JosephIV

iTrader: (14)

Hey guys and gals, I'm purchasing an -01 M6 Z28 and would like opinion on mods. The car is a 35k mile cream puff and only mods are shorty headers, y-pipe, gutted cat and SLP lid. Car has 3.42 gears, stock clutch and catback, and factory Hurst shifter option. I plan on keeping this as a nice driver that can drive in heavy traffic no sweat. What mods make the most sense and in what order? Keep in mind that I will have it dyno tuned and won't be looking for big numbers on the dyno or the track. The stuff I have been looking at is as follows:

Comp Cams XR265 Hi Lift cam - bought it, #'s are similar to LS6 but higher lift.

Patriot Stage 2.5 CNC 5.3 heads - will buy within the week

Comp 1.75 roller rockers - Want but are they necessary or a luxury?

Billet Flywheel - Want, shaves 8lbs rotating mass, goes with new clutch

Clutch - Will get, want stock feel and 500 horse capable

Nitrous - Have NIB NX wet kit sitting around. 50 -75 hp. No purge, heater or blow down yet. Don't want to rag the car out but an extra 75 RWHP at the flick of a switch is nice. Is this overkill and too hard on such a nice car? Should I sell this to fund other mods?

Full BMR suspension - Want. Should I do this first? Is non-adjustable a waste of time?

Koni Adjustable shocks - Will get. Had good experience with Koni.

Lowering springs - I'm on the fence with this. I don't want a lowrider, but the 4x4 stance has to go. My friend's LT1 has Eibach Sports and is a joy to drive. I imagine the LS1 springs feel different. I refuse to cut springs. Suggestions?

Borla Catback - The stock system has to go. Should this be a first mod considering the car has headers already?

Subframe connectors - Coming from Foxbody 'Stangs these cars seem solid to me. However, car has T-tops.

Ignition - Have new MSD 6AL. Worth the effort or sell it?

3.73 gears - Just considering stepping up. 4.10's aren't an option. Is one company's product really noisy, stronger, etc? Want the car to feel and sound like the gears came from the factory.

Tru Trac posi - Replaced stock G80 in my truck and love this setup. Is the stock unit in the F-body capable of handling about 450 horse? After viewing the ring gear carnage in my Silverado I don't want a repeat performance.

Dyno Tune - Will get this after exhaust, heads, and cam. Is LS1 edit still the most used? I don't know what shop will be chosen. Advice for good shops in MD, DC, VA, PA or Delaware?

Sorry for the long post, but I want to buy everything right now but it's not feasable. Please give me your opinions on what you would do to make a well mannered driver and in what order. Again, I'm not shooting for a 10 second track rocket. Just looking to build on this virgin car and put a bigger smile on my face. Let the advice begin! Thanks!

teke184

iTrader: (5)

Comp Cams XR265 Hi Lift cam - bought it, #'s are similar to LS6 but higher lift.
could have done better on that choice. thats a very small cam and for the money, you could have gotten ALOT more power with almost no change in drivability.
Patriot Stage 2.5 CNC 5.3 heads - will buy within the week
with that small cam...hardly worth the money. small cam plus the 220cc runner will give sluggish low end.
Comp 1.75 roller rockers - Want but are they necessary or a luxury?
totally not needed. spend money elsewhere
Billet Flywheel - Want, shaves 8lbs rotating mass, goes with new clutch
not a bad choice
Clutch - Will get, want stock feel and 500 horse capable
i perfer spec...but the textralia clutches have been doing well.
Nitrous - Have NIB NX wet kit sitting around. 50 -75 hp. No purge, heater or blow down yet. Don't want to rag the car out but an extra 75 RWHP at the flick of a switch is nice. Is this overkill and too hard on such a nice car? Should I sell this to fund other mods?
not a bad thing to have...make sure to get all the safety stuff along with it.
Full BMR suspension - Want. Should I do this first? Is non-adjustable a waste of time?
what constitutes "FULL"? most needed to start with....sfc, lca, relocation brackets. things like a torque arm are good, as is the panhard bar and sway bars.
Koni Adjustable shocks - Will get. Had good experience with Koni.
one of the best choices...more on that later
Lowering springs - I'm on the fence with this. I don't want a lowrider, but the 4x4 stance has to go. My friend's LT1 has Eibach Sports and is a joy to drive. I imagine the LS1 springs feel different. I refuse to cut springs. Suggestions?
look up the koni lowering method. you can use stock springs on the lower front perch...for a 3/4" drop. and you can remove the rear spring isolater for a 3/4" drop. small drop so it helps appearance, but not "too much"
Borla Catback - The stock system has to go. Should this be a first mod considering the car has headers already?
borla = $750 cutout. there are MUCH more cost effective catbacks. get one you like and install a $30 cutout right before the axle. i like magnaflow personally. or go true duals.
Subframe connectors - Coming from Foxbody 'Stangs these cars seem solid to me. However, car has T-tops.
very worth while. style doesn't really matter. even the 2 point tubular are a benefit.
Ignition - Have new MSD 6AL. Worth the effort or sell it?
won't install on the "coil per cyliinder" LSx engine...so sell it.
3.73 gears - Just considering stepping up. 4.10's aren't an option. Is one company's product really noisy, stronger, etc? Want the car to feel and sound like the gears came from the factory.
why are 4.10s out? you only gain 300rpms at 75mph with them?
Tru Trac posi - Replaced stock G80 in my truck and love this setup. Is the stock unit in the F-body capable of handling about 450 horse? After viewing the ring gear carnage in my Silverado I don't want a repeat performance.
the stock 10bolt is weak as ****, especially when you put the smaller toothed 3.73 or 4.10s in. guys break them on stock power, some guys get 100's of passes on 450hp...its a crap shoot. honestly save your money for a 12bolt. althogh there are options for strengthening the 10bolt
Dyno Tune - Will get this after exhaust, heads, and cam. Is LS1 edit still the most used? I don't know what shop will be chosen. Advice for good shops in MD, DC, VA, PA or Delaware?
do a local forum search


