DCrosby

So I was down in Torrance, (West Side Alignment) getting my car corner weighted and balanced...

Results for the LS1, PS, AC, Stereo, and Full Interior + Spare... & Driver...

LF 774 lbs
RF 730 lbs
RR 802 lbs
LR 758 lbs

Total 3064 lbs Total; with 3/4 Tank and Myslef ~150 lbs

This makes a front to back weight ratio of 49.1% Front to 50.9% Back weight ratio
and 51.4% Left to 48.6% weight distribution.... Which is pretty much what stock is, ratio wise... and maybe about 200 lbs heavier than stock(with Rotray) with me In it. So the(LS1 / V8) swap netted me about 80 - 100 lbs...

<---- Happy

sereneseven

Did you leave the 50lbs of cross weight in it ? if so why?

DCrosby

Sorry I posted Wrong... The back two are swapped...

774 | 730
802 | 758

Respectively

scotty305

iTrader: (2)

Those numbers look great, especially if you had a full tank of fuel.


For reference, my car (1994 base model with stock rotary engine) weighed 2805 with a 143lb driver, about 40% fuel level, spare tire, jack, a/c, p/s and OEM stereo (tape deck, not the Bose system). My weight reduction mods are removed cruise control, downpipe, and odyssey pc680 battery.

My corner weights (in above configuration) were:
767 | 672
709 | 713


-s-

slo

iTrader: (1)

Is that weight with the mods listed below?

It looks like the LSX car is about 250 pounds heavier.

KaoticFdR1

2 different models too...it'd be better to compair the same car.

phoenix7

ok, so the argument about the weight distribution got creamed in the face. What about braking distances and the overall handling of your car? I'm interested to see how your car compares in these fields with the same model FD but rotary powered.

slo

iTrader: (1)

The argument about weight distrabution was never very valid for an LSX conversion on an FD.

Just out of curiosity sake I am interested to know the weight of the components in the most coimmon configurations:
Weight of a t56 + LS1 with intake through headers/manifolds fully dressed VS weight of 13b-rew + mazda trans Fully dressed engine with intercooler and intake less dowpipe, VS same criteria for a 13b-rew with single turbo vs same criteria for 20B with single and twins.

gnx7

iTrader: (10)

A fully dressed LS1 with accessories, harness/PCM is around 480lbs. A T56 is about 140lbs.

My old car's stats (rx7what now owns it):
Touring model, no stereo, no a/c or p/s, no front bumper crash support brace, alum dshaft, heavy dual 3" exhaust with cats/Xpipe/2muffs, and Odessey PC80 mini battery up front.

During corner weighting I was running 18x10.5" CCW's and 285/30/18 Michelin Pilot Sport Cup tires with a full tank of gas. Added R1 strut tower bar and billet alum Rotary Extreme rear strut tower brace/race harness footing point (rather heavy). Also stock passenger leather seat and driver seat is a Sparco EVO fixed racing seat.

2800lbs total (no spare/jack/rear carpet/storage bins/divider)
.4993% front l690 r708
.5007% rear l712 r690

With me in the car: 2943lbs
cross weights 1471/1472 (this is about perfect to be within 1lb of each other)

748/711 49.57% front
760/724 50.42% rear

This car pulled 1.13g's at the SportCompactCarMag "USCC" event tested on a 200ft skidpad and won that category. It also placed 4th on the road course (out of 11 cars and 8 professional drivers) with me driving with brakes that locked up and my 1st time ever on that course. I'm sure it could've done better. So the handling I would say hasn't been altered much if any at all.

http://www.v8rx7forum.com/v8-rx7-tec...tio-93-fd.html

phoenix7

GNX7! Have you always been in this section? I haven't seen you on the other parts of the forum in a long time. What happened to your LS FD (the white one you had a while back)?

It looks like the extra weight doesn't negatively affect the handling. You were able to lock the brakes which means that your brakes are still able to stop the car but were the stopping distances longer or about the same?

gnx7

iTrader: (10)

I had a white GN powered FC at one point.... but only silver FD's.

Sold the LS1/FD (silver) to rx7what and I'm building an LS7/FD now.

phoenix7

you had that painted FD in white and the LS motor in your garage. I could have sworn it was white.

2MCHPWR

iTrader: (2)

for comparison, i'll give you my LS1 FD, as well as a friends stock rotary. both with no driver, no spare, stock wheels and 3/4 gas tank approx.

my FD LS1 with no PS, no AC, no ABS:
Left Front lbs. 684
Right Front lbs. 695
Left Rear lbs. 705
Right Rear lbs. 645
Total Front lbs. 1379
Total Rear lbs. 1350
TOTAL Weight 2729
% over Front 0.505
% over Rear 0.495

My friends stock 93 R1:
Left Front lbs. 718
Right Front lbs. 718
Left Rear lbs. 660
Right Rear lbs. 618
Total Front lbs. 1436
Total Rear lbs. 1278
TOTAL Weight 2714
% over Front 0.53
% over Rear 0.47

I have to get it redone since i've made changes since then:
-installed ABS
-installed PS
-sparco drivers seat
-coilovers
-SSR wheels (fronts weigh approx same as stock but rears like 1.5 lbs more)

gnx7

iTrader: (10)

Always silver.

I road raced the car with a non functional ABS. 13" AP brakes up front and '99 RZ out back. Fronts would lock up like a mother if I stabbed the brakes. Flat spotted a set of $300 tires..... not good. If I depressed the brakes gradually they worked well.... but not superb if the ABS was working.

slo

iTrader: (1)

I had an rew shipped to me fully dressed minus clutch cover, oem precat/downpipe (which is really part of the exhaust not the engine) intercooler and air box (don't weigh much anyways) the total shipping weight was 420# including a pallet that was easily 50+#s.

so around 380 pounds for a fully dressed REW engine. It's supprising how heavy all the manifolds and accessories are on this engine, with everything stripped down the "short block" is under 200 pounds.

