r154 top gear speeds?

Supralover87

Beauty and the Boost
May 21, 2007
84
0
0
Ohio
I just got done doing my 154 swap and was surprised to see that at the same speeds in my auto i was doing 500 rpm more with the manual... are the speed to rpm ratios really that different from auto to manual?

EX: auto at 60 was 2100rpm
Manual (r154) 60 was 2500 to 2600

This worries me because it means my 5th gear will wind out very early :(

anyone else notice this?
 

Insidious Surmiser

Formerly 89jdm7m
May 12, 2006
2,172
0
0
Oceanfront
could have to do w/ the rear end (nevermind, i see you're talking about the same car)

just for reference... i had a 3.73 rear end and my gears went like so... (r-154) i also got 30+mpg (80mph @ 3,000rpm)

45
60
90
120
165

all speeds are at or very close to 6,500 rpm
 
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Supralover87

Beauty and the Boost
May 21, 2007
84
0
0
Ohio
What ratio LSD did 89 turbo's have? i thought it was 3.73? and i'm lucky if i get 15 mpg in my 88 turbo and i'm not a lead foot :( WTH???? lol

And 6 speed????
 
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lewis15498

Don't blame ebay cheapass
Sep 28, 2008
1,397
1
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Raynham, Massachusetts, United States
89jdm7m;1503765 said:
could have to do w/ the rear end (nevermind, i see you're talking about the same car)

just for reference... I had a 3.73 rear end and my gears went like so... (r-154) i also got 30+mpg (80mph @ 3,000rpm)

45
60
90
120
140
165


all speeds are at or very close to 6,500 rpm

wtf?

Supralover, was your car originally an auto? or W58?
EDIT: I see this was answered in the original post. IIRC the autos had either a 4.1 or a 4.3. This could explain it.
 

2jz88mk3

New Member
Dec 31, 2008
41
0
0
GVRA
raise your rev limit.

5th gear, 8000 rpm, 3.91 rear - with tires close to stock size will net you about 200 mph.

just rev the shit out of it... the r154 has room for teh speed.
 

lewis15498

Don't blame ebay cheapass
Sep 28, 2008
1,397
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Raynham, Massachusetts, United States
IJ.;1503804 said:
yeah ok......:nono:

crack%20kit%20en.JPG
 

lewis15498

Don't blame ebay cheapass
Sep 28, 2008
1,397
1
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Raynham, Massachusetts, United States
Supra lover, the R154 ratios are as follows
First Gear: 3.250:1
Second Gear: 1.955:1
Third Gear: 1.310:1
Fourth Gear: 1.00:1
Fifth Gear: 0.753:1

Jack the rear end of your car up and support it with jackstands. Throw the car in neutral. take some whiteout and make a mark on your tire (put it on tread so it will wear off. Put a mark on your driveshaft as well. Spin your driveshaft by hand until the tire makes one full rotation. However many times you spin the driveshaft to accomplish this is your differential ratio. Last measure the circumfrence of your rear tire. Using this data and simple math you can figure out exactly how fast you will be going at any RPM in any gear. You could even make a graph if your feeling extra geeky. Then if your not satisfied with the speed-RPM figures you can select a diff that better suits your needs.
 

hvyman

Dang Dude! No Way Man.
Staff member
Apr 17, 2007
12,568
1
0
Fullerton,CA
lewis15498;1503779 said:
wtf?

Supralover, was your car originally an auto? or W58?
EDIT: I see this was answered in the original post. IIRC the autos had either a 4.1 or a 4.3. This could explain it.

auto's have the same diff as manuals. the difference is what year the car is and n/a or turbo.

pre 89 turbos have a 3.91.
89+ tubros have a 3.73
all n/a have 4.3 open. sport package n/a has 4.3 lsd
iirc the 1jz cars have a 4.1 torsen.
 

lewis15498

Don't blame ebay cheapass
Sep 28, 2008
1,397
1
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Raynham, Massachusetts, United States
IJ.;1503847 said:
Auto's have a .705:1 top gear.

.753 with the R154 vs .705 with the auto would explain your difference.

hvyman;1503849 said:
auto's have the same diff as manuals. the difference is what year the car is and n/a or turbo.

pre 89 turbos have a 3.91.
89+ tubros have a 3.73
all n/a have 4.3 open. sport package n/a has 4.3 lsd
iirc the 1jz cars have a 4.1 torsen.

In which case I did not recall correctly lol.
 