suggestion....get rid of those shorties in place of some long tubes. with h/c (even small) you'll be choking your car by probably 25hp.

landonew

sell cam, and have one custom ground to your specs, you really want one that is a bit larger than that to take advantage of the heads.

Ths ls7 clutch is a great deal (around $400), and will handle a simple H/C car. I have one in my car, and it is great for DD. It is soft, and is essentially a stock clutch that is meant for a 500hp vehicle (i.e. ls7 corvette).

10 bolt Rear end is junk. I love my 9", but make sure the install is done right. If they don't set the backlash correctly, then it will be loud.

Also, you will want a good set of LTs. The shorties will really choke the car up after the cam. Good news is that you can sell your shorties to offset some of the costs.

That being said, I would suggest you start from the back and work your way forward. If you are doing your own work, then stick the cam in there for now until you are ready to do it right. It will be fun and allow you to enjoy the car during the build process. Here is the way i would do it.

Suspension: BMR is a great choice => . I have all their goodies on my car. You should do the suspension when you do your rear end, otherwise it will be difficult to center it. Everything should be adjustable. You will need a Torque arm, and should get one that mounts to the chassis to take pressure of the trannsmission. This an be done by buying the "extreme duty" or "track pack". Or you could get the adj. one and buy the relocation kit



You will also want LCAs, and a panhard bar. Make sure that you get ADJUSTABLE stuff.

Lowering the car is your choice, but with LT headers you will have clearence issues. Springs, and coil overs should be chosen depending on your application (stiffer = handeling, softer =drag).

Step 1: Rear end + suspension + install cam you already own

Step 2: Heads + Bigger Cam + Clutch + LTs + catback

JosephIV

iTrader: (14)

Yeah, I figured everyone would say go bigger on the cam. I erred on the side of caution 'cause I will be teaching my wife to drive stick, plus the $327 sale price I paid for the new cam was still a shock to the wife. So what would be a decent off-the shelf cam? I could justify about $450 for a custom cam. Is that price reasonable?

I wasn't sure if there was a spot for the MSD. I realize that the car is coil on plug like my truck, but didn't know if there was a harness that you could plug an MSD box to. Too bad, I guess the stock coils will be ok.

The Patriot heads were advertised as a having a smaller runner. I questioned that considering other heads have 200cc or similar runners. I'm used to 5.0 engines where 165 to 185cc fit the bill and 205's were OK for 347 strokers. Would the Edelbrock Performer RPM heads be a better fit?

I should have said that I meant BMR goodies for the rear. Not gonna do K-member or A arms. Torque arm, LCA's, whatever helps hook.

The Borla is a sound/looks issue. I have a friend with the same type of exhaust (shorties, gutted Y) and with the full open Borla it sounds mean as hell. Probably won't sway on this purchase, but will look for used.

I have searched on the forum about parts, it's just hard when you're reading 4 different points being argued by different people as opposed to having someone tell you where you could do better and why it makes sense.

I'm calling dyno shops today. There's one within 45 minutes called Tempest Racing in Waldorf, MD. Primarily a turbo Honda place, I've seen a few 700 to 1200 RWHP turbo Stangs that got built in there. We'll see.

Thank again, I'm still learning such things as Master Cylinder drill mod, Torque arm relocation brackets, and what you can expect from which mods. I look forward to more responses! Will probably send the cam back.....figures!

teke184

iTrader: (5)

a good off the shelf cam would be the 224 cam from either thunder or TSP, or you could easily step up to the 228 cam. both are proven performers and still mild on the street.

ls7 clutch isn't bad, but the weight is brutal...which will rob some power to the wheels. lighter flywheels offset that a bit.

the edelbrock heads are pretty pricey for what you get. if you want to spend that much....go for Trickflow 215s or the AFR 205s. both are capable of serious power and are top quality. make sure to get the compression up since these cars LOVE compression.
on a smaller budget the patriot heads are not BAD....but i think there are better. if you got the 224 cam and the patriot heads, you should comfortably sit at 400rwhp. with the smaller runner heads you may get a bit more torque and maybe a few more hp. but its really hard to say exactly.

