streaky Posted September 17, 2009 Share Posted September 17, 2009 Mark Adams is currently in Dubai working with Team Saluki Motorsports. I was lucky enough to book some time with him yesterday on the rolling road Dyno to undergo some mapping with my Discovery. Amoungst some very interesting finds with the injectors & plugs... we were able to conduct a few power sessions on the Dyno with my Mantec snorkel in place and also with it dissconected. The max power difference at the wheels was 4.1 hp which translates to around 8hp at the flywheel. Marks currently fitting a new type of injector to my car that was developed by Ford Motor Sport. They provide a much better spray pattern compared to the Bosche ones and dribbling injectors will be a thing of the past. He also found that the Champian Plugs reccomended by Land Rover for our climate are running far too hot...so again he's given me the best solution of NGK plug. We also used an endoscope to look down inside the cylinders to see whats happening with out having to take off the heads etc....what a great bit of kit. I'm going back on Saturday to run a second session on the dyno which will prove the before and after differences that these new injectors and plugs make. He'll also finish the mapping of the Tornado chip with a few more runs on the rollers. One very interested part of the conversation was that Marks noticed a huge difference in power loss just depending on the type of snorkel fitted. Good results came from Mantec and Safari. The worst being the Southdown snorkel which caused a power drop of upto 35hp over a standard engine! We'll also throw a K&N filter on the car on Saturday just to see how much difference it makes too. Then I'll remove it..I don't want to ruin my nice 4.6 after spending soo much money on it! What a great day...I can't wait to go back on Saturday! Quote Link to comment Share on other sites More sharing options...
Daan Posted September 17, 2009 Share Posted September 17, 2009 It all depends how carp the design of the snorkel is, good to see someone is giving some facts to back this up. I saw a lot of awfull contraptions (also offered for sale), with corrugated hose, tight bends and too small diameters. Daan Quote Link to comment Share on other sites More sharing options...
Les Henson Posted September 17, 2009 Share Posted September 17, 2009 I'm not surprised at some snorkels affecting the engine - most of them have a choke point - usually where they enter the wing. Les. Quote Link to comment Share on other sites More sharing options...
Lara Posted September 17, 2009 Share Posted September 17, 2009 I agree but would have to say that I would be looking to find a serious fault with anything that reduced power by 35bhp on a standard engine! We did some tests on Ced's TD5 90 with a very long aprox 2.5m, 2 1/2" OD snorkel that passed through his cab, this made absolutely no difference to power on his engine that was giving 185bhp. Surprised me! Also checked mine with the same result, even with a 120km/h fan blowing at the intake area. P.s. How do you equate 4.1hp on the wheels to 8 at the flywheel? Lara Quote Link to comment Share on other sites More sharing options...
Anderzander Posted September 17, 2009 Share Posted September 17, 2009 You've not said if its 8hp up or down? A well designed snorkel could increase the airbox volume or, depending on intake position, act as a ram air.. both of which could increase bhp. 4.1 f&rwhp equating to 8hp at the flywheel means you are working on a 50% loss through transmissions and running gear. Quote Link to comment Share on other sites More sharing options...
Aragorn Posted September 17, 2009 Share Posted September 17, 2009 It will depend if its a turbocharged engine or not. A turbocharged motor wont care about the longer intake run, the turbo would just spin a bit faster to make up the difference. An N/A engine however would likely show a drop in peak power due to the length of the intake piping. A true "ram air" effect only works with an extremely well designed inlet when the cars doing over 100mph, so not a concern in a landrover. I also recon the 4.1 -> 8hp conversion is waay out of whack, you'll maybe lose 20-30% thru the tyres etc, but not 50% Quote Link to comment Share on other sites More sharing options...
