Engine Calculation Spreadsheet

"Sweet Trav" (thespunbearing) 12/10/2014 at 14:39 • Filed to: None

2

32

For all you engine nerds like me.

Here's a spreadsheet I use

https://docs.google.com/spreadsheets/d…

RamblinRover Luxury-Yacht > Sweet Trav 12/10/2014 at 14:49

0

Nice.

Sweet Trav > RamblinRover Luxury-Yacht 12/10/2014 at 14:51

0

its funny because i just wrote a post on how i cant do math, excel on the other hand lol

RamblinRover Luxury-Yacht > Sweet Trav 12/10/2014 at 14:57

0

I already did most of this math by hand for the Rover V8 in the course of figuring out what conrods I needed, but other than the conrod length, I pretty much forgot everything lol

HammerheadFistpunch > Sweet Trav 12/10/2014 at 15:02

0

BLESS YOU! I've been meaning to do this.

Sweet Trav > HammerheadFistpunch 12/10/2014 at 15:21

0

it actually works now lol. i copied from excel and it was just values lol

yamahog > Sweet Trav 12/10/2014 at 15:24

0

Weird, I'm not seeing anything about turbine blade angles.

Sweet Trav > yamahog 12/10/2014 at 15:25

0

I'm talking about pure blooded 'merican engines none of that German designed turbine crap

yamahog > Sweet Trav 12/10/2014 at 15:31

1

I'm talking Mach 3 in the air crap :P

Sweet Trav > RamblinRover Luxury-Yacht 12/10/2014 at 16:21

0

5.66

RamblinRover Luxury-Yacht > Sweet Trav 12/10/2014 at 16:29

0

I'm doing something wacky with an odd crank, so they'll actually be 6" rods. 4.2 crank has a longer stroke than the earlier ones, but used similar rods - I want to use 4.0 pistons, which are much shorter, so the rod length ends up being an intermediate size. 4.6 rods would be too short (and too big on the crank end), 4.0 rods would be too long (and ditto), 6" rods end up being just right - and the right journal size when ordered for an SBC with an offset grind.

Sweet Trav > RamblinRover Luxury-Yacht 12/10/2014 at 16:34

0

doing the Buick 300 crank swap?

RamblinRover Luxury-Yacht > Sweet Trav 12/10/2014 at 16:45

1

Nope, keeping the 4.2 (261) Rover crank I've got, but it's a crank that nobody builds competition pistons/rods for because they didn't make that many. It was supposed to be a diesel that never got made, so it's the odd man out intermediate size they only went through one tooling set on. Particularly since it got introduced just in time for an engine style change and would have needed rework to make a proper sibling of the 4.0 and 4.6 - just not something they wanted to do.

The 300 is fun and all, but it's not a huge size improvement on the 4.6, and it runs into the same issue that the 4.6 does in that the heads have an upper limit on how much air they can move. Full-blown competition heads are available, but that's beyond anything I need to be doing - for a light vehicle I'd just as well rev a tad higher on a tad less displacement. More than the 4.0, less than the 4.6 - heftier crank, improved crank bearing bolting (but smaller bearing), improved oil flow with smaller/less greedy rod bearings that can be fit a little better, and no dependence on the later engine style full dizzy replacement GEMS EM/EFI system. Basically, I'm trying to build a hybrid engine that has most of the best of everything, and having the 4.2 late intermediate gave me most of what I wanted. Crossbolt style block, better oil pump, better heads, timing cover with dizzy drive, a less failure prone liner setup than most, and a pretty bulletproof crank right in the sweet spot for size.

roflcopter > Sweet Trav 12/10/2014 at 17:18

0

Now make one for rotaries... I've got all the formulas laying around here somewhere.

Sweet Trav > roflcopter 12/10/2014 at 18:38

0

The rotary sheet is just a step by step LS swap instruction guide.

#rotariesaregarbage

roflcopter > Sweet Trav 12/10/2014 at 18:43

0

Flynt Flossy has a message for you.

AMGtech - now with more recalls! > RamblinRover Luxury-Yacht 12/10/2014 at 23:23

0

Iceberg!

Merlin F85!

Did you get a block that was new enough to already be cross-bolted or one that only had the bosses still needing to be drilled? What are you using for a cam? I would grab a die grinder and go to town on those heads. Also, bigger valves are quite nice. What about head gaskets? I recommend Cometic with studs, I have yet for that set up to leak again as long as head and deck were both fresh surfaces.

RamblinRover Luxury-Yacht > AMGtech - now with more recalls! 12/11/2014 at 09:07

0

Damn right I've got an iceberg crank. With early A36 block, so it needs the bosses drilled (but it has them). Haven't decided on a cam yet - I got some recommendations from Dan LeGrou at D&D Specialties and may end up with one from The Wedge Shop. They *are* the newer heads, so about the largest practical valves for the stock head - I've got a specialty book on the engine that includes a max safe porting profile. I've definitely going with the ARB head studs, because the alternative is really foolish.

