Stock Block Sustained High RPM

[turbofabricator]

You can also drill and tap the rear corners or the cylinder heads for external oil return to the pan. I will do this on the next stageII build with TA heads, as they have less than adequate oil return provisions. (Especially with good oil control)

 

[CTX-SLPR]

Think doing the rear of the heads is sufficient? I was eyeballing my spare set of 8241's and it looked like you could put a 3/8in fitting between the exhaust ports up on the walls below the valve covers. Just thinking outloud on this one.

 

[turbodave231]

Great recommendation: Ken builds record setting Salt racing engines.

http://speeddemon.us/

 

[CTX-SLPR]

Can you actually talk to him and does he think in the "budget" realm? I guess I've always thought he was way out of my league to talk to about anything short of an open checkbook engine build.

 

[Reggie West]

Yes you can talk to him and he does understand a budget build.

 

[bishir]

I would like to discourage you because I would like to see you finish your Riviera first.

I enjoy the ECTA chat on Bangshift and would love to someday participate in their mile events since Bonneville is way too far for me . . . and I 'll watch this thread with interest.

 

[CTX-SLPR]

I would like to discourage you because I would like to see you finish your Riviera first.

I enjoy the ECTA chat on Bangshift and would love to someday participate in their mile events since Bonneville is way too far for me . . . and I 'll watch this thread with interest.

I'm still working on the Riv, just changed my goals and pulled back from the mission creap that had it starting to become very spread out over the protouring scene without a lot of the needed stuff. I'm going back to it being a nice cruiser with a good dash of engineering but nothing like I was thinking even a month ago.

I think I'm going short stroke, 181 motor since the records are slower and that saves me from a more expensive fire suit and I think I could build the engine stronger for the same price as a moderate attempt at a larger 231 or 252 motor. Got to wait for the taxman to return what he borrowed and paying back Christmas into the savings account though.

 

[CTX-SLPR]

Still SLOWLY working on this project as it's easier to plan than it is to work on a car when you have a 40min train ride twice a day.

Building a 3.0L destroker with a Molodex oddfire crank, forged H-beam rods, and BMS flat top pistons. I think that's solid for any RPM I want to run. The variables are how much do I need to do to the block and what approach do I want to take with the cam in regards to RPM. Do ya'll think a stock block can take 2min at WOT topping out at ~5000rpm on a 3000-5000rpm charge? Are caps/girdle needed?

Thanks,

 

[Hot Air]

I would think 5,000 rpm for 2 minutes would be doable. Oiling and balance of rotating parts would be critical. Dry sump? Also a stable valve train would be critical. Keep boost at mild level. Liberal ring end gap would also help. Good luck.

 

[CTX-SLPR]

I would think 5,000 rpm for 2 minutes would be doable. Oiling and balance of rotating parts would be critical. Dry sump? Also a stable valve train would be critical. Keep boost at mild level. Liberal ring end gap would also help. Good luck.

Wet sump with an enlarged sump and extra oil drains back into the pan. Block right now is one of those late 85 units with the 20bolt pan but cast valley and taller deck. I'd have preferred an earlier unit for a 14 bolt pan but standard bore is getting harder to find.

Need ~350hp at the crank at 5000rpm to run the number, I bet I'll have to boost it hard to get that out of 181cid. 25in tire, 3.42 gear with a TH200-4R lockup should give me just over 150mph at 5000rpm and the aero data says I'll need 275hp at the wheels which I'm estimating at 350hp at the crank. Think of like a 3.8 linearly extrapolates to ~425hp at 5000rpm with the extra displacement.

 

[cruzn57]

another source of info on small motors .............
Don Wang, of DRW trans in Santee, Ca.
he runs a 224 cu in car and has gone 8.76@157 mph,
he is extremely user friendly.

 

[Hot Air]

Donnie is a super guy and is always willing and eager to share his knowledge.

 

[CTX-SLPR]

I'll have to get in touch with him this week to talk about the motor and what he thinks the block can take and for how long.

Playing with math (I love math!) and Borg Warner's MatchBot I came up with a turbo that gives me almost exactly the power curve I need to hit my aero requirements with ~10% to spare over a 20% driveline loss in 4th gear. Tops out at 18psi on the waste gate from ~3200 on, it's a $1800 turbo though which is probably 2x what I have in the rest of the hard parts of the engine.

I'll need to do more math with a modeling program I wrote in excel to plot stuff on top of turbo maps to check it out. Can't do what the MatchBot does with the phi curves for the turbine but it'll get close I think.

 

[MCH86GN]

Very interesting. I tried to find out the max speed in GN and ended up breaking the rocker shaft and that in turn unseated a lifter bore and I lost most of my oil pressure. Stupidity is expensive.

 

[CTX-SLPR]

Interesting that this came back up today. Just was talking with someone that was working on the Buick Indy program (and has run 300+ at Bonneville) who thinks that the stock block will be solid at 6000rpm with a good rotating assembly so that pushes the limits back up a notch for sure. One thing that I'm not sure has been given much thought is the fact that I'm running an Oddfire crank and the uneven firing sequence I'm sure has some effect on the block's durability under sustained power.

 

[turbofabricator]

Call Kenny Dutweiler. He will be able to answer all your questions about building an odd fire V6. He's made 1900+HP with one. You would be way ahead letting him source everything you need. Experience TRUMPS mathematical equations. I work in aviation and many times math has failed us. Use math to try and explain what works.

 

[MCH86GN]

Call Kenny Dutweiler. He will be able to answer all your questions about building an odd fire V6. He's made 1900+HP with one. You would be way ahead letting him source everything you need. Experience TRUMPS mathematical equations. I work in aviation and many times math has failed us. Use math to try and explain what works.

Most mathematical equations are for ideal conditions.