Up the BMW 330 ZHP performance...

[jjcools]

I wanted to see if anyone has done the 2nd resonator delete. I saw a couple of clips on Youtube with guys that had cut those out and added an x pipe in place. Is the performance exhaust on it really better than the other bmw exhaust?

What is the best bang for the buck performance upgrade for the Zhp? Coilovers? Intake?

Just a question for people that have improved their Zhp, what did you like that you did and what did you regret?

[Alphatek45]

I'm also interested in pure horsepower mod details.
I know what I want otherwise.

[danewilson77]

This would be a perfect question for our performance subforum...

[danewilson77]

Performance wise...I will be upgrading the brake pads, lines, fluid, and rotors, as well as the suspension, with FK Silverline coilovers. I have ECSTuning CF strut bar, and will probably end up getting the AFE intake.

That'll be it for me....maybe.

[thesixsins]

Supercharger.

[Marcus-SanDiego]

Supercharger.

+1

[jjcools]

Dane, why the Afe over the BMW performance since the price is so nice right now?

[Marcus-SanDiego]

I recently had the AFE. I swapped it out for the BMW Performance intake. I can't tell the difference between the two. Additionally, I want as many OEM parts on my car as possible, which is why I swapped the AFE out.

[3ZHP]

Performance wise, I think my Turner under-drive pulleys gave me a greater gain then my Dinan intake. Don't get me wrong, they are great together but with the pulley change you could feel the difference, with the Dinan you can hear the difference. As for the handling, the Potenza RE11s are great on the track. Upgrades for next season are going to be new struts. Probably Koni Sports. Why, because of getting black flagged at the track and nicknamed THUMPPER by my instructor. Should have done it first, so I could have had more fun.

[danewilson77]

Dane, why the Afe over the BMW performance since the price is so nice right now?

Though I love the BMW performance, I feel like Marcus and I need to build up our platforms in different directions, for the good of the zhpmafia name, and to make us a more diversified knowledge forum. That is the only reason I would go afe.

His car will end up being more of a purists zhp, while mine will be the result of many different products.

Also, helps me in giving you all good reviews on various products.

You guys all, are at the very forefront of my mind whenever I do something to my car.

[jjcools]

Wow, Dane, we thank you for your selflessness!! ;)

[danewilson77]

I'm also interested in pure horsepower mod details.
I know what I want otherwise.


This is what I plan as my next performance mod, and so I hear, this will fit in the trunk......


















































http://i1015.photobucket.com/albums/af278/nicee46/Funny/IMG_20101020_100113.jpg

[Alphatek45]

Already have one ^
Not enough power. Still need moar.

[mimalmo]

Most of you have probably read this thread that I frequently post from E46Fanatics regarding getting more power for the ZHP. If not, sit down and take your time; it's got a ton of spot-on correct info. This would be the route to go if you didn't want to go with FI (forced induction) from either a turbo or SC (supercharger).

Post #6
http://forum.e46fanatics.com/showthread.php?t=625874


I would have copied and pasted the whole thing here but currently we are limited to 1,000 characters in a single post and that one is over 1,400. Maybe something worth changing Marcus?

EDIT: pasting here now since Marcus had the text character limits upped. Thanks man!


Well, it depends on how much you want to spend... At the point you're at, it would be worth it to lose some of the Dinan and get some of the "real powermaking stuff".

Which cold air intake do you have from them? The CF one that is an actual TUBE that goes into the fender/bumper to get cold air? If so, keep it.

Next up, you should get some Ebay Headers (search if you don't know what they are), some Random Technology 100cell Metallic Core Catalytic Converters, and have your exhaust/performance shop install them both, with the cats just downstream from the headers. Then, have all of the resonators/silencers chopped off of the Dinan exhaust, essentially giving you straight-pipes with a muffler. It will be loud, but you will gain low-end and top-end power.

If you don't have the "true CAI" from Dinan, sell the one you have and get an AFE Stage1 intake. They are the BEST, most consistent intakes on the market for non-M E46's.

Ditch the Dinan software and switch it up for the newly-released Conforti Shark Injector for your car. It will give you a higher redline, no top-speed, more power, and much better throttle response, even over the Dinan S4.

You are losing power to parasitic drive from the engine, such as Power Steering, Waterpump, Flywheel, Driveshaft, etc. You CAN GAIN THIS HP BACK by using lighter-weight, under-driven components.

