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phenryiv1
10-01-2009, 02:01 PM
Mods- sorry if this is in the wrong place! :tongue:

I have an 88 E30 325 (not "e", not "i"- NOTHING).

It (I assume) gets classed with the other 325 "e"/eta cars, because that is the motor that is in it. Seems easy enough.

Now, if I swap just the TOP of an "i" onto the "e" bottom end, I don't change anything about the displacement, but I do increase airflow on the intake side.

Where do I end up being classed? My thought is Tuner 3 or 4. My "base" car is the 325e, while I don't have a motor swap, so the logic of swapped motors moving you to the class of the origin car does not seem to fit. The motor is not really built, and even the head is the same on my 88 as it is on the "i" cars.

I am basically swapping in intake, throttle body, and other intake-related parts. It falls somewhere beyond the "Cold Air Intakes (Before Air Flow Meter) Permitted" of Tuner, but does not really change engine internals- just peripherials.

Help? :confused:

Scany
10-03-2009, 11:30 PM
I would think your car is still classed as a 325e, but since modifications go beyond a CAI, and not limited to a manifold change, which seems allowed in Tuner, you seem to me to end up in Group 4 Modified. If by "top" you mean the entire head, I would for sure think you're in Modified.

phenryiv1
10-04-2009, 09:12 AM
I would think your car is still classed as a 325e, but since modifications go beyond a CAI, and not limited to a manifold change, which seems allowed in Tuner, you seem to me to end up in Group 4 Modified. If by "top" you mean the entire head, I would for sure think you're in Modified.
The head is actually the same. In both cases, it is an 885 head. The super eta cars in 88 got the same head as the "I" cars, but got a more restrictive intake.

I want to swap in the less restrictive intake parts.

Scany
10-04-2009, 12:39 PM
The head is actually the same. In both cases, it is an 885 head. The super eta cars in 88 got the same head as the "I" cars, but got a more restrictive intake.

I want to swap in the less restrictive intake parts.

I see. With a new throttle body you would end up in Modified however. I would maybe make a point of this because the rules seems to allow a M50 manifold onto an M52 and stay in Tuner, as well as a Weber carb, but a throttlebody swap in your case bumps you to Modified. Join the classing discussion Jonathan hosts and give your input for the 2010 season.

Plenty of room in M4 though :biggrin: I'm not running my 318is anymore, but it would have been fun to have a bigger M4 group.

phenryiv1
10-04-2009, 05:35 PM
I see. With a new throttle body you would end up in Modified however. I would maybe make a point of this because the rules seems to allow a M50 manifold onto an M52 and stay in Tuner, as well as a Weber carb, but a throttlebody swap in your case bumps you to Modified. Join the classing discussion Jonathan hosts and give your input for the 2010 season.

Plenty of room in M4 though :biggrin: I'm not running my 318is anymore, but it would have been fun to have a bigger M4 group.
It is kind of a wash, M4 or T3, I'd think.

Iddly, the swap if the parts is still all stock BMW stuff that was offered as stock equipment on a Class 3 vehicle. I could swap the whole motor in and just be in C3 Stock (or C3 Tuner, at worst), but putting PART of a C3 motor in a C4 makes me C4 Modified.

I know the system isn't perfect, but all of the frankenstein cars and builds have to get classed somehow.

Maybe there could be a case-by-case for oddballs. Then again, maybe just an appel process for oddballs. The rules cover 95% of what shows up at the events...

woodym3
10-05-2009, 08:46 AM
This head swap sounds like a "Modified" car to me. Remember the 325i has a 2.5-liter engine whereas the 325 e / eta / no letter has 2.7-liters. Back in the day, lots of guys were making this swap and the result was a very fast 3-series IF they also swapped for a higher numerically diff ratio. As I recall, the eta cars have a 2.93.

