[71 chevy]

the 509 was in a chevelle iirc.

there definitely are slow ls1s but remember that a stock ls1 camaro on factory tires was good for 13.7 secs and weight was around 3300lbs, again iirc. that should put things in perspective for you.

ill stop bashing the bbcs. I'll just talk up what I believe in, which is the future - the lsx

[67EC]

Originally Posted by 71 chevy

the 509 was in a chevelle iirc.

there definitely are slow ls1s but remember that a stock ls1 camaro on factory tires was good for 13.7 secs and weight was around 3300lbs, again iirc. that should put things in perspective for you.

ill stop bashing the bbcs. I'll just talk up what I believe in, which is the future - the lsx

I know what the LS motors are all about Ive driven a cts-v with the LS6 alot, that thing is heavy as hell but still traps 106mph. Ridiculous is an understatement. Hell my stock diesel truck runs 14.7 and with just a programmer runs 13.5@105. A 6000# diesel truck running 105mph with just a $600 programmer...did it at Island multiple times....and gets 22mpg....but I dont bash Viper trucks even though they cost over twice as much and get 12mpg, they are still cool, too each their own.

[71 chevy]

I'll stop the bbc "bashing" . at least you know what the new technology is capable of.

what are you doing with the lq4. NA or FI? carbd or efi? power goal?

[ratss454]

this thread reminded me of the crate motor shoot out that hot rod magazine did last year. with the zz572/720r engine, race weight of 3560, 4.11 gears, tci# 2251803 converter, and leaving at 4500rpm off the brake, the best pass was 10.217 @ 128.98mph. their first pass was 10.79 @ 125mph. those are not far off the pile drivers numbers with more cubes and compression.
i want to see more on the pile driver chevelle!

[Tony Mamo @ AFR]

There is no question the trap speeds dont line up with the power claimed in this particular combination (as most have already touched on.....I was @ SEMA working the AFR booth so Im a little late to the party....LOL).

While I don't know the D/A of the actual run, a 3700 pound vehicle in "OK" air (approximately 1000 foot positive D/A) only requires 655 HP or so at the flywheel based on a very proven method I have of converting typical numbers.

I think some of the problem could be how that combo was tested at Westech and what parts might have made it to the vehicle....maybe the headers were vastly different or the tune-up in that particular air was off. Also, a much greater depth of test results would really be required to better judge the potential that combo had. Seemed they barely got a clean run off when the mag deadline hit and the results were what they were.

Regarding the Westech dyno I get kinda tired of the guys that have never been there bagging on the results and the facility. Its one of the best testing facility's on the west coast....period.

And the numbers of any motor I have tested there have always seemed to pan out come track day. My last two personal combinations have both ran the number I was hoping and anticipating in my 3450 lb. C5 (with driver).

The first a 346 stock displacement build with AFR 205's that trapped 124 MPH at 1500 feet D/A produced exactly 550 HP on Westech's dyno (475 TQ).

The second, a more aggressive 383 with a solid roller (still 91 pump gas and very street friendly) went 129.5 MPH in the exact same air quality a year or so later. That engine produced 610 HP on Westech's dyno with a 1.75 header but I ultimately swapped to a larger 1.875 inch primary which showed me eight more peak on the chassis dyno. So figure 618 or so back on Westech's equipment. Based on my methods of calculating power versus raceweight, there doesnt seem to be any issues with either scenario.

I also built a mild 403 LS stroker for a GTO owner that made 595/555 on Westechs equipment and that engine pushed my customer's 4000 lb family sedan to low 11's @ 123.5 MPH.....also about right for the corrected STD power I witnessed on Westech's 902 dyno.

There are a host of obstacles to address before you go out and run a big number....all three examples I mention above were thoroughly tuned and optimized on a chassis dyno long before hitting the strip (which also backed up the flywheel numbers with a very reasonable loss shown to the rear wheels), so getting a more optimized number on a first track outting of sorts would have been a much easier task to accomplish.

Would like to see this combo on a chassis dyno and all sorted out before any more conclusions are drawn from its one or two runs down the 1320.....now that would make a much better story I would think. Hell....did they even shift this combo where it needed to be?.....there are just sooo many variables at play when discussing track results.

-Tony

[71 chevy]

Its unfathomable that a dyno operator would have different numbers for real cars vs magazine cars so based on what tony said, those mag cars must just have some horrible chassis prep.

then again, the johnny hunkins 626 hp chevelle only put something like 419 to the wheels at a chassis dyno so it makes one question...

but, I still say its unfathomable that a dyno operator would doctor numbers for a mag article

[Bob West]

I'll go LS when they build an LSXXL

[540Hotrod]

Or XXXXL!!!

