will a 502 fot in a Z?

[Guest kc6wfs]

Will a 502ci fit in a Z?

Just currious and wondering what it would do ie 502/540 hp 1/4 mile ET with traction.

 

Any one ever do it??

 

Thanks.

Dave

[Guest greimann]

According to Cartest 2000, a 502 hp, 567 tq motor in a Z with a 3.7 rear and T56 trans will do 0-60 in 3.34 sec. and the 1/4 mile in 11.84 @ 118.91 MPH, and top speed of 194 mph. That's assuming really, really good traction and a rear that can actually take 567 lb-ft of torque.

 

And yes, it is possible to put a big block in Z, but that is a little "over the top", don't you think?

[Guest kc6wfs]

Thanks for the reply.

 

Ya it would be a little too much,

Same gains can be made from other motors

with less weight.

 

Thanks.

Dave

[Scottie-GNZ]

It is only over the top from a standpoint of weight and fit. I assume those power ratings are at the flywheel, which is what matches the ET projections.

 

A Buick turbo (stock internals) can easily match or exceed those numbers as evidenced by what I am doing, and as Dave pointed out, be about 200-250lbs lighter OVER THE FRONT WHEELS. Putting the power aside, you end up with better balance, better handling, do not overburden your brakes, do not need some crazy spring rate and get better (EXCELLENT) mileage. There are a lot of other engines that can match it but if you are shooting for the 500lb/ft torque range, anything other than a big block will require forced induction.

 

If you really want that kind of torque in a Z, you had better be prepared to live with it. Without some kind of competition tire on the rear wheels ALL THE TIME, it can be downright dangerous on the street on dry pavement!! Watching Darius spin his tires at 60mph might look neat, but if it happens and you are not prepared for it........

 

Go for it, but heed the warning.

[V8ZRACER260Z]

I'll agree with Scottie, I have a friend up here with a blown big block in his and it sits on the bump stops. Way to much weight on the front end! Like Scottie said a buick GN engine or small block is a much better choice for a street engine. How ever if your quest is the 1/4 mile have at it! Rick

[Guest 400 ci 280z]

you may want to look at pontiac engines. they create LARGE amounts of torque. here are some dyno runs with several engine www.pontiacwarriors.com goto the engine dynos at the left. they have a 455 that makes Peak HP: 532 HP @ 6000 RPM Peak Torque: 525 lb./ft @ 5000 RPM . just to give an example of an engine that puts out a lot of power and is lighter than a chevy big block

[Guest jens]

Buick 455 and cadillac 500 is only 10-15 pounds heavier than a iron 350.

The buick can be stroked to a 528 and 550 hp with stock rods is possible.

http://www.taperformance.com/car_craft_oct__2001.htm

With stage 2 alu headds its lighter than a 350.

The cadillac with a edelbrock intake weighs the same as a 350.

http://www.geocities.com/toro89/HRBC/

[fl327]

bb zcars are straight line killers i can only imagine, the cubes man the cubes, you can make other motors work to have just as much power, but man its not a big block, cant be a big block, isnt a big block, big block.

[jap tin]

There is something about those big wide valve covers on a BBC that sends shivers down my spine . If you want a big block, go for it. These are all toys anyway. If we wanted basic transportation we would all be driving Toyota Corollas.

[Guest jens]

Yea there is something special about a bigblock. The sound cant be beat. i remember i could always hear my brother a mile away then he had his pontiac 455. A car like scotties needs a good mecanic if it gets a electrical problem. I know several that had blown turbo engines because they didnt knew that they there doing and they only ran 14psi.

[Michael]

It seems to me that the key to getting good weight distribution with a big block is chassis mods to set the engine further back – way, way back. Shameless self-promotion: see my car at http://members.home.net/pparaska1/MichaelOlsBBZ.htm. Of course, with that sort of approach, something like GN V6 would result in a combo with even more rear weight bias, even less loading on the front springs and even less need for upgrading the brakes.

 

The “can I and/or should I use a big block” question comes up over and over again... I think that the reason for using a big block is low-end torque. Not peak hp or even peak torque, or actual 1/4 mile numbers. There are crate engine small blocks out there making 500 ft-lbs at 4000 rpm. Not to mention the various turbocharged combinations – V8 and V6. But how many of them make 500 ft-lbs, 400 ft-lbs or even 300 ft-lbs right off idle, at 650 rpm, with no lag and no hesitation, on pump gas, for thousands and thousands of miles of trouble-free operation?

 

In racing, you get a chance to spool up the engine before you drop the hammer. Whether it’s a manual or an automatic transmission, the prudent driver anticipates when he will need the torque, and pre-revs accordingly. Lazy off-idle response is less important than on-design performance. But what about on the street? If you’re driving along at 25 mph, with the tranny in neutral and the engine idling, when that pesky minivan in front of you finally turns and you get the spontaneous desire to punch the throttle – that’s when you want a torrent of torque right at idle. Not at 2000 rpm, but at idle. By the time I get to 2000 rpm, I like to upshift. With that kind of driving style, the big block is the way to go.

 

The 502 weighs the same as the 454 or the other stock big blocks. Tall deck and “bowtie” blocks weigh some 40 pounds more. “Superblocks” based on the Chevy BBC architecture, but displacing up to something like 800 cubic inches (!), weigh another 100 lbs or so. So the 502 will fit anywhere where a 396 fits. The issue is what to stick behind that 502 to handle the torque and to provide appropriate gearing. For example, it’s hard to find a sufficiently strong transmission that has overdrive.

 

I was thinking about getting a ZZ502 crate engine from GM, but now my sentiment is towards building an engine with help from the local machine shop; that would be based on a 454. Now the question is, how to go about doing that without getting ripped off...

