SpeedTalk Store - Opinion Columns

BBC Bowtie heads

General engine tech -- Drag Racing to Circle Track

Moderator: Team

BBC Bowtie heads

Postby GOAT69 » Wed Sep 09, 2009 8:38 am

Looking at building a smallish (440cube) BBC, spec heads are either GM 14044861 W port or the 12363410 later head. Just looking for opinions or preferences to either one & if anyone has worked with these & what kind of flow/power is acheivable & head men for the job. The engine will have around a 4 1/2" bore, single 4 barrel,any help much appreciated thanks.
"better to burnout than to fade away"...Kergan
GOAT69
New Member
New Member
 
Posts: 40
Joined: Mon Jul 06, 2009 4:16 am
Location: AUSTRALIA

GM 861 casting

Postby ALKYAL » Wed Sep 09, 2009 12:45 pm

I dont know about the 2nd P/N .The 861 was a std head we used during the late 1980s and early 1990s. We used them on 475[approx] size engines. Our application required good torque @ 3800 to 5400 RPM. They were WAY TOO BIG in the Int. Port. Spec @ 380ccs Had To putty them uo/down to approx 335 ccs to work. Also the ex seats had to be replaced[very hard] to use TIT. valves The int was also not too compatable with th TIT. valve. The Guides were std GM and had to be sleeved /wish we would have put in stepped [Brodix] style. They sometimes slipped/ also pinned them later on. They are LIGHT castings. That is why we went to the Brodix casting later along with the cnc porting. Also be very careful if you put a JESSEL system on. The inst. sheet from jessel will have you cut the trough TOO deep. They must have thought that stock length valves were all that was used. [you may break thru into the int port roof!!!]
Some people are so stupid that they dont even know it! - by a famous Hillbilly
ALKYAL
Pro
Pro
 
Posts: 310
Joined: Mon Aug 10, 2009 9:11 pm
Location: OHIO

Postby Abbottracingheads » Wed Sep 09, 2009 2:30 pm

Give us some more data on what you are doing with this engine. The Bowtie heads can be made very good, but they are may pop heads, at least the older castings are. It would have to be a high rpm engine also with those heads. If rules dictate those heads I can make them go.
Abbott Racing Heads and Engines
Abbottracingheads
Expert
Expert
 
Posts: 631
Joined: Fri May 18, 2007 5:46 pm
Location: Crane, Texas

Postby GOAT69 » Wed Sep 09, 2009 3:35 pm

Thanks for the replies, great info. The engine will be for a SuperStock application around 15:1comp,must be flat tappet,cast manifold , will be short stroke,ultra light internals ect. 4sp 7.5lbs. thanks again
"better to burnout than to fade away"...Kergan
GOAT69
New Member
New Member
 
Posts: 40
Joined: Mon Jul 06, 2009 4:16 am
Location: AUSTRALIA

BBC

Postby compguy » Thu Sep 10, 2009 2:27 am

A/MS eh?
compguy
Member
Member
 
Posts: 71
Joined: Sat Jan 27, 2007 2:33 am
Location: Sitting down, facing West


Return to Engine Tech

Who is online

Users browsing this forum: Bing [Bot], Exabot [Bot], Google [Bot], mhr144, Seanh832 and 9 guests