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Well, the stage has been set. Just came back from running my new motor on the dyno.
It came in at a corrected 620 ft-lb and 680 hp on the motor.
That was with a carb. Now it's time to see what can be done with MPFI, right? Factory ECM of course. It'll be a couple of weeks, but I'll post some more details as they become available.
EFI doesn't need big lines other than the p/u at your power level
Calc wise, -8 is fine.
I know of mech pump guys running 620-640 hp on 1/2" steel line.
A single walbro would work with the carb.
Boderline with efi, I'd go two to be safe.
I was wondering when you were going to get a real motor....
i got to see it and i still don't believe it!!!!!! craig that was truely impressive. what is scary to me is that its going in front of the 6 speed. it is going to be ruthless!!!!!!!!! good stuff. congrats!!!!
Originally posted by Craig Moates Well, the stage has been set. Just came back from running my new motor on the dyno.
It came in at a corrected 620 ft-lb and 680 hp on the motor.
That was with a carb. Now it's time to see what can be done with MPFI, right? Factory ECM of course. It'll be a couple of weeks, but I'll post some more details as they become available.
criag i would run 42lb injectors at 55-60 psi. that will make them 50ish. thats enough for around 850 hp if you dont rev the piss out of it.
also i wouldnt run the $8d on that motor. id run $58 or $60. $8d has some problems that i cant seem to get around on the higher hp cars. and ive tunned a few making over 450whp.
also buy me a plane ticket i wanna fly down and help tune this bad *** machine.its funny i'll be letting the cat out of the bag on my monster soon enough !!
kudos to the power output i cant wait to see what our package can do.
as for a pump i would get and aeromotive tank kit for a 4th gen it comes with asending unit. and -8an should be more then enough line to feed that monster
Originally posted by Craig Moates Well, the stage has been set. Just came back from running my new motor on the dyno.
It came in at a corrected 620 ft-lb and 680 hp on the motor.
That was with a carb. Now it's time to see what can be done with MPFI, right? Factory ECM of course. It'll be a couple of weeks, but I'll post some more details as they become available.
Sounds like a beastly motor. I'm guessing big cubes are in this equation. The torque number tends to reflect displacement better than horsepower.
So what is she or are you going to not tell until it's all done?
As for the fuel lines, if you're going to go with 2 pumps you might as well run larger line. I'd go with -8 and only -10 if you're thinking of more horsepower in the future.
Keep us posted, looking forward to the results.
The curves are a lot smoother with the EFI though. And it is deadly responsive. I think the TB was a little restrictive on the EFI run (MAP=92kPa). Also not dead certain about the correction factors on the carb runs (will validate).
I'm happy so far. Now that the engine is actually at my house, it's time to put it in the 87 T/A!
Last edited by Craig Moates; 02-12-2005 at 10:12 PM.
I tell you what, if you've never done dyno tuning on the engine stand with an emulator, you're missing out. It was so freaking sweet! Heck, I even MAKE these things and this is the first time I really, really got to give it a whirl.
Dialogue was something like this:
Craig: "Alright, try it now..."
DynoGuy: "Yeah, still a little fat up top..."
Craig: "OK, try again..."
DynoGuy: "That's better, picked up 20 or so. Try taking out some more, maybe add some around 5200..."
Craig: "Alright, give me a sec... OK, try it again..."
DynoGuy: "Sweet, look at that curve. It's flat! EGTs look good."
DynoGuy: "Torque is coming in a little late, let's fatten up the midrange."
Craig: "Alright. Here's 5% more."
DynoGuy: "Looks real good, EGTs and Wideband both look good. Comes in around 13.5 and works its way down to 12.5 by the time you get to 6500..."
Craig: "Sweet. Let's cool it down and add that TB spacer..."
Fun as heck. I could've done that stuff all night long. Now I've gotta unravel the PE 'fudge' and weave it into the VE tables. Should set me up for some easy part throttle tuning once it's in the car.
Cool beans.