the suggestion of the chassis mounted torque arm is questionable. it limits your exhaust options, and i think most subframe connectors. and in all reality...probably overkill for what you want....a street freindly car. if you're worried about the tailshaft mount...there are other options from BMR.

borla...sound...wide open is the same as a cutout. and even closed its very similar to a magnaflow. looks...buy the tips separate. i can't imagine spending 2X the $$$ for an exhaust that is nothing more than a fancy cutout.
personal favorite is by far true duals. 2.5" off the headers, xpipe, and magnaflow 4x9 mufflers dumped. more than enough flow for 500+hp and amazing sound.

JosephIV

iTrader: (14)

Thanks, I'm still green to all of this. It's difficult figuring what will make me happiest.

I cancelled the cam, thankfully it hadn't shipped. Ordered new cam. Specs:
ADV Duration: 275/277
Duration at .050: 222/224
Lift at 1.7:1: .566/.568
Lobe Sep: 112

Yeah, I could still go bigger, but once again this car is going to be a well mannered driver.

I priced Livernois, Patriot, and TSP's offering of CNC heads and will call the shops to hear recommendations. A 200cc runner does make more sense. Plus, I'm looking to spend about $1500. Maybe the Edelbrocks were priced each? I'll have to go back to the website that they were on. Could've sworn it was $1200 a pair assembled.

At this rate is it safe to say that stickier tires might be a better purchase for now until I decide if using the BMR goodies with the 10 bolt is worth it?

I'm so psyched about this car! Can't wait to bang gears and smack some of the local ricers with crappy attitudes!

landonew

If you aren't going to replace the 10 bolt, then just get LCAs for now. The TA should be done when you install the new rear end.

Good choice on the cam. I went a little larger with mine. The exhaust will make a big difference in sound/street-manners, so keep the cats and get a quiet cat back.

If you decide to spring for a better set of heads, you should look at the aftermarket castings (AFR, ETP, TFS). If it is a question of timing, save for the better heads and just run cam only for a while. That cam will make good power, and to be honest you won't have trouble with the majority of cars on the street. The heads are a big decision and investement. It may be hard to justify an extra $1000 for 25hp, but you also have to understand that they have better torque #s too. Not knocking the tsps (great porting job), but for the money you are talking about spending why not spend a little more for a GREAT set of heads.

teke184

iTrader: (5)

good move on the cam...the one you got is a better choice and should make good streetable power.

unless i'm thinking of different edelbrock heads...they're about $2400 for the pair.

all the companies you listed offer great bargain heads that will produce good power. your $1500 budget pretty much eliminates the option for the aftermarket heads.

sticky tires are ALWAYS a good thing. but start running good power or hard launches and you're always gonna increase the chance of blowin the rear. i've been running 400rwhp on my 10bolt with 315 drag radials for 2 yrs...no races really, but i drive it hard on the street. and sofar its OK. i did install a girdle and bearing cap stud kit to strengthen it up.


don't forget the small stuff....pushrods, oil pump, timing chain, gaskets, head bolts..etc.

teke184

iTrader: (5)

i agree with lando

you may only see 10-20hp more peak with GOOD heads...but alot of times its the power under the curve that is big. some guys see 30-40hp more at 3500 or 4000rpm, but small gains at 6000. and generally torque is better with the better heads.

another good thing about waiting on heads...is you'll get use to drving the car. all the power in the world is great for bragging...but its the one that drives the power they have to its potential that will win on the street.

JosephIV

iTrader: (14)

The points you guys have make sense. It's hard balancing the "I want it now" feeling with the sensible "save now, buy bigger, better later" approach.

I guess one of the biggest limitations is my fairly new marriage. The wife is great and greenlighted the car in the first place. She can't see why I should spend money on different heads or dump 2 grand in one month when I'm spending 11 grand on the car.

Everyone has been great. I really like hearing the voice of reason that some members offer. The more I look at exhaust cut outs the more I think I'll end up with one.

Man, will it be hard to hold off on the heads. I understand the power under the curve idea. I'd rather have more torque and hp from 2200 to 6500 than just a higher number at one given point.

I'm gonna purchase the flywheel and research clutches. I can get a flywheel on sale right now from SLP. So longtubes and catback will be first on the power list. I'll get the rest of the NX kit too. I gotta slow down or my baby girl will be without a college fund!

speedshifterNC

iTrader: (1)

bump all of that...I'd go with a supercharger with that low of miles

bad2dbone

iTrader: (37)

Hedas,tru Duals,cam,long Tubes Fuel Pump,injectors,suspension Of Course Dont Forget Springs Maybe Even Nitro.

davered00ss

iTrader: (4)

Different Cam
AFR heads (worth the extra $)
Rockers = waste of $
Tune is a good idea to do early. Retunes are cheap & sometimes free.
Subframe connectors are a must on f-bodies