350 - 270 Combo Horsepower - Page 3

Daran Summerton · 06-19-2015, 10:09 AM

K/SA is a great class! Had a 1.45 last time out so we are inching closer to the 6.99 goal

njk53 · 06-19-2015, 02:11 PM

Quote:

Originally Posted by Daran Summerton

K/SA is a great class! Had a 1.45 last time out so we are inching closer to the 6.99 goal

Please don't rub salt into the wound. LOL

ron mattson · 06-19-2015, 02:22 PM

400 hp is no problem 425/435 for a killer!!

Chris Hill · 06-19-2015, 04:27 PM

400 hp is only 1.15 hp/in3 for a 350, so it should easily make 400 hp.

A good one should make north of 450 hp.

Jim Hanig · 06-21-2015, 10:05 PM

Jim Hughes runs that engine with a stick, and runs pretty good, I think the 402 is a bit harder than the 350 . If you get the right engine builder it should be a fair engine and yes I have worked on a couple. They make about 480 or so.

HP HUNTER · 06-21-2015, 10:14 PM

Quote:

Originally Posted by Jim Hanig

Jim Hughes runs that engine with a stick, and runs pretty good, I think the 402 is a bit harder than the 350 . If you get the right engine builder it should be a fair engine and yes I have worked on a couple. They make about 480 or so.

"They make about 480 or so"

Thats pretty accurate, with a peak of 6400 RPM.
488 HP
497 TQ

Dwight Southerland · 06-22-2015, 12:38 AM

Jim Hughes runs a 70 Nova with a 350 hp 402. Different animal than the '71

njk53 · 06-22-2015, 09:53 AM

Quote:

Originally Posted by Dwight Southerland

Jim Hughes runs a 70 Nova with a 350 hp 402. Different animal than the '71

Yes the 1970 402 is a way better motor. It also has an intake manifold that has a higher rise which produces better air/fuel flow than the 71 manifold. The 71 intake is flat as a pancake. The 70 engine is also 10.25-1 compression ratio. The 71 engine has a 9:28-1 CR.

gsa612 · 06-22-2015, 11:28 PM

According to the tech. specs the 70/350 and 71/300 402 both run the same intake (flat #287).In order to get the 300/402 to be competitive you need a custom grind camshaft,if you have one of the "off the shelf" cams your leaving 2 tenths on the table,There basically a 325/396 cam with more ex. lift,but don't compliment the semi-open head (105cc) on the 300/402 which produces low torque #'s.With the right combo,cam/converter/gear,carb,light trans,good ring seal,right tune-up ( jetting,timing etc.) it should run with the majority of the cars in K. JMO gsa612

Dwight Southerland · 06-23-2015, 08:01 AM

Here's a picture of a 287 manifold. Doesn't look flat to me. The differences between the '70 and '71 engines are the heads (290 heads flow well and have a good combustion chamber design, 820 heads flow okay but the combustion chamber is sucky; not sure about the other '71 heads), camshaft, and 1.7 points of blueprinted compression (11.3 for the '70 and 9.6 for the '71). See www.classracerinfo.com for the actual calculated compression ratios.

06-19-2015, 10:09 AM	#21
Daran Summerton Senior Member Join Date: Jun 2003 Location: Las Vegas nv Posts: 600 Likes: 18 Liked 66 Times in 37 Posts	Re: 350 - 270 Combo Horsepower K/SA is a great class! Had a 1.45 last time out so we are inching closer to the 6.99 goal __________________ 72 cutlass

06-19-2015, 02:22 PM	#23
ron mattson Member Join Date: Nov 2005 Location: cloquet mn Posts: 464 Likes: 17 Liked 66 Times in 29 Posts	Re: 350 - 270 Combo Horsepower 400 hp is no problem 425/435 for a killer!! __________________ Ron Mattson 5015 STK

06-19-2015, 04:27 PM	#24
Chris Hill Senior Member Join Date: Jan 2002 Posts: 655 Likes: 8 Liked 244 Times in 26 Posts	Re: 350 - 270 Combo Horsepower 400 hp is only 1.15 hp/in3 for a 350, so it should easily make 400 hp. A good one should make north of 450 hp. __________________ Chris Hill https://ihmusedparts.com

06-21-2015, 10:05 PM	#25
Jim Hanig Senior Member Join Date: Aug 2006 Location: Pukwana SD Posts: 860 Likes: 554 Liked 99 Times in 49 Posts	Re: 350 - 270 Combo Horsepower Jim Hughes runs that engine with a stick, and runs pretty good, I think the 402 is a bit harder than the 350 . If you get the right engine builder it should be a fair engine and yes I have worked on a couple. They make about 480 or so.

06-22-2015, 12:38 AM	#27
Dwight Southerland VIP Member Join Date: Dec 2001 Location: Arkansas - In the middle of everything. Posts: 1,999 Likes: 63 Liked 772 Times in 192 Posts	Re: 350 - 270 Combo Horsepower Jim Hughes runs a 70 Nova with a 350 hp 402. Different animal than the '71 __________________

06-22-2015, 11:28 PM	#29
gsa612 Senior Member Join Date: Jan 2008 Location: 100th Meridian Posts: 569 Likes: 116 Liked 280 Times in 139 Posts	Re: 350 - 270 Combo Horsepower According to the tech. specs the 70/350 and 71/300 402 both run the same intake (flat #287).In order to get the 300/402 to be competitive you need a custom grind camshaft,if you have one of the "off the shelf" cams your leaving 2 tenths on the table,There basically a 325/396 cam with more ex. lift,but don't compliment the semi-open head (105cc) on the 300/402 which produces low torque #'s.With the right combo,cam/converter/gear,carb,light trans,good ring seal,right tune-up ( jetting,timing etc.) it should run with the majority of the cars in K. JMO gsa612 Last edited by gsa612; 06-23-2015 at 12:20 AM.

06-23-2015, 08:01 AM	#30
Dwight Southerland VIP Member Join Date: Dec 2001 Location: Arkansas - In the middle of everything. Posts: 1,999 Likes: 63 Liked 772 Times in 192 Posts	Re: 350 - 270 Combo Horsepower Here's a picture of a 287 manifold. Doesn't look flat to me. The differences between the '70 and '71 engines are the heads (290 heads flow well and have a good combustion chamber design, 820 heads flow okay but the combustion chamber is sucky; not sure about the other '71 heads), camshaft, and 1.7 points of blueprinted compression (11.3 for the '70 and 9.6 for the '71). See www.classracerinfo.com for the actual calculated compression ratios. __________________