Where to you locate an alternate engine?

[TomL]

I have a question that I don't see addressed in the ST rules and I don't recall having been discussed in the forum. If you install an alternate engine, where can it be located in the engine compartment? Other than the paragraph in STO regarding engine setbacks for certain engines, it's addressed in only one place that I see - the allowance for FWD engines in RWD cars to locate the long block anywhere in the engine compartment, plus allowing firewall modifications to clear accessories.

But for all other engine swaps - nothing at all. So, if I swap one RWD engine for another, where can I put it? I can see at least two interpretations - 1) The "Roffe corollary" version - if you can swap engines, you can bloody well swap engines, i.e., put it any where it will fit. All engine swaps allow this and the FWD-to-RWD language above is just an additional allowance to also modify the firewall to clear FWD-oriented accessories. 2) There's nothing allowing you to move the engine, so it has to be in the stock location. But with a non-stock engine, what is "stock location"? The two normal definitions of stock location relate to either number one plug location or bellhousing/engine interface location. But with a non stock engine and/or transmission, what do these mean? If you swap a six into a four cylinder only car or vice versa, the distance from no. 1 plug to interface is different (and on a four to straight six swap, by maybe six inches). Do you move the engine to keep stock trans location, move the trans to keep the no.1 plug location, or what? And once you add an aftermarket trans, then what?

I seem to recall that at one time there was language requiring "stock location", but it's not there now (if it ever was). My reading would go with the first interpretation, because the "stock location" reading would need to have a definition of "stock location" to make any sense, for the reasons noted. If stock location was intended, I assume that the rule writers would have addressed what stock location means for non-stock parts. But I know what trouble assuming will get you into.

The only problem I can see with the liberal reading is that it would allow engine swappers to move their engines back as far as possible, while cars with stock engine and trans have no basis in the rules for doing so, and thus couldn't move theirs back at all. On the other hand, the rules already specifically allow maximum setback for FWD-to-RWD engine swaps. Why should they be the only ones to get that advantage over all other engine swaps?

So could someone enlighten me as what the rules are intended to say?

 

[Greg Amy]

If you install an alternate engine, where can it be located in the engine compartment?

It's an item on the committee's agenda. Feel free to offer debate/discussions/suggestions here.

GA

 

[TomL]

Well, Ill put in a vote for allowing the same rule for all engine swaps as you have already allowed for FWD-to-RWD swaps, except maybe for the "modify the firewall" allowance. If you're going to allow "latitude" in engine swaps, as discussed in the Intent section, you have to include some specific parameters. Otherwise, it all comes down to each individual's opinion of what is reasonable.

With the large number of variations that are possible with the allowed engines, there is no way that a "stock location" based rule (however defined) is going to cover all the possible engine swaps, or at least not without resulting in some unworkable engine positioning (e.g., 4-to-straight 6 swaps, or vice versa). Allowing "anything that fits in the unmodified engine compartment" is easily defined and enforceable. Plus it give maximum flexibility for fitting unusual combinations. And since you've already allowed it for FWD-to-RWD swaps, I see no rational basis for not also allowing it for all engine swaps.

Since this would usually allow swapped engines to sit further back that than the location of the stock engine, the remaining issue is whether stock engines should also be allowed to take advantage of the "anywhere in the engine compartment" language. I have no opinion on that - it's a form of rules creep to allow it, but a disadvantage stock engines to not allow it.

In addition to the fore-aft location issue, what is the rule going to be on engine height? Same problem as with fore-aft - the presumption is stock height, but with engine swaps, what does that mean? Again, I don't see a good solution for engine swaps other than "whatever fits". However, I think that allowing free heights for stock engines could be a serious rule creep issue. With dry sumps allowed, and free engine height, it may effectively require (expensive) dry sumps solely for the purpose of reducing CG height. It depends on how much you could drop the engine due to bell housing clearance, but if you could drop your engine three inches by going to a dry sump, would you feel the need to do so?

