Author Topic: Injector size for DA supercharger (Read 8216 times)

Bill K · « **on:** June 13, 2010, 06:42:54 AM »

I have just fitted a DA supercharger kit to my 1995 M42 318is but am disappointed at the power output - only 108kw at the rear wheels after the factory chip has been re-tuned by an experienced BMW modifier, a long way short of the 170hp (about 127kw) claimed by the maker and reported by others who have done the DA conversion. My car has done 208,000km but my local BMW shop advised the engine is in good condition and had typical performance for a stock 318is. However, I notice that the performance graphs are usually reported for M44-engined cars as fitted to later 318is� and Z3�s and when ordering the kit the maker advised that M42�s for my country (Australia) use a fuel injector that requires a 14mm hole in the manifold whereas US-market M42�s use an injector that requires a 17mm hole, the same as M44�s. Can anyone please advise the specs (flow etc) for the early and late injectors as it may be that the car needs more fuel flow to take full advantage of the 7.5 psi max boost. Otherwise I am very pleased with the kit as it is of factory standard in appearance and has retained all the smoothness of the standard engine when operating at light throttle openings.

bmwconnect · « **Reply #1 on:** June 13, 2010, 09:24:49 AM »

The chances he tuned the motronic 1.7.2 correctly is very slim. currently there is only a few big name company's and a hand full of people that know how to tune this motoronic version for boost. Are you able to get the modified file off the chip? I can look it over and tell you if its been done correctly

Bill K · « **Reply #2 on:** June 30, 2010, 11:28:34 PM »

Thanks for the response. I cannot get the modified file off the chip but will try to find a way. I have a high level of confidence in the work of the tuner as his business revolves around fitting superchargers or turbochargers to BMW's for road and/or track work. He also maintains/rebuilds a few successful ex-BMW factory racers including Super Tourers and cars he works on have good reliability records. His own road/race car is a 1995 318ti with a turbocharged engine putting out around 280kw at the rear wheels.
Assuming the tuning is OK do you have any suggestions about changes needed to take best advantage of the SC (larger exhaust??). Unfortunately I live some 300km away from the nearest city where BMW tuners operate so it is not easy to take the car for diagnostics. My regular service (BMW Master Technician) says the standard car performed like a typical 318is. Any advice would be greatly appreciated.

bmwconnect · « **Reply #3 on:** July 01, 2010, 12:06:30 AM »

Quote from: Bill K;94117

Thanks for the response. I cannot get the modified file off the chip but will try to find a way. I have a high level of confidence in the work of the tuner as his business revolves around fitting superchargers or turbochargers to BMW's for road and/or track work. He also maintains/rebuilds a few successful ex-BMW factory racers including Super Tourers and cars he works on have good reliability records. His own road/race car is a 1995 318ti with a turbocharged engine putting out around 280kw at the rear wheels.
Assuming the tuning is OK do you have any suggestions about changes needed to take best advantage of the SC (larger exhaust??). Unfortunately I live some 300km away from the nearest city where BMW tuners operate so it is not easy to take the car for diagnostics. My regular service (BMW Master Technician) says the standard car performed like a typical 318is. Any advice would be greatly appreciated.

yet he can't explain to you why your only making 108Kw at 7.5psi... Makes no sense to me. What size of injectors are you running? throwing any CEL's for knock sensors ?

Bill K · « **Reply #4 on:** July 02, 2010, 01:52:54 AM »

I also was dissappointed at the lack of interest by the tuner in analysing my car's low power output. I made a 6-hour round trip journey to have the chip re-tuned during a morning appointment so I suspect he ran out of time and wanted to get onto more interesting projects.
My car uses the standard injector for a 9/95 build car; that is the brown 14mm unit. Jim Roe of DA told me he needed to supply a manifold with 14mm injexctor holes as the US M42's used a 17mm unit (like the M44). I think they have provision for an air pump that is not used on the Australian-spec cars.

bmwconnect · « **Reply #5 on:** July 02, 2010, 07:56:14 AM »

Quote from: Bill K;94175

I also was dissappointed at the lack of interest by the tuner in analysing my car's low power output. I made a 6-hour round trip journey to have the chip re-tuned during a morning appointment so I suspect he ran out of time and wanted to get onto more interesting projects.
My car uses the standard injector for a 9/95 build car; that is the brown 14mm unit. Jim Roe of DA told me he needed to supply a manifold with 14mm injexctor holes as the US M42's used a 17mm unit (like the M44). I think they have provision for an air pump that is not used on the Australian-spec cars.

ya we have shrouded injectors here but man if your still using stock injectors this tuner is a fool and ripped you off...A tuner would never tune stock injectors or with a RRFPR in place for boost lol

