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Ok, just to do some quick maths here... this is the compressor map for the M45 supercharger:



Back of the napkin, for 300 HP crank you need to flow 410 CFM (697 m^3/hr) and 14+ psi of boost...could be possible, but that would be way overworking the s/c AND we're still talking CRANK. At the wheels, even assuming just 10% loss, you would need 450+ CFM (765 m^3/hr) and 17.5 PSI of boost. It’s not even on the plot! This is also assuming that your head isn't a bottleneck. So, I would also bet you're not getting 300 whp, but if you really want to shut us all up, take it to another dyno and post the print.

I understand you skepticism. I'm not suggesting that others like BOE don't know what they're doing (they do - I live near them and have had my car there several times for various things and spent some time in their shop) -- but that doesn't mean that others cant figure out things that they have not or have new ideas. Yes the ECU is not publically unlocked, but my guy has connections and sources that even most mechanics don't have and has got around that problem. Again I can not stress enough that part of the key here was all the work to the head. Bolt on a MP62 supercharger and you get 217hp. Add a smaller pully would add a tiny bit more power -- but we didn't do that as I don't feel like watching my supercharger blow and my mechanic said it was not a good idea, on this build anyway, to use a smaller one, since part of my goal is to keep the car reliable. At the end of the day what it boils down to is custom one-off work vs off-the-shelf-everyone-has-it. IF you have the right guy you will always win with the custom work done. BOE, while they are fantastic at what they do, are not in business to spend 3 months on one car -- they are a shop and need a higher volume of cars going thru their shop. Sure they *might* be willing to do all that my guy is doing -- but at $150 an hour there is no way on earth I could ever afford them do do all that my friend is doing.
 

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Plug Whisperer
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This thread is a blast from the past part 2! :)

There’s probably a 50 page thread from when we first launched the TVS1320 kits more than a decade ago hanging out blower efficiencies, airflow, etc, etc...

Couple points.

A dyno thread is fun, but hardly scientific once it goes to a forum. There are simply no controls put in place in forum land. There are so many variables from dyno to dyno, that it’s simply a fruitless exercise to take seriously. Even dynojets, which are among the most consistent from facility to facility, can wear or have dragging brakes, etc... tire pressure, ambient air temps, actual IATs (post Intercoolers), engine temp, engine bay temp, trans temp all influence the numbers on the screen a lot.

As for engine mods, we’ve been through head porting to the moon and back. There’s just not that much power there. Some, yes, but not a ton. Our heads are all CNC port patched to the gaskets which helps at the margin... It’s not to say that aggressive porting doesn’t help, but it certainly doesn’t do wonders. The valves are already as big as they can get and the stock runners are by far not a disaster. Keep in mind you have a 1.8L making 190hp NA. If that were a Chevy SB 350, it would be a 600hp motor all else equal. It’s a very efficient motor, which means the head porting is quite good stock....

On the blower front. Once you go forced induction, heat saturation level is HUGE. HUGE. HUGE. HUGE variable. A dyno plot without ECU IATs post blower is meaningless. If an exige comes in hot off the street, parks, allows the IC to soak up those toasty engine bay temps, and then goes for some pulls, the results will be lower. Conversely, dyno that same exige the next morning, and pull #3 or #4 will likely be the best pull it will do. The trans gets warm, oil gets hot, and the IC hasn’t got hot yet... the little car will do great on the screen and the customer happy compared to the prior scenario.

On the M45. It will not make 300whp on a dynojet short of having nitrous. Race gas doesn’t help much because the boost is too low, so there’s not a ton to be gained with timing. That said, the M45 is by far the most prolific combo to blow up from Lotus. There’s no post blower IAT compensation and just a touch of spotty gas will detonate and “blow the welds on the intake manifold” lol (fast and furious for those who take life too seriously:D).

On the M62, main issue I see with them is boost. The BPVs are pretty substandard and tend to bleed boost. If two exiges are identically prepared or close to it and they have varying results with similar controls for temperature in place, it’s very possibly a leaky BPV... I always recommending normalizing tire pressure, to log boost, IAT, and AFR on the dyno so you have some concept of what the changes you’re making are doing vs the conditions. SAE corrections are a tiny piece of the pie. A SC’d car needs nothing like the amount of a fuel a turbo car does. People run them too rich and leave power on the table while consuming too much gas.

