S30 w/L28ET running 12.60s?

[seanof30306]

A couple of years ago, I was running my '89 Formula Firebird 383 stroker at the Atlanta Dragway.

 

As I was waiting in line, I struck up a conversation with a guy next to me with a really nice '73 240Z. I'd always loved those cars, so I was really interested.

 

Someone ahead of us oiled up the track, so we looked each other's cars over as they cleaned it up.

 

He said he'd bought a wrecked 280ZX Turbo and swapped the entire drivetrain over. Looking under the hood, his claims that it was stock seemed plausible to my unknowledgeable eye. I don't recall seeing an intercooler, or even a big CAI. All I noticed was headers.

 

We finally got to the head of the line and ran against each other. I pulled ahead out of the hole, and didn't see him again till he blew by me at around the 1,000 foot mark. I ran a 12.93 at 104 mph. I don't recall his mph, but I'm pretty sure I remember his running in the 12.60s. He beat me by a good 5-6 cars; maybe more.

 

I was blown away by how fast he was, but not knowing anything about Z-cars, I just chalked it up to a really light car and an engine that made A LOT more power than I'd thought.

 

I got to thinking about it again the other day, though, when a friend of mine was talking about an '81 280 ZX Turbo he'd owned. He said it ran high 15s in the 1/4, at best.

 

I can't imagine there's enough of a weight differential between an S30 and a 280ZX to account for that speed differential, is there?

 

If his car wasn't stock, it sure was reliable. The night we ran was in the middle of the summer, and the sun had not yet gone completely down. It was still over 90 degrees out. I lived in Buckhead, and the trip up to Atlanta Dragway was over 100 miles. He said he'd driven over from Greenville, which was a similar distance. In 30 degree cooler temps, after a complete cooldown from the drive up, I ran 12.70s with the same setup. There had to be more in that S30, too. As I understand it, turbos are more sensitive to heat and hot temperatures than naturally aspirated engines, aren't they?

 

I looked this board over, and I see a lot of disjointed discussion over this swap, but no definitive faq or sticky. If getting that fast with a bolt-in factory swap was that simple, I'm surprised everyone's not doing it.

 

At the time, I was making right around 400 RWHP in a 3500lb car. Figure the S30 at 2500lbs, I'd think he'd still need at least 350 RWHP to run that kind of time; especially that kind of mph. He had to be running in the 115 mph range.

 

Can y'all educate me?

 

Thanks.

[CamH]

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...

[letitsnow]

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.

Edited December 5, 2011 by letitsnow

[Tony D]

Yep, a 240Z with some attention paid to weight and a stock L28ET suitably attended to (some more boost, not necessarily an intercooler) is easily a 13 second car. 12's is possible. Very possible.

[Tony D]

BTW, an 83 ZXT can be quite a pig, over 3000# depending on drivers weight...

A 73 240 is not the lightest but with some early model doors and suitably bumpered, 2400 is pretty easy to do.

My Full-Weight 73 240Z was a pig with my swinish countenance in it, and 100+ in the 1/4 was not difficult at all without an intercooler and some basic old-school tweaks.

The ZXT the donor engine came from seemed to struggle to break 80-85 before the swap. The 240 was alive compared to the ZXT. and it came further alive once I got the 3.70 into it later on... The 240 still had the 3.36 gears at that time!

[seanof30306]

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.

 

My Formula made a best of 398 RWHP on a DynoJet 248c chassis Dyno at DynoLab in Marietta, GA. On the day in question, after having driven over 100 miles in 90+ degree heat, and after only a 20 minute cooldown, it ran a 12.93 at 104.23 mph. The time and mph were relevant because that was the run the S30 smoked me in, and he was clearly going 10-20 mph, or more faster than me when he motored by.

 

Later that night, after a cooldown of over an hour, in temps over 20 degrees cooler, I ran my best run of the night; 12.78 @ 109.7.

 

The best run ever occurred several months later on a 70 degree night; 12.48 @ 114.35 mph.

 

That was with real street tires, 3.42 gearing, and shifting into 4th at about the 1000 ft. mark.