HaNasich · « **Reply #6 on:** July 09, 2010, 05:46:00 PM »

Hi
i also have a M42 (engine is 1995 harvest

)with DASC on it.
i use stock motronic ECU (from 1990 E30 IS) and SAAB 900 injectors.
performance are fine.
did u check wide band sensor reading / do u have any?

nickmpower · « **Reply #7 on:** July 09, 2010, 05:50:01 PM »

Quote from: HaNasich;94476

Hi
i also have a M42 (engine is 1995 harvest )with DASC on it.
i use stock motronic ECU (from 1990 E30 IS) and SAAB 900 injectors.
performance are fine.
did u check wide band sensor reading / do u have any?

do you have trouble with knocking? I did, even when my AFR was spot on, so i had to dial the ignition timing back

deekay · « **Reply #8 on:** July 09, 2010, 07:40:11 PM »

don't bother with whatever the stock injector size is (19lb/hr for USDM, but that's not enough for what you're doing)-

i'm gonna hazard a guess that if you're expecting 170hp out of this thing, you're gonna need at least 24lb/hr injectors. VAC motorsports sells them, which is where i got mine for my ITB setup.

HaNasich · « **Reply #9 on:** July 10, 2010, 09:31:18 AM »

Quote from: nickmpower;94478

do you have trouble with knocking? I did, even when my AFR was spot on, so i had to dial the ignition timing back

at first, with stock injectors - i did have knocking problem.
i tried using better fuel (98 octane instead of regular 95) and it did the trick most of the time.
but final answer to knocking was changing injectors to SAAB 900 turbo ones, which rate 220 instead of the stock 180 injectors.
now my car runs pretty reach most of the times.

another solution can be moving on to >1993 CPU which support knocking sensors and can compensate ignition timing better than pre 1993 ECU - of course this only applies if ur engine block is post 1993 and support knock-sensors as well harness and ECU support those as well.

bmwconnect · « **Reply #10 on:** July 10, 2010, 10:49:25 AM »

Quote from: HaNasich;94497

at first, with stock injectors - i did have knocking problem.
i tried using better fuel (98 octane instead of regular 95) and it did the trick most of the time.
but final answer to knocking was changing injectors to SAAB 900 turbo ones, which rate 220 instead of the stock 180 injectors.
now my car runs pretty reach most of the times.

another solution can be moving on to >1993 CPU which support knocking sensors and can compensate ignition timing better than pre 1993 ECU - of course this only applies if ur engine block is post 1993 and support knock-sensors as well harness and ECU support those as well.

or you can do thing's correctly and delete the RRFPR get 30LB injectors and a proper tune and make 200whp@10psi

HaNasich · « **Reply #11 on:** July 11, 2010, 07:50:45 AM »

Quote from: bmwconnect;94500

or you can do thing's correctly and delete the RRFPR get 30LB injectors and a proper tune and make 200whp@10psi

Please elaborate - i'd love to hear more about that

the RRFPR is nothing im too fancy about it.
i'd love to get rid of it - it catches police eyes and make nothing but trouble.
how can i stay with stock ECU and get rid of the RRFPR?

bmwconnect · « **Reply #12 on:** July 11, 2010, 08:58:30 AM »

Quote from: HaNasich;94544

Please elaborate - i'd love to hear more about that

the RRFPR is nothing im too fancy about it.
i'd love to get rid of it - it catches police eyes and make nothing but trouble.
how can i stay with stock ECU and get rid of the RRFPR?

You need to find a tuner that can work with BMW in your area and put in 30LB injectors. I have a 10psi turbo tune for that motor but it would be useless with the DA supercharger kit

deekay · « **Reply #13 on:** July 11, 2010, 05:22:21 PM »

Quote from: HaNasich;94544

Please elaborate - i'd love to hear more about that

the RRFPR is nothing im too fancy about it.
i'd love to get rid of it - it catches police eyes and make nothing but trouble.
how can i stay with stock ECU and get rid of the RRFPR?

...they pay more attention to the fuel pressure regulator than the supercharger?

HaNasich · « **Reply #14 on:** July 11, 2010, 06:06:09 PM »

Quote from: bmwconnect;94545

You need to find a tuner that can work with BMW in your area and put in 30LB injectors. I have a 10psi turbo tune for that motor but it would be useless with the DA supercharger kit

you might as well wrote
"leave the original ECU in place and put megasquirt in the trunk"

i was expecting a more technical answer.
i would like some guy to mess with my car without me knowing what he's doing (and the sense behind his actions)
at least with my RRFPR i can use wide band and fuel pressure indicator to find out how reach am i running

Do you know what injectors does SAAB 9000 2.0 turbo use? what fuel pump?