 

[Z3_GoCar]

Excellant point Tom. Let me interject with my swapped motor experience. My alternate motor accomplishes two things, it gets me a better intake manifold that didn't come with the generation of motors in the Z3. Also, I get a smaller motor so we don't have to weigh over 3k lbs. My alternate motor has the same bosses and transmission as my current motor, so it sits in exactly the same spot as the stock motor, bolted to the original ZF transmission when that motor came with a weaker Getrag from the factory. If I were to swap in a four cylinder, I'd place the motor in the exact same spot the four cylinder motors sat in the four cylinder version, and it too could be bolted to a ZF transmission.

 

[Matt93SE]

In addition to the fore-aft location issue, what is the rule going to be on engine height? Same problem as with fore-aft - the presumption is stock height, but with engine swaps, what does that mean? Again, I don't see a good solution for engine swaps other than "whatever fits". However, I think that allowing free heights for stock engines could be a serious rule creep issue. With dry sumps allowed, and free engine height, it may effectively require (expensive) dry sumps solely for the purpose of reducing CG height. It depends on how much you could drop the engine due to bell housing clearance, but if you could drop your engine three inches by going to a dry sump, would you feel the need to do so?

I agree there's a conondrum here. how to put all these worms back into the can?

One thing to think about though is that we have to keep stock ring gear diameter. That's going to be the engine lowering limit for most any car I can think of, as my trans bellhousing is within an inch or so of the bottom of my oil pan.
Also, I can't drop the engine but maybe an inch without cutting the crossmember and removing/relocating the steering rack before the bottom of the block/crank weights start banging into stuff.

That may not be a problem in other cars, but it's certainly an issue in mine.

 

[Chip42]

this one one of the issues I raised in my omnibus letter a long while back (right around the time tGA joined the STAC). at the time, I don't think there was language allowing FWD wngine into RWD cars to be put "wherever" or however that language reads now, but there are some simple rules that would reign this mess in pretty easily.

1 - determine IF the intent of the rules allows (or should allow) for stock engines to be lowered, set back, or rotated about the crank centerline (especially applicable to FWD).

2 - require some specific measurements - 1:installed engine's stock angular orientation about the crank centerline (referencing Cyl #1 bore centerline vs vertical) and 2: for transverse applications: installed engine's crank/bellhousing interface plane position relative to vehicle centerline as delivered in the doner car.

3 - as the baseline, use stock or installed engine's angular orientation and stock bellhousing interface position from vehicle centerline, or the chassis' stock bellhousing plane for any installed engine (stock or swap) in longitudinal applications.

based on the answer to the above questions, set the limits/tolerances from stock. allow or disallow certain modifications, such as cross member modification / replecement as mentioned by Matt. this could make some chassis automatically better than others, so is worth considering with point 1. consider allowing transvere installations a greater angular orientation freedom in exhange for longitudinal setups getting a verical allowance as both will help driveline orientation.

pretty easy set of rules, just needs to be codified. cart's way ahead of the horse already.

 

[Greg Amy]

Some interesting thoughts, Chip. I'll have to go look up your old letter (you wouldn't know that number, would you?)

But as a scrutineer, I see a big hole in the logic: how do you determine "stock" location? Angular orientation? None of this is documented in the factory shop manuals. What's the chances of finding a stock example of whatever car you're inspecting at the time (and not risk it being a ringer brought in by the same team)? As a competitor, I'd have my $25 appeal form already pre-filled out the moment they start to do the "stock location" measurements. And I'm pretty sure the competitor would win.

I'm personally leaning toward the "within the engine compartment" or something along the same lines. The category already has a fairly large set of engine allowances, and something like that is far easier to scrutineer. But on the other hand, what could someone do such an open reg? Would anything they do be a significant change? If so, do we care? I'd really like to brainstorm the extremes of what could be done if given a big open hole like that to drive through.

Remember, any reg we create must be able to be objectively measured against a known standard, by person of reasonable - but not extreme - technical talent.