So what are all the differences between the EFI intake and carb setup? 92kpa is a pretty heafty restriction that could definatly result in the lost HP. Also the peak torque makes sence that the carb is higher. Not that you have time but if you were AS crazy as I you'd have a thermocouple in the intake port... you might find that wet-flow has it's advantages .
Could you post a couple graphs of the dyno results between the 2? I live for the data!
Yes, the difference in terms of induction is as follows:
Carb: Dyno shop 1050 Dominator on a 4150 flange adapter 'funnel'. Not sure what the MAP was during these tests.
EFI: Using a 1000 CFM DFI-type 4-bbl throttle body.
Everything else is the same, right down to the manifold. Adding the 'aerofoil' carb spacer didn't make any difference on the EFI.
Think wet would be better? I was thinking the opposite, but heck, if you cool things down via the wet flow aspiration, I suppose it could help. I was thinking that more mass and thus frictional losses through the manifold would slow things down. But, if the manifold is far from being a restriction, then I guess you don't gain too much in that regard.
I'm thinking of changing things up by implementing a better throttle body (see attached pic, totally sick, best I can find, ultra sweet! Claims 1550 cfm.).
I'll post some solid numbers once I get all the data downloaded from their system.
Originally posted by Craig Moates
Carb: Dyno shop 1050 Dominator on a 4150 flange adapter 'funnel'. Not sure what the MAP was during these tests.
Just always sumtim, ain't it?.
What injectors did you go with?.
Did you do any fuel comsumption calcs?.
Gotta watch you data logs for what goes on during AE (actual AFR) once you get it in car. And *any* signs of pre-ignition. While the dyno is neat, it doesn't do the transitions like what you need with it in car.
Keep that up, and you'll be needing to data log the WB, real time, in scope mode (ie forget the averaging).
Yes, the transitions on the dyno were messy at best. I didn't even bother with the AE until it's in the car.
I'm all ready with integrated WB datalogging on the 730, simulated NB input as well.
Ended up going with those shorty Mototron 60#ers. It looks totally sick, ultra low profile. No, no fuel consumption #s yet, I'll check it all out once it's on the road. I do like data ya know...
With the 12.5:1 compression, I've gotta get a barrel of unleaded 105+ here at the house I suppose. Maybe a couple of them ;^).
Yes, forget the averaging. I'll be analyzing individual 'pulls' in 3rd gear, assuming I can get it to hook in 3rd... Muahaha!
Tires are a good weak link for now, just 9.5" drag radials.
So is it a pretty sure bet that the TB is restrictive? I was seeing MAP readings around 94 or so at/around 4500, and then dropped to 92 or so around 5500+. Just want to make sure before I go ahead and drop some more dough.
I had the MAP plumbed to a TB port that is offset in a little recess. I don't guess it should have experienced any venturi effects?
That TB is so freaking sweet looking though, can't hurt. Here's another angle:
Craig, what was baro with both? Not that the following could be possible BUT I was able to pull a small bit of vacuum in our dyno cell when the exhaust van and room vent were both on and the door was closed. Needless to say we had to put up with it because at 14,000 RPM even 0.6L of engine sounds mighty dangerous (and is when things go wrong).
I still think the carb is going to make more hp because it's cooling down the intake charge through the use of the intake manifold surface area. The port injection doesn't have this advantage so the plenum gets heat soaked. Even though alky injection and extra injectors have been proven to make more HP on turbo's doesn't mean they won't do the same for a n/a engine (obvious gains are much lower).
Not that you'd have the ability to install a 7th injector... BUT accel makes a TBI that uses 4 port injection injectors right below the butterfly's... hint hint. Bah, too much work not enough play time!
Curious, how much tuning on the dyno did you get? I ask because you said you got a 13.5 afr and then it richened up to redline... did you try anything richer than 13.5? If you're making peak torque with a 13.5 afr you've got some fancy pants heads on that baby with excellent quench. Reading above I noticed the high compression ratio so yeah, 13.5 seems about right.
