99z28Kev

First post, been looking at the forums for awhile but I need some input on a dilemma I am having. Some background, a month ago i bought a 99 z28 with 180k miles for $3000. Already have changed plugs, wires, power steering pump, and rack n pinion. However to get more power i feel either an engine rebuild or swap is necessary with these kind of miles but im not sure.
My question is this, do i:
A) Do the usual heads/cam and boltons
B) Rebuild the engine and throw in a cam and heads
C) Find a 4.8/5.3 engine block and go for a turbo build
Ill try to anticipate some questions you all may have and answer them.
- My goals are a street car since i will drive it to college because i commute and around town(have an extra car so tearing apart an engine no worries).
- My budget is $700 a month i put towards car mods.
- The car holds oil pressure at 40 psi and goes up with revs like normal.
- My goal is 400-450 rwhp.
- Ive already done a lid
- I want the car to be fairly reliable
-Looking to layout a plan so I dont waste money
- Most work will be done by mechanic friend and myself
Id love any feedback you guys have since i am new to all this. Also, reasons why youd go a specific route, which is easiest/cheapeat and possibly what mods/steps youd take to get there. I appreciate any help!

HCI2000SS

iTrader: (2)

Waite...so you have a budget for $700 a month...are you saying you have that much to spend for every month for a period of time or something lol?

garygnu

consider a 383 stroker engine .with some ported heads ,and the right cam you can meet your goals with streetable cam.

mjs1012

iTrader: (36)

If youre budget is $700 a month Id save it all for a year and do a procharger build. Itll drive close to stock until you get into boost and will easily exceed your hp goals.

Or you can hit it with a shot of nitrous and to do it right it wont take long to do with your budget.

99z28Kev

Thanks for the replies. First off i have money saved up and make a decent amount at my job. So to stay living comfortably i budgeted around $700 a month to build it up. As far as the other two options, what do i do about my engine? Its fine as is to either go stroker or slap on a procharger?

mjs1012

iTrader: (36)

IMO with low boost, meth, and a good tune the motor should be alright for a while.

ds98formula

iTrader: (3)

Auto or manual car? I would go ahead and do bolt ons as if your motor pops they can go I the new one. If auto has the trans ever been gone thru? if not I would do that as that is a ton of miles for the Trans. If m6 how is the clutch? With that many miles on the car I would look at all suspension parts to see if you need to upgrade or replace them. After the car is 100% mechanically sound then I would start saving for the heads and cam. Have fun with your new toy it gets expensive fast.

99z28Kev

Forgot to mention, its. M6, clutch feels great previous owner told me it was pretty new. After taking it to a mechanic of mine he said the suspension is fine since yea i was worried about that as well. Only thing is my motor mounts are a bit worn and the passenger sway bar needs tightening or something he said. Thanks for the advice

ds98formula

iTrader: (3)

Change out motor mounts when you do headers.

99z28Kev

Would it be better to do suspension work before anymore power mods? Since she does have a good amount of miles. Any recommendations on an order of mods to go from here? Seems like the idea is work around the engine while saving up to see if any engine problems pop up, then if its all good go with either heads/cam or boost.

ds98formula

iTrader: (3)

I would go suspension, bolt on, then head and cam.

I did mine kinda backwards I did bolt on and cam and now looking at heads and suspension.

Do a compression and leak down test to see how healthy your engine is. If good I would go ahead on the power mods

99z28Kev

Guess i shouldve done that compression test when changing the plugs... Oh well live and learn. Appreciate the help ots kinda exactly what i was thinking would be the smartest route. Any other opinions?

murphinator

iTrader: (2)

buy or build up another engine as a spare while doing bolt ons to enjoy your current engine , as mentioned you can always re use them on the next engine and you may be pleasantly surprised how long it lasts.

