thoughts on 351 vs 306

swammi · 02-03-2011, 06:12 AM

what do yall think of a 351w over a slightly built 306 the windsor is a 77 model block with it bored .030 over and a fresh bottom end . the 306 has scat cast crank,a set of some kind of rods looks like summit stage 1 rods and forged speed pro 9.53 to 1 forged flat tops. i will be running procomp 190 heads , comp cams pro magnum roller rockers,performer rpm airgap intake, and a q650 quick fuel carb.any suggestions on a flat tappet cam for a 351w . the setup will be 5 speed . thanks in advance for any help.

BIGDATOWN · 02-03-2011, 07:23 AM

My only thoughts is on the heads that they will be very large for a 306. My opinion is they would work much better on the 351 but you have to change valve springs on the heads for flat tappet/and depending on if it is hydraulic or solid.

coupe · 02-03-2011, 08:25 AM

351W.

The 650 carb will run out of steam, unless it's been worked over.
Change to a roller cam...it's rather inexpensive horsepower.

swammi · 02-03-2011, 11:33 AM

the carb is a q 650 drag carb

SlowJoe · 02-03-2011, 11:40 AM

351w! the carb should be good as long as you dont turn a lot of rpms.

qkjuicedpony · 02-03-2011, 11:48 AM

Run the 351w and do swap to a roller cam. The carb will be fine but may require some fine tuning if you plan on going over 6k rpms.

H8IMPORTS · 02-03-2011, 01:53 PM

351W! 351 all the way! If you could go to a roller cam it would be better but a good hyd flat tappet cam would be ok as well. I had a buddy that went 5.90's on a 357W. Good piston and good rods with a 175 shot. It was in a coupe body mustang. With it set up right 351's will run good.

SlowJoe · 02-03-2011, 02:07 PM

this says a 357@6000 rpm needs about 619 cfm at .90 ve. i think alot of people put over size carbs on.

http://www.classictruckshop.com/garage/shopmathcfm1.php

BIGDATOWN · 02-03-2011, 02:21 PM

^^ qft

swammi · 02-03-2011, 03:08 PM

i got a .545 and .565 294 304 duration its a crane what do yall thinks about this cam. will it work in my combo

02-03-2011, 06:12 AM	#1
swammi magnaflow lover Join Date: Nov 2009 Location: pisgah al Posts: 150	thoughts on 351 vs 306 what do yall think of a 351w over a slightly built 306 the windsor is a 77 model block with it bored .030 over and a fresh bottom end . the 306 has scat cast crank,a set of some kind of rods looks like summit stage 1 rods and forged speed pro 9.53 to 1 forged flat tops. i will be running procomp 190 heads , comp cams pro magnum roller rockers,performer rpm airgap intake, and a q650 quick fuel carb.any suggestions on a flat tappet cam for a 351w . the setup will be 5 speed . thanks in advance for any help. __________________ 97 f150 lariat excab tow rig 93 mustang gt under construction

02-03-2011, 11:33 AM	#4
swammi magnaflow lover Join Date: Nov 2009 Location: pisgah al Posts: 150	the carb is a q 650 drag carb __________________ 97 f150 lariat excab tow rig 93 mustang gt under construction

02-03-2011, 11:40 AM	#5
SlowJoe Mind Blowing Join Date: Jun 2006 Location: Dawsonville Ga Posts: 3,913	351w! the carb should be good as long as you dont turn a lot of rpms. __________________ Slow Joe Racing 2008 dodge ram 5.7 HEMI 1993 lx with a 289 and a 3 speed on the floor WTB 1955 t-bird project

02-03-2011, 11:48 AM	#6
qkjuicedpony Dayuuuuuuum!!!!! Join Date: Dec 2004 Location: Dallas GA Posts: 2,933	Run the 351w and do swap to a roller cam. The carb will be fine but may require some fine tuning if you plan on going over 6k rpms. __________________ 86 Mustang Gt......Mods piling up in my garage. 07 F350 dooly.....Tows my fifth wheel

02-03-2011, 01:53 PM	#7
H8IMPORTS Member Join Date: Jan 2011 Posts: 82	351W! 351 all the way! If you could go to a roller cam it would be better but a good hyd flat tappet cam would be ok as well. I had a buddy that went 5.90's on a 357W. Good piston and good rods with a 175 shot. It was in a coupe body mustang. With it set up right 351's will run good. __________________ Just your average 92 Coupe with a Cam Only 302! Drive it like you stole it because everyone dies but not everyone lives!

02-03-2011, 07:23 AM	#2
BIGDATOWN Senior Member Join Date: Aug 2010 Posts: 221	My only thoughts is on the heads that they will be very large for a 306. My opinion is they would work much better on the 351 but you have to change valve springs on the heads for flat tappet/and depending on if it is hydraulic or solid.

02-03-2011, 08:25 AM	#3
coupe Super Moderator Join Date: Dec 2004 Posts: 6,313	351W. The 650 carb will run out of steam, unless it's been worked over. Change to a roller cam...it's rather inexpensive horsepower.

02-03-2011, 02:07 PM	#8
SlowJoe Mind Blowing Join Date: Jun 2006 Location: Dawsonville Ga Posts: 3,913	this says a 357@6000 rpm needs about 619 cfm at .90 ve. i think alot of people put over size carbs on. http://www.classictruckshop.com/garage/shopmathcfm1.php __________________ Slow Joe Racing 2008 dodge ram 5.7 HEMI 1993 lx with a 289 and a 3 speed on the floor WTB 1955 t-bird project Last edited by SlowJoe; 02-03-2011 at 02:17 PM.

02-03-2011, 02:21 PM	#9
BIGDATOWN Senior Member Join Date: Aug 2010 Posts: 221	^^ qft

02-03-2011, 03:08 PM	#10
swammi magnaflow lover Join Date: Nov 2009 Location: pisgah al Posts: 150	i got a .545 and .565 294 304 duration its a crane what do yall thinks about this cam. will it work in my combo __________________ 97 f150 lariat excab tow rig 93 mustang gt under construction