Teach me about ITR 325's

[JLawton]

IT is way too rule crazy.

You think so??? Go onto the Prod sites. That whole thing is insane!!

It really isn't crazy, it's just that people try to twist the rules to fit their need. Yeah, there's some silly things but they're all meant to keep IT from turning into Prod.



The bottom line on the original request: The BMW is a great car. Solid, reliable, proven winner, lots of good information and lots of after market support. You won't be kicking yourself in two years becasue the car is uncompetative.




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[Spinnetti]

You think so??? Go onto the Prod sites. That whole thing is insane!!

It really isn't crazy, it's just that people try to twist the rules to fit their need. Yeah, there's some silly things but they're all meant to keep IT from turning into Prod.



The bottom line on the original request: The BMW is a great car. Solid, reliable, proven winner, lots of good information and lots of after market support. You won't be kicking yourself in two years becasue the car is uncompetative.
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Yeah, I'm thinking about one too actually after decades trying to stay up front with a non-front running type car. Almost seems a sellout to run what everybody else does though! I saw several comments about VANOS - is it 93 and up or 94 and up I should be looking for?

As to rules, I'm contrasting IT where people complain if a windshield washer nozzle is aimed at 5 vs. 6 degrees to the "Lemons race" where anything goes, yet somehow, the competition is still pretty even.. believe it or not, I've been finding Lemons more fun, and am doing two events this year.

[tnord]

i'd run one, i think.

before i did it i would want to find out just how long one can expect to go before the subframe mounts need to be cut out and new pieces welded in. i'd want to know what that costs, and how hard the necessary parts (OEM factory installed!!!!) are to come by. if it's reasonable, i would then move on to finding the weight/power balance i thought was best for ITR. i know the thread title says "325" but i'd look very hard at what the 328 weight is, and find out what the restriction point is in both motors. the 325 should be easier because the development has been done for ITS, but the extra displacement of the 328 might provide a torque advantage that suits your local tracks better.

my final question would be....what line of work are you in that you're building a new ITR BMW right after an ITR Prelude, and are you hiring?!

[ekim952522000]

i'd run one, i think.

before i did it i would want to find out just how long one can expect to go before the subframe mounts need to be cut out and new pieces welded in. i'd want to know what that costs, and how hard the necessary parts (OEM factory installed!!!!) are to come by. if it's reasonable, i would then move on to finding the weight/power balance i thought was best for ITR. i know the thread title says "325" but i'd look very hard at what the 328 weight is, and find out what the restriction point is in both motors. the 325 should be easier because the development has been done for ITS, but the extra displacement of the 328 might provide a torque advantage that suits your local tracks better.

my final question would be....what line of work are you in that you're building a new ITR BMW right after an ITR Prelude, and are you hiring?!

Does the 328 have the same rear subframe issue? f it does the 325 makes more sense to me if it does not then maybe the 328 is the way to go. Used version of each can be found for close to the same price.

[JoshS]

Does the 328 have the same rear subframe issue? f it does the 325 makes more sense to me if it does not then maybe the 328 is the way to go. Used version of each can be found for close to the same price.

Yes, it does. Same chassis, same issues.

The 328i has more torque but worse top-end because of a lousy intake manifold.

[mlytle]

i'd run one, i think.

before i did it i would want to find out just how long one can expect to go before the subframe mounts need to be cut out and new pieces welded in. i'd want to know what that costs, and how hard the necessary parts (OEM factory installed!!!!) are to come by. if it's reasonable, i would then move on to finding the weight/power balance i thought was best for ITR.

they don't all do this. what drives the subframe failure is not replacing bushings when they wear out. the stock bushings are rubber. when they get old they loosen up and allow the subframe to move a little. this movement gradually flexes the mounting studs at the passeger side front first. the constant flexing causes the metal in the chasisis around the stud to fail. if you get a car that shows no signs of failure and put solid/urethane bushings in, you are good to go. if the flex has started, repair is needed. the repair is the installation of the factory plates that weld on around where the mounting studs/bolts go into the chassis. the plates are readily available at any dealer or place like bimmerworld. they are cheap too, like $20. the cost comes in labor to drop the subframe and weld the plates on, if you don't do this yourself. it really isn't that hard. nor is it necessarily required.

[JoshS]

if the flex has started, repair is needed. the repair is the installation of the factory plates that weld on around where the mounting studs/bolts go into the chassis. the plates are readily available at any dealer or place like bimmerworld. they are cheap too, like $20. the cost comes in labor to drop the subframe and weld the plates on, if you don't do this yourself. it really isn't that hard. nor is it necessarily required.

Marshall, I'm genuinely curious -- what document makes this repair legal on an IT 325i?

FYI, the Z3s have a different rear suspension design altogether, but have a very similar failure. When the bushings get worn, the rear subframe moves around a lot and can basically destroy the trunk floor. It's really ugly, much uglier than the E36 failures, when it happens. However, unlike with the 3-series, there is no reinforcement available from another BMW model. There is reinforcement available in the aftermarket ... of course, that reinforcement would be totally illegal in IT.

[mlytle]

Marshall, I'm genuinely curious -- what document makes this repair legal on an IT 325i?

FYI, the Z3s have a different rear suspension design altogether, but have a very similar failure. When the bushings get worn, the rear subframe moves around a lot and can basically destroy the trunk floor. It's really ugly, much uglier than the E36 failures, when it happens. However, unlike with the 3-series, there is no reinforcement available from another BMW model. There is reinforcement available in the aftermarket ... of course, that reinforcement would be totally illegal in IT.

the 325 reinforcement is not "from another model" it is for repair of the non-m3 e36's. the m3's came from the factory with reinforcement standard..they don't need it, nor can they use it.

yep, the z3's got the suspension from the e30's. rips in a difficult place. e36's rip in a place that is easily fixable with a plate.

i gotta stop here...this is a really dead horse being kicked.

[JoshS]

the 325 reinforcement is not "from another model" it is for repair of the non-m3 e36's. the m3's came from the factory with reinforcement standard..they don't need it, nor can they use it.

I hear people saying this a lot, but I'm asking ... why does everyone believe it? Seems like it's become common knowledge with no official basis. What BMW document says that what those parts are for?

And if you do a parts search for those part numbers, they come up as M3 parts (and not any other E36).