roadan

I have a stock 99 Z-28 convertible with 110K miles. I have started a restoration. I would like to make between 425-450 RWHP on pump gas. I have been doing my home work but the locals tell me I will have problems making that kind of HP on pump gas but I live in a pretty small community. I would like to prove them wrong. Its been suggested I go to an LS6 and w/ possible h/c upgrades plus bolt-ons to get what I want or a 383 stroker plus heads. The more people I ask the more opinions I get. I have been reading the threads in this website for weeks. My girfriend probibily thinks I have a pen pal but I am driven to get what I am looking for. Please tell me more about compression limits for pump gas as well, what CNC porting and polishing heads does for the money and is it really nessesary for what I need. I want this to be a weekend only car with a great lope and RELIABLE. I have more money than knowledge and am by no means a gear head. Please help!!!

Lithium

iTrader: (47)

A decent sized cam and heads will get you there no problem.

mike c.

iTrader: (1)

heads(AFR 205CC)cam(LG-g5x2 or x3) long tube headers(kooks 1/78)mass air,lsx intake w/90mm th-body,asp pullies,30lbs injectors. that w/a good tune will get you 455-465hp on a mustang dyno. 475-485hp on a dyno jet. this is my set up,but i don't have the lsx intake w/90mm th-body, that will come next spring. my car runs 11.1 motor @ 124mph m6 car w/4.11's stock weight. next spring i should run 10.8-10.9 stock weight. i also went 10.1 @ 134mph on a 150 shot too. goodluck to ya.

slt200mph

iTrader: (42)

Bolt ons, heads, and a good size cam will get there with no problem on pump gas.

davered00ss

iTrader: (4)

Heads/Cam bolt ons will get you that rwhp.

LSUxBlake

iTrader: (3)

Yep, heads and cam is all it takes. I made 455 with the setup in my sig.

roadan

Ok, A few of you have recommended a cam and heads with headers and some bolt-ons to flow more air. Specifically which heads and cam, as I am looking for power in the 2500-5000rpm range with a decent lope (please keep in mind reliability)? One of you have also recommended AFR 205's which are pretty new to the arena and spendy. I understand DART and will be making a head and PATRIOT allready does. Can I get what I want from having my LS! heads worked? What would I get from CNC'ing and porting these heads potentially? I understand decking a head may not be a good idea. Is compression only effected by pistons, crank and a potential head decking a guy might do to increase compression. I guess I should havea cmpression test done to see if I can use this engine at 110K miles or start fresh. ?

SAM98WS6

Forget about your heads on a 346...not realistically..unless you find a great porter. Lots of power to be gained with AFR etc....

383s are nice...Mine makes 480rwhp...11:1...92 octane...with ease...steel drivshaft..moser..and Im only using good LS1 heads..those Shafiroff Ultrastreet 383s longblocks are around $5k...from my experience..if you can buy a good engine complete you will be way ahead. 402 LS2s are great too...500rwhp on pump gas is doable with strokers..

santiago

iTrader: (28)

yup I agree with the other guys, you can keep your stock cubic inches and do some milled heads and agressive cam like alot of us are doin.
afr 205 milled to around 61cc and g5x3 cam or cam of that same size. you might even make more that 450rwhp with the right bolt ons.

good luck

98Z28MASS

iTrader: (6)

If your stock short block is good then like everyone said good sized cam and heads will get you there with a good tune and all the bolt-ons. If you want to go a little cheaper than AFR's there are some good 5.3 liter head brands out there so that is another option. Should easily see 425+ rwhp with a fast 90/90 intake/TB combo. Good luck with the build and let us know what you choose!

jester177

if all you are looking for is 450 hp why not do bolt ons, cam and nitrous? That would easily put you where you want to be, thats what i am doing at least. Just my .02

Pipelayaz

iTrader: (2)

Curious to know who makes a really good 383 stroker kit and what else I would need that would compliment the 383 engine wise. I imagine some LS6 heads with a cam and the FAST 90/90. I would like to turbo the car sometime after the install of the 383. I've been searching and reading... any more info would be great. Thanks.

Hennytime

iTrader: (33)

thats what i plan on doing, hotcam and springs are going in in a few weeks, then its n2o time

Katech_Jason

iTrader: (19)

I'd recommend doing a compression test to start. If compression is good I'd say go with:

LS1 Stage I CNC ported heads with lightweight valves - $1799
K-series cam (aggressive yet streetable) - $389.95
LS6 manifold - $450.36
Ported throttle body - $155.00 with exchange
Blueprinted oil pump - $155.00
Heavy duty timing chain - $139.94

all these items are in stock


Other items recommended:
Headers of your choice
exhaust system of your choice