[jlwdvm]

I thought about buying an LS3 or something similar to put in my 69 Firebird project. About $10,000 for a new 480hp version (I know I could get one from a salvage yard, but who knows what you are getting). Then there's the install kit, headers, fuel system, etc. The car already has a new Pypes 2.5" system with Hedman headers, new fuel system, etc. I'm looking to make it into a road race themed car. It came with a "rebuilt" '73 455 with 6X-8 heads. Give me a recipe for 500 hp as far as cam, head work, crank and rods, intake, etc. It will have a 5-speed behind it as well as a 8.5 rear with around a 3.42-3.73 gear.

[Evil Stu]

See sig.

Lots of guys here with good combos: many prefer a roller cam; given the situation with the oils today the roller is one less thing to worry about.

Idles smoothly with a nice lope, drive it anywhere, anytime. No issues with the auto or brakes ~ 11" Hg at idle.

Stu

[Tim john]

Absolutely call SD Performance (Dave & or Marcel) for their input and your goals will be obtained for a well thought out, robust power plant. One that will exceed your expectations and driving pleasure.

Tim john---

[Ollie]

Start by reading the stickeys at the top of this forum. Then get some of the recommend books listed. Especially "How to Build Max-Performance Pontiac V8's by Jim Hand.

In the back of Jim's book, there are 3 or 4 proven engine combination's for different power levels. From several well known Pontiac engine builders.

[jlwdvm]

Been there, done that. Read Hand's book, etc.

[HWYSTR455]

Real easy to get carried away with this, so you need to pick a target goal first (and stick to the plan). So many ways to do it that it's almost not worth trying to answer the question. E-heads and a roller cam would be on that list though (or your choice of aluminum heads).

What's the bottom end like? Questionable? Stroke it.

The rear end is a weak link, that's gotta go too. And don't need that much gear with torque and an overdrive on a 'road race' car.

Pick a target cash pool amount too, that should narrow the choices some.


.

[jlwdvm]

I don't know much about the internals of the motor. It was gone through by the previous owner, bored 30 over, summit 2802 cam, all I know. Lets say $5000 as a budget (for the motor). The machine work and assembly will be done by the shop that built the 400 for my 67 firebird (did a good job).

Road race "themed" to give the look of a a late 60's -70 Trans Am racer. Will be driven on the street.

[HWYSTR455]

5k can burn up real quick on an engine. Maybe limit the mods to the engine and use some on the rest of the car, getting it ready for more power in the future. If you feel ok with the bottom end, a set of e-heads, cam, and related items would be a major improvement, and most could be used on the 'next' engine too. A quick inspection could give you some insight as to the condition of the bottom end.

Roughly:

310 E-heads, setup - @$2600.00
Cam, Lifters - @$250 for Flat Tappet, @$750
Intake - RPM wMod - @$280, Hurricane-@$200, X-Wind @$200
Carb - HP850-@$500, HP950-@$800, Maybe an Avenger 870-@$400


Spring, Front & Rear - @$500 - $1000 (depends on leafs)
Suspension Rebuild - @$600 (Depends on condition and options)
Rear End - @$2500 (Depends on options)

And these are ROUGH GUESS-timates.


.

[jlwdvm]

Yes, I'm trying to figure out where to spend money right now. I have everything to get the paint done (haven't bought base and clear yet) including sandpaper, masking paper, primer from southern polyurethanes, filler, etc (steel work is already done). Just trying to get some ideas in case I decide to tackle the motor this winter. Probably go with tubular control arms in front, stay with leafs in back, solid body mounts, larger disc brake at all corners, and 17/18" wheels and tires.

[HWYSTR455]

Good plan. Get the chassis setup, and all the 'support' systems, and it will handle any power you throw at it. Nothing wrong with leafs, I swear by them, and the GW CAT5 setup rocks. That, with the AFX spindles, which gives you big brakes, and a well-planned 'system, and you will not believe how enjoyable the car is to drive. Sounds like you're on the right track, keep posting!

