above is my old beat up M-04m alfa sprint gta , the body shell is now a wreck ,so i got a Renault alpine 310 shell ,
i wanted to have this body on a rear wheel drive chassis , at the time the M-06 wasn't released so i had to convert an M-04 to fit ,
more details on how to convert are covered really well here, http://www.rc-mini.net/joomla/index.php?option=com_content&view=article&id=66:m04-ss-conversion&catid=44:m04-ss-conversion&Itemid=82
you may notice i have no front toe in , contrary to tamiya's recommendation , this is because i run on a bumpy surface and as the front wheels hit the bumps the loaded wheel becomes dominant and the car wonders around , with zero toe the bump steer effect is reduced , i have also modified the steering links to go on top of the front uprights rather than under them to reduce the bump steer even more , i will cover this at some point soon.
the m-04m on the left has done over 100 runs on its original kit tyres , that's 20 times more runs than the M-03 or M-05 can manage.
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fast,fast,fast, 7.5t trinity duo 2 with 60A speedo , 50mph+ with the 19tooth pinion , use a 17 for shorter tracks , the m-04m in the pic above has a stock kit supplied motor and speedo with 21t ,it has the weights added and is still bags of fun ,its just not as nimble as the SS variant , the SS mod costs a only a few pounds to do and just works ,if you have a spare M-04 that you were never truly happy with then give it a go,
the speedo mount is just a spare, battery wing ,screwed to the chassis upside down with a battery retainer clip to act as a bumper or crash bar , with the extra weight added opposite the motor , moving the speedo forward like this helps with front grip , the cage opposite the speedo is from the old mechanical speedo actuator servo but is ideal for the tiny spektrum sr3100 or orange gr300 receivers ,
if you are keeping with the medium wheel base then try adding 10-15g of weight to the front bumper to get more turn in off power ,
springs and shocks, i only ever run on tarmac and hardpack dirt , so all my suggestions should be considered with this in mind ,
for the most part just adding 3racing alloy dampers and keeping the stock M-04 springs is fine ,i am using red touring car damper springs on the rear of the 'ss' and super soft red drift car springs on the front ,both from tamiya , they look the same but the red soft touring spring is quite a bit more resistive than the super soft drift car springs that came with a TT-01 drift kit! as long as you keep the fronts one or two grades softer than the rears the car will remain balanced enough to drive,
shocks have 3 hole pistons and 40wt oil f+r or as they came out of the packet.
the diff, i am still using the stock diffs filled with tamiya AW grease, the really sticky silver stuff , its a well recognised build suggestion and helps alot during braking to throttle transfers as does the rear antiroll bar,more on that further down ,
3racing do and oil filled diff , i have yet to try one but the potential enhancement of such devices can be huge but, sadly it wont fit the m-03/m-04 as the bearings are too small ,on the m-05/m-06 the bearings are larger , i dont think it would be difficult for 3racing to mod the diff to allow use on the m03/04 cars so i will email them and ask nicely if they could do a different set of outdrives for the job ,
i have tried the ball diffs on offer and have rejected them all in favour of a geared diff i dont race at any clubs , just with friends on a dusty carpark so rebuilding a ball diff every couple of runs just doesnt justify the tiny improvement, the choice is of course yours ,
the anti roll bars for the M-chassis can be a pointless thing , i have found they do have their uses, i will cover the M-05 over on that post but on the M-04 the rear anti roll bar is very useful , it helps keep both rear wheels planted by reducing rear roll, funnily enough! we have four wheels to consider here and anything you do to the rear suspension will impact on the front and vise versa, as the roll bar works to stabilise the rear so it will help keep both wheels at the front on the ground , it will also keep the front tyres square to the ground and thus more predictable steering will ensue!
from my days racing the mardave V12 i found that tweak is very important and the M-04 is no different,
once assembled and after checking that ALL suspension arms are free and have equal amounts of play /slop and the shocks are at exactly the same length left to right ,put the car on a flat surface with your chosen wheels and tyres ,what we are checking for here is that the springs are giving equal pressure to the diagonally opposite wheel, if the front right wheel is pushing the car up more than the left front, the left rear wheel will be carrying more load, thus you will have a car that turns differently left to right and pulls to one side as it accelerates and the other when you brake!
i have read that some don't bother with this, that's the guys that cant get the car on the apex consistently and clip track markers!!
lift the car by the centre of the rear of the chassis , then lower it slowly and look to see if either tyre touches down before the other , if the left tyre touches down first remove a bit of pre load to the front right and check again , if the right touches down first remove pre load the front left, it should only be out by a tiny bit! if you need more than 1mm of preload adjustment then something else is likely to askew , if your dampers are in poor shape then you will be wasting your time here so consider the whole package , all those ball joints and damper shafts ,damper oil ,steering parts all work together and if any are damaged or worn you will have trouble setting up ,
have fun .
tyres,
on the car parks that we use as a track i choose several different types of tyre , the really rough car park i use s-grip rears and 60D fronts(the M-04 kit tyres) ,on colder days i go over to M-grip fronts(in between 60d and S-grips)the S-grips have a wide temp operating window and are very hard wearing , i really wish tamiya would use the S-grip compound on a semi slick ,maybe an X pattern like the HPI X patterns , the HPI's are also a very good tyre but the rough car park eats them in two runs and they slip too much on the concrete but they are great on carpet and clean polished floors.
on the smooth concrete car park i would go for Sweep pre mount 25deg rears and 33deg fronts ,if it has been hot for a few days i go p to 40deg fronts and 33 rears , i always stay with the supplied inserts that come with the sweeps as they work very well , the sweeps are smaller than current M-chassis tyres , they are the same diameter as the older M-chassis slicks (front)and super slicks (rear)from tamiya, 55mm if remember correctly so you can gear up a bit to keep the punch or torque down a bit, these are my preferred slicks for for the rough Car park.
