Older Richmond 5-Speed in My 1969 Firebird - Page 10 - Lateral-g Forums

**Flash68** · #91 11-29-2009, 12:12 AM

Quote:

Originally Posted by Ron Fox

Would everyone please tell me what transmission you are running, your car's hp and torque rating, your 1st gear ratio, what rear gear you have, and what your 5th gear rpm is. I am just curious on everyone's response.

Thanks for the help.

Wow Ron I thought I had analysis paralysis.

TKO 600 w/ .64 OD
650-750hp/tq depending on boost
2.87 1st gear
3.70 rear gear
5th gear rpm around 2200rpm @ 75mph on recent road trip.

Ron Fox · #92 11-29-2009, 12:29 AM

Good one Flash.

This may sound like an odd question but would a high hp motor like yours with a low rpm 5th gear (2200) damage the motor in anyway?

Thanks.

**Flash68** · #93 11-29-2009, 12:34 AM

Quote:

Originally Posted by Ron Fox

Good one Flash.

This may sound like an odd question but would a high hp motor like yours with a low rpm 5th gear (2200) damage the motor in anyway?

Thanks.

No damage at that rpm that I am aware of. I have EFI which definitely helps, but if you are carbed and running at maybe 2000rpm or much lower you could get some bogging and bucking I guess? I don't know at what point/scenario some specific damage might occur though. I'll let someone more knowledgeable answer that one.

**GregWeld** · #94 11-29-2009, 10:42 AM

Ron Fox · #95 11-29-2009, 01:22 PM

I know I know but I can only learn by asking questions.

Thanks.

Ron Fox · #96 11-29-2009, 01:55 PM

Let me ask this question.

What first gear and what rear gear would I need to have a comfortable take off from 1st to 2nd gear in bumper to bumper traffic or pull up in and backing up in a parking spot without the car wanting to take off on me? (with 600+ hp)

Thanks.

**camcojb** · #97 11-29-2009, 02:05 PM

Quote:

Originally Posted by Ron Fox

Let me ask this question.

What first gear and what rear gear would I need to have a comfortable take off from 1st to 2nd gear in bumper to bumper traffic or pull up in and backing up in a parking spot without the car wanting to take off on me? (with 600+ hp)

Thanks.

it doesn't work that way. Just because it has 600 hp does not mean it wants to "take off on you......." You still control the gas pedal.

**GregWeld** · #98 11-29-2009, 04:23 PM

Ron --

You need to understand HORSEPOWER.... You don't have "600 Horsepower" at idle or just off idle -- or even at 1500 rpms....

The questions you're asking are just all wrong. Nobody can answer them. There are so many variables - like tire size - cam - cubic inches - rear gear...

Is the motor RADICAL - or is it a pretty tame build - that just happens to make that HP - a Twin Turbo small block can make 1000 hp and drive like a Lexus around town... a big block Pontiac will make so much low end torque (the only good part of any Pontiac motor) that you won't need HORSEPOWER - which by the way - is ONLY a mathematical equation of how much TORQUE you make and what RPMS you're turning...

So if you're big block motor is built with a .700 lift cam - with radical duration - and doesn't make ANY torque below 2500 RPMs -- you're going to have a motor that SUCKS big time for the kind of driving you're asking about... but if you build a nice big block Pontiac with 455 cubic inches and are making 400 ft lbs of TQ at 2000 rpms --- it's going to drive easy - and like a street car should. It's going to FEEL powerful - without being a beast to drive.

So if you build a drivetrain like everyone is telling you to --- a 500 hp 455 Pontiac - Tremec 5 or 6 speed OVERDRIVE - 3:70ish rear gears.... 18" 40 series or 19" 35 series tires -- you're going to have a very nice combo that you'd love to drive and will be hugely powerful without issues. You want to snot it up a couple of notches and start making 700 hp - then it's still all about the CAM and where it makes it's power... and THEN you figure what gears/tranny you NEED to make that combo work.

Ron Fox · #99 11-29-2009, 09:58 PM

Thanks Greg and JB and everyone else for your in site, opinions, and help.

I will have more questions about my car and parts as each stage of my build comes along. Now if I could only get my builder to start the metal stage...

Thanks.

Vegas69 · #**100** 11-29-2009, 11:49 PM

Quote:

Originally Posted by Ron Fox

Good one Flash.

This may sound like an odd question but would a high hp motor like yours with a low rpm 5th gear (2200) damage the motor in anyway?

Thanks.

I can cruise at 1600-2000 rpm in 5th with mine and it's got a pretty big cam on a 114 lobe separtation. Of course I only do it on flat ground under minimum loads. Big block torque.