Running RWD

G

Gigarange

New member
I've got a '93 S10 4x4 with a '99 4.3L Vortec motor in it along with a '91 Scycone transfer case.

I read in the faq
49. Can I drive my truck in RWD without damaging anything?

Making the truck RWD requires removing the forward propshaft. Before removal, make marks on the location of how the propshaft was bolted to the transfer case. The propshaft is balanced, if you dont put it back in exactly the position you took it out, vibration issues can arrise

I'm looking for a little more clarification.
I'm wanting to dyno my truck but the only AWD chassis dyno thats even remotly close is a $100 ferry ride plus 4.5hrs each way driving and I'd have to cross over into the US to get there, which I'm wanting to avoid.
Buddy of mine owns a shop and has a 2wd dyno that I'd like to run on. Basically want to know if I can run with the front propshaft removed without causeing damage to anything. And if I do remove it, do I need to put anything into the transfer case to keep anything from leaking out on the drive out there and during the subsequent dyno runs?
I'm hopeing I can slide under my truck, mark it, unbolt it and run it without any issue's. The biggest reason I'm asking would be that I use this truck 6 days a week to work.

I've taken a '98 Subaru 2.5RS, '90 Nissan Skyline GTS-T off the line with this truck, and can keep up to a '98 Lexus SC400 that just ran a 191WHP on said dyno minutes before. So I'm now very curuios as to what my truck is putting down for HP.

Thanks for any info
 
gkrcr882

gkrcr882

SyTyless......for now!
Re: Running RWD

You should have no problem doing dyno runs in RWD, that is how most people do it anyway since AWD dynos are somewhat rare. Just don't drive it for months on end and you should be fine. Just watch out, as the rear end will want to break loose during hard acceleration. Sure it's a little scary, but it's also alot of fun. Let us know what kind of numbers you pull. BTW, welcome to the board!:tup:
 
G

Gigarange

New member
Re: Running RWD

awesome thanks for the reply.
Gonna try tracking down some tuning options before I actually go to the dyno, so won't be any #'s for a little while. Guy who runs the dyno does great work with little to work with.

That Lexus...with only using a SAFC on a stock SC400 he managed to get 40WHP out of it. no mods to the car other then the SAFC...and Nitrous...it was 190.1 N/A and 297.3 on the juice.
 
SeattleSy#1255

SeattleSy#1255

Category 5 Conservative
Re: Running RWD

don't you have a decrees in 35% whp?

bascially, how do you dyo a AWD vehicle on a RWD dyno and get accurate numbers?
 
George Blake

George Blake

DONATING MEMBER
Re: Running RWD

This came up before a long time ago. From what I remember, being there was no "pulling" affect on the front, the viscous would heat up and apply more force to the rear. It won't be a 35% loss but it won't be a 100% accurate either. You won't get a 100% reading unless your viscous is damaged and not allowing any transfer of torque. That means overheated and locked solid. It seems there was a factor they used for loss correction but that was a long time ago.
 
SeattleSy#1255

SeattleSy#1255

Category 5 Conservative
Re: Running RWD

George Blake said:
This came up before a long time ago. From what I remember, being there was no "pulling" affect on the front, the viscous would heat up and apply more force to the rear. It won't be a 35% loss but it won't be a 100% accurate either. You won't get a 100% reading unless your viscous is damaged and not allowing any transfer of torque. That means overheated and locked solid. It seems there was a factor they used for loss correction but that was a long time ago.
Click to expand...

all the more reason to find a AWD dyno if you can
 
gkrcr882

gkrcr882

SyTyless......for now!
Re: Running RWD

Good link! The T-case operation is actually quite simple when you think about it.:)
 
G

Gigarange

New member
Re: Running RWD

Great info in that post.
Although still more questions and worries on my part though. There dosen't seem to be any agreement on wheather a dyno run with the front prop shaft removed will do damage or not.

I just won a free base line run on the dyno I was talking about earlier on a poker run that I went on yesterday...so now I'm really curious.
Biggest question I have now was asked in the linked post as well. If I blow up the viscous coupler by running on the dyno will it cause front axle to no longer be driven or will it cause lockup of AWD system and not take away power during turning etc?
 
SEL777

SEL777

One of 101
Re: Running RWD

What about running FWD only? This would only be for a day or two approx. 120 miles. I need to replace the U-joint in the rear on my DD. Sorry for the hihack but, I have not seen this mentioned. I've done this before in my FS 89 Blazer for the same reason but it had locking hubs for the front.
 
Loeryder

Loeryder

New member
Re: Running RWD

With the front propshaft out the flange of the T-Case is till secured with a nut, keeping everything sealed up tight.

The rear driveshaft slips into a pinion seal and therefore the yoke holds the fluid in.
Without a rear driveshaft the fluid will be gushing out all over.

I dyno'd my Ty on a 2wd dyno one time and I never will again.
I can't say for sure if it damaged my T case but there was a huge difference in readings from the 2wd dynojet and an AWD Mustang dyno.
Instead of bragging about the absurdly higher reading from the Dynojet I go with the more realistic AWD dyno #s.
 
G

Gigarange

New member
Re: Running RWD

there is also large discrepency's between different brands of Dyno's wheather they're 4-wheel or 2-wheel dyno's.
I can't remember the exact numbers but I'll be running on a Dyno Dynamics.

Dynoing on an AWD dyno is pretty much out of the question I'm just trying to decide if the risk is worth the dyno run in RWD or not.
 
You must log in or register to reply here.
Top