 

There was more in the car, but only with drag radials, or slicks, which would have both lowered the 60' times, and increased the mph. I wasn't interested in that, I built the car to run as I drove it. With over 450 lb ft torque, 3.73 gears would have just smoked the tires. I was quite happy with the way it ran.

 

Getting back to my original line of questions, then, if you can get that much out of a near stock L28ET, then there should be a lot more there, and since it's essentially a bolt-in, I'm surprised to see so many LS swaps.

 

Don't get me wrong, I'm a big fan of the LS engines, but with the limitations on tires you can get under the car without running flares, Even a mild LS will overpower the car. Wouldn't it be simpler to lean on an L28ET a bit harder, rather than going to the expense and effort of going with the LS, especially if you didn't want to flare the fenders?

 

I've liked the idea of going with a LSX for some time, but this summer, my concerns appeared to have been confirmed by a guy at the road course here in Tulsa. Well, near Tulsa, it's actually in Hallett, about 45 minutes West of here.

 

Anyway, he had a beautiful S30 with an LS2/T-56 swap. Everybody there was marveling at it, the workmanship was beautiful. I caught up with him out on the track, and followed him for a few laps. The car was a pig. Every time he gave it the gas when exiting a corner, the rear end stepped out. He'd still be feathering the throttle 50 yards down the straightaway. I figured he just didn't have the suspension sorted out yet, but talking to him in the pits, he said the car used to handle perfectly before the swap. If I remember correctly, he said he had 17 x 8 or 8.5" wheels on the car, with not much tire. He wasn't going to cut or flare the fenders, so that was all he had to work with.

 

Driving back to Tulsa, he pulled up beside me at around 70 mph and nailed it (without dumping the clutch). The car fishtailed for a good 10th of a mile before he let up on it. We stopped for gas a few miles later, grabbed a couple of Cokes and shot the BS. He said he was running a 3.9 geared R200!

 

*** Question for LS swappers: Why do so many of you run so much gear? I see all these youtube videos of LS Z-cars at the dragstrip, and they're all over-geared for street cars. If you have to shift your street car into 2nd before you get off the concrete launch pad, you are running too much gear! The T-56 has either a 2.66 (MM6), or a 2.97 (M12) low gear. In a 2500lb car making upwards of 400 ft lbs of torque, on street tires, the most gear you want to run is about 3.5. This goes double if you're not going to run flares and wider wheels/bigger tires. a 2011 Camaro weighs nearly 4000 lbs, has a 13"-wide tire, and runs the 1/4 mile in the 12s with a 3.45 gear! ***

 

Anyway, this guy was so disgusted with his car he was ready to sell it. I suggested he go to a 3.54 gear (is there anything taller available for the R200?), a taller tire, and gave him the name of a tuner who could help him try to tune out some of the bottom-end power). I told him if it was my car, I'd go with a longer duration cam, which would not only move the powerband higher in the rpm range, but would also sound a lot cooler at idle. I don't know what he ended up doing, I haven't seen him again, but lately, thinking about that 12.60-running L28ET, I've been wondering if an LS swap might be overkill for a S30 with 8-9" wide rear wheels.

Edited December 5, 2011 by seanof30306

[letitsnow]

I have an FC rx7 with a 5.3, I could see how the LS2 in a lighter car could be a handful. This thing will spin the crappy 7" wide tires nearly at will below 60, with 100hp less than an LS2, putting a set of 17x9 wheels with 255's made it a bunch more manageable.

 

After doing the LS1 swap, I see why it's popular, it's easy. You drop it in, have someone remove emissions/VATS, and have a crazy fast car that runs like brand new and gets good gas mileage. Parts are easily available and if you want more power it's easy. Low 12's-11's should be easy with a stock LS1, rx7 people do it and S30's are lighter.

 

The L28ET is getting harder to find in good shape and it does take some thought to make power with, things aren't as available.

[seanof30306]

I have an FC rx7 with a 5.3, I could see how the LS2 in a lighter car could be a handful. This thing will spin the crappy 7" wide tires nearly at will below 60, with 100hp less than an LS2, putting a set of 17x9 wheels with 255's made it a bunch more manageable.

