S30 w/L28ET running 12.60s?

[letitsnow]

My '77 weighs 2740 with me in it, I weigh 175ish.

[BLOZ UP]

My '77 weighs 2740 with me in it, I weigh 175ish.

 

L series? Mods/reductions?

[letitsnow]

Yup, turbo L, steel IC pipes, no bumpers, no AC in the engine bay(still under the dash), no spare or tool kit, coilovers, 16x8 xxr 513's. I'm probably forgetting a few other things, but that's most of the weight changes.

 

I've weighed it on two different scales, one at the drag strip, and one at a gravel pit.

[Tony D]

Yep, the late S31 series cars (75-78 280Z's) weren't light. The 79 Standard ZX was actually a lighter car!

But the weight got packed on fast in the ZX.

 

My 1976 FAIRLADY Z 2/2 weighed in at SanAntonio Dragway with 255# me inside it at 2695#, putting the car at 2440# without me and a full tank of gasoline.

 

If it's 2965# (as some have suggested) then I have a 200+ RWHP Stock L28 because the car was running all night long (26 passes in all) at 15.50-15.60 at 88-89+ mph...

[BLOZ UP]

Yep, the late S31 series cars (75-78 280Z's) weren't light. The 79 Standard ZX was actually a lighter car!

But the weight got packed on fast in the ZX.

 

My 1976 FAIRLADY Z 2/2 weighed in at SanAntonio Dragway with 255# me inside it at 2695#, putting the car at 2440# without me and a full tank of gasoline.

 

If it's 2965# (as some have suggested) then I have a 200+ RWHP Stock L28 because the car was running all night long (26 passes in all) at 15.50-15.60 at 88-89+ mph...

 

Yeah, but I thought they were a little heavier. 27xx isn't that bad. I'm very curious what mine is at with the VG. Guess I'll have to get it driving to find out.

[SleeperZ]

I may have remembered my car's weight incorrectly, it's been 7 years since I drag raced. I have full interior, no cage, and the crash bumpers are removed. It is probably around 2700lbs without me in it...

 

Good thing too, as not long ago I was messing with the remote starter and rolled the front tire over my foot. No damage.

Edited December 7, 2011 by SleeperZ

[78 LS2 Z]

There's no way you were making 400rwhp and trapping 104. 300rwhp in a camaro will trap 105-110 pending weight etc. 400 will put you high teens. That S30 was probably making 250ish rwhp.

 

I ran a 13.4 at 101 on my first(and only) pass of the night, on stock boost(with IC, exhaust, and MS). 12.60 is entirely believable for a modded, stock turbo, L28ET at higher boost.

 

The car could be heavier than he thinks..I would have to agree that the mile per hour is down quite a bit for 398 RWHP and 3500 lbs. Ideally, the ET should be in the 12 flat range at 111-113 mph. So, if the chassis dyno was accurate, this car weighs more than he thinks....I'm not doubting he made 398 HP, but something else is going on to get that low a MPH. That MPH suggests a much heavier car, over 4000 lb....

[seanof30306]

The car could be heavier than he thinks..I would have to agree that the mile per hour is down quite a bit for 398 RWHP and 3500 lbs. Ideally, the ET should be in the 12 flat range at 111-113 mph. So, if the chassis dyno was accurate, this car weighs more than he thinks....I'm not doubting he made 398 HP, but something else is going on to get that low a MPH. That MPH suggests a much heavier car, over 4000 lb....

 

There is a lot more going on in ET than HP and weight.

 

First, torque has a lot more to do with ET than HP.

 

Second, gearing and traction are major factors, as well. If you're not hooking up on the line, and you're having to feather the throttle in 2nd gear, you're moving, but you're not accelerating efficiently, and that will all reflect in the mph on the other end

 

If you go back and read my posts, you'll see I was

 

a) Running true street tires, not drag radials

 

Running a 3.42 gear

 

c) Shifting into 4th gear at about the 1,000 foot mark

 

d) And it was over 90 degrees out

 

And the weight is correct. At the time, I weighed about 250 lbs. The car weighed 3763 lbs on the scales at the dragstrip, with me in it, and 3/4 tank of gas. That makes it a 3500 lb car.