Originally posted by Craig Moates So is it a pretty sure bet that the TB is restrictive?
I had the MAP plumbed to a TB port that is offset in a little recess. I don't guess it should have experienced any venturi effects?
That TB is so freaking sweet looking though, can't hurt. Here's another angle:
I'm not convinced. The wave action inside a manifold can be misleading.
It needs to be in the plenum. And not on top the throttle opening.
Yes, it can. An intake tract is about handing air and it's inertia. Too low or too high of column speeds, and it bends differently. Not to mention it's effects on the wave actions inside a manifold. The only for sure way to find out is by trying. The NASCAR guys are making a whole lot of power with the restrictor plate engines.....
Originally posted by Craig Moates So is it a pretty sure bet that the TB is restrictive? I was seeing MAP readings around 94 or so at/around 4500, and then dropped to 92 or so around 5500+. Just want to make sure before I go ahead and drop some more dough.
I had the MAP plumbed to a TB port that is offset in a little recess. I don't guess it should have experienced any venturi effects?
That TB is so freaking sweet looking though, can't hurt. Here's another angle:
Great numbers Craig!
I would be sure that throttle body is giving restriction, Car craft just did that 434 SBC build up - started out with 1000 cfm 4bl Tb
making 512 or so then made their way to 1350 cmf 3bl TB making 540 or so..
Not that you can trust all that CC publishes but...
Makes me feel good you made that great power with the 1000, I have had one of those brand new lying around - buut was scared to spring for the intake at this time.
Thanks for G2 working great- Had I known you had a monster like that under construction I deffinetly would have made time to visit.
Tom
__________________ 93 Firebird, 7730 ECM, most other 3rd gen running gear, 406, Ported AFRs, T56, 10.41 @ 132 N/A, 9.4 W/200 Shot 93 oct
I think where you referenced vaccum may have skewed your readings at wide open throttle.. Especially at higher RPMs..
Does the car stay consistantly at 92kpa? Or does it peter off to 92kpa? Usually when I see a car with a small throttle body it will start off at a reasonable number then fall off at higher rpm.
Did you guys get the same AFR and EGTs as the run with the carb?
ah ah ah a throttle body that is rated at 1000cfm is flowed at 28inch of water. a carberator is flowed at 1.5 inche of hg. and to be honest thats alot of difference. typically a 1050cfm carberator will outflow a 1000cfm throttle body. also the venturi shape of the carb has alot to do with the effectiveness of its flow.
Yes, I think it could have been slightly skewed. Venturi effect there could have had an effect. I might do some experiments to clarify the possibility.
It came in around 96 or so, and then dropped gradually down to 92 above 5500. So yes, it peters off.
Once I start driving this on the street, I'll do it again to check the MAP depression. Then, I'll relocate the MAP port to the manifold. If there's no change or if the MAP is still depressed, then I'll change throttle bodies for sure.
Screw it, I'm getting that throttle body. My wife even said "If it's a restriction, then get the bigger one!" Gotta love her...
The only problem with that huge TBI is going to be the low angle flow. Crack that baby open just a little bit and it'll flow a ton of air, this will screw up your AE a tad and make it a lot harder to control on the street, but you probably already knew that.
Just another note, next time (if ever) you get on a dyno, leave the carb with no fuel. The TPS could be rigged up and you'll have your actual HP difference.
Still not graphs for us to drool over
Thats a very good Idea.. I read in a article once this guy was taking carbs and gutting them. He'd bolt on a simple 0-5v tps sensor and let it fly. It was really cool.
Got it on the chassis dyno today. Ran it out and looked real good. It really wasn't performing as expected, but then we removed the Y-pipe and went open header. Looks like an exhaust upgrade is in order. Picked up 80hp there alone. Doesn't matter how much tuning you do, open exhaust is needed for big cam with big overlap.
Ended up around 13.0 on AFR across the board with about 33 degrees all the way up. Definitely no ceiling to this motor up through 6500.