M-04-EL-190 (extra long)
190mm track width and 255 wheelbase M-04,
I am building this project as I want a 1/10 scale RWD rally car chassis that I can put a Ford Escort MK1 body on , I plan to gear it down and use a hot motor system 7.5T brushless in with lots of weight added to the chassis to get a realistic handling car ,
to add the length to the chassis I used two m04 chassis extenders , to get the width I used TL01 suspension arms with 39mm TT01 UJ drive shafts ,
I found that the front shock fowled the lower TL01 arms so I fitted some longer shock rod ends I had in a bits box , I also had to remove the internal travel limiters from the shocks
I will also remove the internal limiters from the rear shocks if needed but will try it as is first , at the moment the chassis has equal travel front and rear.
the m04EL has been through a few changes , a few bits of choice aluminium in crucial areas such as the servo mounts , uprights and steering hubs which are also ball raced , this helped smooth the car out in high speed direction changes , the car is so much nicer to drive and very predictable , it still need firmer tyres on the front for high speed cornering but for slower more technical driving ,on small tight tracks' the same tyres can be used front and rear to get the car to really rotate well in the turns , much like a pan car this chassis is superb when you settle into a rhythm , it rewards consistent driver input with eye opening and stimulating driveability .
for tarmac i can recommend super slicks for the rear and racing slicks for the front , on rougher tarmac the super grip radials and semi slick fronts are best , they are quits expensive though so a cheaper route is to use brca pre mount sets that can be found quite easily , just use a harder shore for the front. They usually come in sets of four so just grab 1 of each shore and have 2 full sets .
the servo is water resistant hobbyking item that cost a whopping £3.40 , its very fast and accurate for the price and has done more than 30 runs without a blip , esc is a hobbyking x-car 60A used sensored with 10.5 motor , i have all boost and turbo disabled and punch at minimum , no timing advance/retard on the motor or esc , they dont even get warm , motor and esc cost less £40 all in and utterly embarrassed my now sold ,castle creations and novak esc's . i know people love them but i say good riddance to that over priced ,malfunctioning , untrustworthy junk ! . i now own 6 x-car esc's and had zero issues with any of them , at £16 per esc ,even 6 of them cost less than my novak one which had issues from day one . they were overkill for my uses anyway .
so i rubbed the wall one too many times and the 10 year old 3racing 39mm (tt01/ta04) UJ stub axle went awry :-( ;-)
these things happen , especially when i am thrashing it to just beyond adhesion levels of the the worn out tyres for over an hour , it was a fun day !
new shafts arrived .
the day began with waking up and instantly remembering i had a new 4200mah lipo with rounded case from turnigy that was in stock at the uk warehouse! , http://www.hobbyking.co.uk/hobbyking/store/uh_viewItem.asp?idProduct=29020 ,the pack is supposed to fit the m05 which has a slightly larger battery hole in the chassis than the older m-chassis cars so thought i would give one a try .
its a tight fit and does need a shove but ,,not so tight that anything will get damaged , its as tight as a high capacity 4600 ni-mh pack ,
i swapped out the motor for the slightly milder 13.5 motor rather than the 10.5 i had in it , i also have the punch on the esc turned down to 4 which gave the old and worn tyres a slightly easier time .
so after two very long and fast runs i managed to bin it , luckily all the arms and hinge pins etc are fine , it is in need of a good clean and mechanical once over as its had a hard time with virtually zero maintenance other than cleaning the shocks and swapping wheels .
after the small issue which meant i had to stop running the m04 i went over to my holiday buggy for some grass track madness , i had to stop several times during each pack to remove the sodden grass that was wrapped in the front axles to the extent that the front wheels stopped turning completely !
this is after removing the worst of the grass build up , before running in the wet i always spray all metal pivots and non stainless fixings with a tiny squirt of gt85 then do it again after running , after todays 2 hour session on the grass the car will be getting a full strip and rebuild .
on its way is a Neo Frog (neo fighter) DT-03 which will be purely for running on wet grass , there is a huge choice of buggies from many companies that are close to the RRP of the neo frog , to be honest i really dont want a race buggy or worse something that is pretending to be one !! . i will start a new blog post for it with a short review from the perspective of a hobbyist who enjoys building , maintaining and running rc cars but may be curious enough to go racing at a local club or even the tamiya series rather than an out and out racer as thats just not where the car is targeted .
finally got the new rear tyres glued on the m04EL , went for some (BRCA)shimizu 40 slicks on hard fastrax 10 spokes , it had a hard run on a rough surface and some proper fast smooth surface to check the bond and they have stayed stuck , i did the usual clean of the tyre and rim mating surface prior to glueing .
the grip from these tyres is quite astonishing , traction during acceleration and hard braking is fantastic too , brake full on ( set to 60% on the ESC) which can lock up tamiya super slicks and the car braked quick and true .
i only did about 10 mins at the most on each surface and the tyres hardly show any wear at all .
i had the old Tamiya Raybrig NSX Honda shell on , for such a heavily detailed old body it gives the best balance of all the body sets i use on the 04EL .
The M-04ss
a short blast in a small area with the 04ss using 19t pinion , teu104bk , chrome can mabuchi 540rs , it shows just how stable it is when pushed hard , i have had a go of an m-06 , it has its motor hung out the back of the car like a Porsche 911 , they drive well but like the 911 it can be a bit tail happy .
for me and the way i drive i find the m-04 with weights added opposite the motor gives a more driveable car , i find it quite difficult to get the car to spin out , a dab of brake being needed to get the rear end to break free . as you can see it is very nimble , kind to its tyres too.
more soon :-)