CR500FD

the LS1 has a higher CG, that is rarely discussed and will effect turn-in

phoenix7

I have notice that too. The motor sits much higher than the rotary. I watched a vid with an FD at the autocross and the guy was understeering at the corners and he had to power himself out of it. He might have sucked a little but I WAS wondering how turning was affected by the higher center of gravity.

2MCHPWR

iTrader: (2)

yeah you guys are so right. my car handles horribly!!! I'm so slow! so many cars beat me! I'm so dumb! All my rotary friends shun me and don't like my car and beat my car on the track all the time!

paul_3rdgen

iTrader: (6)

How do you figure?? An LSX motor has a lower CG figuring the crank is at the lowest point of the block right before the pan, can you say the same for a Rotary? Also the LSX block is aluminum, and the heads are aluminum. The rotary on the other hand is made up of multiple plates, 3 of them being heavy cast IRON plates which don't sit at the bottom of the motor but from top to bottom of it, also right in the middle of the motor are not so light Rotors. An LSX motor has aluminum pistons which weigh a fraction of those 2 rotors.

Have you ever driven an LSX FD??? I have owned my car for 9 years and tracked it with both setups, Rotary and LSX swap, which is better? I like them both, but would I say the turn-in was effected? NOT AT ALL!

Be informed and educated before assuming the worst.

DCrosby

+1

Me too... man... God what have I done ??? My Turn in is all 'Fd up.... Somone help me swap my apex seal eating rotary back in... so I can salvage my turn in's.....


BTW: Went to dyno this last weekend... wanted to see Steve Kahn, and tell him how "Upset I was about my turn in's" and he put the car up on the dyno... with just the shitty (untuned) stock tune from Hinson, and made 300 RWHP, which isn't much... but that's Un-Tuned... with as I recall 11.7 AFR's under WOT... and I think he said some very "safe" advance.... for now... more HP than I can put to the asphalt... with my 8" rears.... -> Soon to Change

phoenix7

I guess you're racing 700hp novas if you think your LS FD is slow. Post engine pics please. I wanna check out how you mounted the motor and if there are differences in the way the motor is installed in one 7 and another.
I knew you guys would break. The couple of ppl here that are asking detailed question are doing so out of curiosity. In no way can we consider the higher HP and torque inferior than the rotary (that's retarded). I've noticed that the V8 RX owners are always quick to mention how superior the swap is but once questions are asked they go into defensive mode (like the two posts above by 2mch and Dcros). They're just questions guys, how can we make informed decisions without knowing ALL the details. I know the swap has flaws, it HAS to. But rarely do we get any insight on it. We all know the rotary is finicky and we're all really fast when it comes to pointing them out but I rarely hear the DOWNSIDE to the LS swap ( i refuse to believe this is such an amazing swap that everything is perfect.)

I thought the turning question was a valid one. From what I've seen the motor sits MUCH higher than the rotary motor and I don't know about you but I'm sure it makes a difference in handling if your center of gravity is raised by several inches AND you add 150-200lbs.

2MCHPWR

iTrader: (2)

see my corner weights on previous page. my swap added 15 lbs.
and front / rear weight distribution improved.
get it?

phoenix7

I get it but you're not the only one who's done the swap and your weight is not the avg. for all LS swaps. how much does the PS and ABS stuff weigh? and the engine still sits much higher unless you somehow mounted it super low. I'd love some engine bay pics too.

DCrosby

You want to know drawbacks ???

To me, since everyone's experience is different:

It's a PAIN to do, due to finding the right parts, getting gremlins figured out, finding little things that still need to get done.
It's Loud (My Exhaust configuration has 1 Muffler and two cats)
It has its own set of mechanical / technical issues/challenges with the increase in torque on the driveline, and those forces on the chassis.

Other than that, I've owned 2 FD's, the first was a beauty, both visually and mechanically, and she ran great had great power and I loved driving that car. Then I did something stupid, and wrecked it (My Fault, thank God Nobody got hurt) Then I bought this car, and I've had NOTHING but headache / heartache over this car. From the Motor(s)[2] to the turbos' to the tuning. Had I not done the swap I would have had to sell a rolling chassis at a significant loss... this was a last ditch effort to keep the car, and stop the hemorrhaging...

(Why did I tell you this?)

I've never been happier with my car, incl. the Orig. 7 than I am Now.. and the only thing that sucks when I drive is I'm scared to screw it up... or have someone plow into me. Other than that it's Bliss !

As far as the Handling goes, it's tough for me to tell since I'm not a professional driver, and the rear in the new car has always been tail happy, I get very little "Warning" that the rear is going to let loose, but that wasn't any different in the rotary days, when it did run... so as far as "Handing" on the autocorss I personally didn't feel any difference, other than I had to really watch what power inputs I gave when... due to the increas in tourque... I had someone else with a stock FD drive the car with me in it and he said it felt different due to the non-stock suspension but didn't feel front or tail heavy.... and this was the guy who invited me to the autocross...

You're probhably right it changes things under the hood... but not that I can tell, and that's all I care about... your milage/experience may vary....

This is the autocross I was refering to, with me in the passenger seat with matching helmet

wptrx7

You do realize in most of your post you didn't ask questions, but implied what you thought were flaws without really even knowing. If you really want to know or learn, visit v8rx7forum,com and swapcartech.com. Don't post, just read. There is plenty of information to be found.

Most guys ow are past the point of the actually installation and weight issues, they are now on how can they put the power down.

Luigi