 

I was quite happy with the performance of my car. Anytime I can drive a Gen I small block powered car 100 miles, get 26 mpg, cool it off for 20 minutes and crank out high 12s in 90+ degree heat with no power adders on street tires, I think that's pretty cool.

 

I have no doubt that, with a 3.73 gear, and 30" tall drag radials, I would have been running at least low 12s in the 115-120 mph zone. The torque was definitely there to do it. That's not the way I wanted to go, though. I was fully aware that I had more engine in there than the setup at the time could handle, and I was OK with that.

 

Aside from the fact that there's no way you can accurately associate ET and weight with mph without taking multiple other factors into account, what I can't understand is why we have to spend all this time going off-topic. What my car ran is only relevant here as it relates to what the L28ET-powered S30 ran against it. This discussion is over what the S-30 ran.

Edited December 7, 2011 by seanof30306

[78 LS2 Z]

Dude, your ET tells you how well you hook up and drive the car, that's all. MPH tells the story for a car's power, period. MPH doesn't care about traction, etc....That being said, my statement that the MPH is low for that power and weight is correct. Nobody cares what a car weighs without the driver. The weight of the car with you in it is how this is calculated, unless you plan on driving it remotely. Nobody is bashing you or your car, the MPH just looks low. YOU are the one who opened this can of worms with your opening statements, so bash yourself for running off your own topic!

[letitsnow]

In short, I'd be suspicious of that dyno in the future, I trust scales more than dynos.

[jc052685]

I think there are some guys on the forums here running high 11's with only high 300 whp setups. Keep in mind, an L28ET that makes 350whp will probably have around 400ftlbs, or more...

 

At 274whp I ran an 11.80. Since then the car made 334whp/384wtq, have not made it to the track on that power. Car with driver weight full tank - 2460lbs

[Gollum]

Some much need Datsun data this thread lacks, and not for the lack of knowledgeable people in this thread. My bet is that they just don't want to spoon-feed, which I don't mind at all.

 

 

The 3.9 that LS powered S30 you saw at the track was probable an open ended diff. Major problem when you're pushing 400+lbs through how much tire that guy had.

 

If the suspension wasn't sorted, then that's a HUGE deal in a V8 powered S30 Z car (S30 = '69-'78 USDM Z car typically). Putting a V8 in can shift the weight balance a TON. There's a million things that could be done to help that car corner better and put it's power down. Sounds like he probably also could have fixed the issue with a simple wing. Those three things (diff, wing, suspension/chassis tuning) could have really transformed that car.

 

As I'm sure we all know, it takes more than just power to go fast on a road course/auto x and you can't blow your budget wad on your engine alone. There's plenty of people putting down crazy track times in the S30 with a V8. It's not impossible at all, and it only takes the same work it takes to setup any car, just different specifics.

 

Regarding running 12's in a stock L28ET powered S30, totally doable. Really all the guy needed was a manual boost controller ($5-30) and a rising rate fuel pressure regulator ($100-200). Done. Done. And Done. At 2400 pounds 250 wheel HP should get you into mid 12's easy. That'll only take about 12-15psi from what I've seen in several occasions. Add an intercooler for safety, especially if you're not running race fuel or if it's a warmer climate. As long as you're running it pig rich up top with the RRFPR then detonation shouldn't be too big of a deal with race gas. I wouldn't run more than 10psi on the street with less than premium without an intercooler.

 

Why don't more people do it? Big thing is that it's not what these cars are known for. In most racing circles the 240Z is seen by MOST people as a V8 swap recipient. Even I got into these cars 10 years ago because of a V8 swapped one I saw in person. Today I own a L28ET powered S30, but I'd been just as happy with a V8 in mine.

 

The next reason it's not as common is lack of information. People like an easy to fallow guide, and that's plain for the V8 swaps. The L28ET swap is usually done by people that already know what they're doing and what they want, because it's less popular, so the documentation just isn't done as often. The lack of information also extends into performance value. Most of us that have taken the time know that we can get 300hp at the flick of a finger with these motors, yet we get people on this forum constantly asking "how can I get 300hp out of a L28ET?".... Seems like many people on this forum are asking themselves (not publically on this forum of course) "how do I get 600hp out of my motor?" We have people here who've made that and more to the wheels, yet few people know because you have to be looking for this information to find it. It's not just out for all motor heads to find out.

