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Post by dickie on Apr 14, 2021 20:20:44 GMT
Hi Folks, I have just dropped the ITB Mongrel at Engine Tuner Plymouth. Its having a little drive on the rolling road for a couple of days of mapping. I should get it back on Saturday morning and hopefully it will be fit for my first Hillclimb over the May Bank holiday weekend. I have been running on autotune to get it driveable. I wound it up to 6000rpm on the way to work and it was pulling well. I fitted a brand new set of plugs for the rolling road mapping session.
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Rasc
Chats A Bit
Nutz troll apparently
Posts: 130 
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Post by Rasc on Apr 15, 2021 5:24:12 GMT
Good luck with the hill limb and please post the results of the mapping session. Interesting to the before and after states.
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Post by dickie on Apr 15, 2021 20:24:35 GMT
Hi Rasc,
The car was originaly at 169 bhp this time last year, I have made a few changes by removing my home made idle air control system and balance manifold, I have also gone from the Mk2.5 purple injectors to 550cc EV14s and raised the rev limit to 7600 rpm, the car also has a newer ME221 gen 2 fitted which I had running on a modified VVT ITB base map.
The main reson for upgrading the injectors was to get a better spray pattern with better control at the low end and the ability to pump plenty of fuel when I stamp on the not so loud pedal.
Its a not so loud pedal because I have fitted a remote filter and intake plenum which means I do not sound like a Hooligan at 6 am when I head to work.
I have not been able to scan the original rolling road printout to post it as its too faint.
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Post by howardb66 on Apr 16, 2021 10:53:19 GMT
That’s pretty strong already for a normally aspirated engine. A good friend of mine has a Mk1 1600 that has Jenvey ITBs, Blink head, Cams & ME221 was on the rollers last weekend at Northampton Motorsport 146 hp & 105 lbft. He was pretty gutted TBH. Especially as it was 135hp without the ITBs.
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Post by atlex on Apr 16, 2021 13:47:04 GMT
That’s pretty strong already for a normally aspirated engine. A good friend of mine has a Mk1 1600 that has Jenvey ITBs, Blink head, Cams & ME221 was on the rollers last weekend at Northampton Motorsport 146 hp & 105 lbft. He was pretty gutted TBH. Especially as it was 135hp without the ITBs. At the wheels with more or less standard compression ? that's quite good for a 1.6  At the engine power ? not much different from my white car... RSA itbs, more or less standard head, pistons, RSA mildly reground cams. |
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Post by dickie on Apr 17, 2021 18:00:11 GMT
Hi Folks, The results are in. I am down on power from last year the tuner thinks its down to the airbox and remote filter. The torque curve is very flat with the airbox and the car is quiet to drive its smooth and progressive through the rev range. Its a quick job to replace the foam filter for the extra noise and hopefully power. ( I will be using the Pipercross foam filter for competition ) 
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Post by Zed. on Apr 17, 2021 20:07:29 GMT
didn't the tuner run the car with open trumpets for a power comparison?
Rich.
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Post by dickie on Apr 17, 2021 20:32:28 GMT
Hi Rich,
I think he had a go but did not know how to get the plenum off. ( the plenum was half off when I had a look when I got the car home )
you have to take the complete assembly off the throttle body stubs by undoing the four grub screws that hold in on then you only have 10mm to get it off the stubs then it has to be rotated and pulled forward under the strut brace and the IAT sensor then has to be unplugged from the backplate, you can then undo the Dzus fasteners and take the plenum off the backplate complete with trumpets, it can then have the IAT sensor plugged back in and the backplate complete with trumpets can be re fitted, the correct allen key is in the centre consol, Simples !!!!
The other possibility for part of the power drop is different tyres running at a lower pressure.
The airbox does make make the car very civilised to drive though.
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Post by atlex on Apr 17, 2021 22:16:15 GMT
What this thread has convinced me about is that I should keep with the sausage filter and never bother going the plenum route. I've got the ducting all sorted, don't need anything more. With 15mm spacing from the trumpets to my sausage filter, back to back, Nick (Skuzzle!) saw more torque and the same power with the sausage filter on, he thinks due to some improved harmonics.. vs bare trumpets. Not a civilized car though  but I'm far from civilized so there you go. |
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Post by Zed. on Apr 17, 2021 23:23:02 GMT
With 15mm spacing from the trumpets to my sausage filter, back to back, Nick (Skuzzle!) saw more torque and the same power with the sausage filter on, he thinks due to some improved harmonics.. vs bare trumpets.  using the above guide of 350mm for 9,000rpm, that hints to ~230mm for 6,000rpm, 270mm for 7,000rpm and 310mm for 8,000rpm  obviously, being ever hopefull (& also from reading / discussions) I've made different length adapters to play with inlet length (butterfly & overall)...  Rich. |
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Post by dadbif on Apr 18, 2021 8:10:27 GMT
A plenum such as you are using is bound to reduce power, it is restricting the airflow by reducing the size of the intake, the very thing TB’s are supposed to increase.
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Post by Zed. on Apr 18, 2021 9:18:30 GMT
A plenum such as you are using is bound to reduce power, it is restricting the airflow by reducing the size of the intake, the very thing TB’s are supposed to increase. on paper it should help as the engine draws air from a remote area (filter) position, maybe the link-pipe is collecting heat from the radiator? whats the iat reading dickie? also, whats it drive like as less can be more  Rich. |
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Post by dickie on Apr 18, 2021 11:23:57 GMT
As I explained The airbox is to keep the car nice and quiet and civilised. it still goes well with it.On the road I hardly ever use full throttle apart from the odd traffic light race to 40mph. its amazing how far away you get without breaking the speed limit with a good launch.
It takes less than 5 mins to swap the sausage filter back in for competition driving.
I will try with and without plenum at my hillclimb event as I am doing both days.
The crossover pipe does get warm from the radiator. The manifold wrap is working very well and is keeping the heat down.
There is a second hand bonnet locally which I will try and buy so that I can butcher it for cool air and venting heat away.
If I stand the car at idle and have the headlamps on main beam and the cockpit fan on full I can get the IAT air temp up to around 50c This would only happen in a traffic jam though. I have not recorded the IAT under normal driving conditions though.
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Post by Zed. on Apr 18, 2021 11:55:32 GMT
If I stand the car at idle and have the headlamps on main beam and the cockpit fan on full I can get the IAT air temp up to around 50c This would only happen in a traffic jam though. I have not recorded the IAT under normal driving conditions though. exellent information Rich. |
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Post by dickie on Apr 18, 2021 19:42:08 GMT
I have found an area of the Map thats not good, At low revs light throttle it behaves like a Kangeroo as the mixture fluctuates,
It did not do that before it was tuned. Its an area that I can adjust though. The good news is I tried a launch on a quiet ( well it was till I got there ) bit of road on a slight uphill. 6000rpm then feed in the clutch with meaning, slam into second, then third, on lift off there was a satisfactory burble. clean pickup all the way. ( This was with the foam filter fitted on full noise ) |
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but I'm far from civilized so there you go.
le sigh