4 replies to this topic

[maph2]

i was wondering if i could get the opinions of other forum users that are dabbling with megasquirt fuel injection on their minis.

1) which would be better - using a minispares 1 3/4 inlet manifold with a jenvey throttle body (about 48-52mm with single injector) OR a complete mpi injection unit? a second hand mpi unit may be cheaper but a single throttle body would look neater and less bulky.
2) from your experience, what cars can provide the necessary parts such as fuel pumps, fuel pressure regs, sensors etc?
3) my engine is a low mileage early 1990's non cooper 1275 with stage 1 kit, hif 44, kn pancake and 1.5:1 rockers, currently producing 68bhp at the fly. prior to the megasquirt i want to fit a modified cylinder head and a more aggressive cam - which cam should i go for, taking into account that fuel injection tames traditionally "lumpy" cams - a 286, 296 or an SW5?

thanks
matt

[Oldskoolbaby]

I thought that the sw5 cam was fairly mild cam but it might be nice with a well set up throttle body. If the head was further modified like you said I would may be go for something like 286. Id say thats halfway between smooth and lumpy and should give you a nice punchy engine. A 296 may be overkill.
Only wondering but have you considered a scatter cam. Dont quote me but one of them might give some nice engine characteristics given the mods your planning. You might beable to program the rough idling out of one of them and turn it into a baby cat Who knows?

[Woody]

I have gone for a twin 40 throttle body (weber patern)
the injection pump is fitted inside the fuel tank on injected minis so that is what i have gone for .
I havent got the megasquirt ecu yet as i am looking for someone to build it up for me .
i have been reading about the problem of charge robing (after i have bought the above set-up) and Dave Walker says the best way to do it is with a single throttle body (rover 25/mgf etc) on a long inlet .
i have read thet the sw5 cam is available in a special injection form .
but i was thinking that a scatter cam may help with the problem of charge robbing .

[maph2]

a scatter cam would be interesting but maybe not worth the expense or the chance it may not work well (as keith calver states). the situation i have is that i just want to make the most of what i already have and going down the megasquirt route is pretty cost effective.

my engine is pretty standard apart from a stage one kit, hif44 and 1.5:1 rockers. currently at 68bhp at the fly, with fuel injection i could get that up to around 90bhp. with a decent head and sportier cam it would be little bit more. i could go for a fully rebuilt 1293 etc but my current engine and box have only done about 28,000 miles.

i will be contacting simon at morspeed with the intent to have a new head, cam, lightened flywheel, vernier timing set up and a cross pin diff. i'll get him to set it up on the carb then fit the fuel injection at home. will be interesting to see the difference.

yes - will most likely get an mpi fuel tank - any thoughts on wiring for the fuel pump?

matt

[Woody]

as far as i know the pump just gets wired to an ignition live , i was thinking of fitting a switch from in the boot of a sierra injection , switches off in an impact .