2jz88mk3

New Member
Dec 31, 2008
41
0
0
GVRA
Supralover87;1503764 said:
I just got done doing my 154 swap

IJ.;1503804 said:
yeah ok......:nono:

lewis15498;1503818 said:

92TealSupra;1503838 said:

Damn you haters!!! make me dig it up ... sure here you go.

http://www.car-videos.net/tools/spe...7=&Redline=8000&Increment=1000&B1=Recalculate

keep in mind all mph numbers listed in the grid are with a 0.965% reduction

it lists 193.9 mph for 5th gear... 193.9 / 0.965 = 200.9 mph

----

so i said with close to stock tire size, 8000 rpm, 3.91 rear would net you ~200 mph...

anyone care to point out what im missing?

bring the hate!
 

2jz88mk3

New Member
Dec 31, 2008
41
0
0
GVRA
IJ.;1503975 said:
How does she raise the limit on a 7M for starters....

Not hating just don't post inane shit.

All right i was having a bit of fun with my claims of hate =P

It's no secret how one would go about to raise the rev limit. Obviously purchases are required.

I find that someone who is concerned that their r154 doesn't have enough speed in the gears, has enough power/budget to get there. It seems to take most cars around 500 bhp to reach 200 mph. If someone is concerned that 157 mph (the number for 5th gear and 6500 rpm for the specifics i've previously listed) is not fast enough, i would naturaly assume that have the power/budget to overcome the stock rev limit (purchase a standalone).

I'm still compelled to claim my comments: not inane...

Is that better? :icon_bigg
 

IJ.

Grumpy Old Man
Mar 30, 2005
38,728
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I come from a land down under
You're making far too many assumptions before posting and it's making your posts irrelevant and inane.

Find me a single post where the OP has stated she has anything like 500hp crank or wheel.
 

2jz88mk3

New Member
Dec 31, 2008
41
0
0
GVRA
IJ.;1503986 said:
You're making far too many assumptions before posting and it's making your posts irrelevant and inane.

Find me a single post where the OP has stated she has anything like 500hp crank or wheel.

Firstly, I made no assumtions of the OP's setup. I know nothing about it. My comments are directed only to someone (regardless of setup) who is concerned with the speed a r154 can deliver to them. If you want to go fast you need power.

I suppose I could have assumed instead, that the OP simply is not aware of the r154's ratios, because of their concern that it will "wind out to quickly"

Do you find it unreasonable to assume that someone who is concerned that 150+ mph is not enough, has some upgrades? Or should i have just said "unless you have upgrades you need not be concerned with being limited by the r154, and once you have certain upgrades (raised rev limit) the speed the r154 is capable of delivering to you will be increased like wise"?

I find it is worse for someone (anyone, not directed at the OP) with stock power to claim an r154 cannot deliver them the speed they desire, then for me to assume they have the power to breach the speed an r154 can deliver at stock rev limit.

No I have not seen any post to indicate anything about the OP's setup or circumstances. That info is not required for the comments i've made.
 

dragracer

GearHead
Oct 31, 2005
221
0
0
Churubusco
4th gear in the A340 auto is .705 ratio and 5th in the R154 is .753

Since your running 3.73 gears, all other stock ratios are lower.

JawsGear makes some 3.55 (3.50) dont remember.

It could be worse, like my 4.30 gears and 3200 rpm at 65

Nothing wrong with your setup. Thats what the factory designed. You were just used to the taller final gear ratio in the auto.

Just my 2 cents:icon_razz
 

Nghty89

Zombie Chicks Are Hot
Mar 26, 2008
978
0
0
7 Cities, VA
2jz88mk3;1504008 said:
Firstly, I made no assumtions of the OP's setup. I know nothing about it. My comments are directed only to someone (regardless of setup) who is concerned with the speed a r154 can deliver to them. If you want to go fast you need power.

I suppose I could have assumed instead, that the OP simply is not aware of the r154's ratios, because of their concern that it will "wind out to quickly"

Do you find it unreasonable to assume that someone who is concerned that 150+ mph is not enough, has some upgrades? Or should i have just said "unless you have upgrades you need not be concerned with being limited by the r154, and once you have certain upgrades (raised rev limit) the speed the r154 is capable of delivering to you will be increased like wise"?

I find it is worse for someone (anyone, not directed at the OP) with stock power to claim an r154 cannot deliver them the speed they desire, then for me to assume they have the power to breach the speed an r154 can deliver at stock rev limit.

No I have not seen any post to indicate anything about the OP's setup or circumstances. That info is not required for the comments i've made.


I believe IJ's problem is with you saying 8,000 rpm's on the rev limit. It's much more complicated than *just* getting a standalone and raising the limit.