Maybe get everything else in order, and save for that 'killer' engine. Even if it takes you 3 years, once you get the platform ironed out, you're golden. Even if you have to cruise on a junkyard engine(s), in the long run, you'll be ahead of the game.

.

[ta man]

There are many 500hp combos out there.Its all a matter of budget and how well you want the bottom end built.

[MrPushrod]

Read Hand's book.
Also, depending on what you want to do I think a wrecked z06 is an idea.

[Cliff R]

We just tested a set of 260 cfm CNC ported iron heads from Dave at SD Performance. He sent us the heads, and one of his HR camshafts. It's around 246/256/112, nearly as I can remember, with .400" lobes.

They were installed on a 455 with cast rods and TRW forged pistons and a 247/254/108 flat cam.

The engine resides in a good friends 69 Firebird. The best it ever went prior to the head/cam swap was 12.20's at 112mph.

At Norwalk earlier this month he went 11.60's at 117mph. I'd say it's making a solid 500hp!......Cliff

[MrPushrod]

You're doing a car for the road, do an ls. A c5 z06 gets 29mpg highway. That would be a great maintenance free car that's a driver.

[rcread]

Originally Posted by MrPushrod

You're doing a car for the road, do an ls. A c5 z06 gets 29mpg highway. That would be a great maintenance free car that's a driver.

I get why someone would want an LS, but there is something way cooler about popping the hood and having real Pontiac power under there.

[gtome]

Agreed......... but FI would be great to have.......as well as the maintance free deal.

[Evil Stu]

Originally Posted by MrPushrod

You're doing a car for the road, do an ls. A c5 z06 gets 29mpg highway. That would be a great maintenance free car that's a driver.

How much less maintenance is there? I know the fluid intervals are longer, long life plugs, etc. Anything else? Honest Q, not a challenge, but I have ~ 9000 miles on mine since March: I don't feel like I live under the hood. I admit you need to put in the time to get the tune on it but once that's done, a 500 hp 455/461 is NOT a high strung, high maintenance motor.


My

Stu

[jlwdvm]

I am trying to figure out if the LS route would be cheaper horsepower? Probably not after you figure in the new fuel system, electronics, headers, cooling system, etc. It would surely get better fuel milage, but I don't intend on driving this thing cross country. Even if it got 10mpg better than the 455 it would take a lot of fill ups to make up the added cost of going to an LS. As far as driveability, it would have a Q-jet on it. Though all the trials and tribulations of dialing in the one on my 400, I have a pretty good idea how to dial one of these in (Thanks to Cliff and this board)! My 400 has a xe274 cam, #62 heads, etc and it will give a nice lopey idle at 850rpm with ported vacuum advance hooked up, or smooth as butter with manifold vacuum.

[Jim Robertson]

From your first post it sounds like you have a rebuilt 455 now. Change heads, intake and cam and you are at your stated 500HP goal. It will be very easy.

Milt's 66 Bonne 4530lbs went 11.80s at 113 at Norwalk with a stock block, crank, rods, heavy TRW piston, well ported 6X heads, ported Performer RPM, solid flat tappet cam and dougs 1-3/4" header. Dyno'd over 600HP. With a slighter milder hydraulic cam it made 505 hp and 565 lb-ft torque. The Bonne ran mid 12s with mild cam...yours probably weighs about 1000lbs less.

Call me at 325 692-5002 after 7:30pm central time and we can discuss.
Jim
www.racev8s.com

[gtome]

I would say look at the stats. An LS engine can go 100k miles plus before you would even need to touch it beside an oil change. If you think you will get that out of an average stock bottom end fairly high hp 455.....your dreaming. Plus what is the redline of an LS and FI....cold starts.....not overheating.....MPG.......trans options...etc...etc...

Would surely cost more initially though.

Sure "some" have had good life and luck with the 455.........but compare that to those who dont.

Just I wouldnt rule it out by any means.

And if you decide to get serious about it I have a friend with an engine/trans/harness from an 02 TA ( IIRC) that he may be willing to part with. Wouldnt be an LS3, but a solid 350/365 and I rode in it just before it was pulled out.