Tech / General Engine Is your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
Sponsored by:
Sponsored by: CARiD

performance cylinder head quesion

Thread Tools
 
Search this Thread
 
Old May 16, 2013 | 04:24 PM
  #1  
UnderCover89TBI's Avatar
Thread Starter
Supreme Member
iTrader: (25)
 
Joined: Feb 2006
Posts: 7,260
Likes: 5
From: Manteca,California. Nor Cal.
Car: SOLD IT. Mopar guy only now.
Engine: gone
Transmission: gone
Axle/Gears: gone
performance cylinder head quesion

a cnc combustion chamber vs non cnc is it really worth the extra money on a street engine for the cnc chamber? what are peoples opinion do you pick up horsepower with the cnc and are we talking signifigant or minimal?
Reply
Old May 16, 2013 | 04:25 PM
  #2  
UnderCover89TBI's Avatar
Thread Starter
Supreme Member
iTrader: (25)
 
Joined: Feb 2006
Posts: 7,260
Likes: 5
From: Manteca,California. Nor Cal.
Car: SOLD IT. Mopar guy only now.
Engine: gone
Transmission: gone
Axle/Gears: gone
Re: performance cylinder head quesion

Originally Posted by UnderCover89TBI
a cnc combustion chamber vs non cnc is it really worth the extra money on a street engine for the cnc chamber? what are peoples opinion do you pick up horsepower with the cnc and are we talking signifigant or minimal?
mod can you move this to power adder section I think it'd be better suited there. my bad.
Reply
Old May 16, 2013 | 04:49 PM
  #3  
ASE doc's Avatar
Supreme Member
 
Joined: Apr 2010
Posts: 4,337
Likes: 29
From: Aurora, OR
Car: 87 IROC Z28
Engine: 355 cid TPI
Transmission: Custom Built 700R4 w/3,500 stall
Axle/Gears: QP fab 9" 3.70 Truetrac
Re: performance cylinder head quesion

CNC chambers are good for a few ponies on a max effort race motor. Key reasons for chamber clean up is preventing hot spots for detonation resistance and to improve mixture motion for best quench. A machinist may use CNC to match chamber volume as part of blueprinting. Much better ways to spend your money on a hot street motor.

This thread doesn't belong in power adders. Power adders is for nitrous and supercharger questions.

CNC porting is good when you start getting over .500 inch lift numbers. Port work gets you more bang for the buck.
Reply
Old May 16, 2013 | 05:56 PM
  #4  
NagleMac's Avatar
Senior Member
iTrader: (1)
 
Joined: Apr 2011
Posts: 714
Likes: 1
From: Pennsylvania
Car: '91 Camaro RS
Engine: Carb'd 383
Transmission: Built T5
Axle/Gears: 3.73 Posi
Re: performance cylinder head quesion

For a street motor I wouldn't even worry about it. It might give you a few ponies but not anything noticable. Now if you have a lower quality head where the chambers arent very uniform, then i can see getting them cnc'd at a machine shop.
Reply
Old May 16, 2013 | 06:30 PM
  #5  
UnderCover89TBI's Avatar
Thread Starter
Supreme Member
iTrader: (25)
 
Joined: Feb 2006
Posts: 7,260
Likes: 5
From: Manteca,California. Nor Cal.
Car: SOLD IT. Mopar guy only now.
Engine: gone
Transmission: gone
Axle/Gears: gone
Re: performance cylinder head quesion

Originally Posted by NagleMac
For a street motor I wouldn't even worry about it. It might give you a few ponies but not anything noticable. Now if you have a lower quality head where the chambers arent very uniform, then i can see getting them cnc'd at a machine shop.
yeah it is trickflow and just the combustion chambers so we are talking like 300-400 dollar difference for that. didn't think it was worth the money unless trickflows are known for being horrid which i have not read about
Reply
Old May 16, 2013 | 08:05 PM
  #6  
Orr89RocZ's Avatar
Supreme Member
20 Year Member
Liked
Loved
Community Favorite
iTrader: (20)
 
Joined: Sep 2003
Posts: 25,895
Likes: 429
From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: performance cylinder head quesion

If you wanted to you can clean up the chambers yourself. Unshroud valve if necessary, clean up the bowl where the seats were cut. For trickflow i would never spend 300-400 on cnc chamber option. Id put that towards better valve springs and or custom cam to extract what i can out the heads. Or mild hand clean up port work to the as cast casting, as a good porter can get nice gains with minimal work

Depends tho on the motor. 375 crank hp build doesnt really need a trickflow 195 casting. A 500 hp one would benefit with mild work
Reply
Old May 17, 2013 | 01:04 AM
  #7  
NagleMac's Avatar
Senior Member
iTrader: (1)
 
Joined: Apr 2011
Posts: 714
Likes: 1
From: Pennsylvania
Car: '91 Camaro RS
Engine: Carb'd 383
Transmission: Built T5
Axle/Gears: 3.73 Posi
Re: performance cylinder head quesion

Originally Posted by UnderCover89TBI
yeah it is trickflow and just the combustion chambers so we are talking like 300-400 dollar difference for that. didn't think it was worth the money unless trickflows are known for being horrid which i have not read about
I just bought some trickflow super 23s with the 62cc non-CNC'd chambers, and they look like a VERY quality piece.

