the following systems.
1)the easiest way is larger tension bolts without reaming the block, for more clamping force. not ideal but it is better than the factory tension bolts/dowels alone.
2)the more difficult but better way is to ream the tension bolts for snug fit tension rods which will not allow the engine to twist against itself, since the tension bolts act as 16 induvidual dowels plus the factory 2. can that really be argued against? technically you do not need to ream all 16(or 18) but i usually do 6 oversize tension rods.
3)about the same as above is adding more dowels, but dowels are hollow and i have seen them still warp/crack and also still allow irons to crack. ideally additional dowels would be solid but the only place you can use solid dowels is in the factory locations due to tension bolts passing through the rest. this also means external oil plumbing to the front/rear iron.
i have to think about these things quite a bit and i simply can't foresee a simple bolt on fix. some things you simply can't upgrade without internal machine work, such as 2 bolt main SBCs and making any real power with them. thicker dowel bossed cast irons has always been the best workaround, but the early engines did not have the luxury. nor was it a fix for extreme conditions. rotor housings could add additional threaded bosses but where? the casting simply won't allow for it aside from the top of the housings but this also wouldn't work for some setups with space limitations under the UIM.
Last edited by RotaryEvolution; 08-26-13 at 01:00 PM.
10-30-13, 01:46 PM
#49
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