AMGtech - now with more recalls! > RamblinRover Luxury-Yacht 12/11/2014 at 09:33

0

At least if you go too far porting it replacement heads are easy to find for not a ton of money. I've had SBC valves installed before, works quite nicely. So by newer heads heads do you mean the 10-bolt version? Those are much better than the 14's.

RamblinRover Luxury-Yacht > AMGtech - now with more recalls! 12/11/2014 at 09:36

0

Yep, ten-bolters with waisted valve, designed for a composite gasket instead of tin (smaller dome).

AMGtech - now with more recalls! > RamblinRover Luxury-Yacht 12/11/2014 at 09:43

0

Nice. I've blueprinted and built a few of these years back. I've mostly gotten out of Rovers because they're a giant pain in the ass and not really worth the time and money to make them better, but I kind of love then anyways. I've re-lined, bored to SBC, offset ground cranks for extra stroke, full head work, blah blah blah. Currently I'm kind of sort of reluctantly consulting on a 4.6 build for a D90 with 14cux EFI.

RamblinRover Luxury-Yacht > AMGtech - now with more recalls! 12/11/2014 at 10:06

1

There does seem to be a "you don't have to be crazy to performance build these, but it helps" thing going on with Rovers, certainly. In my case, it ticks all the correct boxes - loosely period correct for my project, simple to build, light, smallish displacement, V8, and cheap to get started on, if not to complete. Lower output per liter than a well built SBC, some expensive aspects, tinkering required to optimize, and pitfalls for reliability, IDGAF. Also, because putting a British engine of any kind in an American truck is so delightfully wrong.

RamblinRover Luxury-Yacht > AMGtech - now with more recalls! 12/11/2014 at 10:18

0

I should also note that the Rover has a "well, nobody else is doing this" freak factor that makes it attractive. Kind of a

sort of thing. Also, since I'm putting it *in* the firewall, a front-mount dizzy, oil pump, and filter are all good things.

4.6 D90 with CUX? What did he do, swap to an intermediate timing cover and cam setup and recut the crank keyway?

AMGtech - now with more recalls! > RamblinRover Luxury-Yacht 12/11/2014 at 12:02

0

Those are the same things that made them attractive to me. Except we were still putting them in Rovers. But I love the idea of putting one in an American truck.

You are exactly right with how it is set up. We've got an excellent machine shop that has no issues modifying or improving anything so it's not a real big deal.

RamblinRover Luxury-Yacht > AMGtech - now with more recalls! 12/11/2014 at 12:14

0

I will definitely remember to keep you on file in case any huge I-have-no-idea-what-I'm-doings crop up. I've been present for engine rebuilds before, but this'll be the first time properly speaking for both me personally doing a full top to bottom every-piece rework, and the first time doing a performancey build. I know how it's done, I've seen it done, I've helped it get done, and done large parts of it, but never everything all together on me.

The local machine shop (the one I'll probably use to get my cam bearings right and my flywheel redrilled) coincidentally had the guy start seriously looking into rebuilding a Rover for something, and shortly after he got into it he had a "haha fuck that noise" moment with what he had. I don't know if it's because he was trying to rework a 3.9 with bad liners or what - that's all I know.

Sweet Trav > RamblinRover Luxury-Yacht 12/11/2014 at 13:20

0

biggest problem i see with the Rover V8 on paper is that small bore. can you make it a bit bigger with new cylinder liners?

I know almost nothing about that engine except it started out life as a buick engine.

RamblinRover Luxury-Yacht > Sweet Trav 12/11/2014 at 13:42

0

It started out as a 215CI Buick/Olds/Pontiac. The Rover heads are based on the Buick version.

Mine is the bigger of the two bores out there, 3.70. The cylinder block only has the room for a little over an eighth in extra diameter before you're into the water jacket - so while you can have them bored out to big enough to reline at SBC smallest diameter (3.875), much more beyond that and you'd have to rework with a wet liner system. That would be way more trouble than it's worth, so the usual approach is to go as big as you can comfortably and go for a big stroke and better heads. Highly optimized race builds on the block tend to have maybe a 3.8-ish bore, but a crank (carefully set up to miss the cam - they're that close) pushing it up to something like 5.5l at the absolute top end (I don't have the book with me at the moment). The head design is kind of a limiting factor anyway - a simple bore size increase wouldn't help enormously other than down low.

Playing with the liners is sketchy in some respects anyway as the blocks vary somewhat in thickness around the liner, and the original liner design (press in, open to top) can develop corrosion between the liner and the aluminum which then goes sideways into the water jacket. Generally if you need liners, you just overbore slightly and install a "top hat" liner that gets held under tension by the head and seals to it completely - much better. It's nothing like as easy as increasing the liner/sleeve size for a Jag V12.

Sweet Trav > RamblinRover Luxury-Yacht 12/11/2014 at 13:44

0

What advantage is there over say installing an LS motor?

Doesn't seem like an optimum starting point, the small bore is like building a 305 small block Chevy.