First, get a set of Evo-Sport Under-Drive Pulleys. You'll also probably want to get a Stewart Water Pump (less parasitic drag, 20% more flow, lifetime warranty; TOP of the line!) and just fix up your cooling system now. Install the pulleys, the water pump, and get a new thermostat and housing, expansion tank, radiator hoses, and flush the coolant and put new BMW Coolant in. This should give up to 13hp on your car.
You will also notice an increase in throttle response, thanks to the under-drive pulleys.

Now, you want to lessen the engine's load even more. Get a Stage 1 Organic Clutch from UUC, and get the 8.5/9lb flywheel that they have. Since you're not going F/I, it will work great. Your stock flywheel is 28-30lbs. You are cutting off a LOT of weight RIGHT at the source! It should feel like you gained 20+ horsepower. The clutch will be a ton better; have them intall a SS clutch line, too.

You probably have about 260hp at the crank, but you've gone from about a 17% drivetrain loss to about a 12-13% drivetrain loss. This means you GAINED REAR WHEEL HORSEPOWER but your engine REMAINED THE SAME in terms of power-output. This is a good thing, because it's less strain on the engine.

Now, you still want to go faster... Something we haven't addressed yet, is unsprung weight. Your stock M135's are HEAVY wheels. If you truly are more after power/speed than you are style, get yourself a set of Kosei K1 in 18x8 and 18x9 sizes (staggered F/R) and put on some super-sticky tires, like Nitto Invos. These wheels weigh about 18lbs for the front and about 18.5lbs for the rear. They are, however, strong; at least as strong as your OEM wheels, which, btw, weight almost 30lbs a piece.
So, total weight savings is around 45-50 POUNDS of UNSPRUNG WEIGHT! That is like saving 450-500lbs of weight from the inside of your car, only way better!
You should notice the equivalent of gaining about 30hp with this. Your car will absolutely ROCKET through gears, and will pull harder in ANY gear, regardless of engine speed. It's one of the best mods you can do, lightweight wheels, that is.


Now, to get any more power out of your engine, you're going to have to open up the engine and install new cams. Schrick makes good camshafts for our cars, and usually have a "Stage1/2/3". Stage1 cams will give you more mid-rang and top-end power, but you won't feel a difference down low. Stage2 cams, you'll feel a bit of a torque/power loss down low, but you'll have moderate gains in the mid-end and notable gains up top. Stage3 are not recommended unless this is a track-beast, because you WILL LOSE a LOT of down-low power in exchange for a significant bump in mid-range torque and a huge increase in high-end power.

Lets say you go with Stage2. Your bottom-end will feel more like it did stock (basically, you'll lose the power that the mods gave you down low), but after about 3k RPM's, you'll start to feel the engine pulling harder, harder than it ever has. Once you hit around 4.8-5.2k rpms, your car will feel like a ROCKET!
You can expect peak-gains of around 20+hp and 17-25ft-lbs/trq. These are going to be at high rpms, though, and your Dyno-Chart will show a loss in power down below about 3k rpms. If this is worth it to you, then do it! If not, don't.

With cams, you can also install new valves/valve-springs/lifters/retainers, and port and polish your head. Doing a FULL head-job, including Stage2 cams, you can expect maybe 45hp, given that your car flows so freely. The cost is going to be equal to, if not greater than, a supercharger, so if it's worth it... By all means, have a BADAZZ normally-aspirated car! You'll be looking at around 285-300 crank horsepower with this set-up.
Below 3k rpms, you'll have stock-ish, or slightly higher than stock, power. Above that, your power will rise exponentially with the RPMs. If you can keep the engne running between 4500-7000rpms when you're "pushing her hard", you will not only have a car that SOUND MEANER than anything else in probably a 100-mile radius (with the straight-pipes, it will sound like a flat-out race car; but when idling, driving normally, or whatnot, it will be about as tame as a housecat), but it will accelerate like a BAT out of HELL!! If you've ever driven, say, a Honda S2000, you know how you have to keep the revs up to keep the power coming on, right?
Well, imagine "Honda S2000, except a 3.0L I6 instead of a 2.2L I4, a full port-and-polish headjob w/ titanium valve-springs and retainers, a 7500-8000rpm Redline, 250-270ft-lbs/trq at around 4500rpm (probably 180ft-lbs at 3000rpm), 18lb 18" wheels, a lightweight flywheel so you can rev-match super-easy, and straight-pipes so that your car sounds like a BMW-Sauber F1 car (with NO drone!)". Oh, and it can seat 5, carry the dog to the park, and does't look anything like a true sports car (unlike the S2000).