 

Then there's cost. Some can get a longblock for $300-500. Others search locally for months without finding a longblock for less than $1,000, and at that price I'd just go with a V8. The prices are highly volatile due to location of the country, who has it and what they know about it, and what fanboys in the area have done to the local market. I sold my last motor for $500, which was cheap in my area but I was selling it to a friend.

 

 

Now, onto weight. The S130 ('79-'83 280ZX) weight fluctuated a lot, as Tony pointed out. My '81 Slick top (BIG weight deal) comes in at 2700 with full interior, bumpers, AC, etc. When I weighed my '75 280Z it came in at 2460. It had no bumpers, no carpet, no stereo, no intercooler, no AC, semi-rust lightened. I have no doubt that trim for trim the S130 isn't heavier than the S30. The main issue comparing is that most S130's came WAY more trimmed than most S30's. The T-Tops add quite a bit and the entire top is heavily reinforced to boot (big square crush channel running the length of the roof and an extra later of metal in the side pillars). Many more of them had power windows. They had bumpers more similar to the later 280Z bumpers.

 

Find a slick top S130 and remove the bumpers and other stuff that most S30's don't have and you'll have a 2400-2600 pound vehicle depending on how you're spec'ing it out, weather to compare a minimal bumper and feature 240Z, or a full featured late 280Z.

 

Getting to the point of the fact you know someone running 15's in a S130, well I think a bit of that could be driver, or an issue with the setup. Auto or manual? Good clutch? Shifts? Even at a mid-range S130 weight of 2850 and what I've seen those motors produce stock it should be knocking on the door of 14's easily enough with a clean run. Either it's a fairly heavy model with a bone stock engine, or it's lost a few horses from various issues, which is completely possible. Find out what the car with driver really weights. Unless the car is 3200 pounds with the drive then there's something either wrong with the driver, or the car.

 

If it's just weight (which is entirely possible) and the engine is running well, then this owner could be in 13's with minimal mods. There's no excuse not to do some of these mods unless the owner just doesn't care (which if he's going to the track I'd imagine he cares.)

 

1. Boost controller (keep it under 10psi without other mods)

2. Add intercooler (can run up to 12psi now but will be dangerously lean up top)

3. RRFPR (if it's an adjustable ratio then tune it on a dyno and you can now run it up to 15psi in most cases)

 

You've now got everything you need to run at least 275whp. Reaching the 300hp mark is doable with just these engine parts, but will take careful attention to details. You'll need more pump most likely, and to make sure you're running quality gas and that your fuel pressure tune is stable and accurate. But it's doable.

 

To make the 300hp easier to hit, you'll want to add larger injectors and a tuneable ECU. Ditch the dizzy for something crank triggered and you're even better off. A better turbo would also be a good idea as the stock T3 will be WAY out of efficiency and will be working against you. 300hp is probably actually more than it's rated to support. A T3/T4 hybrid will work well, and you'll see quite a few people that switch to the Holset turbos. Both of which won't break the bank if it's not a special ball bearing variant.

 

All this is a lot more attention to details and harder to find concrete info on than building a 300hp SBC, SBF, LSX, or anything else over 4 liters really. I think that's why we're not seeing the L28ET catch on faster. But it HAS made leaps and bounds just in the 7 years I've been on this website.

 

Hopefully that answers some questions and gives some insights that might not have been readily represented earlier.

[SoC MATADOR]

WOW... Can't wait to get mine runnig. And one of the reasons i went with the L28ET was because i met a guy with a really nice 240z that had it built to crazy specs, and it's a lot more unique than a V8 swap.

[seanof30306]

Dude, your ET tells you how well you hook up and drive the car, that's all.

 

Ridiculous. Your ET tells you how quickly you go from a standing start to breaking the lights 1320 feet down the track.

 

A large portion of how well you drive the car concerns your reaction time, which has absolutely nothing to do with your ET, or the MPH you run on the big end.