As for who can tune these cars. Dimsport can be used to tune these cars, but the templates are simply wrong and simply incomplete... and not by a little bit. It’s that simple. We have the Dimsport device and it collects dust. Every customer or shop I’ve seen who claims to be able to tune the ECU uses it and the operation of the ECU is compromised in every single case after it’s touched with Dimsport. A good operator can build their own dimsport templates. We’ve done it. It takes 100s if not 1000s of hours, and a car, and a dyno and the requisite logging tools to verify the templates you built do what you thought that would. There’s a company in Germany that “dabbles” with tuning the ECUs outside of Dimsport, but that’s all they do, is dabble... We have the only editor that can actually control the tables that NEED to be able to changed for proper running of the car. I’ve posted table comparisons in other threads over the years to illustrate what I’ve just described.

In the end, I only care to keep misinformation at bay. Whether someone chooses our services or someone else isn’t really of great concern. I’m/we’re plenty busy and prefer to remain high quality and low volume rather than the inverse.

With all that said, I’m sure what I just wrote is TLDR!

Party on, Phil
 

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lower power rating is pump gas and higher is E85 tune

My turbo build
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new OEM block
1200cc fuel injector set of 4
AEM High Flow 310LPH fuel pump for use with E85 for surge tank
Oil pump gear, Titanium
Garrett Turbocharger, GTX 28/63
Cosworth 10:1 pistons
super tech values and springs
DRS Race Rocker Set, 2ZZ (Micropolished assembly w/ Melonite QPQ)
ARP hardware
ACT clutch
Fidanza flywheel
taller 6th gear
Mishimoto oil sandwich plate adapter, 185 deg F Thermostat
 

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2005 Elise LSS Saffron Yellow
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Piggybacking on Phil's TLDR (that I did read, btw), I always find it entertaining when somebody makes a claim that can't be substantiated from the evidence, particularly if it includes this symbol: $. Engineering is applied science. Science is about control of variables and replicability. The more times you have to say 'I don't know' about something, the less likely that your claim is true.

An IC engine is an air pump. A supercharger is an air pump and (in front of the engine) a compressor. These are engineered machines. There are characteristic performance maps for both (see above). If you know how many CFM at what pressure and temperature is flowing into the engine you can convert that into mass flow (Because PV=NRT), calculate exactly how many grams of fuel must be injected per intake stroke for best power, how much heat will be liberated in the combustion of that fuel, and if you have heat rejection budget numbers, how much of that will result in pressure on the piston. Do a little math to get gross crankshaft torque, subtract FHP, and, with an RPM number, you have flywheel horsepower.

That's a little of what powertrain engineers do for a living.

There are many variables in dynamometer operation that essentially nobody outside of a laboratory bothers to control. We used to motor the dyno for an hour before running an FTP75 to warm the roller bearings and coils (it was a motor dyno) up to a standard operating state so that we'd get a consistent (and known) amount of frictional loss in the dyno itself. What this means is that Bubba's dyno number from first thing in the morning in January in Michigan and Junior's dyno number from 5 PM in July in Mississippi will likely be very different even if they're the same make and model of dyno identically maintained and calibrated (they never are) and the SAE power correction was correctly calculated (it often isn't).

The only dyno number that is worth a thing is a back-to-back number on the same dyno, ideally with the same car with exactly one variable changed between runs. The further away you get from that like-to-like comparison the less your number is worth, particularly if one is a brake dyno and the other is an inertia dyno.

Honestly, quarter mile times plus a truck scale are often more useful as comparison between cars (with an auto trans car or the same driver in both).

All of that said, dyno curves are useful, even if the numbers are of limited value. I've been carefully looking at the NA car curves (because I have an NA 2ZZ car). The engine has constant (ideal) displacement per crank revolution. If you manage to push the HP peak up to a higher RPM (because you improved volumetric efficiency at high RPM), you'll be getting more power (because you raised torque output in that RPM region). So where the torque peak is, where the HP peak is, and how steep the curves fall off can tell you quite a lot if you're reading the tea leaves correctly. The numbers...not so much.
 

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Discussion Starter #25 (Edited)
Alright boys, let's stay on topic and keep the Dyno postings coming.

... What this means is that Bubba's dyno number from first thing in the morning in January in Michigan and Junior's dyno number from 5 PM in July in Mississippi will likely be very different
Yep, that's the reasoning for this whole thread: before-and-after dynos only. Sounds like we're in agreement. Also, only results apparently made on the same dyno will be considered in the main results I'm compiling.

If it bothers you that some mods take hours or days to complete and the car can't be re-dynoed before the sun sets or the air changes on the same day, then you're welcome to ignore our efforts here. This is our attempt to make the best of the data/evidence that is actually possible to gather. If somebody happens to install a part and re-dyno in under an hour to get nearly the same environmental variables, then all the better.

