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Post by Debs on Aug 30, 2006 0:24:22 GMT
Next meet is Sunday 3rd September.
I doubt I will have the N2O fitted by then (4 days is a wee bit tight to fit and test), so I'll be running NA (normally aspirated) with the recent engine mods.
Hopefully I should take at least a second off my Standing Quarter time.
Wish me luck!
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Post by steve on Aug 30, 2006 8:05:58 GMT
Good luck from me Debs - I'm impressed BTW what engine mods have you done to date and estimated BHP ?
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Post by Debs on Aug 30, 2006 13:38:27 GMT
Vader/Taipan induction, (slightly) modified plenum and TB, some head porting, inlet manifold port-matched to head, modified valves (throat area), slightly revised cam timing, purpose-fabricated exhaust manifold, sports cat, Daytona backbox.
I'd guess I'm getting around 180+ bhp, although it's not been dynoed. TBH I reckon I've gone about as far as I can before binning the MEMS ECU - anymore engine work and I guess I will run into fuelling problems. So ATM I am weighing up pros and cons of differing ECU's.
The N2O will initially run a 25bhp 'wet' shot (combined N20/fuel mix), for testing purposes, through a progresive controller (rising rate 30%-100% of the shot over 1.5-2 seconds) so it will be a 'soft hit' of Nitrous which will be kinder on the engine/drive train and affect traction less (and it flattens the torque curve which is what I want for the standing-quarter).
Looking at the specs I should be able to run a 50bhp progressive shot with no problems.
Ultimately I think a max of a 75bhp progressive shot is possible, although I think this will require an all steel bottom end (certainly better pistons). This will be a project for the winter, along with an alloy flywheel, race clutch and LSD. ;D
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Post by steve on Aug 30, 2006 17:58:26 GMT
Thanks for the info Debs. I think your right about the bottom end upgrade. As I understand it, the standard K series bottom end is good for up to 190 bhp - after that your into nitrided crank, omega pistons, blue printing etc. That being the case are you saying for short bursts of nos the standard bottom end will take the extra grunt with no probs i.e melting pistons / con rods etc. as your going to pass through that 190 limit, albeit briefly ? BTW how long will it be before we see you competing in a TF bodied alcohol funny car ?
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Post by Debs on Aug 30, 2006 20:21:47 GMT
The bottom end is certainly good enough for a progressive 50 bhp shot. The major problem with the bottom end is piston strength above 7700 rpm, as well possible rod flex - these being RPM based rather than purely cylinder pressure based. The thing about N2O is that while it ups the power, it primarily ups the torque, giving essentially a flat torque spread through the RPM range. I dont envisage using more than 7000 rpm so I'm still in the safety zone. Furthermore the N20 will only be 'on' at full throttle opening, so it really is a 'momentary' shot.
Cylinder head temp with a 50 bhp shot, again, shouldn't be a problem, since I will be using higher octane fuel and retarding the ignition advance a couple of degrees. The major worry here is heat soak into the spark plug causing it to act as a glow plug and, hence, cause detonation. I intend to go at least a plug grade colder and use plugs with minimal earth electrode projection.
Above a 50 shot, though, piston crown temperature could be a player, so forged pistons will be needed.
As far as I am aware no one has used N2O on an MGF/TF before, however I am using data from a Lotus Elise which ran a 50 shot with no problem.
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Post by Debs on Sept 1, 2006 15:56:46 GMT
Well the N2O kit is in, just the final plumbing and electrical connections to be done tomorrow, followed by testing.
So, fingers crossed I will have 'Laughing Gas' for Santa Pod on Sunday ;D
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Post by andrew on Sept 2, 2006 6:55:37 GMT
What is your time for the 1/4 at the moment. Mine with a VVC. K&N plus SS exhaust was 15.65. The best standard Trophy 160 was 15.59. We as a club havn't done drag races for over two years and since then I have fitted 52mm TB and changed K&N for a Taipan.
