Injectors...."Pintle" or "Disc"....which is better?

[QWIKTURBO]

I am in the market for 50#ers. The MSD's are kindy pricy and Racetronix has a good sell going on with the Delphis I believe. Would the Delphis be worth the savings or just stick with the original plan and go with the MSD's? TIA

 

[TurboBeagle84]

i not 100% sure on this but the pintle style injectors are subject to more wear than disc and also i heard the disc type injectors can be cleaned better than pintle style. i have thought about using the delphi 37# injectors when i upgrade to a ta49 turbo soon.

 

[d0n_3d]

racetronix has a sale going on with the 42.5 lb/hr DISC injectors and the delphi 50 lb/hr PINTLE injectors...

i thought those 50's where disc design? or are these delphi injectors different from MSD 50's??? are the MSD 50's a disc design???

 

[Steve Wood]

I believe Delphi and MSDs are the same injector.

 

[QWIKTURBO]

Hmmm....

So ya'll think the Delphi and MSD's are the same "design"...being pintle? If so...I'm gonna go with the Delphis then. Aren't the stock injectors "pintle" type as well? They seem to do pretty well as far as wear goes. Any other input is welcome. TIA

 

[c&cgn]

Re: Hmmm....

Originally posted by QWIKTURBO
So ya'll think the Delphi and MSD's are the same "design"...being pintle? If so...I'm gonna go with the Delphis then. Aren't the stock injectors "pintle" type as well? They seem to do pretty well as far as wear goes. Any other input is welcome. TIA

I don't think Steve was saying the same "design", he is saying they are the same injector, period. As far as I know the 50's are all made by Delphi and some are packaged as MSD's.

Stock injectors are pintle as well. Despite what some ad's say about Disc being better than Pintle, I really don't know which is better, but I can tell you that the best injectors I have used have all been pintle: Stock, bluetops and 50's (MSD's if you will).

 

[Red Canyonero]

MSD and Delphi injectors are the same, and they aren't disc or pintle.

They use a ball and seat design. I'm not sure of the ramifications/strengths/weaknesses of this design, but i'm pretty sure it is the main reason these injectors don't like 90+ psi. Probably also the reason they have great linearity for such a big injector.

Brian Green
89 TTA

 

[QWIKTURBO]

Cool....

Thanx guys for the info. I learned something new today thanx to ya'll! Looks like its off to Racetronix website!

 

[Racetronix]

Delphi bought out Lucas a while back.
The Delphi Multec race injector line which the 50's are a part of are classified as pintle injectors (according to Delphi). These injectors use a ball / seat design to control fuel flow.

The Lucas injector is a disc injector and is not the same as the Delphi Multec series injector.

If you ECM/chip is calibrated properly both styles will exhibit excellent drivability and performance in a TR.

Jack
Racetronix

 

[Red Canyonero]

Nifty link here. http://www.supras.com/~riemer/sonictech/fuel_injectors/RCtech.html

Some good data about different brands & makes. They classify the Delphi's different than the disc or pintle... seem to have several different classification types.

Anyways, another interesting note was the Indy car injector info, talking about a stream. The newer PFI cars out there have been using similar injectors - LS1, GTP - have pencil stream injectors, running sequential fueling. They are probably achieving the same results as the Indy cars by spraying a fine stream on the back of the intake valve.

Brian Green
89 TTA

 

[bruce]

Originally posted by Red Canyonero
The newer PFI cars out there have been using similar injectors - LS1, GTP - have pencil stream injectors, running sequential fueling. They are probably achieving the same results as the Indy cars by spraying a fine stream on the back of the intake valve.

It's not a matter of the fine stream, it's a matter of getting as much fuel as possible on the back of the intake valve.

Ball and seat, pintle, disc, the differences are mostly if you're selling a couple million cars and trying to keep the EPA happy. Or, running an insanely large injector, and trying to get a 700 RPM idle.