Looks like about a 20-25% loss versus the engine stand. Not bad, considering the addition of 6-speed, rear end, tires, accessories (including WP, AC, etc), 1-3/4" headers.
24% seems like a lot of loss at first, but the initial engine dyno results were on carb, right? So 24% after tranny/rear-end and accessory loss, plus the transition to EFI doesn't seem so bad.
A little more tuning (AA) and some equipment tweaks and I bet you get even more of that back.
Looking back at the peak of 680hp engine versus 517hp chassis, it's looking like that 24% loss is a pretty solid and expected figure. We ran it again today and put the air cleaner back on, maybe lost 10 or so from that (14"x3" K&N drop base, solid lid), but statistically speaking, it's pretty repeatable. Wiggled timing and fuel just a little more, but no further gains. Couldn't get up the balls to spin it to 7k, I kept backing off around 6500. There's probably some more up there, the curves kept going up, but that's fine. I'll leave it up there as 'headroom'. Idles comfortably at 1050 or so now, will try and push it a little lower. Seems to like 40+ degrees down low.
I did some poking around in these and other newsgroups, as well as asking around with some of the experts, and the consensus is that 24% going from engine dyno to chassis dyno with M/T is directly in line with expectations, even at the low end of loss numbers once all accessories and variabilities are considered. So if we consider that the EFI test on the engine stand could have suffered 3-5% loss from 1000cfm TB restriction, and that it was subsequently recovered with the bigger TB, then it stands that no loss was seen going from carb to EFI. The lack of restriction presented by the 1-3/4" headers surprises me though, and makes me think that the engine dyno test could have suffered from some sort of exhaust inhomogeneities even in 1-7/8" primaries.
Now it's time to upgrade the exhaust, install a 9", and then maybe get this thing to hook.
As a refresher, this combo is as follows in terms of relevance to this message board:
441ci SBC, 12.5:1, 110-leaded,
Dart Iron Eagle 4.325 deck, BBC cam
T56, aluminum flywheel
4.125 bore, 4.125 stroke, 6.125 rods
0.685"I/0.672"E, 269I/278E@0.050, 110 LSA
Dart Pro 1 250I/178E@.400, 307I/222E@.700
1550cfm TB, single-plane homebrew MPFI
60#/hr MotoTron Shorty hi-Z, Aeromotive A1000
Factory 1227730 running modified $8D S_AUJP_V3
And yes, it's running on the Ostrich full-time ;^).
("...I'm also a client!")
I'm sorry bud, and am not trying to get kicked from the board, but you are about 200hp shy of your potential. Spend some time looking at your intake manifold and also the cam profile at every degree of motion. The exhaust port needs to flow at least 190 at .300" too. The headers need to be stepped maybe more than once and flow the heads with your primary tube size too.
Quote:
Originally posted by Craig Moates Looking back at the peak of 680hp engine versus 517hp chassis, it's looking like that 24% loss is a pretty solid and expected figure. We ran it again today and put the air cleaner back on, maybe lost 10 or so from that (14"x3" K&N drop base, solid lid), but statistically speaking, it's pretty repeatable. Wiggled timing and fuel just a little more, but no further gains. Couldn't get up the balls to spin it to 7k, I kept backing off around 6500. There's probably some more up there, the curves kept going up, but that's fine. I'll leave it up there as 'headroom'. Idles comfortably at 1050 or so now, will try and push it a little lower. Seems to like 40+ degrees down low.
I did some poking around in these and other newsgroups, as well as asking around with some of the experts, and the consensus is that 24% going from engine dyno to chassis dyno with M/T is directly in line with expectations, even at the low end of loss numbers once all accessories and variabilities are considered. So if we consider that the EFI test on the engine stand could have suffered 3-5% loss from 1000cfm TB restriction, and that it was subsequently recovered with the bigger TB, then it stands that no loss was seen going from carb to EFI. The lack of restriction presented by the 1-3/4" headers surprises me though, and makes me think that the engine dyno test could have suffered from some sort of exhaust inhomogeneities even in 1-7/8" primaries.