streaky Posted September 17, 2009 Author Share Posted September 17, 2009 How do you equate 4.1hp on the wheels to 8 at the flywheel? The actual dyno figure showed 4.1 hp at the wheels so I asked Mark what that equates to at the flywheel. My Discovery has bigger tires than standard but Mark said based on his experiance he'd give it approximatly 8hp at the flywheel. There's an exact formula but because he wasn't familiar with this particular Dyno he gave this as an approximate number. 4.1hp at the wheels is documented though and I have the printouts. Another interesting number that comes from Dyno's is the power difference made dependant on the location of the Airflow meter to the air filter. There was a Rally Prepped Range Rover in the shop too waiting dyno with a SEGEM AFM fitted. The difference in air intake pipe lengths can make a difference of upto 8% in horse power! That surprised me too. Anderzander. In my case the snorkel created a power loss when the snorkel was fitted. On a standard set up this 'Ram Air' theory doesn't hold much weight when using a OEM paper airfilter. The standard paper filter surface is sooo dense that any ram air effect created by the snorkel would be lost against it. PLus....my Mantec air intake faces backwards. If there's time on Saturday I'd like to face it forward to see what happens....but the Dyno costs are quite high and I'm not by any means a pro at this stuff! Another interesting point is that the gap between the top of the trumpets and the inner plennun chamber is very small. You'd have to reduce the trumpet height and inner plenum to get any gains from ram air on a standard set up like mine. Regards. S. Quote Link to comment Share on other sites More sharing options...
streaky Posted September 17, 2009 Author Share Posted September 17, 2009 It will depend if its a turbocharged engine or not. A turbocharged motor wont care about the longer intake run, the turbo would just spin a bit faster to make up the difference. An N/A engine however would likely show a drop in peak power due to the length of the intake piping. A true "ram air" effect only works with an extremely well designed inlet when the cars doing over 100mph, so not a concern in a landrover. I also recon the 4.1 -> 8hp conversion is waay out of whack, you'll maybe lose 20-30% thru the tyres etc, but not 50% My engine is a standard 4.6Efi...no turbo's or superchargers involved. So if what you are saying is right then my standard 4.6Efi would be putting out around 260-280 hp...and that figure I would very much doubt. The figure on this particular dyno screen gives a power figure at the wheels which inturn have to be fed through the transmission, diff etc. Like I said...I'm not a pro at this stuff so when you say that the figures are "way out of whack"...is that based on your personal experiance?. Regards. S. Quote Link to comment Share on other sites More sharing options...
bathtub Posted September 17, 2009 Share Posted September 17, 2009 Ive had more problems with leaves blocking the Snorkel during an event Quote Link to comment Share on other sites More sharing options...
Lara Posted September 17, 2009 Share Posted September 17, 2009 Hi Streaky, What you are doing is great and NOTHING is better than hands on back to back testing! so don't let us put you off! What people say is sometimes and often either misunderstood or complete carp (including me I am sure) so try to temper everything you are told with the question "does that theory hold water" a 50% power loss on a powerful engine does not in my opinion unless you have trans problems but as you say, Wheels power "is what it is" so use that as your main concern for the moment. Keep it up! Your ram pipes. I did considerable tests on our Superflow Flow Bench and found that you can bring the "roof" down to as close as 15mm to a 48mm id trumpet while pulling circ 350cfm without affecting air flow in any way what so ever. However! as soon as you get close to the side of the trumpet, 15mm and closer, airflow drops like a stone. This we found on all sorts and shapes of trumpet. We also found that a very large radius is a lot more efficient than a small "steel weber DCOE type" Lara Quote Link to comment Share on other sites More sharing options...
Lara Posted September 17, 2009 Share Posted September 17, 2009 Pete. I filled my air-filter with muddy goop after inhaling it in through my snorkel wondered why it would only drive at 1500revs and no boost I blame the ITG Filter Lara Quote Link to comment Share on other sites More sharing options...
BogMonster Posted September 17, 2009 Share Posted September 17, 2009 Ive had more problems with leaves blocking the Snorkel during an event That's what happens when you climb trees Quote Link to comment Share on other sites More sharing options...
Les Henson Posted September 17, 2009 Share Posted September 17, 2009 Or try to drive upside down Les. Quote Link to comment Share on other sites More sharing options...
Lara Posted September 17, 2009 Share Posted September 17, 2009 That's what happens when you "Drive Through" trees (Bit like an Elephant) Fixed Lara Quote Link to comment Share on other sites More sharing options...
HPLP Posted September 17, 2009 Share Posted September 17, 2009 I know some of you are wondering about the 50% power loss through the transmittion but assuming the disco is automatic, would that not hold some water as I always thought that there was significantly more power loss through the fluid over manual/direct gears? H Quote Link to comment Share on other sites More sharing options...
Steve Hiatt Posted September 17, 2009 Share Posted September 17, 2009 I've always struggled with transmissions using a % of engine power, the Yanks tend to quote a hp figure for gearbox losses, @35hp for a TH350. Pretty small potatoes I'd say. Quote Link to comment Share on other sites More sharing options...