I appreciate the passion for vetting truth from untruth folks, but let's ignore the 300rwhp MP45 and just stay on topic and post some before-and-afters! :bow::bow: Claims made without a before-after dyno are being ignored anyhow
 

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Discussion Starter #26
My turbo build
===============
new OEM block
1200cc fuel injector set of 4
AEM High Flow 310LPH fuel pump for use with E85 for surge tank
Oil pump gear, Titanium
Garrett Turbocharger, GTX 28/63
Cosworth 10:1 pistons
super tech values and springs
DRS Race Rocker Set, 2ZZ (Micropolished assembly w/ Melonite QPQ)
ARP hardware
ACT clutch
Fidanza flywheel
taller 6th gear
Mishimoto oil sandwich plate adapter, 185 deg F Thermostat

Forgive me, I don't fully understand what was present in the "before" vs "after"

One pull is labeled Turbo62, and the other Turbo78. What was actually changed between pulls? Did you change a the boost on the turbo or something?
 

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Discussion Starter #27
When I get more than a spare few minutes at work, I'd like to reformat the list in post #1 to be a table, showing exactly what was present before and after each dyno, so that we understand exactly what was tested. Ideally, only one change is being tested at a time, but in some cases multiple changes are being tested. This means we can't say which change gave the HP gain/loss, but we do know that the combination/package created the gain/loss, which may be informative for those considering doing that same combination/package. That information is therefore worth tracking and compiling, even if it's not as valuable as we'd like it to be.
 

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Here's an old Hass turbo car that came to us with a piggyback and bunch garbage controllers from a typical "import tuner shop" before and the after is after we tuned on the stock ECU... The hardware was still a bit dodgy but cleaned up a lot. Motor was a bit tired too, but ran immensely nicer.
 

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Plug Whisperer
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Here's a stock Elise we did a decade ago or so... stock vs REV400 build with a bit lower compression and a bit more boost...
 

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Plug Whisperer
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Here's another build like the other... Some of the goodies to let the 400 breathe a bit better on a stock motor vs all stock NA.
 

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Plug Whisperer
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Here's my 1996 LX450 (Land Cruiser) daily driver with a cummins 12V 6BT engine swap we did. just for fun :)
 

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Plug Whisperer
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Here's a good running NA stock pull vs our tq200 pull. The numbers were a little happy on these pulls, but the curves represent the smoother powerband.
 

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Here's a bone stock Exige 240 with just our tune added to it. No changes other than a quick flash and and another pull after the flash...
 

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Phil is killin' it. Haha. Love it.

I come from a decade of JDM work, and have always pressed on about before and after dyno results (preferably in the same day, weather, and certainly same dyno) for the deltas, which matter most. I could care less if someone makes X on this dyno, if I know it'll be 30-40whp lower or higher somewhere else. Numbers mean nothing. Before and after is life in these comparisons.

Speaking of, I've got goals and 'recipe' work I'd like to discuss with BOE. Phil, whats the best way to get a hold of you? Rather, best time...I know you're immensely busy. Feel free to PM on this, otherwise, I'll try again tomorrow.
 

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shay2nak
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My 07 Exige S has about 265whp on a dynojet with...

RLS intercooler
2bular headers/decat/GT3 exhaust
Cup box with K&N drop in filter
525cc injectors
Stock fuel pump (160)
Stock pulley (3.2")

I'm going to reinstall the 3.1" pulley after I get this setup sorted. Not sure if I should just drop in the pulley and retune it. Don't really want more than 285-290whp on the stock motor & transmission. Still have about 50lbs I can drop off the car to get it under 1900 lbs.

Actually have some more room at the top end for more power. I think I can get to 270whp. Still trying working it out with @turbophil, even though he's a tough guy to get a hold of now! Just found a new shop closer to me to dyno, will take the car soon. Already dyno-ed my M3 there so good to go.
 

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shay2nak
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If you have any before/after dyno pairs to share, that would be excellent! We're looking for before AND after results only :) :up:
I have lots of dyno graphs. Did somewhat of a stock baseline. I'll dig them up.
 

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Done in BOE shop:

Rev 300 with stock exhaust and BOE air intake.


169 hp @ 7500 rpm; 126 tq @4350

254 hp @ 8400 rpm; 169 tq @ 7450
 

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Discussion Starter #40
The list is coming along nicely! I still haven't completed my project to fully scour the annals of this forum either. More will surely come (when I get time :p)
 
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