Rb25 Weight issues

[Drftwell]

Ok i know this has already been talked about but i cant find anything but i would reallyl ike some feedback from someone who has actually swapped the motor in and went out and gave it hell on the curvies...... so heres my question:

Im planning on doing a rb25 swap..... but ive heard so much about how the weight kills the car...... ive got a 95 s14 im planning on putting the motor in... i have Whiteline springs (for now, planning on coilovers soon) , whiteline adjustable sway bars front and rear.....

I live in bristol ,TN . Home of Bristol Motor Speedway and Dragway.... racing here is pretty big but mostly straight line stuff.... but there are alot of us who go to the mountains almost everyweekend and run the mountain (US Highway 421) . Thats what i want my car for . . a lil of everything.... sooooo.... Is the extra weight gonna kill the handling of my car??? ive heard its only like 80lbs but with Syko mounts or Mckinney , will it put that 80 lbs where it wont be noticed????

::Thanks for taking time to read this thread and hopefully reply.... ::

[Darius]

You won't notice it once you get coilovers.

[Drftwell]

Which mounting system Syko , Mckinney , or other , would position the weight where it needs to be???? Also im concerned about revving.... whats the capability of the Rb25s with some head work, cams, springs, retainers???

[Darius]

The engine is so long that there's not much room to move it forwards or back. They all put it in the same place so it lines up with the shifter hole.

I'd go with syko or mckinney for mounts and get a custom driveshaft. I have tophat mounts and my transmission mount is bending from the torque or weight, one or the other. Seems too wimpy to me. I need to learn to weld up a new one.

Revving is for V-TACH!! Unless you have a boat load of money to spend on head work and have high power goals (500+), you won't benefit much for the money. Spend the dough on fueling and turbocharging. The RB25 head flows well enough for what you'll probably shoot for.

[Joe]

for years...and years....i have tried to fight the weight balance bull**** myth. years...

the only people who say it hurts the handling of the car, have never driven a RB powered 240.

yes it does affect the handling, but its just a new characteristic of the car. no better or worse. just something you have to adapt to. I had a RB25 in my car for years and did both grip and drift with it, relatively successfully, and i never had an issue with the "balance"

bottom line is 99% of the people who talk **** about weight balance and how they want a "perfect" 50/50 ratio will never drive their car hard enough to notice a difference.

i love using this analogy because its the most cut and dry one i can figure out. your cars balance changes as much with an empty vs. full tank of gas, as it does with a RB25 swap.

[bumblebtuna]

true dat...

14 gallons of fuel weighs what? 100 lbs

[Joe]

14 gallons is ~120lbs

[otis]

for years...and years....i have tried to fight the weight balance bull**** myth. years...

the only people who say it hurts the handling of the car, have never driven a RB powered 240.

yes it does affect the handling, but its just a new characteristic of the car. no better or worse. just something you have to adapt to. I had a RB25 in my car for years and did both grip and drift with it, relatively successfully, and i never had an issue with the "balance"

bottom line is 99% of the people who talk **** about weight balance and how they want a "perfect" 50/50 ratio will never drive their car hard enough to notice a difference.

i love using this analogy because its the most cut and dry one i can figure out. your cars balance changes as much with an empty vs. full tank of gas, as it does with a RB25 swap.

With all the research i did on rb 240 swaps, i always read that it is such a huge difference, untill i bought an rb25 240. granted it has stiff coilovers but going around tight corners isn't a WHOLE lot different than my fd rx7. like kamin said, unless you do some serious cornering or drive your car hard enough then youre not really going to notice much of a difference.

[Adrian gt]

i'm not going to lie, it changes the car, odes it change a lot? not that much, i do like the response of the sr in the car but that also has it's draw backs like understeer. for the most part it will reduce handling a little but af for the whole 50/50 thing, that's for people who can't tune suspension. look at mid engine cars they are never 50/50 but they handle great. same can be said for the rb in a S13-14 might be a little nose heavy but you'll learn to drive the car and some drifters like the heavier nose for stability in the front while the back's out.

[Joe]

i'm not going to lie, it changes the car, odes it change a lot? not that much, i do like the response of the sr in the car but that also has it's draw backs like understeer. for the most part it will reduce handling a little but af for the whole 50/50 thing, that's for people who can't tune suspension. look at mid engine cars they are never 50/50 but they handle great. same can be said for the rb in a S13-14 might be a little nose heavy but you'll learn to drive the car and some drifters like the heavier nose for stability in the front while the back's out.

ok in your sig is says soon to be rb powered. sooo do you own a rb powered s chassis right now while you make those claims?

[FAST-DATSUN]

Wiith a good set of coil over it easy to get the W/B back to stock W/B Its NO big deal. We build many drag/drift and road race cars and there all fine and FAST. even with good stock springs and shocks only the BEST drivers can tell the differance...