phenryiv1
10-05-2009, 08:50 AM
This head swap sounds like a "Modified" car to me. Remember the 325i has a 2.5-liter engine whereas the 325 e / eta / no letter has 2.7-liters. Back in the day, lots of guys were making this swap and the result was a very fast 3-series IF they also swapped for a higher numerically diff ratio. As I recall, the eta cars have a 2.93.
I want the car to be as fun as possible, but I also don't want to get outclassed based on vehicle alone. My skills will put me at enough of a disadvantage as it is. :biggrin:

I can see where the M4 would probably be the most appropriate from a powerplant standpoint, but the lack of any other mod that would otherwise throw me in modified is going to kill me if I drive the car before it is "finished." (EDIT: Also, as noted above, it isn't really a head swap (as you mentioned) because both my car and the donor come stock with an 885 head. My 88 S-eta is uniquie in that "eta" cars in 88 got the same head as the "i" cars received- just for that one year. I AM, however, swapping in the "i" cam and valve springs. End Edit)

While the engine may be done in the next few months, there will be a lot of other things that remain incomplete for quite some time!

And you are correct: my eta has a 2.93- but it is the LSD version!

phenryiv1
10-05-2009, 09:01 AM
http://www.nccbmwcca.org/index.php?option=com_content&view=article&id=41&Itemid=166

Posting that link so that I can find it more easily. (I am lazy!)

phenryiv1
12-02-2009, 09:45 AM
Bumping this to ask:

Where is the best way to get clarification on where this will class me?

I am about to embark on a LOT of other stuff that would otherwise keep me in Tuner. The only REAL item of contention would be the cam swap from the "i" to the eta top end.

I am not saying that if that single part puts me in modified that I won't go ahead and do it, but if that single part makes me clearly in modified, then I might as well throw in other parts that would put me there as well.

EVERY other planned mod is clearly a "Tuner-"legal modification.

Edit: And I can't make the meeting on the 5th (family time commitment), but is this the sort of thing that can be discussed there?

Nick325xiT 5spd
12-02-2009, 10:24 AM
There is no question about it. You're going to Modified.

While the current version of the NCC rules is not what I would have written (or what anyone who is serious about writing a good set of competition rules would have written), I doubt that anyone would argue with you if you did a full i conversion. Put in a 2.5, swap in the correct diff and run it as a 325i.

Reach
12-02-2009, 04:06 PM
Hopefully you should have more competition in Modified next year as well. The committee is looking at several adjustments for the upcoming year. They will be discussed on the 5th.

Frankly, I would never let NCC's autocross classifications stop me from doing any mod I wanted to my car. Go at it and make it the most fun street machine you can. The increase in car will make up for the decrease in local BMW competition. Plus, you can always call the guys from the next class up and point out that your times are significantly faster than theirs. (or slower, in my case :))

SamB325es
12-02-2009, 04:27 PM
There is no question about it. You're going to Modified.

While the current version of the NCC rules is not what I would have written (or what anyone who is serious about writing a good set of competition rules would have written), I doubt that anyone would argue with you if you did a full i conversion. Put in a 2.5, swap in the correct diff and run it as a 325i.


If you feel this strongly, you should come to the meeting on the 5th and show us how to do it correctly. If it is not SCCA, classing will always be arbitrary. No one builds cars to BMWCCA auto-x classing.

If you want an 325i you should sell the e and buy an i.

phenryiv1
12-02-2009, 05:44 PM
If you feel this strongly, you should come to the meeting on the 5th and show us how to do it correctly. If it is not SCCA, classing will always be arbitrary. No one builds cars to BMWCCA auto-x classing.

If you want an 325i you should sell the e and buy an i.
I don't think his post was meant to be a stab at the organizers (or maybe it was...I just did nto read it that way), but the line between stock and tuner is pretty logical. Stock=stock and anything else is NOT stock...sort of.

What BMW classing allows (but SCCA does not) is for little things like stainless steel lines. That is a good thing, IMO.

I just find it funny that if I swap in a complete M50 from an E36, I am in Tuner 3 (the same class as an E30 325i), but if I swap the CAM from another M20 that was offered the same year as my vehicle, I am in Modified 3. (The M50 swap example assumes that all other mods are tuner-legal, of course.)

Hell, if I swap in an M50 from an E34, technically, I am still in Group 4.