 

After doing the LS1 swap, I see why it's popular, it's easy. You drop it in, have someone remove emissions/VATS, and have a crazy fast car that runs like brand new and gets good gas mileage. Parts are easily available and if you want more power it's easy. Low 12's-11's should be easy with a stock LS1, rx7 people do it and S30's are lighter.

 

The L28ET is getting harder to find in good shape and it does take some thought to make power with, things aren't as available.

 

Since the rotary engine was designed to make it's power at high rpms, and made relatively little torque, I'd bet you have a pretty stiff gear in there.

 

what is "FC", by the way?

[letitsnow]

2nd gen chassis code, 3rd gen is FD, and first is FB. Stock gearing is 4.11, a lot of people(rx7) swap to 3.55 8.8 ford IRS diffs.

[seanof30306]

I'm still enamored of the LS swap, by the way. Especially since I drove a 2nd Gen Camaro recently with the new TCI 4l80E-based 6-speed automatic. I've always loved manual gearboxes, but the gear spacing is so close on that TCI box, and the paddle shifter was so precise I believe I would be faster on a track with a TCI 6-speed auto than a T-56. with the right converter, it's 2.97 low gear and a rearend ratio of no more than 3.50 would probably launch better than a T-56. It is wicked expensive, though.

 

Besides, I have size 14 feet, and heel-and-toe is always a ***** for me.

[seanof30306]

2nd gen chassis code, 3rd gen is FD, and first is FB. Stock gearing is 4.11, a lot of people(rx7) swap to 3.55 8.8 ford IRS diffs.

 

I always loved the way those 2nd gen RX7s. looked.

 

I had a buddy who had a 3rd gen. It was amazing.

[seanof30306]

@letitsnow:

 

I see in your sig you have (or had) an '89 Firebird. TPI, or TBI?

[letitsnow]

89 is a v6, 90 is a carb'd 355 with trick flow heads etc. The 90 is fun, but the drag based suspension(90/10's and 50/50 shocks, boxed LCA's, poly lca bushings) makes it not all that pleasing to go around a corner with.

[Bates_]

2nd gen chassis code, 3rd gen is FD, and first is FB. Stock gearing is 4.11, a lot of people(rx7) swap to 3.55 8.8 ford IRS diffs.

 

Actually the first Gen RX-7 was the SA. It wasn't until the 1981 Generation 1, Series 2 RX-7 that the chassis code got changed to FB. Strange going from SA to FB, a lot of people don't even realize that. But I guess you can say the same for going from S30 to S130 to Z31 lol.

Edited December 5, 2011 by Bates_

[SleeperZ]

With more boost and more fuel, a stock L28ET can do 12s. Lots of people have done it. Of course there are some important details left out, like good tires, a decent engine management and a stout clutch.

[Mack]

BTW, an 83 ZXT can be quite a pig, over 3000# depending on drivers weight...

 

 

are the late model turbo ZXs really that much heavier than the older ZXs?

 

I had my 1980 2+2 on some scales and with me, some tools and a cylinder head or 2 in it, it "tipped" the scales at 2960. It is by no means a stripper, either. I has power locks, windows and A/C, but no T-tops and it was converted to manual steering properly with a manual rack and had all the lines and pump removed.

 

And a first gen 240Z with an L28ET block with an upgraded turbo and appropriate mods can be downright scary to drive.

[Bernardd]

My 83 2+2 weighs 3150 at the track. I was able to run 11.23 @ 123.9mph with the original 90k bottom end. You won't see much here for drag racing info as not many drag race a z. Most are street cars or road course cars. Do a search for a user named Jersey. I think he reached low 12's or high 11's with a stock turbo swap. There's also a thread named "List your L28ET setup" with some upgraded L28 engines.

[ktm]

And a first gen 240Z with an L28ET block with an upgraded turbo and appropriate mods can be downright scary to drive.

 

Yes, yes it can, but nothing like an LS1. Climbing the torque curve is a rush, but you usually don't reach peak torque until 4000ish rpm; you have 80% or so of peak torque in an LS1 at damn near 2000 rpm. The car is very scary during simple low speed maneuvers. Turn right, apply too much throttle (anything more than 1/3) and the rear end wants to say Hi!.

