hello, I'm new

J/SA Grand Prix · 11-20-2007, 02:59 PM

Oh, ok so from my understanding the 250hp motors now were factored to 315hp now, where they were originally factored at 250hp and NHRA made them 315 now?

Harry 6674 · 11-20-2007, 04:07 PM

Yes, the factored 315 hp is what you use to determine your weight which determines your natural class then go from there. Get all the weight out you can then put what you need back in in better places.Have fun thats big time important or it gets to be work.

Mark Yacavone · 11-20-2007, 04:14 PM

The 72 Pontiacs were rated differently with a new net rating system. NHra just brought those engines up to where they were more in line with the 71's. The head and intake casting numbers were the only difference, spec -wise.

J/SA Grand Prix · 11-21-2007, 02:15 AM

So this particular motor doesn't call for the 7M5 heads or the #485912 intake? Sorry about all the questions, just trying to figure out what all I need to get!

Don Himes · 11-21-2007, 02:23 AM

Jake, you've got to get yourself aquainted with a rule book and nhra.com. The Lucas Oil page in particular. On the right side of the Lucas page you'll see the word "competition". That will draw down to a list of links. Look for "stock car classifications" and "engine blueprint specs". The blueprint specs call the motor, we're talking about, a 250 h.p. 455 cube engine. The classification sheet says at the top 250 h.p., 455 cube and at the bottom of the column it'll read 315. That is what NHRA has factored the 250 horse motor to. Do you have it now. It just seems more complicated than it really is or over the last 40 years I'm just used to it......

J/SA Grand Prix · 11-21-2007, 01:47 PM

Right on, the classification on NHRA didn't have the factored h.p on the bottom as the lucas oil page did, or I just over looked it. Thanks for all your help, Don. If you know of anyone with the 72' motor and which cam they used in it, please let me know. I believe we are going with a 30 inch tire and maybe 4.56 or 4.88 gears and when I call dynamic, through the faithful words of Don, they will give me the right combonation! I will also call Danny Ashley for a 71' HO carb. I hope we hit the right combonation and I wish you all good luck this up coming season. Lets keep these pontiacs going! I hope you all do as well as Tibor Kadar did this season!

Don Himes · 11-21-2007, 02:08 PM

Jake, the 4.56 gears worked fine on my old K/SA wagon at 4395 pounds. That makes your combo at 4108 pounds needing a 4.33 gear with the 4.56's being the most you'll need. Remember what everyone has told you, it's a "torque" motor, not a "RPM" motor. Your going to go thru the traps at about 6000, not 6500 or 6800, or 7000. I'm going to get in touch with my buddy Todd. He just finished his motor and it ran very well. Maybe he can come up with something I've forgotten......at my advanced age, I forget a lot of stuff..........Oh, by the way, I have an old phone # for Danny Ashley. If you need it, let me know...................later......

11-20-2007, 02:59 PM	#1
J/SA Grand Prix Junior Member Join Date: Nov 2007 Posts: 25 Likes: 0 Liked 0 Times in 0 Posts	Re: hello, I'm new Oh, ok so from my understanding the 250hp motors now were factored to 315hp now, where they were originally factored at 250hp and NHRA made them 315 now?

11-20-2007, 04:07 PM	#2
Harry 6674 Senior Member Join Date: Dec 2006 Posts: 589 Likes: 0 Liked 0 Times in 0 Posts	Re: hello, I'm new Yes, the factored 315 hp is what you use to determine your weight which determines your natural class then go from there. Get all the weight out you can then put what you need back in in better places.Have fun thats big time important or it gets to be work.

11-20-2007, 04:14 PM	#3
Mark Yacavone Veteran Member Join Date: Mar 2002 Location: Miles From Nowhere Posts: 7,817 Likes: 2,907 Liked 5,124 Times in 1,953 Posts	Re: hello, I'm new The 72 Pontiacs were rated differently with a new net rating system. NHra just brought those engines up to where they were more in line with the 71's. The head and intake casting numbers were the only difference, spec -wise. __________________ "We are lucky we don't get as much Government as we pay for." Will Rogers

11-21-2007, 02:23 AM	#5
Don Himes Member Join Date: Nov 2001 Location: Port Charlotte, Fla. Posts: 160 Likes: 0 Liked 0 Times in 0 Posts	Re: hello, I'm new Jake, you've got to get yourself aquainted with a rule book and nhra.com. The Lucas Oil page in particular. On the right side of the Lucas page you'll see the word "competition". That will draw down to a list of links. Look for "stock car classifications" and "engine blueprint specs". The blueprint specs call the motor, we're talking about, a 250 h.p. 455 cube engine. The classification sheet says at the top 250 h.p., 455 cube and at the bottom of the column it'll read 315. That is what NHRA has factored the 250 horse motor to. Do you have it now. It just seems more complicated than it really is or over the last 40 years I'm just used to it...... __________________ Don Himes 2075

11-21-2007, 01:47 PM	#6
J/SA Grand Prix Junior Member Join Date: Nov 2007 Posts: 25 Likes: 0 Liked 0 Times in 0 Posts	Re: hello, I'm new Right on, the classification on NHRA didn't have the factored h.p on the bottom as the lucas oil page did, or I just over looked it. Thanks for all your help, Don. If you know of anyone with the 72' motor and which cam they used in it, please let me know. I believe we are going with a 30 inch tire and maybe 4.56 or 4.88 gears and when I call dynamic, through the faithful words of Don, they will give me the right combonation! I will also call Danny Ashley for a 71' HO carb. I hope we hit the right combonation and I wish you all good luck this up coming season. Lets keep these pontiacs going! I hope you all do as well as Tibor Kadar did this season!

11-21-2007, 02:15 AM	#4
J/SA Grand Prix Junior Member Join Date: Nov 2007 Posts: 25 Likes: 0 Liked 0 Times in 0 Posts	Re: hello, I'm new So this particular motor doesn't call for the 7M5 heads or the #485912 intake? Sorry about all the questions, just trying to figure out what all I need to get!

11-21-2007, 02:08 PM	#7
Don Himes Member Join Date: Nov 2001 Location: Port Charlotte, Fla. Posts: 160 Likes: 0 Liked 0 Times in 0 Posts	Re: hello, I'm new Jake, the 4.56 gears worked fine on my old K/SA wagon at 4395 pounds. That makes your combo at 4108 pounds needing a 4.33 gear with the 4.56's being the most you'll need. Remember what everyone has told you, it's a "torque" motor, not a "RPM" motor. Your going to go thru the traps at about 6000, not 6500 or 6800, or 7000. I'm going to get in touch with my buddy Todd. He just finished his motor and it ran very well. Maybe he can come up with something I've forgotten......at my advanced age, I forget a lot of stuff..........Oh, by the way, I have an old phone # for Danny Ashley. If you need it, let me know...................later...... __________________ Don Himes 2075

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