GA

 

[Chip42]

original angular orientation and the bellhousing plane can be part of the VTS requirements. for most engines this will be easy, as they are just revisions or other permutations of a engine series/family that WAS sold in the USA - M10/M40/M50/etc series BMWs, Nissan-VEs and -DETs, 20v and 1JZ toyotas, honda stuff (usually just differently stamped versions of what we already have here with slight differences that are already allowed or made irrelevant in ST rules), etc... when bolted into a chassis that accepted that engine family as stock, there is plenty of data to point to.

measure with the head off, as the car sits, referencing a cylinder wall. make the tolerance enough to allow for some rake in the chassis, and make it clear that the (seemingly large?)tolerance is there for that reason.

bellhousing centerline should be able to be reaosnably acertained from any body shop manual for the doner car. again, make it part of the classification requirements.

make a specific year range and model of car(s) part of the alternative engine allowance. so you can say (years) toyota Levin (AE110) "black top" 20V 4A-GE with 6 spd trans (C-something) has 5° slant and the bellhousing plane is 2
left of center. (those numbers are complete POOMA and used for example only)

BTW, are shift linkage / trans housing modifications legal to allow for swaps?

benefits to expliting these measurements are lower CG, both of the engine AND of the car as a whole allowing the chassis to be set lower without CV axle bind and better weight balance, including offset weight for a smaller drivetrain. there's liekly some actual but small power benefits as well from minimizing driveline misalignment at ride height, if not from less obvious things like creating better intake pathways and the like.

 

[Greg Amy]

I'm playing Devil's Advocate here, not intending to pick on you. I agree with what you're suggesting, but...

>>> original angular orientation and the bellhousing plane can be part of the VTS requirements.

There are no VTS for cars in Super Touring U and L. Anything can run in that class with the appropriate engine. And there won't be any VTS for engines except non-US market engines.

>>> make a specific year range and model of car(s) part of the alternative engine allowance.

Unfortunately, that's cat's long out of the bag, unlikely to be further restricted. But to do so would require a wholesale change in the philosophy, in addition to having to specifically approve each and every possible combination, immediately making any swap non-compliant until the STAC/CRB goes through the process of approving them. And given our slow lead times (request ->STAC ->CRB -> Fastrack) we'd be holding people up until we did.

It'll probably bite us in the ass eventually, but I just can't see moving from an "open" philosophy to a "permitted only".

>>> BTW, are shift linkage / trans housing modifications legal to allow for swaps?

Can't say for sure without specifics - and it's not really mine to say - but I would suggest it's compliant to change a car from cable to rod or hydraulic shift, if that's what the desired trans used.

>>> AND of the car as a whole allowing the chassis to be set lower without CV axle bind and better weight balance...

Note ST classes each have minimum ride height.

GA

 

[Ron Earp]

I'm personally leaning toward the "within the engine compartment" or something along the same lines. The category already has a fairly large set of engine allowances, and something like that is far easier to scrutineer. But on the other hand, what could someone do such an open reg? Would anything they do be a significant change? If so, do we care? I'd really like to brainstorm the extremes of what could be done if given a big open hole like that to drive through.

2. Engine and gearbox mounts may be solid, but must not relocate
the engine or transmission in any direction.

3. Either the OEM transmission or an alternate transmission must
be used; the alternate transmission must be from the same
manufacturer as the vehicle (e.g., an Acura transmission may be
installed in a Honda car). Alternate transmissions must be used in
their entirety. ​

What if the alternate transmission must move the engine somewhat from the "stock" location? What is the stock location if I'm putting an engine into a car that never had that engine in the first place, i.e., engine swap?

 

[Greg Amy]

What is the stock location if I'm putting an engine into a car that never had that engine in the first place, i.e., engine swap?

That's really the crux of the agenda item we're facing now: installing a rotary engine into a car that only had a piston engine (or vice versa). A reasonable person would say "well, that's a different story, do whatcha gotta do". But then a competitor will say, "well, if *he* can move the trans down lower without measurable restriction to accommodate that engine, why can't I do the same in my car that already *has* that engine..."?

Allowing alternate engines/trans comes with it a certain level of implied allowances. We need to figure out where that implication ends.

GA

 

[Ron Earp]

Allowing alternate engines/trans comes with it a certain level of implied allowances. We need to figure out where that implication ends.