Drooling yet?


Now, we've addressed the Normally Aspirated power part. You're probably around $8k broker, but your car needs to handle, stop, and look as good as it accelerates! I mean, you have a high-12sec 1/4mile car, but it doesn't look like it can pull anything faster than a high-14sec run.

First, the twisties. This is basic, and I recommend a similar set-up to everyone. However you are a bit different, because You NEED some things that other people don't (adjustable valving on shocks, for example), and HAVE things other people want (3.07:1 diff ratio).

For a car that will handle better than you'd ever expect, I recommend:

- KW Variant 2 Coil-Overs ($1500): Adjustable height and damping, so that you can set the car to perfectly "set" when you launch it, so that you can out-handle a "true sportscar" like an S2000 or stock Miata in the twisties (or even a stock M3, if you do this all and do it right), and also so that you can take thee family to diner and it will ride so gently that Junior there in his Recaro Car Seat doesn't wake up even when you hit every possible pot-hole on the road home.
Since they are height-adjustable, you can lower as much as possible and thus not only making your car look much better, but also giving you a lower center of gravity, in turn making your car handle better.

- Kosei K1 Wheels 18x8F 18x9R ($1000-1500): Put on Nitto Invo tires 235/40R18 front and 255/35R18 rar, giving ou more meat to hook-up with, and to keep you planted as you're pulling high-g maneuvers through the local curvy roads. They are surprisingly comfortably tires, too, and have almost no road noise, so passengers won't realize that they're riding on some of the most technically advanced tires around.

This post is running on too long, so I'l end here. Coil-overs are the bread to to the rest of the (upgradable) supension's butter, so puttng those in makes as much of a difference as all of the other parts combined, perhaps.

If you want, I'll give you more information. I'd recommend the following parts, though:
- Quaife 3.23 Limited Slip Differential (part-go, part-handling mod: this is essential if you're making good power and want to handle, as it lets BOTH wheels put down power, NOT JUST ONE! Going from a 3.07 to a 3.23 rear end also gives you a better torque-multiplier, meaning more low-end grunt as your engine will sping the gears faster. However, you'll also run higher RPMS at a given MPH in a given gear, but your 6-speed should compensate)
- Hotchkis H-Sport Front and Rear Adjustable Sway Bars and Endlinks
- Rogue Engineering Rear Shock Mounts
- Meyle HD Front Control Arms
- PowerFlex Front Control Arm Bushngs
- PowerFlex Rear Trailing Toe Arm Bushings
- Turmer Motorsport Subframe Reinforcement Kit (F/R subframes, swaybar mounts, and more)
- Turner Motorsport Solid Differential Mounts/Bushings
- Turner Motorsport Semi-Solid "Race" Subframe Bushings
- StrutBarbarian Front and Rear Strut bars
- TMS Stage2 Front Adjustable Camber Plates
- TMS Aluminum Adjustable Rear Control Arms
- Turner Motorsport Solid Engine and Transmission Mounts

With those, your car will literally handle as good as, if not better than, some/most purpose-built race-cars, but will still be perfectly comfortable to drive on the street. You'll get "creaking" from some of the solid-bushings, and it WILL be harsher, but it is easily do-able.

Brakes:
- AP Racing BBK 6-Piston Monoblock Calipers and 355mm Vented 2-Piece Slotted Rotors (FRONT)
- AP Racing BBK 4-Piston Monoblock Calipers and 328mm Vented 1-Piece Slotted Rotors (REAR)
- StopTech Stainless Steel Brake Lines
- Motul RBF600 Brake Fluid

This is an Expensive set-up, but it will retain F/R brake-bias, and will also be so strong that you'd need tires 50% wider than you have before you'd have to worry about these brakes being anywhere even remotely close to less-than-TOO-powerful. But, they dissipate heat like NO OTHER, and that's what you need: coooool brakes. Plus, they look MONSTROUS behind the thing spokes of your wheels.

