615 SR20 or 632 12 Degree

January 04, 2018, 11:59 AM

TOP38

quote:
Originally posted by Shawn Pinkerton:
quote:
Originally posted by TOP38:

Shawn and Ed

We all know stop MPH is as much about HP and the T Stop set up! Both contribute to finish line MPH.

Unless your really under or over rev'ing the motor out of its power band I don't see much impact,,, typical gearing in these combo's is 4.10's and 4.30's.... Between these two, ET all out is a bit better with he 4.30's but not MPH

How much does rear gear play a factor in this?

January 04, 2018, 12:06 PM

Lincoln

quote:
Originally posted by Shawn Pinkerton:
[QUOTE]Originally posted by TOP38:

Shawn and Ed

We all know stop MPH is as much about HP and the T Stop set up! Both contribute to finish line MPH.

How much does rear gear play a factor in this?

Thinking the tire and it's ability to grow may mean more.

January 04, 2018, 03:14 PM

TOP38

quote:
Originally posted by Lincoln:
quote:
Originally posted by Shawn Pinkerton:
[QUOTE]Originally posted by TOP38:

Shawn and Ed

We all know stop MPH is as much about HP and the T Stop set up! Both contribute to finish line MPH.

How much does rear gear play a factor in this?

Thinking the tire and it's ability to grow may mean more.

Now u added another variable!!! Apples to apples.

January 05, 2018, 10:18 AM

MightyBirdF145

I have run everything from 4:10 to 4:56 with the Big Bubba or the Hoosier 33.5, 34.5 and a new 35" tire.

Tire, gear ratio and converter all effect speed, especially on the stop.

Hi Al, Happy New Year.

Shawn

January 05, 2018, 01:28 PM

TOP38

quote:
Originally posted by MightyBirdF145:
I have run everything from 4:10 to 4:56 with the Big Bubba or the Hoosier 33.5, 34.5 and a new 35" tire.

Tire, gear ratio and converter all effect speed, especially on the stop.

Hi Al, Happy New Year.

Shawn

And to you and Jackie also! See you in the spring if it ever thaws out this winter!

April 10, 2018, 06:01 AM

Tony Barrett

Update: Thank you all for your input it was very helpful. I wound up ordering a 632 11 degree aluminum block. I am having James from JA Performance do the build.

April 10, 2018, 06:10 AM

1320racer

Good decision

April 10, 2018, 06:49 AM

SCDIV1

And now you will or may need or want...

A new converter
A new bigger carb

40 spline axles and spool if you don't already have them

Big tires and beadlocks

A wing...

A Hans device.....

To go 8.90 at 185 + or - a couple MPH's....

Just sayin.....

April 10, 2018, 07:00 AM

jimmyc

I’d bet it goes quicker than that. My uncles 604 sr20 went 8:90@183

April 11, 2018, 03:56 PM

Will Harrison

quote:
Originally posted by jimmyc:
I’d bet it goes quicker than that. My uncles 604 sr20 went 8:90@183

agree, it'll run better then that. I've been 191 @8.90 with 100 less cubic inches and an iron block..

But yeah, he'll want 40 spline axles for sure and the other stuff mentioned, but thats to be expected I would imagine

April 12, 2018, 01:43 PM

Tony Barrett

SCDIV1
Already have everything other than carb and convertor. But you have a good point in that you shouldn't do things like this unless you understand all the costs. I have been racing for over 30 years so I fully understand the costs involved.

April 12, 2018, 01:59 PM

imakehp

quote:
Originally posted by SCDIV1:
And now you will or may need or want...

A new converter
A new bigger carb

40 spline axles and spool if you don't already have them

Big tires and beadlocks

A wing...

A Hans device.....

To go 8.90 at 185 + or - a couple MPH's....

Just sayin.....

One reason I love drag racing....

Do whatever you want, how you want, when you want and it's nobody else's business..
Man I love 'merica..lol

April 12, 2018, 04:29 PM

SCDIV1

My posts never implied Tony should not do whatever he wants. Just an observation that moving up in engine power usually leads to other changes to make it all work well and be safe. I myself think about stepping my MPH’s up but am comfortable with what I run now. To each his own and JA is a great guy and engine builder. Good Luck with it.....

April 13, 2018, 12:51 PM

BP758

quote:
Originally posted by Tony Barrett:
I am considering Building a new engine. I am looking for a high MPH SC combination. I was leaning towards a 632 with 12 degree heads but it was suggested to me to look at a 615 with SR20 heads. I am nor looking to save money but I don't want to waste money either. I am looking for recommendations for either combinations.

If it were me...
632 all alum, SR20 heads, the biggest best roller lifters you can afford, big push rods etc... too many great combos in 632 not to take advantage.

Sorry Tony I missed your update good call!!!!!!

April 13, 2018, 01:44 PM

TOP38

quote:
Originally posted by stk 758 BP!:
quote:
Originally posted by Tony Barrett:
I am considering Building a new engine. I am looking for a high MPH SC combination. I was leaning towards a 632 with 12 degree heads but it was suggested to me to look at a 615 with SR20 heads. I am nor looking to save money but I don't want to waste money either. I am looking for recommendations for either combinations.

If it were me...
632 all alum, SR20 heads, the biggest best roller lifters you can afford, big push rods etc... too many great combos in 632 not to take advantage.

Sorry Tony I missed your update good call!!!!!!

Never give away cubic inches!!!

I have a Pro20 (Dart Version) 632, 6.78 at 197 off the trailer at the start of last year (New combo). car is 1840lbs,, that's a 190 SC combo.

I'd recommend the Dart heads over the Brodix head for this CID also.

April 13, 2018, 02:25 PM

BP758

quote:
Originally posted by TOP38:
quote:
Originally posted by stk 758 BP!:
quote:
Originally posted by Tony Barrett:
I am considering Building a new engine. I am looking for a high MPH SC combination. I was leaning towards a 632 with 12 degree heads but it was suggested to me to look at a 615 with SR20 heads. I am nor looking to save money but I don't want to waste money either. I am looking for recommendations for either combinations.

If it were me...
632 all alum, SR20 heads, the biggest best roller lifters you can afford, big push rods etc... too many great combos in 632 not to take advantage.

Sorry Tony I missed your update good call!!!!!!

Never give away cubic inches!!!

I have a Pro20 (Dart Version) 632, 6.78 at 197 off the trailer at the start of last year (New combo). car is 1840lbs,, that's a 190 SC combo.

I'd recommend the Dart heads over the Brodix head for this CID also.

^^^^^^!

April 16, 2018, 09:06 AM

topd1332

Can definatly run a 9 inch converter in a 12 degree spreadport motor. I have ran in 6s on motor with a 9 inch and sprayed to 6.6s with the same converter