Now it's time to upgrade the exhaust, install a 9", and then maybe get this thing to hook.
As a refresher, this combo is as follows in terms of relevance to this message board:
441ci SBC, 12.5:1, 110-leaded,
Dart Iron Eagle 4.325 deck, BBC cam
T56, aluminum flywheel
4.125 bore, 4.125 stroke, 6.125 rods
0.685"I/0.672"E, 269I/278E@0.050, 110 LSA
Dart Pro 1 250I/178E@.400, 307I/222E@.700
1550cfm TB, single-plane homebrew MPFI
60#/hr MotoTron Shorty hi-Z, Aeromotive A1000
Factory 1227730 running modified $8D S_AUJP_V3
And yes, it's running on the Ostrich full-time ;^).
("...I'm also a client!")
Carburetors atomize the fuel better than we can with conventional injectors.(Orbital had the right idea, which is why it was bought and shelved) What we can do with efi is control the fuel curve better and change the timing after peak torque. Not bad numbers Craig, just could be better is all...sorry to nitpick.
Originally posted by InTech I'm sorry bud, and am not trying to get kicked from the board, but you are about 200hp shy of your potential.
So, to be clear, you're saying he should be laying down 717 hp at the tires? And you pulled this number from where? Based on the information on the setup he posted? Do you have a software engine simulator running in your head? Where did you pull that number from really? =)
Just kiddin', kinda, but I'd like to hear your reasoning.
No, we can't ever argue "at the tire" hp numbers, many many factors change that. As far as the software engine simulator, I think we both know that software simulation is only as smart as the author. One factor I carry is my own experience... 409 cu in SBC @ 840 hp na, so yes I do know how to make it and what is required. I am in no way trying to "dis" Craig as those numbers are something to be proud of and many would wish for those numbers. I am, however, stating, that there is something to be gained with the equipment he already has. The head numbers aren't out of line but could be improved quite a bit, which also allows camshaft tuning. Re-reading my post...I really shouldn't have replied the way I did, but since this is a DIY forum I welcome questions as to the how and why what needs to happen dynamically inside the engine.
When the ohio state site shut down a few years ago, I really haven't frequented any web places, but it is really cool to see all the neat things you all have done over the last few years. I'll try to help any way I can.
Quote:
Originally posted by Mangus So, to be clear, you're saying he should be laying down 717 hp at the tires? And you pulled this number from where? Based on the information on the setup he posted? Do you have a software engine simulator running in your head? Where did you pull that number from really? =)
Just kiddin', kinda, but I'd like to hear your reasoning.
I believe it. Numbers like that really are do-able. I guess higher revving with a significant increase in head performance would help. Something like the 32-valve jobbers would be sweet, or even some 18 degree heads. I'd thought about the option of 18 degree, just shied off. Regret it a little in hindsight, but it'd have added a good chunk of change.
I'm not so sure there's anything left in the cam design, other than maybe easier driveability down low if coupled with a heavier flywheel. Could be though. I will be looking into header design, exactly as you suggested, something like a 2" / 1-7/8" stepped design.
And hey, this goes for anyone, feel free to offer observations and comments on stuff. I for one never take something as a slam or critique, and try my best to be open-minded and learn from commentary. Wish more folks could do the same!
As a refresher, this combo is as follows in terms of relevance to this message board:
441ci SBC, 12.5:1, 110-leaded,
Dart Iron Eagle 4.325 deck, BBC cam
T56, aluminum flywheel
4.125 bore, 4.125 stroke, 6.125 rods
0.685"I/0.672"E, 269I/278E@0.050, 110 LSA
Dart Pro 1 250I/178E@.400, 307I/222E@.700
1550cfm TB, single-plane homebrew MPFI
60#/hr MotoTron Shorty hi-Z, Aeromotive A1000
Factory 1227730 running modified $8D S_AUJP_V3
And yes, it's running on the Ostrich full-time ;^).
("...I'm also a client!")