[383 240z]

I have an old issue of Popular hotrodding (may 1978) that has a BBC in a 240z. he was running a 482 with a 'glide 5.14 gears and 15x32 slicks on 15" wheels. the thing weighs in at 2480 lbs Keith

[Scottie-GNZ]

A car like scotties needs a good mecanic if it gets a electrical problem

That is an inaccurate statement. My car has no more wiring than any N/A with EFI and less sensors, doodads and wiring than an OEM turbo car. With 2 exceptions, the things that make my car what it is are mechanical (turbo, exhaust, I/C, fuel system, suspension) and the human touch in tuning. The exceptions are a chip that I can adjust and a datalogger. Ironically, one of my "buddies" thinks my setup is "crude" .

 

I know several that had blown turbo engines because they didnt knew that they there doing and they only ran 14psi.

Agreed, they did not know what they were doing. Not much different than an N/A with too much compression, cam, carb or worse, too little jetting and too much advance. Chances are a turbo engine will blow a head gasket before it burns a valve or melt a piston.

[Guest jens]

I love your gn engine because it can run so fast without sacrificing idle. How do you tune it without a rolling road. How many minutes can it run with 20 psi boost with stock pistons. all european turbo experts says 14 psi is maximum for a cast piston.

[Scottie-GNZ]

A datalogger goes a long way in helping tune the engine. By knowing what the engine did on the previous run, you have some idea of what adjustments to make for the next run.

 

I am certain what the tuners are referring to is running on pump gas and even at that, there are too many variables to cap the limit of non-forged pistons to a specific boost number. E.g., there could be as much as 75hp difference between a L28ET running 14psi with a stock turbo, Starion I/C, stock DP and exhaust vs one running 14psi with a hybrid turbo, Spearco-like quality I/C, good DP and 3" exhaust. But, probably the most critical factor in how much boost you can run is octane, or in a broader sense, quality of gasoline. I can barely push 16+psi on 93 octane with 18* timimg yet at the track I push 24psi with 24* timing. Eyes light up when folks hear I run that much boost with hyper-u-junk-tic, err, hypereutectic pistons . How? Lots of octane and keep turning up the wick as long as there is little or no detonation. It is not boost that kills engines, it is detonation!.

 

The same engine that is limited to 14psi WILL run more boost with a more efficient I/C and tuning. It will also blow up at 10psi if the owner gets cheap and puts regular gas in it. It would also blow up at 11psi with a bigger turbo if nothing is changed. It would....you get the idea.

 

I certainly will not argue with those experts, but I think non-forged pistons get a bum rap. If you can afford forged pistons, IT IS, repeat, IT IS the right way to go but there is too much focus on how a piston will hold up to detonation when the focus should be on not having any detonation at all. Avoiding detonation is how to make power in a turbo engine and the pistons contributes nada in that. It is the turbo, I/C, fuel system, exhaust and engine management and......as we all know, knowing what you are doing!

 

As for how many minutes I could run 20psi boost, I am sure you do not mean minutes . I do not have a clue and have no intention of finding out, at least not in my Z. If it takes less than 11 secs to hit 125mph and still have OD to go, I would probably sh*t my pants if I held it for another 20 secs . If I ever put it on a road course, I would still run lots of octane and the same boost but probably 18* timing instead. If I get some detonation, I turn the boost down a tad.

 

Yikes! I rambled and preached again. BAD turbo bigot, BAD turbo bigot.

[Guest jens]

I know it would fly with 20 psi but in germany they run that way. One i now ran 30 miles at 6000 rpm with 15psi in his turbo converted opel manta 2.4 competing against a volvo t5r let me tell you nothing could be reused in that engine then the pistons melted because of a ecu problem with 150 mph. How about the wiring is it easy to make a gn run in a z.

[Scottie-GNZ]

Yep, I have experienced long high speed runs in Germany. In '85 I bought a 79 911 tuner car (Max Moritz) and drove it for a week before shipping it over. On the way from a local event at Hockenheim I got into it with an Alpine A310 V6-turbo and we ran probably more than 30 miles flat-out. Never was more scared in my life behind the wheel, yet at the same time, never was more focused and with full confidence in the car. By coincidence we exited at the same time and he beckoned me over probably astututely recognizing that I was not German or even European . He was Swiss and 2 total strangers met and chatted for over an hour. That will remain etched in my memory banks forever.

 

Anyway, I digressed again . Melted pistons. Surprise!. I will venture a guess this his turbo- converted 2.4 was a N/A engine and he was probably still running the original c.r. and ECU.

 

The wiring for the GN in a Z was very simple. Electricals is not one of my strong suits so I had help from a friend, one of the top GN and Z gurus around. What makes it simple is that the Z did not have EFI and the GN harness was limited to mainly the EFI. Other than finding power for the ECU and some other minors, the GN harness is totally independent. What made it diificult at the time for me was an unfamiliarity with the GN setup and most of the time was spent eliminating about half of the GN harness that was not needed for the conversion.

 

Sorry all, this thread seems to have taken a different turn.

[BLKMGK]

Heh, we need a document someplace telling everyone just how easy it is to go with a GN motor. I hadn't realized that the EFI harness was nearly sepearate but that makes sense since I've found that that's the case for more than one car. IMO the GN drivetrain is awesome for the Z. I also think the 2JZGT drivetrain from a Supra is damned near perfect but probably harder to find. 8.5:1 cr, forged pistons, and a longblock capable of 600+RWHP. I'm in awe! Now if we could just have a member build one and document it. The 7M Supra motor swap also looks good and I'm looking forward ot hearing how that one goes too. So many choices out there! Gotta' love that nice BIG engine bay!