[71 chevy]

Originally Posted by Bob West

I'll go LS when they build an LSXXL

how fast are you trying to go? 7.00 at 206mph?

cos ls94%x(325cid) is good for a nine second e.t on a stock engine with a cam change

http://www.ls1tech.com/forums/forced...-sec-pass.html

[Tony Mamo @ AFR]

Originally Posted by 71 chevy

Its unfathomable that a dyno operator would have different numbers for real cars vs magazine cars so based on what tony said, those mag cars must just have some horrible chassis prep.

then again, the johnny hunkins 626 hp chevelle only put something like 419 to the wheels at a chassis dyno so it makes one question...

but, I still say its unfathomable that a dyno operator would doctor numbers for a mag article

I agree, Hunkins car certainly should be making more at the tire....how optimized that whole package is though is another mystery entirely. Plus being a hero on the chassis dyno is ALOT more difficult than being a hero on the flywheel dyno. A entire new long list of parameters (and systems to be optimized) just started effecting and eating away at your bottom line.....especially when discussing auto's with performance stall converters.

One of the big problems IMO is most of this magazine testing is rushed....beyond belief I might add. I'm not sure if most of the editors like to wait until the last minute (and thats what they require for "motivation"), or they are simply understaffed but its a running joke in AFR about how most of these tests actually go down and how we usually have to produce a set of heads for a certain test in a matter of days when we could have been notified weeks or months ago in some cases. There are/were a few tests that seemed to have been better laid out with the proper time to get decent results (the BBC shoot out Henry D pulled off was one of them), but most of this stuff is last minute and without fail problems/issues are reflected in the bottom line IMO. Hell....how many stories end without a number (or a good number) due to something always popping up?

I will also say that in all my years dyno testing AFR product with numerous editors (and usually at Westech), never have we posted or printed numbers that weren't legit. But thankfully with our product the numbers usually aren't problem, but I would like to think (or hope) that even if they were, the mag guys I have worked with and the guys at Westech wouldn't go down that road (inflating them and presenting readers with false information). I really feel other issues are at play when the performance of some of these vehicles don't fall in line with the numbers produced on the dyno.

-Tony

[540Hotrod]

Tony, first...it was great seeing you again at SEMA. Hope to meet again at PRI.

As you can see from the magazine I gave you (I'll be getting you the others soon!) I absolutely agree with you about the time involved and the preparation needed to have a good dyno session. There were tons of hours involved in setting up to test different cams, intakes carbs etc. Primarily it meant making sure that everything else was perfect so there wouldn't be any drama. To do a bunch of head swaps efficiently would definitely require some time to work out the kinks ahead of time. I think rushing things often leads to less than stellar results.

Even with the head/cam swap you did with Wes on that '61 Vette deal was a long way from perfect at the track. No doubt it made lots more power...but trans issues etc kept it from performing correctly. He finally hit some low 12's next time out that were a lot more representative...but surely can do more with some work.

I've heard some first hand stories of *one upmanship* in the magazine world.....I mean just how many ways can you build a 500HP smallblock? No one wants to say they made 493HP if someone else is going to publish 506HP! That's where you get into *dyno racing* and it's actually been refreshing in some recent articles where they mention that is exactly what they are doing...printing a big number on the dyno...a legit number...but definitely NOT the best combo.

I have been very impressed that not once in my fledgling writing career has anyone in the magazine or vendor world told me what I should write. Not even hinted at it..so that's been awful refreshing.

Westech's dyno stuff has been a long running deal....but they seem to be in line these days from some of the old stuff that was printed. I've never tested there, but have talked to many who have and everyone of them considers it a first rate facility to test at as far as the repeatability of the numbers. Back to back testing seems to provide excellent results.

We've got a project coming up soon where we are going to take a pump gas 427" BBC that chassis dyno'd at 478RWHP, yet has barely been in the 12's with rotten MPH due to fuel starvation and traction/gearing issues that made the car a stone. The whole deal is going to surround leaving the motor alone...and working out getting the car to actually perform. Should be a lot of fun!

Again, I'm glad they tested it...I just hope they don't consider it *old news* and abandon it. Go back again and see what it can do with some work!

JIM

[COPO 572]

Originally Posted by ratss454

this thread reminded me of the crate motor shoot out that hot rod magazine did last year. with the zz572/720r engine, race weight of 3560, 4.11 gears, tci# 2251803 converter, and leaving at 4500rpm off the brake, the best pass was 10.217 @ 128.98mph. their first pass was 10.79 @ 125mph. those are not far off the pile drivers numbers with more cubes and compression.
i want to see more on the pile driver chevelle!

I'm not sure what was wrong that day, but their 572 numbers are absolutely horrid. My very first trip to the drags in a brand new, never run 3600 lb street car ('79 Malibu), resulted in a 10.11 @ 135 mph. A little chassis tuning and some good air has it running 9.80's @ 137 mph. This is with a PG, 3.90's, and leaving nearly off idle on the foot brake. I've yet to play with shift points, timing, jetting, etc.

I'm not saying this to brag about my results, but they really didn't do that motor justice. If I were GM I'd be upset those numbers went to print. The only valid excuse would be terrible weather and the wrong converter.