It just seems a bit off-kilter to me.

Maybe the internal engine modifications need to be clarified. Something like "aftermarket cam/pistons/etc. forbidden" for Tuner, but Open for Modified.

Or, just let drivers petition on a case-by-case basis at the beginning of the season.

The idea that you can run a downdraft carb but not an M30 throttle body and/or AFM is also a bit weird.

I don't envy those who have to make the rules, but I see small areas for improvement.

Biggins
12-02-2009, 09:53 PM
Where is the best way to get clarification on where this will class me?

I am about to embark on a LOT of other stuff that would otherwise keep me in Tuner. The only REAL item of contention would be the cam swap from the "i" to the eta top end.
My interpretation from the way the rules are written today is that you would be in Modified. If you swapped an entire "i" motor into your eta, you'd be in Tuner. If you were running that motor in Tuner against me, I would not care... However, I think that you should be running Tuner 3 instead of 4 with this upgrade.

I'd compare this to the classic Honda/Acura swap of an LS/VTEC Integra motor with a GS-R/Si head which lands in SM in SCCA. Like in SCCA, and depending on the Honda, you could swap an entire GS-R/Si motor in and still run SP.

I'll see if I can bring this up at the meeting along with the other points I'd like to see changed/addressed.

Nick325xiT 5spd
12-02-2009, 10:22 PM
I don't think his post was meant to be a stab at the organizers (or maybe it was...I just did nto read it that way), but the line between stock and tuner is pretty logical. Stock=stock and anything else is NOT stock...sort of.

What BMW classing allows (but SCCA does not) is for little things like stainless steel lines. That is a good thing, IMO.

I just find it funny that if I swap in a complete M50 from an E36, I am in Tuner 3 (the same class as an E30 325i), but if I swap the CAM from another M20 that was offered the same year as my vehicle, I am in Modified 3. (The M50 swap example assumes that all other mods are tuner-legal, of course.)

Hell, if I swap in an M50 from an E34, technically, I am still in Group 4.

It just seems a bit off-kilter to me.

Maybe the internal engine modifications need to be clarified. Something like "aftermarket cam/pistons/etc. forbidden" for Tuner, but Open for Modified.

Or, just let drivers petition on a case-by-case basis at the beginning of the season.

The idea that you can run a downdraft carb but not an M30 throttle body and/or AFM is also a bit weird.

I don't envy those who have to make the rules, but I see small areas for improvement.
The rules as is allow far, far, far too much of that (and yet are very restrictive in other ways).

Bob
12-02-2009, 10:47 PM
I could have run in modified with my stripped E30/M50, non stock FI is the only restriction. I never got the blower mounted, but look out next year.

95Maxrider
12-03-2009, 03:54 PM
Or, just let drivers petition on a case-by-case basis at the beginning of the season.

The idea that you can run a downdraft carb but not an M30 throttle body and/or AFM is also a bit weird.

I don't envy those who have to make the rules, but I see small areas for improvement.

I think the idea of case-by-case judgment is a good one. Very few people are going to be in a situation that isn't clearly (or logically) defined by the rules, so I don't think too much time would be wasted on this sort of thing.

woodym3
12-03-2009, 05:06 PM
While the current version of the NCC rules is not what I would have written (or what anyone who is serious about writing a good set of competition rules would have written.

I'd be curious to see how you would have written them Nick.

KatieT
12-05-2009, 12:38 PM
Since people were talking about the meeting in this thread I'll post here too. We've postponed the meeting tonight due to the white fluffy stuff outside. Watch the forum to see when the meeting will be rescheduled.

~Katie

phenryiv1
12-05-2009, 12:48 PM
Since people were talking about the meeting in this thread I'll post here too. We've postponed the meeting tonight due to the white fluffy stuff outside. Watch the forum to see when the meeting will be rescheduled.

~Katie
Good to know. My wife is due to deliver any day now, and it is about a 2 hour trip (each way) to make the meeting, so I (most likely) won't make it even after the reschedule.

At any rate, I emailed my 2 suggestions directly to Jonathan.