Author Topic: 355 build for 85 chevy need help  (Read 7917 times)

Offline rick39452

  • Newbie
  • Posts: 7
355 build for 85 chevy need help
« on: August 08, 2010, 09:09:39 PM »
Im building a 355 for my 85 chevy truck I have already ordered a scat rotating assembly and im gonna have it balanced the truck will be drove about 50/50 street and track right now it runs 9.80s in the 1/8th mile with a 350 with 400 heads and a small cam with a turbo 350 lockup with a 2500 stall and 3.08 gears I plan on going with 3.73 gears and a good built non luckup th350 trans I would like to atleast break into the 8s so the question is what heads would be able to do this and my budget is around $1000 for heads

Offline VileZambonie

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 19046
Re: 355 build for 85 chevy need help
« Reply #1 on: August 08, 2010, 09:48:04 PM »
Your wasting your $ on that lower end. For what you spent you could build a 383, vortec heads, ditch the th350 and go with a 700R4, and a 3.73 lsd
,                           ___ 
                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline screamin86

  • Junior Member
  • ***
  • Posts: 661
Re: 355 build for 85 chevy need help
« Reply #2 on: August 08, 2010, 10:19:28 PM »
you should buy my scat stroker crank and forged scat rods :p
86 k10 lwb 4x4:350 .040 214/224 444/466 112lsa performer rpm 1406 lt's summit racing th350 2800stall
03 yukon xl:tint debadge full boltons
86 ta:lm7 hot cam boltons

Offline rick39452

  • Newbie
  • Posts: 7
Re: 355 build for 85 chevy need help
« Reply #3 on: August 09, 2010, 09:39:58 AM »
the reason i didnt do the 383 is cause it would of cost me twice as much so all i ask is if you can answer my question then i would appreciate it if you cant then just dont post

Offline eventhorizon66

  • Senior Member
  • ****
  • Posts: 1910
Re: 355 build for 85 chevy need help
« Reply #4 on: August 09, 2010, 11:57:18 AM »
It is hard to say with no other information on your engine.  Are you shooting for high rpms with that rotating assembly?  What are your horsepower goals?  How much compression do you want?  What cam are you running?

Dart, EQ, RHS 180cc heads will support 450+ hp in a 350.  Of these three, RHS heads tend to be offered for the best price.

Flatlander Racing (http://www.flatlanderracing.com/) has the best price on these heads, that I'm aware of.  A pair assembled with flat tappet cam springs will run about $860 plus shipping.

On an even tighter budget, GM vortec heads with ported exhaust will support 400-450 hp on a 350.  This would also be the better choice if your intention is to keep that "small cam" (depends on your definition of small cam).  Vortecs make big power with not much lift.

Vile is right, though, if you are buying a complete new rotating assembly, a 383 rebuild should cost about the same as a 350 rebuild.  That's why the 383 is so popular.  If your engine builder is telling you it'll cost twice as much, then I'd find a new builder.
« Last Edit: August 09, 2010, 11:59:56 AM by eventhorizon66 »
'85 C10 SWB 350 700R4 TKO600

Offline rick39452

  • Newbie
  • Posts: 7
Re: 355 build for 85 chevy need help
« Reply #5 on: August 09, 2010, 09:49:11 PM »
well i already bought the kit and this is my first build thats why im just doing the 355 as far as the motor it will run on pump gas and the cam will be in the 500 lift range but not sure on the rest of the specs yet

Offline team39763

  • Senior Member
  • ****
  • Posts: 1194
Re: 355 build for 85 chevy need help
« Reply #6 on: August 09, 2010, 11:18:46 PM »
Get a good converter and some sticky tires...that'll shave a bunch of time off your ET's.  As for the heads, I think any decent aluminum head will get you in the 8's(as long as it doesn't give you crap compression).  I've actually been hearing good things about the RHS 200cc iron heads though.

Offline eventhorizon66

  • Senior Member
  • ****
  • Posts: 1910
Re: 355 build for 85 chevy need help
« Reply #7 on: August 10, 2010, 11:04:03 AM »
Whatever cam you choose, if your compression is between 9.5:1 and 10.5:1 (which it should be), make sure the cam is timed on a 108 LCA, advanced 4 degrees.  If you run a dual pattern cam use 1.6 rockers on the intake and 1.5 on the exhaust.  1.6:1 rockers will get you to .500" lift even with a fairly small cam.  With the 180cc heads I recommended you should shoot for about .525"+ lift (that should be possible with high ratio rockers and a decent sized high-intensity cam).  It is also recommended that with a more aggressive cam, you have it nitride-hardened (this service is performed by the cam manufacturer and costs about $100, but dramatically extends the life of the cam).  The 200cc heads will be beneficial if you are running well over .550" lift and shooting for 500+ hp.  But you'll be running a solid roller cam at this point.

*The above recommendations are based on my understanding of the writings of David Vizard.

http://www.amazon.com/David-Vizards-Build-Horsepower-Design/dp/1934709174/ref=sr_1_3?ie=UTF8&s=books&qid=1281456050&sr=8-3

http://www.amazon.com/Build-Chevy-Small-Blocks-Budget-Performance/dp/1932494847/ref=sr_1_1?ie=UTF8&s=books&qid=1281456050&sr=8-1

team39763 brings up a very important point though, the engine is only part of the battle.  Another question would be: are you running a traction aid?
« Last Edit: August 10, 2010, 11:13:27 AM by eventhorizon66 »
'85 C10 SWB 350 700R4 TKO600

Offline screamin86

  • Junior Member
  • ***
  • Posts: 661
Re: 355 build for 85 chevy need help
« Reply #8 on: August 10, 2010, 04:43:39 PM »
Imo get the converter built to the engine specs!
86 k10 lwb 4x4:350 .040 214/224 444/466 112lsa performer rpm 1406 lt's summit racing th350 2800stall
03 yukon xl:tint debadge full boltons
86 ta:lm7 hot cam boltons

Offline rick39452

  • Newbie
  • Posts: 7
Re: 355 build for 85 chevy need help
« Reply #9 on: August 10, 2010, 07:16:31 PM »
no havnt thought about traction yet just trying to get everything else sorted out first

Offline team39763

  • Senior Member
  • ****
  • Posts: 1194
Re: 355 build for 85 chevy need help
« Reply #10 on: August 11, 2010, 02:14:01 PM »
If it were me, I'd cut about $340 out of the cylinder heads budget and buy some caltracs. 

Offline eventhorizon66

  • Senior Member
  • ****
  • Posts: 1910
Re: 355 build for 85 chevy need help
« Reply #11 on: August 11, 2010, 02:35:18 PM »
If it were me, I'd cut about $340 out of the cylinder heads budget and buy some caltracs. 

Good suggestion.  That price is about the difference between RHS heads and GM vortecs.  And we're talking about maybe 20-40 hp difference (with corresponding cam selection).  All this extra power isn't gonna cut your ET if you can't launch hard.
'85 C10 SWB 350 700R4 TKO600