[l0nestar]

Honestly, There are very few people around here who can TRULY tell the difference in weight distribution. (and not just 'think' they notice it, but are experienced with corner-weighing and suspension tuning) Of those people, I'm fairly confident that they would be able to alleviate the issue, or easily adapt to it.

I too get tired of this issue being brought up.

[Darius]

I know a guy locally that has scales so I am hoping to see him around again and maybe convince him to help me corner weight my car.

[Abdo]

1993 Nissan 240SX fuel tank capacity: 15.9 gal.Density of gasoline: ~6.3lb/galMass=Density x VolumeMass=(~6.3lb/gal)(15.9gal)Mass=~100.17lbs15.9 gallons of gasoline weigh roughly 110.17lbs.

14 gallons is ~120lbs

So, 14 gallons of gasoline do not weigh 120lbs, silly. 14 gallons of gasoline weigh roughly 88.2lbs! Sorry guys, I'm taking chemistry this semester.
Modified by Abdo at 2:39 PM 10/2/2007

[Joe]

the sites i looked at say 8.6 lbs/gal, but i guess they are wrong.

[Darius]

Ok let's not get wrapped up in the details. Just equate it to a dead hooker in the trunk. DONE!

[Coolwhip]

I feel like pulling out the sock jokes but... oh what the hell.

I have yet to see that too much heavy cotton used in the toe portion on the rb socks throw off the equalibrium of the wearer. k, that's all.

[digzsublime]

No noticeable difference under normal to moderate driving. At the limit, there is a little diference. But, like Darius said, you won't notice once you get coilovers. Yes very experienced drivers can tell some difference. It's doubtful that you will.

If you're that worried about it, go have it corner balanced. Problem basically solved. Kamin is correct (when is he not ). The slight difference is something you adapt to. No biggie. Adjust your driving style and your golden. That is assuming the you can even tell any difference.

[l0nestar]

Just equate it to a dead hooker in the trunk.

"I've never seen so many DEAD HOOKERS in all my life!"Lord knows I have..

Man, I LOVE that movie..

CoolWhip,Man, we need more of the sock jokes..

[Abdo]

I feel like pulling out the sock jokes but... oh what the hell.

I have yet to see that too much heavy cotton used in the toe portion on the rb socks throw off the equalibrium of the wearer. k, that's all.

yeah, i read that thread, funny stuff.

[Drftwell]

Wow... never thought id get that many replies..... THANKS EVERYONE!

~ About the revving thing.... the only reason i would want the motor to rev a lil higher is because it seems as if it gives you a lil more time to play with the powerband.... but of course that can be solved with the turbo and such.... no biggie...

~ Weight issue: Im not a professional and dont claim to be , but road racing and tearing it up on the mountain is why im building my car... that and i really want to learn how to tune.... sooo..... im gonna give it a shot with the RB25 (Rb26 is a lil too pricey for me... i know i know a 25 isnt cheap but i dont see putting another 1500-2000 for the 26 when i could just mod the 25)

~ Mounting System- I believe im going to go with the Syko mounts.... they look very well designed and i like the whole soft at idle but more of a solid mount under load..... but the only thing im worried about is how they relocate ur sway bar.... will my aftermarket sway still fit??? Also the exhaust elbow that they say adresses the RHD LHD differences... allows me to use an sr20 downpipe (which i already have )

Im not new to working on cars, been doing it since i was old enough to wiggle under a car.... but im new to RB's ... ive always been 100% ka.... but since one of my friends has already beat me to going KA-T.... i wanna do something a lil different.... and no 1 around here has really swapped a 25 in .... (that i know of) and 2: There is nothing like the sound of an I6....

I ordered the RB25det swap DVD (i know i know , but i thought it might help me out somewhere and give me some insight on what i got myself into...) should hopefully be in this week tho...

so the only question i really have left is what should i do to the motor once it arrives?

waterpump

thermostat

oil pump??? (do these go out often? )

Headgasket (i read somewhere not to mess with taking the head off..but that just doesnt make sense to me... who knows what the motor has been thro and why not go ahead and replace it with a mhg and some nice ARP head studs?)

Timing belt

is there anything else????

Thanks once again for all of your help.

[Abdo]

I did not have any clearance issues with the factory sway bar using TopHat Performance mounts, and my AM Performance turbo elbow/down pipe clears the steering shaft just fine. Although a friend of mine, using TopHat mounts as well, had to modify his sway bar in order for the oil pan to clear. Either way it shouldn't be that big of a deal. Worse case scenario you'll have to do some shimming or spacing here and there. Looks like you've got everything covered when it comes to requisites.