Your car sounds very similar spec to mine. i have quite a bit of carbon but then i also have paddleshift compressor so the weight would even itself out in comparism. I was quite surprised how heavy it was.

I guess I shouldnt be that proud of being 2900lbs with a 1/2 cage and full tank of gas lol. Though I have not gutted the doors and have stock subframes and OE glass.

2900 isn't bad at all. The glass and door guts are a fair bit of weight. With my quick release door hinges I can pull the door off the car and carry it around with one arm lol

How much weight does the full cage add?

With my current setup I have a list of SM legal weight reduction I can lose about 100lbs more weight and Im at 3005lbs now with 315s and wood splitter. And I have ZERO weight reduction only mods from the rear of the car. My car is full interior, lights, wipers, etc. I've only pulled the AC and Radio for creature comforts.

With XA rules now, I have 100lbs I can pull off the front of the car but then have to add it back to the rear.

This would be a generalisation and a bit of an estimate but id say about 120LB for the bars.

Factory to carbon doors is a 137lb saving according to a guy who did it and weighed them on an old forum post i found.

Just cutting the glass and intrusion bars out is 40 - 50lb

This is a small list ive compiled of weight saving opportunities. this is just from scouring through some of the old weight loss and weight measuring threads and google.

Weights are all in KG sorry. and to note the weight factory i have for doors is for gutted doors not OEM with glass and intrusion. saving there is 135lb if fully factory

https://cimg4.ibsrv.net/gimg/www.evo...d0502a8072.png

is there any part of removing exhaust manifold, intake manifold, downpipe, knock sensor that would require loosening a coolant line? I was down on coolant again after some work, just checking

If they unbolted the turbo the coolant lines are running there. Also there are coolant lines running to the throttle body unless bypassed.

thanks, yeah that was probably what it was

Is there any real benefit to installing the RS trunk bar if you have the rear US crash beam? I understand why it would be beneficial on a JDM car with them not having the rear crash beam at all, but on the US cars the beam is already like a thick brace that bolts to both frame rails.

Same with the front crash beam. I wouldn't be surprised if the US spec Evo 8/9's were the most rigid models as they were certainly amongst the heaviest..

I run stm's front and rear crash beams. the front crash beam probably saved my motor after a track incident. crash beams are for crashes, not rigidity. not sure re: the rs trunk bar but I run it as well. haven't noticed anything one way or the other, but it's not a bad place to have a small amount of weight

Youd have to test to be sure but I don't think crash beams do anything in the way of rigidity. That's what roll bars, strut tower bars and other bracing including the rs bar does. Crash beams are at the furthest front and rear past the "flex" points of the chassis. Their sole function is to absorb impact.

also since you mentioned models, can someone confirm the evo 9 has something like an extra 200 spot welds to further strengthen the chassis? An improvement from the 8 I read on a post years back.

Yeah I know they are for impacts, but I'd be willing to bet they have some benefit in rigidity even in the slightest amount. The rear crash beam massive and bolts directly into the frame rails mere inches away from where the RS trunk bar is mounted so it just makes me wonder if sort of accomplishes the same thing.

The RS bar is also pretty far out on the end of the frame rails. The S15 Spec R had so many chassis improvements over its predecessor (s14) and also had a very similar bar in the trunk. It also had a number of ladder bar braces and small bolt-on sheet metal brackets in various parts of the chassis that resulted in much better chassis rigidity. Its interesting to see the similarities in chassis bracing across different manufacturers, even if they are all based on your typical conventional unibodies

Everything Ive read has indicated the 8 and 9 chassis's are identical.

seems like after the work (basically intake mani, exhaust mani, downpipe, knock sensor) my AC compressor is not working. anyone have any ideas what could be causing this? it doesnt seem like the compressor is kicking in at all, is there possibly a connection that was left disconnected with the work?