Check it out undercover:

https://www.thirdgen.org/forums/engi...383-build.html
Reply
Old May 17, 2013 | 01:30 AM
  #8  
UnderCover89TBI's Avatar
Thread Starter
Supreme Member
iTrader: (25)
 
Joined: Feb 2006
Posts: 7,260
Likes: 5
From: Manteca,California. Nor Cal.
Car: SOLD IT. Mopar guy only now.
Engine: gone
Transmission: gone
Axle/Gears: gone
Re: performance cylinder head quesion

So 195s are too big for a 'mild' build? That's what I was kind of on. But they don't offer 180cc anymore...I could get some used twisted wedge 180cc but I bought used heads before and I kind of don't wanna go that route. This is also my daily driver for now so it is a lil rough to pick a proper combo
Reply
Old May 17, 2013 | 01:37 AM
  #9  
NagleMac's Avatar
Senior Member
iTrader: (1)
 
Joined: Apr 2011
Posts: 714
Likes: 1
From: Pennsylvania
Car: '91 Camaro RS
Engine: Carb'd 383
Transmission: Built T5
Axle/Gears: 3.73 Posi
Re: performance cylinder head quesion

If youre still rocking a 305 they might be a little big, but i dont see a problem with that, i dont think it'll hurt anything, youre just not using them to full potential. 195s were a conservative pick for my build, mostly based on price and the fact that i want a lower powerband with a lot of torque, not really a high reving ponypower beast
Reply
Old May 17, 2013 | 07:18 AM
  #10  
Orr89RocZ's Avatar
Supreme Member
20 Year Member
Liked
Loved
Community Favorite
iTrader: (20)
 
Joined: Sep 2003
Posts: 25,895
Likes: 429
From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: performance cylinder head quesion

I wouldnt put the 2.02" valve 195's on a 305. It wont fit the valve. Need the smaller 175 cc casting for 1.94" valves

And you can use a small cam large head combo just fine for milder hp setups. Its not considered optimal but does work well sometimes. Guys use 195 heads from all the major manufacturers on all kinds of 350 builds from 300 whp to 450 whp.
Reply
Old May 17, 2013 | 10:01 AM
  #11  
NagleMac's Avatar
Senior Member
iTrader: (1)
 
Joined: Apr 2011
Posts: 714
Likes: 1
From: Pennsylvania
Car: '91 Camaro RS
Engine: Carb'd 383
Transmission: Built T5
Axle/Gears: 3.73 Posi
Re: performance cylinder head quesion

Good point, i didnt even think of valve size. Maybe look at some jegs or summit brand heads? Theyre supposed to be decent quality
Reply
Old May 17, 2013 | 10:57 AM
  #12  
UnderCover89TBI's Avatar
Thread Starter
Supreme Member
iTrader: (25)
 
Joined: Feb 2006
Posts: 7,260
Likes: 5
From: Manteca,California. Nor Cal.
Car: SOLD IT. Mopar guy only now.
Engine: gone
Transmission: gone
Axle/Gears: gone
Re: performance cylinder head quesion

Originally Posted by NagleMac
Good point, i didnt even think of valve size. Maybe look at some jegs or summit brand heads? Theyre supposed to be decent quality
it'd be on a 355 not a 305
Reply
Old May 17, 2013 | 11:00 AM
  #13  
UnderCover89TBI's Avatar
Thread Starter
Supreme Member
iTrader: (25)
 
Joined: Feb 2006
Posts: 7,260
Likes: 5
From: Manteca,California. Nor Cal.
Car: SOLD IT. Mopar guy only now.
Engine: gone
Transmission: gone
Axle/Gears: gone
Re: performance cylinder head quesion

I feel alright about buying the 195 trickflows now. Then later if I decide to go 383 I will have heads that can feed it too.
Reply
Old May 17, 2013 | 11:39 AM
  #14  
NagleMac's Avatar
Senior Member
iTrader: (1)
 
Joined: Apr 2011
Posts: 714
Likes: 1
From: Pennsylvania
Car: '91 Camaro RS
Engine: Carb'd 383
Transmission: Built T5
Axle/Gears: 3.73 Posi
Re: performance cylinder head quesion

Oh then those will be a pretty good head to put on the 355. Like i said, 195s are a more conservative choice for me, I could have run 210s with 1.6 rockers and got much better results, but price was a big factor. I think youll be happy with those heads on a 355
Reply
Old May 17, 2013 | 11:45 AM
  #15  
Orr89RocZ's Avatar
Supreme Member
20 Year Member
Liked
Loved
Community Favorite
iTrader: (20)
 
Joined: Sep 2003
Posts: 25,895
Likes: 429
From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: performance cylinder head quesion

All depends on your rpm and power goals. 400 whp seems popular around here for a target. A good 195cc head will get there on typical 350-383 builds. 6500 rpm. You want much more of either rpm and or power, need to start thinking bigger area ports
Reply
Old May 17, 2013 | 02:39 PM
  #16  
UnderCover89TBI's Avatar
Thread Starter
Supreme Member
iTrader: (25)
 
Joined: Feb 2006
Posts: 7,260
Likes: 5
From: Manteca,California. Nor Cal.
Car: SOLD IT. Mopar guy only now.
Engine: gone
Transmission: gone
Axle/Gears: gone
Re: performance cylinder head quesion

Originally Posted by Orr89RocZ
All depends on your rpm and power goals. 400 whp seems popular around here for a target. A good 195cc head will get there on typical 350-383 builds. 6500 rpm. You want much more of either rpm and or power, need to start thinking bigger area ports
yeah that is where I am at. sounds good. i feel good about the 195s now
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Chuck84TA
Engine/Drivetrain/Suspension Parts for Sale
10
Jul 15, 2016 09:05 PM
gta90
TPI
40
Sep 15, 2015 04:00 PM
NinjaNife
Tech / General Engine
27
Aug 23, 2015 11:49 AM
Randomtask2
Body
7
Aug 13, 2015 01:57 AM
89mulletbird
Southern California Area
0
Aug 10, 2015 10:16 AM




All times are GMT -5. The time now is 05:18 PM.