Hey guys I have a 92 with about 120k on it. I know the LT1 will live on for many miles to come. I want more power though. I want a 383, and I want it to produce around the 450-500 hp and torque mark. I am going to a desert again soon and am about to save some more $$$. I just spent most of my last savings on the car and I love it but, I want more out of the engine. So here are a few questions.

1. what specs am I gonna need to hit my mark
2. where should I go to get all the parts needed.
3. how much is it gonna cost me.
4. how much more satisfied are you guys with the 383 compared to the stock, or anything else.
5. Oh, how long is she gonna be sitting in the garage.

Thanks guys all replies are appreciated.

 

Other than the bottom end, you'll need some good heads and a fairly radical cam. The stock heads can be made to flow pretty well and could get you there easily. But if you go with some aftermarket ones, you might be able to use a little less cam, if good driveability is important to you. I don't know if my newest combo will quite hit 450 or not. I won't know until it's dyno-tuned. I rather doubt it but I'm hoping it will be close. I'm more hoping it will approach the 500 lbs.-ft. of torque mark. Depending on how you go about it and if you can do most of it yourself, I'd figure on spending $6K or more, minimum. I've got over $3K just in my new short block and did everything myself except the machine work.

 

All depends on all the other decisions you need to make, heads, cam, headers, Compression. A myriad of ways to go, do some reading on what others have done and make some decisions based on what works and what doesn't.

Where ever they are the most cost effective. Not cheap.

Left nut, right arm.

Most people are quite pleased, no replacement for displacement. However I think the same power can be made without going to the expense and effort of a 383. I'll say it again, HEADS and airflow.

Spend all that money you would have spent on the bottom end on some real good heads and maybe have them professionally ported after that.

If you have the money, most don't, do both and you'll top your estimate.

Twice as long as you expect if you play it by ear. 1 1/2 times as long if you do some planning. As long as you expect if you are completely **** about your planning.

Here's a page for some ideas...

http://www.grandsportregistry.com/dyno.htm

 

ALLT4 has the right idea, in that the 'top-end' of your engine (heads, cam, induction) is where most of your power is derived from. Keep this in mind and don't cut corners here just so you can afford nice, forged 383 'bottom-end' rotating components.
You could certainly make 450hp with a 350, using excellent heads and a very healthy cam. 500hp with a well planned 383 should also not be much of a problem, as long as you don't have any emissions/inspection concerns.
Once you start shooting for 500 naturally aspirated horsepower, it gets pretty expensive. This is because you will probably be replacing just about every major engine component with one that is more capable, from the aftermarket. You can obviously reuse your LT1 block, oil pan, valve covers, front cover, and Opti (if it is not very old). You can also reuse your LT1 heads, but they would need a decent port job (and possibly new, bigger valves) that could cost well over $1,000. Everything else needs to be replaced with QUALITY forged parts, high strength fasteners, and specifically designed components for making power as well as lasting a long time. The bottom line is that if you want serious power, you want to do it the right way, and you only want to do it ONCE, then plan on spending more money than you anticipated when you first decided to modify the car.

 

you guys are awesome thanks for all the info. I figured the price would run me around 6k or so. I plan on doing most of the work myself. I know a few things about this stuff but, I have alot to learn. I have quite a while to plan this out to, so hopefully she won't sit there too long. I am sure I will be asking plenty more questions too. I am open to some suggestions to if you have any. Thanks again.

 

Here is a list of parts, with some general specs, and 'ballpark' prices to give you an idea of what to expect.

TOP-END PARTS for 450-470hp LT1 350 OR 480-500hp 383 stroker:
1) 195cc or 210cc AFR heads (LT4), OR ported LT1/LT4 heads that flow around 270-290 cfm (intake) in the .550"-.600" lift range, and around 190-210 cfm (exhaust) in the .550"-.600" lift range. The AFRs should be close to these specs right out of the box. This will be your most expensive single purchase--$1,200 to $1,900.
2) 58mm throttle body, preferably billet--$300 to $500.
3) 1.5 or 1.6 roller rocker arms--$250 to $300.
4) Specific/custom length hardened pushrods--$100 to $130.
5) Hydraulic roller camshaft with .050" durations in the 230s, gross lifts over .570", and a LSA between 110 and 113. Example: 234/238 @ .050" duration, .585"/.585" lift with 1.5 rockers, 112 LSA. Preferably a custom grind--$250 to $400.
6) Heavy duty timing chain set--$80 to $400.
7) .029" or .039" headgaskets--$60 to $80.
8) ARP headbolts--$50
9) 26lb to 30lb injectors--$220 to $300.
10) Adjustable fuel pressure regulator--$75 to $125.

We will assume that the heads will come with the appropriate valves and valvesprings for the intended engine/cam combo. Other things to consider, however, are...using an electric water pump ($200, but allows you to use the $80 timing set), buying Crane or Comp lifters as improvements over the stock ones ($275 to $400), and porting the LT1 intake or getting an LT4 intake to match whichever heads are used.

