Okay, so you did mention a Hotcam later on. I would describe these springs as barely adequate. Yes, many use them with no problems. But if you are planning on visiting redline on a regular basis, I'm just more comfortable with something a little better. Now I don't recommended extreme spring pressures, especially with stock valves. This only wastes HP and speeds up wear. And I don't like dual springs unless the lift, RPM, etc. make them necessary. Dual springs create more heat, raising your oil temps. You mentioned driveability and mileage at one point. The Hotcam is hard to beat in this respect for a street cam in this power range, although there are a couple of aftermarket cams of similar specs that folks have had pretty good results with too. Your 350 RWHP target is very doable with a Hotcam or something similar, fully ported stock LT1 castings, long tubes (I'd recommend 1 5/8" primaries for this HP range) and good tuning. 100K miles is not usually a big deal on these engines but definitely perform a leakdown test before installing modified heads. Your dynamic CR is going to go up with a cam and head package so you'll want to know that all cylinders are in very good condition first.

 

I have to agree that 1 5/8" primaries are great for that power range. Keep the low end TQ, and still plenty of breathing room for the top end. Too many guys think that 1 3/4" primaries are always better, without exploring how headers actually work.

Dan

 

Yeah, it's kind of aggravating if you own an LT1 C4. There's only one company building an LTx specific header for these cars w/ the smaller primaries and that's Stainless Works. I guess the others would rather make and sell what people think they want instead of at least offering what actually works best for most applications. I know a guy who was running 10.70s (NA & no nitrous) in a 421 inch C4 and was still using 1 5/8" pipes.

 

I am not going to do any headwork to it at all. I am keeping it a stock as possible. I know if i start really tearing down the motor then I will want to do even more to it and right now I don't have the funds to do that. I was thinking about going to Bret Bauer for a cam but the price of the hotcam is almost unbeatable for me. What springs should I get to replace the ones taht come with the kit???

 

I suggest talking to Bret before you buy a cam. It isnt going to be easy squeezing 350rwhp out of the Hotcam. Bret could get you there more easily, but it will cost a bit more. Youll also need full bolt on's, I am talking E-WP and everything. Some folks with GM847 and CC306's dont break 350rwhp. But then again its just a number. Bret will tell you all you want to know. Its where I am going for a cam to put down 350-360rwhp on stock heads, thats through an auto too.

-Dustin-

 

I already have an electric water pump. Had to replace the stock one when it went out so I went ahead and got an electric one. How about things like a throttle body??

 

I wouldnt do a TB till after the cam or even heads. The money can be much more effective elsewhere.

-Dustin-

 

Mine put down 320 at the wheels on stock tuning through the stock exhaust manifolds - Hotcam only.

 

how hard is a cam swap and are there any write ups on how to do it??? I am still debating if i should do it or not.

 

Shoebox has a good walkthrough. Look him up on this site and go to his tech page. It's a decent amount of work, but doable if you have patience and can keep things CLEAN. Those are the two most important things. Dirt = spun bearings. Lots of guys have had successful cam installs, and a few have had troubles.

Dan

 

tahts the thing with me. i can get the money to do a cam and stuff, and me and my dad could do a cam in about a weekend. however im so scared of some stupid thing happening, or even worse, something happening and idk what wrong. ive seen it so many times, and you cant figure out what the hell is wrong after youve had the whole engine apart. almost makes me wodner if the peace of mind of my 14.1 car is worth it over a maybe high 12 car if im lucky, but a big pain in the ***. idk...lol