Looks/Aerodynamics/Weight-Reduction:
- BMW Carbon-Fiber Clubsport Splitters
- Vorsteiner Double-Sided Carbon Fiber M3-GTR Hood (Vented)
- Vorsteiner Double-Sided Carbon Fiber M3 CSL-style Trunk
- Hartge Carbon Fiber Front Diffuser
- Euro-Spec M3-GTR-style Carbon Fiber side skirts
- SRS Rear Bumper w/ Ribbed Carbon Fibber Diffuser
- Carbon Fiber M3 Mirrors
- Vorsteiner Carbon Fiber Roof
- Shadowline "Black-Out" Window Trim
- Carbon Fiber OR Black-Out Front Kidney Grills
- Body-Color-painted Body Moldings (the black strips on your car)
- Carbon Fiber Front Brake Ducts
- AC Schnitzer Carbon Fiber Roof Spoiler
- Recaro Pole-Position Racing Seats (Alcantra w/ Carbon Fiber backing) Driver/Passenger
- Rear-Seat Delete (have custom "shelf" made back there; cover with Alcantra)
- Carbon Fiber Center Console
- Recaro 5-Point Racing Harnesses
- TC Kline 5-Point Roll Cage
- 20% Tint all-around
- Strip trunk (remove floor, spare, jack, toolkit, etc)

This will drop about 500-800lbs from your car, the majority of it from above it's "waistline", which is very, very good. The carbon-fiber roof alone will save you close to 100lbs from the highest point in the car (assuming you have a sunroof?), which lowers your center of gravity. The carbon-fiber everywhere can/should be mostly painted, although leaving "hints" of it for every item looks really good (leave the whole roof exposed CF, leave the vents on the hood, the tip of the "spoiler" on the trunk, the whole rear diffuser, the whole front splitters/lip set-up, the whole kidney grills, the center "indent" on the sideskirts, the whole interior center console, the whole rears of the Recaro seats, the whole mirrors, etc, etc).
The interior will lose the 5-people ability, and you'll definitely lose the "sleeper-look" if you install a roll-cage. However, it stiffens up your chassis A LOT, so you should weigh the pro's/con's. I wouldn't do it in a street car, but some people do. I would certainly do the race seats, as they will save almost 100lbs themselves (assuming you have leather/heated/power/memory/etc seats). Those, and the roof, would be the biggest weight saves that are still practical.
Doing these mods will 1) make your car look completely, incredibly badazz, enough to keep up with how incredible of a motor you have 2) they will lower your weight and CoG, which in turn will make your car faster, more fuel efficient, handle MUCH better, and again, put less strain on the engine 3) increase aerodynamics so that the car won't require as much power to overcome air resistance at a given speed, but some parts will also increase downforce, meaning that at-speed, air "Pushes down" on certain areas, increasing handling significantly, as well as your ability to brake AND to "power out" of corners". THERE IS NO "REAL" DOWN-SIDE TO LOSING WEIGHT!

After you do all of these mods, get your car corner-balanced, and run about -2deg Front and -.2.5 to -3.5deg Rear of camber. Try to keep Toe and Caster as "stock" as possible, as they just make your car "skittish" and don't offer any real value for you.

So, you've put $25-40k into your car, and it's a normally-aspirated MONSTER. With all the weight loss, the LSD, the higher gearing, and infinitely more capable suspension, you should be able to knock about half a second off your 1/4 mile time, but inrease the trap speed by probably 10-15mph.

Is it worth it? Yes, and No, depending on if you want to spend this much money to have that unique of a car, that still is NOWHERE NEAR as fast as it would be with a supercharger kit that costs 1/5 the price. It is, however, something that could be "campaigned" in the "Naturally Aspirated - Unlimited Class"-es of many, many race circuits. If that's the case, you'll want to build your bottom-end up to increase compression, and be able to run the motor to 9k rpm and make over 400hp naturally-aspirated. But such things are unrealistic for 99.5% of people on this site.


GOOD LUCK!

[Alphatek45]

Great info, Eli. Thanks for sharing!

[Marcus-SanDiego]

Most of you have probably read this thread that I frequently post from E46Fanatics regarding getting more power for the ZHP. If not, sit down and take your time; it's got a ton of spot-on correct info. This would be the route to go if you didn't want to go with FI (forced induction) from either a turbo or SC (supercharger).

Post #6
http://forum.e46fanatics.com/showthread.php?t=625874


I would have copied and pasted the whole thing here but currently we are limited to 1,000 characters in a single post and that one is over 1,400. Maybe something worth changing Marcus?

Will have the parameters changed.

OK. Check to see if you can post it now. I have allowed for 30,000 characters.

[jjcools]

Eli, you are my friend.

I will keep you in my frequent contacts so that someday when I am rich, I am going to call you and have you help me build up a sweet, unique road demon.

[mimalmo]

LOL, no problem guys.

[thesixsins]

I really liked Turners Take on adding performance to the Performance.

http://www.turnermotorsport.com/html/330.shtml

[jjcools]

Yeah,it sounds like they built a beast that can also commute.

