I'm lookin for little, inexpensive things to do to my 70 to bring its power up maybe 100 hp or so over stock...a friend pointed out the edelbrock performer power package

http://www.edelbrock.com/automotive/chevy_1e.html

and said it's prolly a couple grand...and the gains were only around 50 hp...which makes me curious. it seems such a low gain for the amount of money. I was looking around on Eckler's, figured I could gain roughly 50 hp by switching out the cam and lifters, and sticking on magnum roller tip rocker arms and an underdrive pulley setup (no one's answered my question about that yet!), for around $650, and spend another maybe $1000 or less on a new carb, intake manifold, and electric fan for another maybe 50 hp...so why are the estimated gains for edelbrock's package so darn low, and if I do decide to switch out the cam and lifters, do I need to replace the cylinder heads as well or no?

I'm just lookin to bring the car into the 350-400 hp range and play with it on the strip this summer...see if I want spend a lot more money converting to EFI and twin turbos to run faster times, or if I'll be satisfied leavin it be.

For the kind of numbers you are looking for I would start with a new pair of heads, if the lower part of the motor is still in good shape.
It's not all that much more work than what you would be doing in changing the maniford, and new cam.
With the new heads, cam, manifold and carb you should get the numbers you are looking for. Someone should be able to tell you what heads to get for the least amount of money. There are lots to choose from.
Good luck

Edelbrock makes excellent stuff, but stuff like their valve covers, etc., will do nothing to increase your motor's performance...just increase their profit margin. I'm guessing their horsepower numbers are probably net horsepower, not gross horsepower numbers. Your '70 is rated at gross horsepower...it wasn't until about '72 that manufacturers went to net ratings. That could account for some of the difference you're noticing.

You should certainly go for a new cam and lifters, but will likely need to have your heads ported if you decide to keep the originals, plus have the valve seats hardened if that hasn't already been done. You may want to go to aluminum heads.

The right cam, intake and carb tuned to the camshaft, plus a less restrictive exhaust system can go a long way toward some pretty nice horsepower and torque increases. This can be done without any changes to your motor's bottom end if it's in good shape. If the block needs to be pulled for boring, etc., the dollar investment increases big time.

There's not a thing wrong with Edelbrock stuff...I have an Edelbrock intake on my '78 and am very pleased with it. Their power packages make things easy, but you can certainly pick and choose from different manufacturers and get as good or even better results. You have to decide what you want out of the car and choose parts intelligently. Too many people buy a big carburetor, single-plane intake when they should buy a dual-plane, install a big hi-lift cam and can't understand why all their expensive, high-grade parts run like crap when installed. Mismatching parts is all too often unknowingly done. Call the techs at Summit Racing or Jeg's and they're very well trained and knowledgeable and will make you solid recommendations on what is necessary to make your car do what you want for your budget. Edelbrock and Holley will give you solid advice as well, but will understandably recommend their products. Nothing wrong with that, but don't limit yourself to strictly one parts maker. Why pay the $ for a Crane, Isky or Comp camshaft when a Summit Racing house brand is ground to the same specs and will do the identical job for a lot less money. If a Crane Cam is the only one to do the job you need...fine...buy it and be happy. I'm just saying pick your parts smartly and you can get some great performance increases and not necessarily break the bank doing so.

I just want somethin to provide some decent power at the strip so I can start wading into racing without diving into the deep end first...I'm close with some guys at a performance shop downtown and we developed a plan for turning that car into a 10 second dragger...but the crashes scare me. I wanna just race it slower at first, see if I like it, build some skill, and not spend a whole hell of a lot of money at first. the plan we worked out was around 25 grand. then determine if I want to run 10s, 11s, 12s...or use another car for racing (which in my opinion would be a waste of materials), or what. long as I'm at it, does anyone know the compression on the 70's 350 LT1?

A '70 LT-1 compression ratio is 11:1...it should say so on the console plate if original.

Years ago a friend who built a Chevy II drag racer told me to get your times down to say 13 seconds took so much money. To get your times down to 12.5 seconds took a bit more money. To get down to about 12 seconds took even more money. After that, it took big gobs of money invested in the motor and car for every fraction of a second faster you want to go...lots into building up the motor, more for a rear end that will take the punishment, strengthening the transmission, taking out every last bit of excess weight in the car, a cooling system that can handle the extra heat, etc. It's more than simply increasing horsepower when you build a car for the track. My friend learned that when his Chevy II was taken home on a flatbed at least once when something broke.

By no means am I trying to talk you out of it. Do it and be happy...just plan out what your needs are and build it right from the get-go.

takin too bloody long to plan. the LT1 is 11:1 ratio even in the package that only produced 300 hp?

Are you sure you have a real LT-1? In '70 it was rated at 370 gross horspower. The LT1 (not hyphenated) from the '90's is rated at 300 net horsepower.

The base 300 horsepower engine in 1970 had a 10.25:1 compression ratio. It had a cast iron intake manifold and a Quadrajet carburetor and painted valve covers...the LT-1 had an aluminum intake and Holley carb along with finned aluminum valve covers and solid lifters. The LT-1 only came with a 4-speed manual transmission and was not available with air conditioning.

In '71 the LT-1 was rated at 330 gross horsepower and its last year of '72 was rated at 255 net horsepower.

im confused..

there were three small block engines in 1970

the 350 with 300,350, or 370 hp

ONLY the 370 horse is an LT-1

if you have the 300 horse engine than you dont have an LT-1

I noticed the link you gave for the Edelbrock Power Package is their Performer Power Package...it's their base level package. If you check out their Performer RPM packages, the increases are a good bit more...they include more capable intakes, cam profiles, etc., but are more expensive as well.

okay so...only the 370 hp was the LT-1...what were the others then?