Rear Gear Question - Page 2

SStockDart · 09-16-2013, 10:18 PM

My advise it: "Listen to Mark" and save some money down the road....For that matter, if anyone can make a 2 ton car run.......442Olds..knows

njk53 · 09-17-2013, 11:04 AM

Transmission is a TH 350 with a 4800 stall converter. Engine RPM through the lights is 6200

gsa612 · 09-17-2013, 11:28 AM

Is it 2.75 low, how fast have you gone 60', ET, mph?, shift points?. I would try 4.88, your 600 lbs. heavier than me.The difference between .56's and .88's is about 300 rpm on top end.You have to move that weight off the line in order for it to ET well.

njk53 · 09-17-2013, 01:29 PM

First gear is 2.75. Fastest the car has ever gone was at Martin last August. 60' was 1.62 ET was 12.25 @ 108 MPH. We have played around with shift points from 6150 to 6250. Didn't really make a difference. We were at the track last Friday and the best I went was 12.39 @ 107. The air was good and it was a nice cool day, should have gone better than what we did.

I have to admit, most of the time when I go through the lights, the shift light does not come on in 3rd gear, so I am not reaching the set engine RPM.

My brother and I feel the car has more in it but are struggling to find the extra ET and speed.

gsa612 · 09-17-2013, 02:47 PM

Something's not right, your trap rpm seems low with 4.56's, I don't know what cam you got. What's the spring pressure? I'm going through at 6700 with.56's with the 94'tire. Mine goes 11 teens on a average day with 1.45 60' in G.(with no ice or lw oil).I found on these motors because of the cyl. heads (105cc) and the lower piston dome require a different set up than a 325-396 in terms of total timing, jetting, cam position, usable rpm. I would try .88's on your car if the springs check out ok. On a side note NHRA's Danny Gracia ran a wagon like yours a while back(80's). I was going through teardown 20+ years ago and he gave me some good advice/tips on the 402 combo lol..

njk53 · 09-17-2013, 04:07 PM

GSA612 you have a PM

ss3011 · 09-17-2013, 04:42 PM

Would you happen to have run the engine on a dyno, and know what the basic HP and Torque curves are ? When you say you have a 4800 stall converter, is that what it flashes to off the starting line ?

njk53 · 09-18-2013, 08:16 AM

I have dyno sheets. Yes the conver flashes @ 4800 at the starting line.

ss3011 · 09-18-2013, 08:54 AM

Just curious what rpm peak torque and peak HP is at. Converter seems pretty tight.

njk53 · 09-24-2013, 03:01 PM

Quote:

Originally Posted by ss3011

Just curious what rpm peak torque and peak HP is at. Converter seems pretty tight.

I'll look at the dyno sheet and let you know.

09-16-2013, 10:18 PM	#11
SStockDart VIP Member Join Date: Dec 2007 Location: Arizona, Texan forever Posts: 1,134 Likes: 770 Liked 515 Times in 188 Posts	Re: Rear Gear Question My advise it: "Listen to Mark" and save some money down the road....For that matter, if anyone can make a 2 ton car run.......442Olds..knows __________________ Gary Hansen - SS/FA 4911, B/SA 4911

09-17-2013, 11:04 AM	#12
njk53 Senior Member Join Date: Jul 2007 Location: East China, MI Posts: 504 Likes: 0 Liked 0 Times in 0 Posts	Re: Rear Gear Question Transmission is a TH 350 with a 4800 stall converter. Engine RPM through the lights is 6200 __________________ Nelson Kowal Stock 345

09-17-2013, 11:28 AM	#13
gsa612 Senior Member Join Date: Jan 2008 Location: 100th Meridian Posts: 570 Likes: 116 Liked 280 Times in 139 Posts	Re: Rear Gear Question Is it 2.75 low, how fast have you gone 60', ET, mph?, shift points?. I would try 4.88, your 600 lbs. heavier than me.The difference between .56's and .88's is about 300 rpm on top end.You have to move that weight off the line in order for it to ET well.

09-17-2013, 01:29 PM	#14
njk53 Senior Member Join Date: Jul 2007 Location: East China, MI Posts: 504 Likes: 0 Liked 0 Times in 0 Posts	Re: Rear Gear Question First gear is 2.75. Fastest the car has ever gone was at Martin last August. 60' was 1.62 ET was 12.25 @ 108 MPH. We have played around with shift points from 6150 to 6250. Didn't really make a difference. We were at the track last Friday and the best I went was 12.39 @ 107. The air was good and it was a nice cool day, should have gone better than what we did. I have to admit, most of the time when I go through the lights, the shift light does not come on in 3rd gear, so I am not reaching the set engine RPM. My brother and I feel the car has more in it but are struggling to find the extra ET and speed. __________________ Nelson Kowal Stock 345

09-17-2013, 02:47 PM	#15
gsa612 Senior Member Join Date: Jan 2008 Location: 100th Meridian Posts: 570 Likes: 116 Liked 280 Times in 139 Posts	Re: Rear Gear Question Something's not right, your trap rpm seems low with 4.56's, I don't know what cam you got. What's the spring pressure? I'm going through at 6700 with.56's with the 94'tire. Mine goes 11 teens on a average day with 1.45 60' in G.(with no ice or lw oil).I found on these motors because of the cyl. heads (105cc) and the lower piston dome require a different set up than a 325-396 in terms of total timing, jetting, cam position, usable rpm. I would try .88's on your car if the springs check out ok. On a side note NHRA's Danny Gracia ran a wagon like yours a while back(80's). I was going through teardown 20+ years ago and he gave me some good advice/tips on the 402 combo lol..

09-17-2013, 04:07 PM	#16
njk53 Senior Member Join Date: Jul 2007 Location: East China, MI Posts: 504 Likes: 0 Liked 0 Times in 0 Posts	Re: Rear Gear Question GSA612 you have a PM __________________ Nelson Kowal Stock 345

09-17-2013, 04:42 PM	#17
ss3011 Senior Member Join Date: Feb 2002 Location: Southeast Michigan Posts: 892 Likes: 65 Liked 229 Times in 107 Posts	Re: Rear Gear Question Would you happen to have run the engine on a dyno, and know what the basic HP and Torque curves are ? When you say you have a 4800 stall converter, is that what it flashes to off the starting line ?

09-18-2013, 08:16 AM	#18
njk53 Senior Member Join Date: Jul 2007 Location: East China, MI Posts: 504 Likes: 0 Liked 0 Times in 0 Posts	Re: Rear Gear Question I have dyno sheets. Yes the conver flashes @ 4800 at the starting line. __________________ Nelson Kowal Stock 345

09-18-2013, 08:54 AM	#19
ss3011 Senior Member Join Date: Feb 2002 Location: Southeast Michigan Posts: 892 Likes: 65 Liked 229 Times in 107 Posts	Re: Rear Gear Question Just curious what rpm peak torque and peak HP is at. Converter seems pretty tight.