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Post by andrew on Sept 2, 2006 13:24:44 GMT
I should have looked at all the headings and read further down where I saw your times. My tyres were Goodyears then and as you say wheel spin specials!. I run Toyo's T1 R's as road tyres and Bridgestone RE55 as track /comp day tyres, much better and if cold down to 22lb.
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Post by Debs on Sept 2, 2006 19:19:36 GMT
I'm actually looking at using Bridgestone drag slicks on 15" F wheels.
The times btw were for the car as stock, pre the mods.
The nitrous is now in, running a 25BHP progressive shot (50%-100% over a rise time of 2 seconds).
You can actually feel the Nitrous working - we did some extensive tests today. So tomorrow I shall run a couple of non Nitrous runs to see how the car performs off the gas, and then do 3 or 4 runs with the gas.
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Post by Jonathan Tully on Sept 3, 2006 23:15:18 GMT
Hi Debs,
How did you get on today? Noticeable improvement ;D? It was quite dry today - did that help as well?
Cheers Jon
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Post by Debs on Sept 4, 2006 10:28:01 GMT
Have you ever seen "Gone in Sixty Seconds"?
The bit where Nicholas Cage (drool) has a car with a button marked 'Go Baby, Go'?
;D
I had a rather interesting day!
I only managed 4 runs owing to the fact there were hoards of cars there and huge queues to get on the strip.
I did 2 runs off the gas to set a baseline. Traction was (slightly) better than last time but still not good, so I could only use 6000RPM off the line. These gave me an average time of 15.951 secs for the standing quarter. Given that I was running 15.429 secs last time out (and given the engine had been modded since then), this initially looked rather disappointing. However, while the weather was good (scattered cloud, 22 degrees), there was between 25-30 knots of wind straight down the strip. This would account for the times being poorer - I reckon I was loosing at least that 1/2 second, and probably more, because of the wind. Even a (usually quick) Lotus Elise was only managing 15.8 secs.
Anyway, on to the gas...
First run I got wheelspin in both first and second gear, and briefly hit the rev limiter in second, however it did feel faster. Result - 15.050 secs.
Second run I staged alongside the Elise, I could see all the boys from the MGDRC in the stand waving. Lights went and the Elise was away. I'd already decided I was not going for 'reaction time', but a good 'launch'. NOS armed, 6000 RPM, off we go. Car rolling, plant the throttle. I caught and passed the Elise. The ET was 14.716 secs with a terminal speed of 92.77 mph.
So, an improvement of over 1.2 seconds using a 25 shot of gas!
Translating that out, without the headwind, I should be capable of getting sub 14 seconds - we are now in V8 territory ;D
I love 'Laughing Gas'. I've just ordered a set of 50 jets.
Next on the agenda is getting some slicks for the rear.
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Post by steve on Sept 4, 2006 16:17:56 GMT
Well done - again, Debs BTW any pics of your car in action ?
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Post by johnstark on Sept 5, 2006 19:56:16 GMT
Great to hear your noz installation is working, and that at least you've had a couple of blast down the strip. I bet the elise driver was a bit shocked! John
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Post by Debs on Sept 6, 2006 2:40:10 GMT
The Elise guy was, how shall I say, totally gobsmacked! He came up to me in the pits as I was gathering my stuff to leave wanting to know how it was I slaughtered him. I just smiled enigmatically and pointed to the 'Wizards of Nos' sticker on my sills. ;D Steve, I'm still waiting for pics - there is one from the Aug 13 event (pre mods and pre gas) at: www.gallery.mgdrc.org.uk/santapod/santapod2.htmlBTW, 50 and 75 shot jets are ordered and in the post. I've bought some 15" F wheels fom a member on the board here, so I'll have slicks on the rear for the next event - should kill my traction problems.
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Post by Debs on Sept 6, 2006 17:12:27 GMT
The next meeting will be Saturday 14th October, with racing going on till 9pm.
There is also a meeting the following day so it looks like some of us will camp over and do both.
I'll be running 50 shot jets and will hopefully have the slicks on by then.
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