 

Most of the rest of how well you drive the car goes into the launch. After that, a trained monkey could do it. Hell, if you have a properly set-up automatic transmission, it'll shift for you, taking almost all of the skill out of it fter the launch; certainly after the 1-2 shift.

 

MPH tells the story for a car's power, period. MPH doesn't care about traction, etc....

 

Utterly ridiculous. At it's heart, drag racing is simply an exercise in torque multiplication. In the 1320 feet you have to work with, you will arrive at the highest MPH through the most efficient torque multiplication. If you spin the tires at launch, spin the tires through 1st and 2nd gear, or have to limit throttle to keep from spinning, you are using up some of those precious 1320 feet multiplying your torque inefficiently. The most efficient multiplication of torque would be to floor it at the green light, not lift all the way down, and have no wheelspin. Anything less than that is inefficient torque multiplication, and that lost multiplication of torque cannot be recovered. As a matter of fact, since you are multiplying torque, the further down the track we go, the greater the negative effect of that poor launch/wheelspin will be on the MPH you ultimately reach.

 

That's why you will always see not only a decrease in ET, but also an increase in MPH when the 60' times improve (unless you run out of gear and nose over before the finish line).

 

I will absolutely guarantee you with a set of drag radials or slicks that were the exact same height as the street tires on it, the 60' times and ETs my Formula ran would have gone down significantly, and the MPH would have gone up significantly, too. Since the tires are the same height, the gearing would remain the same, so the only factor that would change is the traction.

 

Drag Racing 101, dude. Before you go lecturing someone, you ought to know it.

Edited December 8, 2011 by seanof30306

[seanof30306]

Some much need Datsun data this thread lacks ........ Hopefully that answers some questions and gives some insights that might not have been readily represented earlier.

 

That's a lot of information. Thanks for taking the time to share it with me. I wonder if it would make sense to compile additional information with that for the FAQs?

 

As far as the 3.9 in the LS240, it was definitely an LSD. Both wheels were pulling, and the guy told me it was a limited slip when we were talking about it. He went through his suspension mods with me, but I don't recall what they were. Regardless, they could not have been dialed in properly, or poorly matched. He said he was an avid autocrosser and track day enthusiast, though, and said the car handled very well before the swap. My opinion, albeit based on incomplete information and low expertise on Z-cars, is that he was overpowering the tires. The LS2 crate motor he was running made over 400 ft lbs of torque. On a car that light, with that small of a tire, and that much gear, I don't think any amount of suspension work will make that rear end stick on an aggressive corner exit. V6 Camaros have significantly more tire under them than that S-30, and nearly 1500 lbs more weight to plant the car.

 

I guess I'm sensitive to this because of my experience with my Firebird. With the near-stock L03, which made 170 ground-pounding HP, and 253 ft lbs of stump-pulling torque, I consistently ran 2.0 60' times, and it was a blast on the autocross courses. On the track, it sucked on the straightaways, but it was controllable in the corners, and fun to drive. After the 383, my 60' times never improved significantly over that 2.0 mark, and were sometimes worse. The autocross was a nightmare, and while it was more fun on the straights at the track, exiting corners sucked. The "sweet spot" was now razor thin, and even after the corner was behind me, it would still sometimes break the tires loose in 2nd, even 3rd gear. Before the 383, I could drive the car pretty close to it's limits. After, it's like trying to get along with your girlfriend after she finds your porno stash on your computer; the slightest misstep and it's rage city. My Firebird turned much faster laps with the 383 than it did with the 305, but it was nowhere near as much fun to drive. I think I would have enjoyed the car a lot more if I'd done a 350 that made around 325-350 RWHP and under 400 ft lbs torque. That would have been a power level that was more in line with the suspension and tires I had under the car.

 

As I was following that S30 around the track that day, the first thing that occurred to me was "That thing is worse off the corners than my car!".

 

It's what made me really rethink the LSX idea.

 

Having owned both a V8 and an L28ET S30, can you compare your experiences/impressions of the two?

Edited December 8, 2011 by seanof30306

[78 LS2 Z]

Ridiculous. Your ET tells you how quickly you go from a standing start to breaking the lights 1320 feet down the track.