[zhp43867]

For those of you who have a Limited Slip, was/is it worth the money? I don't want to start a war- but what are the best options? I've read about clutch vs geared, Quaife, OS Giken, etc. and I'm lost.

[Marcus-SanDiego]

I can only speak to my 335. It has a Quaife LSD. And it does make the ride more sure. It's worth it to me.

I point and go.

I'm running Dinan Stage II software on it.

[jjcools]

Regarding th rear dif, I read on the E46 site that you may not see a big difference in DD but when driving sprited it really livens up.

[Marcus-SanDiego]

I imagine that's true, JJ. I have 420 ft. lbs. of torque on my 335, so it makes a difference all over the place -- even with daily driving.

You'd get a lot of use out of an LSD on the track with the E46. You'd also notice it when doing sweeps and tight turns on the streets.

[zhp43867]

I notice the lack of a LSD on my car a lot... then again I drive pretty hard.

[jjcools]

I need some money...

[peterbg16]

I need some money...

+100000

[Marcus-SanDiego]

+100000

Ditto.

[Linh]

Did you ever find the info you wanted reguarding the x-pipe?

I too, was thinking about adding one for a more aggressive sound, better performance would be a plus.

One could always delete the 2nd resonators with straight pipes, but from researching around, you would lose bottom end for more top end power.

[jjcools]

No, only clips from you tube.

[INDY|UND3RGROUND]

I wanted to see if anyone has done the 2nd resonator delete. I saw a couple of clips on Youtube with guys that had cut those out and added an x pipe in place. Is the performance exhaust on it really better than the other bmw exhaust?

What is the best bang for the buck performance upgrade for the Zhp? Coilovers? Intake?

Just a question for people that have improved their Zhp, what did you like that you did and what did you regret?


I have so far gotten an AFE Intake, Bimmer Brakes Ceramic Headers, AA Exhaust and all Res. Delete. I'd have to say it's real loud, but I like it that way considering my daily driver is a quiet 08 e500. I also observed a noticeable gain in power, I'm getting AA software soon as well. I know many people say don't do it with the ZHP, but I have talked to Viral from Active Autowerke and it is beneficial when you have mods and they program what mods you have into the software to maximize your performance gains. But for a cheap mod, may I suggest EvoSport, TMS, or ECS engine pulley's? I'm going with TMS.

[Linh]

I have so far gotten an AFE Intake, Bimmer Brakes Ceramic Headers, AA Exhaust and all Res. Delete. I'd have to say it's real loud, but I like it that way considering my daily driver is a quiet 08 e500. I also observed a noticeable gain in power, I'm getting AA software soon as well. I know many people say don't do it with the ZHP, but I have talked to Viral from Active Autowerke and it is beneficial when you have mods and they program what mods you have into the software to maximize your performance gains. But for a cheap mod, may I suggest EvoSport, TMS, or ECS engine pulley's? I'm going with TMS.

How loud is the exhaust with the resonators deleted? Also is it true we have rear and pre-cat resonators? I've heard rear deleted res. And it sounded ok, but resulted in lose of low end torque. Wonder if cutting both the front and rears be better?

BTW I was thinking about installing the uuc under drive pulleys, but what's TMS your thinking about?

[INDY|UND3RGROUND]

How loud is the exhaust with the resonators deleted? Also is it true we have rear and pre-cat resonators? I've heard rear deleted res. And it sounded ok, but resulted in lose of low end torque. Wonder if cutting both the front and rears be better?

BTW I was thinking about installing the uuc under drive pulleys, but what's TMS your thinking about?

It's pretty damn loud haha, and a guy at a BMW tuning shop said I wouldn't be losing any back pressure or HP/TQ.

Here you go, I just like the TMS in my opinion, there is also a dyno chart at the bottom.

http://www.turnermotorsport.com/html/detail.asp?PRODUCT_ID=PPK-E46

[Pooters]

Speaking of Active Autowerke, have you guys read any reviews on there stage 1 super charger? It seems like a pretty nice kit. I'm going to try to FI my car by January of 2011.
http://store.activeautowerke.com/active-autowerke-e46-330-supercharger-kit-level-1-p35.aspx

[Marcus-SanDiego]

Pooters, keep us updated on your progress. Though I do not have plans to throw a blower on my ZHP, I can live vicariously through you.

[mimalmo]

I think I'd just go straight to level 2. It's only $1,800 more.

