valiant65

I've been watching a few threads related to valvespring issues in boosted engines with a XER-lobe cam.

I have gathered parts for my build:

-4.03 bore x 4.00 stroke eagle
-eagle h-beams 6.125 w/ L19 bolts
-wiseco k396f3 32cc dish ~8.1:1
-patriot 6.0 stgIII heads 72cc w/ patriot extreme springs 155lbs
-swedish "pyramid ring" head gaskets
-cts-v lifters
-somebodys old custom cam from ebay, XE-R 240/242 .609/.610 LSA 116
-comp #1500 adjustable shaft rockers 1.7:1
-victor jr w/ tall elbow and 90mm tb
-trick flow 120 lbs injectors
-ebay water ic 1500cfm
-jp double roller timing set
-homemade ms 1.75 prim headers, 2.5 merge collectors to 2.5 crossover
-S480 w/ racecover and T6 1.32 a/r turbine
Trans is a TH400 w/ brake, converter 9.5" with 3200 stall
Rear is 9" w/ 3.55 gears
28" radials
3080 lbs fairmont wagon
Usage mainly strip, occasionally street
Should have at least 1000 fwhp.

How much should I have seat pressure? Should I buy new HUC-cam or buy new heads which would allow more spring? Please give some opinions?!

Fbodyjunkie06

iTrader: (10)

Looks like a nice build for sure, I'll be interested in seeing how that S480 works. They have a big exhaust side which will be good for a motor with more c.i. like your's, and that 1.32 A/R will love the track.

I think it will be a decently quick spooling and hard pulling turbo for your needs in that light car.

Any reason why you chose a 8.1:1 C.R. though? Is it because you guys can't run leaded race fuel over there and are octane limited?

valiant65

Thanks for comments! The C.R. is quite low. I was aiming to minimum 8.5 (due to our pumpgas) and that's what parts boxes tell, but when you calculate it with real world numbers you come to 8.1...

This is part of my questions, because if I'm going to have valvespring problems anyway, then I could correct also the compression by changing to heads with smaller chamber? Or what would you suggest?

Nitroused383

iTrader: (10)

Do you know what valves you're running and how much they weigh? It might not be a bad idea to run a marine / endurance style lobe. On a hydraulic roller setup you can only run so much spring pressure before you run into problems. Valvetrain stability is far more important than running an agressive lobe profile, especially on a turbo setup. The HUC lobes in particular are really smooth profiles, basically an updated marine lobe with newer tech and possibly better stability.

valiant65

I haven't weighted the valves (heads are still in the boxes) but they are 2.08/1.60 stainless valves.

My biggest concern is that is there enough seat pressure in the patriot extremes anyway? I mean, will those springs be underrated even with milder HUC cam when used with 20-25psi boost?

How do those comp rockers compare to yellaterras weight wise?

Nitroused383

iTrader: (10)

No way in hell will that cam work with those heavy valves and that much boost let alone xer lobes. You're looking at well over 50lbs of back pressure on the exhaust side. I have not read a single thing about those comp rockers. I think you should call patriot because I thought I had read somewhere they don't recommend real high of spring pressure with those heads. The spring pockets are very thin after their cnc work and people have broke through them before. You really should call up someone who knows what they are doing with turbo ls stuff and see what they recommend; Shawn @ VA speed, Speed Inc and Kurt Urban come to mind.

valiant65

Does anyone have experience with Hinson Supercars Rev Kit ?

http://www.hinsonsupercars.com/p-931-rev-kit-ls2.aspx

I think it would be great correction for my budget engine ?

What's the difference between LS1 and LS2 kits?