 

A large portion of how well you drive the car concerns your reaction time, which has absolutely nothing to do with your ET, or the MPH you run on the big end.

 

Most of the rest of how well you drive the car goes into the launch. After that, a trained monkey could do it. Hell, if you have a properly set-up automatic transmission, it'll shift for you, taking almost all of the skill out of it fter the launch; certainly after the 1-2 shift.

 

 

 

Utterly ridiculous. At it's heart, drag racing is simply an exercise in torque multiplication. In the 1320 feet you have to work with, you will arrive at the highest MPH through the most efficient torque multiplication. If you spin the tires at launch, spin the tires through 1st and 2nd gear, or have to limit throttle to keep from spinning, you are using up some of those precious 1320 feet multiplying your torque inefficiently. The most efficient multiplication of torque would be to floor it at the green light, not lift all the way down, and have no wheelspin. Anything less than that is inefficient torque multiplication, and that lost multiplication of torque cannot be recovered. As a matter of fact, since you are multiplying torque, the further down the track we go, the greater the negative effect of that poor launch/wheelspin will be on the MPH you ultimately reach.

 

That's why you will always see not only a decrease in ET, but also an increase in MPH when the 60' times improve (unless you run out of gear and nose over before the finish line).

 

I will absolutely guarantee you with a set of drag radials or slicks that were the exact same height as the street tires on it, the 60' times and ETs my Formula ran would have gone down significantly, and the MPH would have gone up significantly, too. Since the tires are the same height, the gearing would remain the same, so the only factor that would change is the traction.

 

Drag Racing 101, dude. Before you go lecturing someone, you ought to know it.

 

 

 

There are many variables that ultimately effect your exact mph. You may get some minor variance with the factors you mention, but a general rule of thumb is that MPH does give a good indication of the power a car makes. If the car is consistently at the same MPH through the traps then you can predict power. If the MPH is consistently down then there is more weight or less power than you think. This is simple math. Maybe you skipped math class when you were taking Drag Racing 101...The MPH is low given the weight of the car and the power you state the car makes, that can't be argued and that is my point. I'm not talking about spinning off the line or any of these factors you mention, I am talking about repeatable, consistent runs to establish a MPH average.

[seanof30306]

There are many variables that ultimately effect your exact mph. You may get some minor variance with the factors you mention, but a general rule of thumb is that MPH does give a good indication of the power a car makes. If the car is consistently at the same MPH through the traps then you can predict power. If the MPH is consistently down then there is more weight or less power than you think. This is simple math. Maybe you skipped math class when you were taking Drag Racing 101...The MPH is low given the weight of the car and the power you state the car makes, that can't be argued and that is my point. I'm not talking about spinning off the line or any of these factors you mention, I am talking about repeatable, consistent runs to establish a MPH average.

 

Interesting that you should mention math, as that is essentially what I do.

 

Regardless, here is the inescapable fact of the situation.

 

Take two identical 3500lb cars, both making 400 RWHP and 435 torques. Identical HP and torque curves.

 

On one, put 29" tall slicks and 3.73 gears.

 

On the other, put 29" tall street tires, and 3.42 gears.

 

Line them up side by side, with drivers of equal size and skill.

 

Barring a mechanical failure, or driver error, the car with slicks will have a significantly lower 60' time, a significantly lower ET, and a significantly higher MPH every time.

 

All of the reasons for this were explained above.

 

Torque

 

Multiplication

 

 

 

 

 

 

Look into it.

[letitsnow]

I've run low 12's at 109, I've spun BADLY(think 3 sec 60' times) and run 15's at 105. You can take much longer over the first 50 feet and lose lots of time, but the car has nearly the same length of track to accelerate up to a similar speed.

 

A 400rwhp s30 will trap 125 on a good street tire with 3.54 gears.

[Gollum]

Having owned both a V8 and an L28ET S30, can you compare your experiences/impressions of the two?

 

I've not owned a V8 S30, but I have driven a few and hopefully my input will suffice for the time being.