Hi Craig,
Those cyl head flow figs look like unported 230cc Dart Pro-1's, is this correct?? I would be surprised (but impressed) if they were out-of-the-box.. Also, what type of intake is that?? A converted Super Victor?
Thanks,
Ben.
__________________ Red/Red 84 Vette. 383 Crossfire 12.26 at 114mph
The head flow numbers were taken from the bench test after very mild work. Just a little bowl transitioning, 5-angle valve job, and port matching. No hogging or smoothing really.
Yes, they're Dart Pro-1 230cc castings, and then we did the valvetrain setup ourselves. 2.08" intake valves.
I've been driving it around a bit lately, it really rips some a$$. That 6-speed is a hoot, especially with the new Moser 9" True-Trac and drag radials.
I've got a horrible vibration above 60 mph that I'm trying to figure out. I think it might be a defectively bent axle. Tried everything in front of the rear yoke. Once I get it figured out, I'll come back with the new chassis numbers on the big headers and the new rearend.
I've got a horrible vibration above 60 mph that I'm trying to figure out.
What rear gears do you have? Drawing from my F*rd experience the Fox-body Mustang needs an aluminum driveshaft if you install 4.10 or numerically higher gears. The critical speed becomes 60 mph and it'll shake you out of the seat with the stock steel driveshaft (even after a balance).
Just a thought...
__________________ '96 Bronco: 302, 5-spd, 4wd, 32" tires '84 Impala: 350 with Dart heads 200cc IR 72cc CC, Ferrea valves, 9.3:1 compression zero clearanced, Comp 276HR cam, 1.52 Pro Mag roller rockers, ported Torker II + 1" spacer, DIY 4bbl TBI, 95#/hr injectors, single GT45 turbo, boxed control arms holding a GM 8.5" G80 with 4.10's
Originally posted by Craig Moates And hey, this goes for anyone, feel free to offer observations and comments on stuff. I for one never take something as a slam or critique, and try my best to be open-minded and learn from commentary. Wish more folks could do the same!
That's funny. Am I still a "good guy"?
Anyway, that sounds like a nice setup. Not sure if you have one, but sometimes a trans. blow shield will cause some vibrations if it wasn't dial indicated. May not be it, but is worth checking if you have one.
Yeah, watching an engine dyno run is something else. Once you hear the exhaust snap like it does then you know that engine can withstand just about anything.
How is the $8D working out with the high HP figures?
That's funny. Am I still a "good guy"?[/quote] Yep...
That new 16-bit 8-mbit emulator is working like a charm, too. Haven't really done much with the trace capability yet, since it's aimed right into the heart of the LS1 for its first mission and that's all fairly well defined. Hardware-wise, it's proving to be very robust, other than USB cabling issues. But with the introduction of the wireless emulation, that is all getting ready to go away.
No trans shield in place. Solid engine mounts, poly trans mount. Vibration is invariant with respect to engine speed. Changes slightly whether under load or not, but not much. Changed 3" steel balanced driveshaft for a 3.5" steel balanced shaft, and there was no change. Swapped tires and wheels, and rebalanced wheels, no change. Does it on the road and on jackstands. Doesn't transmit very hard through the shifter, but boy the rear cabin just resonates like crazy. Invariant with pinion angle, tried range from zero to 4 degrees. No endplay in the T56 output shaft. Neutral or in gear, it's still there.
No, not really targeting the import stuff. They just were kicking and screaming for toys. You know how it goes, they've gotta 'chip it up'. A local guy here (owner of Thunder Racing) has been pestering me mercilessly for like 2 years for the RT LS1, so that's been an ongoing thing. And I've got a 99 and 05 General Motors product in the driveway that beg attention as well (truck/SUV).
The EFI was by far a broader and earlier torque curve. But we didn't do too much optimization around that on the carb. Didn't even have the WB hooked up on the carb. The carb runs were really more of a shakedown / break-in while I got the manifold ready. I still need to grab the numbers from the engine stand runs, but I'm putting more stock in the chassis numbers in hand and those to come. Plus, I was pretty shy on the RPMs. It wasn't falling off on the chassis in terms of HP, and the Tq wasn't dying either. Ended up being 530rwhp corrected, but I didn't spin it up past 6500 really. I've now become fairly comfortable with a 6800 pill in the MSD box around town so we'll see.