Lara Posted September 17, 2009 Share Posted September 17, 2009 Hi Steve, You are right, it is most certainly not a percentage, You get a fairly steady power loss figure from say certain gearbox or axle etc but this power loss does go up as you put more power through it for obvious reasons, but generally not a great deal. Tyre types and pressures make a hell of a difference and so does vehicle weight and even strapping it down or not! Modern autos don't sap that much power nowadays although it is usually more than a similarly good manual. Lara Quote Link to comment Share on other sites More sharing options...
Aragorn Posted September 17, 2009 Share Posted September 17, 2009 Theres two parts to this. A big portion of the "transmission losses" is infact the friction of the tyres on the road surface. As you say thats relatively constant regardless of the power. Then you have the power lost in friction etc in the diffs/gears etc. If you consider the energy involved if you were dumping all that energy into the transmission/diffs etc, you'd never be able to keep them cool! Quote Link to comment Share on other sites More sharing options...
bathtub Posted September 18, 2009 Share Posted September 18, 2009 Or try to drive upside down Les. rrrhh ive sorted that problem with the new buggy The spare 44 is going on the roof Quote Link to comment Share on other sites More sharing options...
lansalot Posted September 18, 2009 Share Posted September 18, 2009 "There's an exact formula but because he wasn't familiar with this particular Dyno he gave this as an approximate number." There's no formula you can use to calculate at-the-flywheel from at-the-wheels. Each vehicle is different, there are way too many variables. Chances are two (to all intents and purposes) similar vehicles will be a little different (wear-and-tear, fluids, tyre pressures as said etc). If you want the at-the-flywheel figure, the only reliable way it to yank the engine and bolt it straight up to a dyno. But you're better off measuring at the wheels anyway - that's what is of actual use to the driver. Never seen the purpose of quoting "at-the-flywheel", unless it's to use as an indication of "check how much our great drivetrain is sapping!!" Out of interest (and I might have missed it in the above), what power difference (%) is that for your vehicle? Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted September 18, 2009 Share Posted September 18, 2009 "There's an exact formula but because he wasn't familiar with this particular Dyno he gave this as an approximate number." There's no formula you can use to calculate at-the-flywheel from at-the-wheels. Each vehicle is different, there are way too many variables. Chances are two (to all intents and purposes) similar vehicles will be a little different (wear-and-tear, fluids, tyre pressures as said etc). If you want the at-the-flywheel figure, the only reliable way it to yank the engine and bolt it straight up to a dyno. Well, sort of right and sort of wrong ..................... You do a run down test and the dyno determines the losses that it needs to apply to the final figure to then get the flywheel power ...........Lara will explain the exact detail as he has his own dyno................. However the sort of numbers quoted are not out of line for 4 whell drive vehicles............ BTW: Yes, tyres make a large difference, but you also have to consider what oils are in the various transmission elements, making sure the barkes are compoletely free, and even checking on the 'tightness' of wheel bearing etc............. Certainly my losses dropped significasntly just by changing the LT77 oil to SMX and the transfer / axle oils to a EP fully synthetic multigrade. Quote Link to comment Share on other sites More sharing options...
Daan Posted September 19, 2009 Share Posted September 19, 2009 Certainly my losses dropped significasntly just by changing the LT77 oil to SMX and the transfer / axle oils to a EP fully synthetic multigrade. Would you care to share with us how significant? Quote Link to comment Share on other sites More sharing options...
landroversforever Posted September 19, 2009 Share Posted September 19, 2009 I was wondering about having two snorkels (not just because i'm a tart )... i assume this would help easy the situation? Quote Link to comment Share on other sites More sharing options...
Lara Posted September 19, 2009 Share Posted September 19, 2009 I was wondering about having two snorkels (not just because i'm a tart )... i assume this would help easy the situation? don't bother unless you have 400 REAL bhp or more one good one will work fine! Unless you really are a tart Lara Quote Link to comment Share on other sites More sharing options...
landroversforever Posted September 19, 2009 Share Posted September 19, 2009 well maybe i am... but if it really does make 8hp difference... thats alot on a standard engine Especially as I like the southdown one... which apparently is a 'bad' one Quote Link to comment Share on other sites More sharing options...
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