 

It really comes down to goals in my mind. You have to define your goals and also application. Where are you going to drive it? Street, track? Racing Class? If you're just taking it to HPDE type events where rules aren't a huge deal then you then just have to deal with what you want out of it. 250hp, 300hp, 400hp, 500hp? What size tire would you like to run?

 

You can fit a 245 easily enough under the stock rear flares, and I can't remember the size, but look up clifton, he fit HUGE tires under the stock well without tubing the rear. I want to say it was like 265 or even 275. Maybe my memory is failing me. If you're willing to add flares, there's the 17x9.5 group buy rota's which will tuck a 285 under the rear easily enough, just need a good 2" of flare or so.

 

My personal preference for a mainly street car is for the L28ET. I like the dynamics of a turbo motor. People complain about lag of turbo cars, but it's never been an issue for me. As long as you're in the right gear (which you would need to be in a NA car anyways) then lag is never a race breaker. But when you pull your foot out of it the engine calms down and becomes very manageable. In that sense I actually love turbo lag. You can get way better MPG from a turbo versus a supercharger because there's less parasitic loss combined with a larger window to drive in without boost interaction. And the stock T3 still spools crazy fast. I can be lugging around at 25mph in a school zone in 4th gear (3.55 rear diff) and when I exit the school zone just a quick second of throttle stab and i'm in boost and going 45mph... And I think i'm under 2rpm in that scenario.

 

A V8 Z car is a whole different beast. They're fun fun fun fun fun fun fun. No doubt. They're a handful, but they really grow on you. I've driven sub 12 second muscle cars and they weren't anything like a V8 Z. A Z car has a totally different driving feel, and as such I don't mind it being so tail happy with the loud pedal. A V8 is the logical option if you want big HP and want to keep costs down. I really want to build a 500+hp L28ET, but I also know it's going to cost me as much as buying a brand new Ford Coyote V8, and I'll be doing 90% of the work myself. You can buy a used LSX for much less, add a cam and be done. You can buy a SBC crate motor and be done with a much simpler setup (takes what, 3 wires to get one running in carb application?).

 

I didn't think a whole lot of the L motors when I first got into them, but they've really grown on me. I grew up around hondas and mustangs and have had my hands deep working on all types of engines and despite all the things I really don't like about the L motors they're horribly addictive.

 

Oh, and if you're wanting more than 300hp, your transmission options for the L motor get much more complicated than V8 choices. There's options, they're just not super easy and available.

 

All that said, I think 300hp is a really sweet spot for the S30 chassis. It's going to act like a monster with how light it is, and you can still fit enough tire under there to make it work well enough. I know you're quite torque conscious, but in the end all torque represents is HP curve. HP is what moves a car, and "high torque" is just synonymous with "broad power curve". I love torque, I'll always prefer one option over the other if the HP are the same but torque is higher on one motor. That said I also understand it's about curve length too and all that jazz. Point to all this being, is that the L28ET is going to have nearly the same, if not more, torque for a given HP range than a V8, it's just not going to come on so instantly when you hit the pedal. At 300hp, you'll have around 350lbs. It's going to be able to light the tires for sure.

 

But again, going back to the fact that it's not all as bad as you think, check out darius's car. Supercharged LT1 with GOBS of power. You'll see in this first video he can romp on it to make the car step out, but he controls it wonderfully. In the second video you'll see him racing a R1 bike, and he's not leaving tire smoke at all, very controlled. And that setup is probably MUCH harder to control than just a stock LS2.

 

http://www.youtube.com/watch?v=-3DlpSE1jsE

 

http://www.youtube.com/watch?v=1DqfNAGFCVU&feature=related

 

Darius also didn't do nearly as much as could have been done to keep it a controllable setup. He could have had much more tire. He could have added a wing. He had hardly any aero work for that matter. I don't think he went crazy on suspension, etc.

[letitsnow]

Clifton fit a 275 out back by carefully picking offset and running a short, stiff, coilover spring that put the perch above the tire if I remember correctly.

 

12 psi on my L28 with the stock turbo will light the tires from a 20-30mph roll if there's any moisture on the road. It really does make a lot of torque for a little engine, full boost can be had at almost 2k in higher gears.