[Pooters]

Yea, the only problem with stage 2 is that I'm sure it's pretty loud. I want to keep my car "sleepy" I guess you could say. After all, one of the main reason I got my BMW was for the ride quality and interior. As for the kit, it doesn't really look too difficult to install. My brother in law is a mechanic at our local BMW dealership. And he said that the majority of the cars he sees in the shop with an after market super charger are using the Active Autowerke kit. How ever, neither of us have installed a charger before. So that should be tricky.

[mimalmo]

Loud???

I'm pretty sure Level 2 just adds an intercooler.

[Pooters]

^I'm retarded. When I was looking at the display pictures I thought they both just came with oil coolers. Didn't realize until further inspection that the stage 2 comes with an intercooler and the stage 1 doesn't. Disregard my previous statement.

[INDY|UND3RGROUND]

When I purchase the AA supercharger I'm going with stage 2.5

Which includes Water Methanol Injection, and I will also purchase an HKS boost controller

[INDY|UND3RGROUND]

How loud is the exhaust with the resonators deleted? Also is it true we have rear and pre-cat resonators? I've heard rear deleted res. And it sounded ok, but resulted in lose of low end torque. Wonder if cutting both the front and rears be better?

BTW I was thinking about installing the uuc under drive pulleys, but what's TMS your thinking about?

I recently got rid of the Bimmer Brakes headers and bought active autowerkes, and put the two stock resonators back on and it sounds a Lot nicer, no drone at all, and sounds great when I accelerate.

[Dean]

Im looking into ebay headers, unless you can beat their price shipped :shift And what made you change?

[INDY|UND3RGROUND]

Im looking into ebay headers, unless you can beat their price shipped :shift And what made you change?

For some reason my car completely rejected the ebays/bimmerbrakes headers.. My car would misfire and I'd have to pull over and restart my car and 5min later it would misfire again and run really bumpy, slow, and sound just like a diesel tractor, AA's no problem at all. But if you buy from eBay, buy from tradernas, they are pretty damn close to the design of AA headers

[INDY|UND3RGROUND]

I'm getting my top end ported and polished, and I'm also getting shrick race cams, I should be looking at a 50hp-70hp gain in power.

[danewilson77]

ZHP's have shrick cams already.

[kayger12]

I believe the Schrick cams have a different lift and duration than the ZHP cams.

[INDY|UND3RGROUND]

ZHP's have shrick cams already.

I checked up on it a while ago, they are slightly different, the Schrick's are 264/248, and I believe the ZHP cams are 248/256

[danewilson77]

OK. I thought the performance package at ECS....someone could get for their 330 (non zhp), boasted shrick cams and a 10Hp gain...

[INDY|UND3RGROUND]

I'm not to sure, I will have to look into that

[ZHP-FTW]

I'm getting my top end ported and polished, and I'm also getting shrick race cams, I should be looking at a 50hp-70hp gain in power.

Try and do a dyno before and after the port/polish/cams. I'm interested in how much actual Hp can be gained from this. I'm thinking 50hp-70-hp is kind of high but you never know.

[INDY|UND3RGROUND]

I'm fairly skeptical about it being that high as well but I heard it does give you a very noticeable amount of hp and tq. I will most definitely dyno before/after.

[Tony S.]

I wanted to see if anyone has done the 2nd resonator delete. I saw a couple of clips on Youtube with guys that had cut those out and added an x pipe in place. Is the performance exhaust on it really better than the other bmw exhaust?

What is the best bang for the buck performance upgrade for the Zhp? Coilovers? Intake?

Just a question for people that have improved their Zhp, what did you like that you did and what did you regret?

Hands down the best bang for the buck N/A bolt-on upgrade for these cars is a 3.38/3.46 differential. Or a 3.64 if you don't want 6th gear as an overdrive. Figure $150-$300 for a used differential, plus roughly $200-$400 for installing it.

[bullfrogs_M3]

What type of "Up the performance" are we talking about in this thread?

HP/Baseline Engine Performance?
OR
Cornering/Ride/Slalom Performance?

Perhaps we should two threads for this? Each thread similar to the thread about coilovers answering 3-4 questions.

1. What mods have you done?
2. What were the costs? And links to site of purchase
3. Opinion of performance gain/substraction
4. Pics (where applicable).

I am sure everyone has their own opinion and more importantly, wallet, that they want to express. By having two threads we can dive into what some aggressive, mild and stock owners here have done. I noticed some people have done aggressive handling mods, while minimal engine mods and vice versa.

Thoughts?!