RamblinRover Luxury-Yacht > Sweet Trav 12/11/2014 at 14:19

0

There are two paths forward, there: classic SBC or SBF for that matter is just too damn heavy. As much as a Rover V8 is usually shackled with a heavy flywheel that negates some of this, and induction system and cranks hurt this more than they should, the RV8 is stupidly light for a V8. The base engine, shaving off excess weight, is in the same class as the lightest LSes and lighter than pretty much everything Ford V8 short of the aluminum bore Coyote.

If one is making an LS (the other patch), one is starting with an engineered solution, to be sure, but to "score an LS for free" as detailed in the article, you have to do a lot of shopping to get one along the lines of what I would want. The aluminum lower-displacement LS engine, were I to get one (harder than a base Rover), I would then need to set up with a full GM-approved ECM setup or flounder around trying to bodge something. I don't, repeat *do not* want a fully modern-looking or modern set up engine in the project, and unless I do something goofy, the LS is further from my target in that respect. IMHO it looks cheesy, and I want a dizzy on the stupid engine. Then there's the flow direction foolishness. Further, when somebody puts an LS in a project, they're mostly trying to pick the right base engine from many variants, and not building to suit. Building to suit has a lot of appeal.

The bottom line is this: I want an engine with a lot of the advantages a classic SBC has over an LS -broadly simpler, much wider ability to build *as I want*, etc. without the weight and *with* some other features I like. It's an engine with flaws, to be sure, but those flaws are documented over decades and addressable. There are Megasquirt profiles on file for it, and even somebody making manifolds to use my preferred motorcycle throttle bodies - I'm being unique without having to break that much new ground.

Back on the mechanical side - with the big fat heads, the engine isn't really physically much smaller than an SBF. A broadly "bigger" engine wouldn't be hard to do, and has been done. *But*... I don't want displacement uber alles. I just want final NA hp. Displacement is easier than revs, but you can build one of these to respectable redline, and I want to have a car that's functional in day-to-day use - better than idiot level fuel economy. Combine with the fact that I'm more inspired by F1 and Indy V8s of the 60s-70s (particularly Mickey Thompson's Buick block indy car and the Cossie DFV), and "MAKE YER BORES BIG BRAH" has less than no appeal to me. Stacks + small to low displacement + revs - > LS? Nah, bro. Going torque-happy beyond what's there even makes the drivetrain harder to engineer. Could I still do this with a low-displacement LS? Somewhat, but I'd be more constrained and have less fun.

On the weight front: Weight is critical. I'm dealing with a platform that was a touch nose-heavy with a six, and I want more than just straight-line performance. You can't imagine the appeal of actually *reducing* the vehicle's weight problems with a V8 swap. Overall nimbleness is my aim, not tire smoke. Think Cortina, not big-block Mustang.

Sweet Trav > RamblinRover Luxury-Yacht 12/11/2014 at 14:35

0

I want to either De-stroke a 6.0 LS with a 4.8l crank (perhaps a 3 inch custom crank) or build an old 302DZ copycat with a 327 block and a 283 crank and four t. an LS7 destroked with a 4.8l crank would be fun as well. There are a bunch of way to actually run a distributor with an LSX if you want.

Yes I can appreciate reducing the vehicle's weight with an LS swap, as the Monte had an all iron V8 from the factory. I can also appreciate building something to suit.

Big bore, short stroke with a long rod is what you want if you want to rev. examples being the 302DZ and 302 Boss engines. I want 8500-9000 RPM out of a pushrod motor.

RamblinRover Luxury-Yacht > Sweet Trav 12/11/2014 at 14:57

1

I'm fine with 6500-7000, basically, and the Rover is a simple, clean "classic" style way to do it. I want to rev, but 3.03"... this is not a huge stroke (.03 longer than the Boss 302) and really should be fine with a 3.7 bore. The 4.0 is even shorter (2.8") but that's really starting to push it. Somewhat smaller engines can rev too, after all. My current plan is to use a very short piston indeed (from a 4.0) with a very long rod (6") and that stroke - I should be *fine* for revs with a pushrod and valve spring upgrade with the cam.

I want revs+only moderate displacement, so trying to figure out which Tahoe or F-body I wanted to cannibalize for which permutation of the LS1, and getting, say, an L99 crank and then doing a whole bunch of fiddly stuff to put all that together and ending up with an engine I didn't really care too much for in the first place...

Getting to something that looks like this (with rails not webers):

is easier and more practical in quite a few ways for my project than getting to something that looks like this:

...and better suits the nature of the car. If I'm going to be doing fiddly, it might as well be fiddly that I like. Oh, and I do have the old style fluted valve covers, obviously.

AMGtech - now with more recalls! > RamblinRover Luxury-Yacht 12/11/2014 at 22:52

0

That's cool. Sounds like you've got a pretty good idea what to do, these engines are easy to put together. They mess themselves up more than you probably will.

RamblinRover Luxury-Yacht > AMGtech - now with more recalls! 12/12/2014 at 09:35

1

Let's just say there's a reason that I'm designing toward a pretty easy engine pull.