GA

Let me know when you figure it out.

Ron "Considering a nasty Ford 2L with alternative transmission laid over about 50 degrees so it be much closer to the ground than hood" Earp

 

[Greg Amy]

Ron "Considering a nasty Ford 2L with alternative transmission laid over about 50 degrees so it be much closer to the ground than hood" Earp

But you see, that kinda stuff just doesn't bother me. If you want to spend all that time, money, investment, hassles to do that, I think ST is a great place for it. In the end you will have spent a tons of resources trying to develop it, you can't run dry sump in STL (and 2L engines are prob not competitive in STU where you can), your chassis still has to be 5" off the ground, you're going to weigh the same as other 2L engines (plus RWD 'cause I know you're a RWD guy), and...

...in the end all those resources and all that effort will result in very little performance benefit. Especially since you're probably going to put it in a damn Mustang chassis! And some guy in a Miata is still gonna wax your tail.

But if you want to do it, I say "keep a build log with photos, babe!"

 

[Matt93SE]

2. Engine and gearbox mounts may be solid, but must not relocate
the engine or transmission in any direction.

3. Either the OEM transmission or an alternate transmission must
be used; the alternate transmission must be from the same
manufacturer as the vehicle (e.g., an Acura transmission may be
installed in a Honda car). Alternate transmissions must be used in
their entirety. ​

What if the alternate transmission must move the engine somewhat from the "stock" location? What is the stock location if I'm putting an engine into a car that never had that engine in the first place, i.e., engine swap?

The problem with that is that the doors are already open in regards to trans. I can run a 6 spq sequential if I want. McClughan's Mazda 6 has an XTrac tranny with an external diff and that damn thing costs more than my car, truck, trailer, and all my spares combined! Of course it's mated to a Comptech engine too.


______________

Given all these relocation issues and blah blah blah, the old fully-built WC-TC cars all have every bit of that taken into account already. They also have gorgeous custom intake manifolds and airboxes (and restrictor plates to go with them)..

If you're going to open the door, why not just knock down the whole wall on that side of the barn?! :026:

 

[Ron Earp]

I'm dense but not dense enough to try and run a Ford Sn95 in a FWD Honda class. However, the thought is intriguing of what one could do with a 2L Miata and liberal application of the legal rules.

 

[Greg Amy]

However, the thought is intriguing of what one could do with a 2L Miata and liberal application of the legal rules.

..and that's what I'm asking: what's the worst-case scenario?

[Clarkson]How bad could it be...?[/Clarkson]

 

[Chip42]

I'm playing Devil's Advocate here, not intending to pick on you. I agree with what you're suggesting, but...

>>> original angular orientation and the bellhousing plane can be part of the VTS requirements.

There are no VTS for cars in Super Touring U and L. Anything can run in that class with the appropriate engine. And there won't be any VTS for engines except non-US market engines.

using VTS in the vaguest of senses here. if the doner car and engine are USDM, then refeences are available. you made a point that this would be hard to tech for non USDM doner cars. have non USDM doner engines include this information in their listing when they are permitted. soup.

>>> make a specific year range and model of car(s) part of the alternative engine allowance.

Unfortunately, that's cat's long out of the bag, unlikely to be further restricted. But to do so would require a wholesale change in the philosophy, in addition to having to specifically approve each and every possible combination, immediately making any swap non-compliant until the STAC/CRB goes through the process of approving them. And given our slow lead times (request ->STAC ->CRB -> Fastrack) we'd be holding people up until we did.

again, the cvomment was with regard to newly approved, non USDM motors.

It'll probably bite us in the ass eventually, but I just can't see moving from an "open" philosophy to a "permitted only".

was a misread - I'm trying to point out a way that you can regulate transplant placement going forwar din any way that you want. if the info becomes irrelvat due to openness, fine. if you (the STAC) decide to place limits on engine position / orientation, you have that available for the "hard to tech" engines from other markets. it CAN get ugly, I'm sure a lot of people might have issue with transplant or stock motors being set back, down, and/or roatated as Ron suggests (they did take back some of these allowances in STO not too long ago, so there's your precedent). what your job is to do is to decide if you want to see how bad it is (fully open), or set up limits and adjust them as you see fit in the future. I vote #2.

