Whats going on guys, i read quite a bit of these forums and i guess now its my turn to be the one asking a question. I'm looking into a new set up for my next build and would like some input from the experts. I know that a lot of people will basically say "go big or go home", but im trying to stay with what i currently have and just open up the potential that i know it has by using upgrades. At the moment i'm running a basically stock LM7 with a P1SC1 procharger. I say basically because i've changed the valve train and, cam. I'm also running a 4l60e upgraded (with a 4l80e for a back up, lol) and posi 4.10. All this is in a 95' Chevy 1500.
This isn't bad but i know that it could be so much better. It's currently at 440hp pushing 6lbs. My plans are to take the LM7 and punch it out to a 383ci, forged bottom, stay within the pump gas ratio add a set of Trick Flow 215cc heads, use the 90mm Holley High rise EFI intake and slap my P1 back on it. Thats where my list ends.. I'd like to get some input on brands for rotating assembly. (Mid price range) What do you guys think on the head choice and most importantly cam... What cam should i use? I've been looking at Comp Cams XFI series but not sure which one would be best for my application Thanks in advance!

 

Before you start replacing things, just increase the boost. The increase in power you would get from a $2500 stroker shortblock could be done with 4 more PSI. The power gain from expensive Trick Flow heads could be done with another 2.

You could easily increase boost to 12 PSI with no issues, and a pulley change is WAY cheaper than anything else you've mentioned.

You also said you've already changed cam. Which one do you have?

 

Honestly with that setup and a 383 everyone will tell you to overcam but our high lift hot cam will make stellar power and drive easy as well. Has -1* of overlap so boost is still good on it.

Cam springs and pushrods runs $580 but i would recommend either jumping to a pac1219x or dual spring with boost. 1219x upgrade is $620 or duals are $710.

 

I purchased a cam package from local speed shop prior to having the P1 that included COMP CAM.
CAM SPECS--- INT EXH
ADV DUR: 270 278
DUR @ .050 218 223 LOBE SEP: 112.0
VALVE LIFT .598 .571
1915 PUSH RODS 7.400”X.080 WALL
K MOTION VALVE SPRINGS .650
K MOTION STEEL RETAINERS/KEEPERS
UPRGRADED COMP TRUNION KIT

 

The cam isn't horrible.

Get a smaller pulley. Up the boost. When you get to around 12 PSI, see if its any closer to where you want to be.

 

Joe hit the nail on the head. Don't spend a dime changing anything until you up the boost. What are you revving it to?

 

6200rpm

 

And only 6psi? You can run double that and add another 100rwhp without any trouble.

 

what about fuel? Do you think my 255 would be enough for 12 psi?

 

I wouldn't run a 255 with boost on an LS ever. Cutting it too close on fuel. The 255 might carry you to 525-550 HP under the right circumstances. There are lots of larger pumps that are a direct drop-in replacement for a 255.

 

Afr is key as well as fuel line size and whether you are running a hotwire kit or not also. The 255 works well but does have limits

Really depends on how OP has fuel system ran.

 

You can do 800hp on a stock style returnless system. Hot wire kit is a must. Either swap to a single 340 intake or add a 2nd 255 for 75 bucks lol.

 

This is in a 95 1500, not an F-body. Hot wire kit may be completely irrelevant.

 

So.... it looks like instead of making a huge leap, i may just need to take a few baby steps.
fuel pump upgrade and a smaller pulley.

 

Bingo. You'd be surprised how much HP you can pickup with some minor changes. Do you have the truck inlet on the p1?

 

No, just a K&N filter.

 

In nearly any stock setup a hotwire is necessary. esp from a 95 tbi/vortec system

800 on returnless is beyond ok for fbody.

 

I may need to do some research on this hot wire situation. I've never heard of it till today. Could someone brief me?

 

Hardly. It's been done a ton of times, boosted and dry nitrous setups. Not going to argue the point as it's well proven.

 

Cliff notes....all the hot wire kit means is that you run a dedicated thicker gauge wire directly from the alternator usually back to a relay at the fuel pump instead of using the stock small gauge wiring. The fuel pumps will support more hp if you feed them more voltage, so run a wire directly to the pump.