BOTTOM-END PARTS for building a dependable 383 LT1 stroker:
1) Forged 3.75" crank w/one piece rear main seal--$450 to $800.
2) 6.0" forged I-beam connecting rods for floating pins--$220 to $550.
3) Forged pistons (possibly custom made), flattop or dished (depending on heads and compression ratio)--$400 to $650.
4) ARP main studs for 4 bolt block--$50.
5) High volume oil pump (10% to 25%)--$30 to $80.
6) High quality (NOT cheap) piston rings, STD tension--$120 to $250.
7) ARP oil pump drive--$15 to $20.
8) Additional gaskets and hardware, some specific to LT1 engines--($50 to $150).
9) High performance main, rod, and cam bearings--$85 to $250.
10) Machine shop labor and charges, some may not (??) be necessary--Bore and hone $100 to $150, Deck block $50 to $100 (??), Align bore/hone $50 to $150 (??), clearance for stroker $50 to $100, install cam bearings $15 to $40, clean block $25 to $50.
11) Internal balancing of complete rotating assembly--$150 to $450.

Unfortunately this may not be the end...
What transmission do you have? Do you have any aftermarket exhaust components on the car now?

 

What is it with this 383 stuff in the last ten years or so? Seems like everyone and their brother believes if they plug a 383 under their stock stuff they'll be an instant street star.

They spend all this money on forged cranks, forged exotic rods, forged pistons, ARP hardware, maybe even splayed caps. For what? More torque and some more horsepower. Now you've spent all your money on totally bulletproof bottom end that can handle more power than you'll ever throw at it or be able to afford to throw at it.

Whoops, I totally forgot my dinky little LT1 heads can barely feed the 383 effectively. But dam! Now I'm out of money and this 383 isn't at all what I expected. Crap, now I need bigger injectors, I'll just start cruising E-Bay and look for some deals.

Now you're throwing junk on a bottom end that will never live up to it's potential because you started on the wrong end.

I guess I just have a different philosophy when it comes to power, I start with the top (air flow) and then work my way down.

Nothing wrong with freshening up the bottom either. It's cheap while it's running. Bearings are cheap. Costs go up substantially if you spin a rod bearing, or score a main.

For one thing, it's easier, another reason is cost, you're going to wind up buying all those goodies anyway so get 'em now while you can buy them a bit at a time and get more bang for your buck. If you blow your stock bottom end, I doubt it, you were planning a 383 anyway and at that point it's icing on the bottom of the cake.

 

I have the ZF 6 and catback exhaust.

 

Can it be done? Yep! Will it cost you 6K? Well to be honest I'd expect to pay quite a bit more than that...

Honestly, I don't even want to think how much it cost me with the engine and supporting mods such as the cooling system, and suspension, brakes, etc...

I'd guess it cost me around $14000 maybe more...

But that got me roughly 466 RWHP and 431 RWTQ...if you use a 15% (average) drivetrain loss that about 550HP at the crank. And guess what? I'm not quite done yet!! I still have a good 2K more that I'd like to put into it to polish it off...it's a never ending wallet sucking machine!!

 

I have to agree with ZIX. Just ported LT1 heads and cam are not going to make that kind of hp. Go with the 383 and spend a lot of money on new heads and cam plus the other things he mentioned. Is your car worth spending that kind of money? Buy a 5.0 stang for $2500 and get that hp for a lot less money (flame).

 

Again, ALLT4 is placing the emphasis in the most important aspect of an engine buildup. Extra cubic inches don't mean a thing without the fuel and air to feed them. I have always followed this line of thought and employed it when I first modified my car. I spent my money on ported LT4 heads, a big cam, bigger injectors and throttle body, big headers, and the expensive PROM mods to make it all work on top of my stock LT1 shortblock. I was probably making close to 480hp and still waiting for my 350 to tell me it was 'tired'.
I definitely recommend concentrating on the heads, cam, and fuel areas FIRST. The requisite 383 parts are purely secondary for creating a dependable and worthwhile shortblock for taking advantage of a better flowing, powerful 'top-end'.
Use your budget accordingly, and you will have a better chance of reaping the benefits and "getting what you paid for".

 

Thanks for the advise. Although I have I strong dislike for mustangs, except for the classics. Is it worth throwing money into this car? I think so. I don't plan on selling, so I'll get what I put into it if I live to be 100 or so.

 

Do you want 450-500hp at the crank or rear wheels? There is quite a big price difference between the two.

 

At the crank. How much of a difference in price is there?

 

20/20 hindsight...if only I'd known this sooner!!

 

Jay, I think that you would still have gone with the Corvette! The 2 cars that have really thrown me back in the seat are yours and a co-workers 750 rwhp Mustang. Your's felt much more safe.

 

Yeah, but we both know it's all about the driver at that point...

Oh, and I guess we can add another $550 to the price of my engine, I just had to order a new clutch today (SPEC was closed all last week for the 4th of July...I didn't know it was a holiday that lasted all week!)

 

Hey Zix, I think we have the same 'illness". Can we 'write it off' on our tax returns? Or do we have to go see a doctor/therapist first?

 

Whenever I start thinking about the $$$$ that has flown out of my wallet, my therapy is firmly placed in my heavy right foot!! No sense in throwing more money to a shrink!

It could be worse...I'm just still trying to think of how...

 

PROCHARGER P-1SC 8psi,mild cam, and a custom dyno tune.