>>> BTW, are shift linkage / trans housing modifications legal to allow for swaps?

Can't say for sure without specifics - and it's not really mine to say - but I would suggest it's compliant to change a car from cable to rod or hydraulic shift, if that's what the desired trans used.

I'm thinking FWD trnasaxle in a mid engined car (I'm MR2 centric) - inputs are on the "wrong" side of the case. easy button for the 4A/3S/2ZZ series is use the center section from the trans that came with some MR2 with the same trans series, but it's easy enough to adapt many of the cases too. just wondering if that is legal (seems to fit the roffe corollary and the spirit of the swap allowance)

>>> AND of the car as a whole allowing the chassis to be set lower without CV axle bind and better weight balance...

Note ST classes each have minimum ride height.

GA

yeah, they do, but sometimes, particularly with FWD cars, you can't even GET to the allowed ride height due to axle bind (maybe only in roll but still there) and even if you can, you can still make the system better by bringing the axles into alignment. is the diff position open in RWD IRS cars?

 

[TStiles]

..and that's what I'm asking: what's the worst-case scenario?

[Clarkson]How bad could it be...?[/Clarkson]

Worst case scenario is that guys like me ( with limited budgets and technical expertise ) say the price to play is too high and we do something else.

Allowing more and more modifications is not how I would grow the ST classes.

The guys with healthy budgets and technical skills already have GT classes and Prod classes.

Maybe the compromise position is to allow the wide open stuff in STO & STU and keep STL more of a bolt on class before it gets out of control.

 

[Greg Amy]

if the doner car and engine are USDM, then refeences are available.

Where in the FSM - our "bible" for technical reference - is the location of the engine specified? And if it's there, can that be easily measured at the track with basic tools, or do we have to bring it to a frame machine?

Show me, because an unenforceable limit is not a limit (see "tech shed legal").

I'm thinking FWD trnasaxle in a mid engined car (I'm MR2 centric) - inputs are on the "wrong" side of the case. easy button for the 4A/3S/2ZZ...

Can't offer an educated opinion on that one, unfortunately.

...is the diff position open in RWD IRS cars?

No, not that I can see.

Worst case scenario is that guys like me ( with limited budgets and technical expertise ) say the price to play is too high and we do something else.

Even STL ain't gonna be cheap, and it's going to be much, much worse within the National racing program (see the Knestis corollary). When people are spending $55k+ for a Spec Miata, you can be assured we're talking much more than that for a full-up Super Touring build, even for Light.

Right now, not so much an issue; I can win STL races today in my ITS+ Integra. But as that class vies for a National Championship and the interest grows - and I'm very confident it will - you can count on that opportunity quickly disappearing.

I'm not trying to discourage you from interest and participation, I'm simply trying to say where I predict this class is going.

Maybe the compromise position is to allow the wide open stuff in STO & STU and keep STL more of a bolt on class before it gets out of control.

I tried that and was dismissed. See prior letters from me from late 2010/early 2011 in regard to limiting seam welding, glass and panel replacements, multi-point rollcages. That cat's done gone well and truly out of the bag.

STL is a lower prep version, but it won't ever be a low prep version.

GA

 

[DoubleXL240Z]

STL is a lower prep version, but it won't ever be a low prep version.

Isn't that what IT is for?

On another note!!
Somebody check my math:
Original plans: E30 with M42 1.8l 4 cyl(1.3)=2340 base weight= RWD adder 58.50=2398.5=2399 lbs
Then the increase
plans: E30 with M42 1.8l cyl(1.35)= 2430 base weight+ RWD adder 60.75= 2490.75= 2491 lbs
Future was: E30 with something something 2.0l(1.35)= 2700 base weight+RWD adder 67.50= 2767.5=2768 lbs
therefore my 1.5x.095 cage is no longer an option as my weight has exceeded 2700?
So I'm pickled?? Or STU bound?