 

I had a rather nice L28ET setup pushing over 400 wheel lb-ft and 400 whp. I had a stock bottom end and head. However, the car was not very reliable at that power output simply due to (my) tuning issues. California 91 octane is detonation sensitive and I could never get the timing right for the street. On 100 octane the car was a (@#&(@*$(# blast to drive, but I wanted something a bit more.....reliable, streetable, etc.

 

I swapped over to an LS1 this past summer and LOVE it. I am running the 4L60E, 3.70 rear gearing with an LSD, and tires that are 1-in. larger than stock. It's a stock LS1 save for a ported and polished TB, JTR intake, and LS6 intake manifold. My tires at BFG G-force (340 tread wear), 245/50/16. First gear is useless, second gear is useless and the car steps sideways on the very hard 1-2 shift if I am only partially on the peddle.

 

Wider is not better. A stickier tire will solve the traction problems without going wider, but once I do that then it will reveal other weak points (half-shafts) in my drivetrain.

Edited December 6, 2011 by ktm

[seanof30306]

Yes, yes it can, but nothing like an LS1. Climbing the torque curve is a rush, but you usually don't reach peak torque until 4000ish rpm; you have 80% or so of peak torque in an LS1 at damn near 2000 rpm. The car is very scary during simple low speed maneuvers. Turn right, apply too much throttle (anything more than 1/3) and the rear end wants to say Hi!.

 

I had a rather nice L28ET setup pushing over 400 wheel lb-ft and 400 whp. I had a stock bottom end and head. However, the car was not very reliable at that power output simply due to (my) tuning issues. California 91 octane is detonation sensitive and I could never get the timing right for the street. On 100 octane the car was a (@#&(@*$(# blast to drive, but I wanted something a bit more.....reliable, streetable, etc.

 

I swapped over to an LS1 this past summer and LOVE it. I am running the 4L60E, 3.70 rear gearing with an LSD, and tires that are 1-in. larger than stock. It's a stock LS1 save for a ported and polished TB, JTR intake, and LS6 intake manifold. My tires at BFG G-force (340 tread wear), 245/50/16. First gear is useless, second gear is useless and the car steps sideways on the very hard 1-2 shift if I am only partially on the peddle.

 

Wider is not better. A stickier tire will solve the traction problems without going wider, but once I do that then it will reveal other weak points (half-shafts) in my drivetrain.

 

That speaks to every concern I have about the LS swap.

 

Going back to my Firebird; back when it was a near-stock 305 making 170 RWHP, I autocrossed the car regularly, and had a blast. With the 383, it is only marginally faster in the autocross, but is a nightmare to drive. All the fun has gone out of it.

 

On a road course, it is much faster now than with the 305, but again, nowhere near as much fun to drive. With the tire I can get under the car, I think I would have been much happier with 300-325 RWHP. The bigger problem is the 453 lbs ft torque. Even with the big cam I have in it, it has a broad, flat torque curve that just overwhelms the 295/40 17 tires. I actually stayed with the 17s, rther than going with 18s, so I'd have a more sidewall and (hopefully) better handling.

 

Not so much

 

At the drag strip, I use the old Stock Eliminator technique to launch, engaging the clutch at near idle, and carefully rolling on the throttle. I have to be careful after shifting into 2nd, too. Too much throttle too soon, and it'll break 'em loose.

 

An LS powered S30 would probably not have the torque curve I do with my 383, but it'll have a much smaller tire, too.

[SleeperZ]

My 83 2+2 weighs 3150 at the track. I was able to run 11.23 @ 123.9mph with the original 90k bottom end. You won't see much here for drag racing info as not many drag race a z. Most are street cars or road course cars. Do a search for a user named Jersey. I think he reached low 12's or high 11's with a stock turbo swap. There's also a thread named "List your L28ET setup" with some upgraded L28 engines.

That's not much heavier than my '78 S30. I weighed in at 2960, so the car weighs 2800lbs.