I have had many GM engines with well over 200,000 miles that never needed to have a valve cover off including one that had 345,000 when I sold it .
I have a pewter M6 stock internals car right now that is just shy of 240,000 miles -car has most popular bolt ons (headers, no cats , true duals , Lid, LS6 intake , truck coils , sd tune) .The engine/trans/rear are all original never opened (other than seperated for clutch replacement) , car ran 11.9's back when it had 215,000 miles on it.

I have another A4 Z with 173k also stock internals , similar mods to my 6 speed car but stalled auto , ran 12.1 for me this fall with room to improve ,expecting 11's in the spring , also currently the truck I use to haul cars I buy , scrap , drag ,etc... is a 2500hd with 182,000 on it seen other 6.0's go over 300k so i just keep fresh oil in it lol

99z28Kev

Wow yeah that is impressive. Makes me feel more comfortable modding up this engine. She pulls hard as is so i figured its pretty sturdy. Any special route youd recommenddoing mods since youre knowledgable about these high mile engines? I have a lid already and ordered a cutout. Also did you not go for 4.10s due to the possibility of a broken rear end anyways and not wanting to waste money or was there another reason?

murphinator

iTrader: (2)

I wouldnt go lower numerically than 342's on a stick car that is getting modded and may run sticky tires at the track a few times and retaining the 7.5 ring gear rear end , if you must go lower go 373 or 390, 411 ring is pretty thin . Aftermarket rear end is a different story absolutely go for steeper gears!

long tubes, duals, intake manifold (LS6, Fast ,etc..), and tune will make you pretty happy I would think without really changing what your asking the motor to do as long as the the tune keeps miles in mind when setting rpm limits (6100/6200ish max IMO on high miles stock stuff) I also enjoy my raptor shift light to help keep it off the limiter.

I have other cars so when the day comes that my 240k mile engine makes its last rev I have options and can stash the car till I can get to putting another engine in it , for you maybe keep your eyes to your regional forum and buy a spare LS1 theres always someone upgrading ,parting out etc , either a long block or short block for shorter money or a fully dressed engine you can sell all the accesories ,intake etc... off to recoup some of what you spend for it then at least if the worst does happen you are prepared.

Having a ton of miles always adds insult to injury when your car performs well too.

99z28Kev

Very true, outrun a brand new mustang and laugh while you tell em you have 180k miles plus. I think thats a good idea, boltons around the engine and build one on the side as a learning experience since this is my main hobby and im trying to learn more. What track time/hp estimate would you say for having the mods you stated? And any tips on launching? I seem to just spin tires... thank you so much for the help i appreciate it.

murphinator

iTrader: (2)

your going to need some dr's to hook it up , then you need to be conservative with the launch to keep the 7.5 rear in 1 piece lol 3500-3800 or so - it may take a 5k launch a few times but not many lol.

ET will depend a lot on your ability to launch/shift it as well as if the track is prepped decent and the weather is good for racing , up here in the northeast its pretty easy to find density altitudes well below sea level , while other areas that never happens, being vague here because of those variables but 12's unless your racing at 3000 ft altitude on an 80* day or having issues getting the car down the track well

99z28Kev

Slip the clutch or drop it? Cuz even at 2500 seems like the tires spin, unless i may be just putting my foot down too fast after that. Or its the 245/16 tires i have.What kind power to the wheels would i be about? Also dyou know if our cars lose a lot of power over the years from miles and whatnot

Stoner_Banks

Ahhh the key thing is that its a 99!! The 99 was a special year us fbodies because our block can get stretched to a 408 rather than the normal max (396) and I do recommend it because I am n mid process. Of doing so myself.(H/C/I) TB ect... But now suspension came back to bite me n the ***! Haha...but I'm making around 415 to the wheels before stroking her to 408 so u can do whatever u please...
after I go 408 I'm goin fat turbo! LoL

Stoner_Banks

And I also have 245/16 and I spin a bit so you will want to probably getbl some E/T radials or somethin fatter like the older zr1 wheels that are 10in wide so u can throw on good enough tires to hook up