701 replies to this topic

[iank]

hmm i see, just out of interest why is the return line needed?

You need a return as the injectors need a very high and constant fuel pressure, this is easiest to arrange as in the following diagram.

Carbs use low pressure and the pump is low pressure and just fills up the carb reservoir until it's blocked off by the float.

thanks for the advice! what would you reccommend then?

MPI fuel tank and pump come fitted with a return port if you want to use your boot as before, so that's the easy option. Could get a shiny aluminium tank fabricated if you want to, as most of the racers use, but you'll lose your boot as storage.

[paul6266]

i couldnt help but notice that you only get 55bhp from a 1000cc micra engine plus cost of bits you need is it not cheaper to buy a vtec kit? although this is differant

[Artstu]

i couldnt help but notice that you only get 55bhp from a 1000cc micra engine plus cost of bits you need is it not cheaper to buy a vtec kit? although this is differant

Not everyone wants power, plus I have a feeling 55hp from the 5-speed Micra will feel a darn sight nicer than say 65hp from an A-series. I myself would go for the 1.3 which should give a nice solid 85hp with decent induction and extraction.

And both these engines would still be 998cc and 1275cc on the log book.

[iank]

i couldnt help but notice that you only get 55bhp from a 1000cc micra engine plus cost of bits you need is it not cheaper to buy a vtec kit? although this is differant

55bhp is for the 1.0 Micra as standard and is badly strangled by the induction/exhaust. But use the 1.3, put a decent exhaust system on rather than the pea shooter and improve the breathing and it's comparable with the Suzuki 1.3 for bhp (i.e. around 100bhp).
See here for more details on a cheap recipe
http://www.micra.com...1500powerup.php

Find a turbo Micra engine and it will fly.

Micras are pretty successful rally cars in their class so there are lots of cheap bits available to make them go fast.

Maybe I'm missunderstanding, but I'm not sure how a vtec could ever be cheaper than the nissan due to the body mods that always seem to be required. Buying a pre-made subframe rather than making your own also costs a silly amount of money (for some reason they are sold at a twice the price of a complete lotus 7 style kit car chassis).

But IMO the micra conversion has some advantages over the alternatives:
Easy to source for little cash
Easier to DIY than the other swaps
Micra engine is a little lighter than the A series (all aluminium) so suits the car better IMO than the big heavy high power conversions.
Cheapest way to get a 100bhp engine and 5 speed gearbox in a mini, certainly a lot cheaper than getting an A series reliable at that kind of power.

But each to their own, they will never have the power of a VTEC or a 2.0 Redtop, so do whatever makes you happy

[drummerian]

ok, sounds like the mpi tank is the way to go then, i take it there isn't an electric fuel pump or anything that could be used with the std carb'd tank?

i am going to the scrap yard tommorow, will be looking for smaller gearboxes than the 1.3 one i have. Any suggestions for what to look for (want to obviously make sure that i get the right gearbox), what sort of measurements am i looking for? thanks!

[jimbob69]

From what i have done so far i dont see the larger box as being a problem. Yes the frame needs a fair bit more chopping and you may have to be a bit more creative with some box section or plate but nose to tail it clears the front panel, bulkhead and the rack so therefore justifies its better ratios and strength. Plus its pretty much what you get in the uk. Im very confident it will be ok HOWEVER i must say untill mines in, plumbed and driving dont hold me to that!

[drummerian]

From what i have done so far i dont see the larger box as being a problem. Yes the frame needs a fair bit more chopping and you may have to be a bit more creative with some box section or plate but nose to tail it clears the front panel, bulkhead and the rack so therefore justifies its better ratios and strength. Plus its pretty much what you get in the uk. Im very confident it will be ok HOWEVER i must say untill mines in, plumbed and driving dont hold me to that!

thanks mate! i think i am only sceptical because after seeing flying bananas conversion in the flesh i've seen how much he has had to cut back! this however, may be due to the lateness of his engine (i believe it is from an 03 or somthing)...shall have a look in the scrappy tommorow for the smaller box, but if it can be avoided great! when do you think yours is going into the car?

any chance you can tell me where you acquires your box section? any updated pictures?

thanks

[jimbob69]

I thought you only had to cut for the inlet manifold? The boxes are the same right? mines a 94 vintage. Im poss gonna cast a custom manifold as i have access to a foundry at work or either fab one or go ott and billet machine one for car porn effect! I wont be fitting mine for a while as i need the mini in one piece untill my mk1 golf 20v turbo is finished, one at a time and all that......

[drummerian]

I thought you only had to cut for the inlet manifold? The boxes are the same right? mines a 94 vintage. Im poss gonna cast a custom manifold as i have access to a foundry at work or either fab one or go ott and billet machine one for car porn effect! I wont be fitting mine for a while as i need the mini in one piece untill my mk1 golf 20v turbo is finished, one at a time and all that......

ok thanks! flying banana has had to cut ALOT of the subframe apart, and the engine does come very very close to the steering rack!

am still looking into the option of the smaller box...does anyone have ideas on measurements?!

[jimbob69]

Mine is about 20mm clear of the rack and with the rock solid landrover mounts and a light engine should be fine, its about 10mm clear of the front of the subframe so its close but im not worried to be honest. Thats why it took me so long to do really, spent ages 'choppin a little and try again' before i decided to hack and use box section! Im not saying you cant follow bigchiefs approach, in fact i would like to see him do one with the larger box as im pretty sure he would work his magic and make it look so easy!

[drummerian]

Mine is about 20mm clear of the rack and with the rock solid landrover mounts and a light engine should be fine, its about 10mm clear of the front of the subframe so its close but im not worried to be honest. Thats why it took me so long to do really, spent ages 'choppin a little and try again' before i decided to hack and use box section! Im not saying you cant follow bigchiefs approach, in fact i would like to see him do one with the larger box as im pretty sure he would work his magic and make it look so easy!

haha cheers for the advice mate, whats your plan regarding fueling?

do you have a flip front? or are you attempting this into a std mini?!

[jimbob69]

Standard front and i dont want to cut anything. Mpi tank and pump seems the easiest way IMO

[Ethel]

There are roller vane pumps you can mount remotely - see the Metro Turbo. The return can just be Tee'd into the pipe between the tank & pump. I'd still go for an injection Mini tank if you can.

[drummerian]

There are roller vane pumps you can mount remotely - see the Metro Turbo. The return can just be Tee'd into the pipe between the tank & pump. I'd still go for an injection Mini tank if you can.

thanks for the advice, would this mean just the injetion tank and another line being run on the car? or is it more complex that this?

[Ethel]

You'll need a return line either way. The (Metro Turbo) pump I'm using has a 10mm input, so there's some juggling of adapters and hose sizes needed.

Have look for a parts catalogue online (Bosch) to compare the specs of the Micra pump with any likely alternatives.