I spent several days recently on a controlled-load dyno for marine applications playing with the LS1 stuff, and that is just sweet. Tell me what MAP and RPM you want to target and hold, and then I can go there and hold it while you tweak your fuel and spark to realize peak torque (all that really matters in the end) at those conditions. Map it all out, and take the numbers home right to the tables in realtime. Come back with some validation pulls. Pretty freaking awesome. One thing I learned more than anything is that if you get timing within 3-4 degrees and fueling within 0.3-0.5 AFR of the point of optimum diminishing returns, you're there. Just put it on the conservative side once you stop gaining as you come in aggressive. My next motor that goes on the stand will go that route, no more Kwik-Pull engine dyno numbers. Totally radical, but very labor-intensive.
Oh, by the way, in answer to the earlier question. The manifold is a Dart tall-deck 23-degree manifold. Modified for EFI of course, for the shorty Mototrons.
Originally posted by Craig Moates No, not really targeting the import stuff. They just were kicking and screaming for toys. You know how it goes, they've gotta 'chip it up'. A local guy here (owner of Thunder Racing) has been pestering me mercilessly for like 2 years for the RT LS1, so that's been an ongoing thing. And I've got a 99 and 05 General Motors product in the driveway that beg attention as well (truck/SUV).
The EFI was by far a broader and earlier torque curve. But we didn't do too much optimization around that on the carb. Didn't even have the WB hooked up on the carb. The carb runs were really more of a shakedown / break-in while I got the manifold ready. I still need to grab the numbers from the engine stand runs, but I'm putting more stock in the chassis numbers in hand and those to come. Plus, I was pretty shy on the RPMs. It wasn't falling off on the chassis in terms of HP, and the Tq wasn't dying either. Ended up being 530rwhp corrected, but I didn't spin it up past 6500 really. I've now become fairly comfortable with a 6800 pill in the MSD box around town so we'll see.
I spent several days recently on a controlled-load dyno for marine applications playing with the LS1 stuff, and that is just sweet. Tell me what MAP and RPM you want to target and hold, and then I can go there and hold it while you tweak your fuel and spark to realize peak torque (all that really matters in the end) at those conditions. Map it all out, and take the numbers home right to the tables in realtime. Come back with some validation pulls. Pretty freaking awesome. One thing I learned more than anything is that if you get timing within 3-4 degrees and fueling within 0.3-0.5 AFR of the point of optimum diminishing returns, you're there. Just put it on the conservative side once you stop gaining as you come in aggressive. My next motor that goes on the stand will go that route, no more Kwik-Pull engine dyno numbers. Totally radical, but very labor-intensive.
Oh, by the way, in answer to the earlier question. The manifold is a Dart tall-deck 23-degree manifold. Modified for EFI of course, for the shorty Mototrons.
Is the marine dyno DC electric (old), AC electric (new), water brake automated control, or eddy current? Was it a motoring dyno and if so how much hp can it hold?
I've been looking for a motoring dyno good too 600hp. The biggest I've seen personally were 300hp units . Also, could you send me their contact information.
The coolest thing about a motoring dyno was the way in which you could control the engine. I found it a lot of fun (and useful for AE testing) to hold an RPM with the dyno and snap open the throttle blades. I don't think we could have tuned alpha-n without it.
It's an automated/controlled water brake. The motor we pulled off for our testing was a 2300 hp twin-turbo setup, so yes it's plenty good for that level.
The way he has it set up is pretty darn custom, valves on the front and back of the water brake with his own interface hardware/controls. Pretty sweet indeed.
Get with me offline, and I'll give you his number. He's here in Baton Rouge. Been doing this stuff for 40 years or so.
.
Great numbers! 
