348 Fuel Injector Change Process?

Were Plugzit's 355 injectors pink on top? Those are the 1996+ 355/550 injectors (shown below):
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Jeez, you guys spend a lot of money on injectors. Have any of you thought about asking RC Egnineering for their price on injectors for your application? RC Engineering will clean and balance your stock injectors for about $30 per or they will whip up custom injectors to suit your application.

And has anybody got a reply to my comment that larger injectors without extensive engine modifications will make your engine run rich?

Scott

 

I really don't remember. Send Plugz a pm, he'll know for sure.

All I know as that they weren't spraying. You could grab ahold of them to feel if they were clicking open or not, and the 355 injectors weren't clicking, so they got swapped for the 348 injectors.

 

He's doing something with the MAF I'm sure to compensate . .. but your question is valid since I don't think the engine has any mod's . .. why wouldn't you just get the stock injectors cleaned and flowed?

 

ND . .. in the first post, you say you're upgrading you're fuel injectors . . . what is it you're expecting to improve if not the spray pattern? You have a lean condition or somehting?

 

Only at redline, and just a little bit, but I'm also working on better air flow into the intake, so I'll need more fuel at all rpms eventually.

I can bump up the injector-open times on the ECUs, but that starts cutting into the acceptable duty cycle for them...so higher fuel pressure or larger injectors are the obvious alternatives.

 

What duty cycle you seeing?

Are these cars full sequential fuel injection? You get less duty cycle with true full sequential 'cause the injectors only have to open and close once for every 2 engine rev's . .. was reading about late 80's P cars with Motronic (think this applied to 993's also which is same era as 348) and they were semi-sequential . .. doesn't seem like you're intersted in swapping ECU's but if it's not full sequential already just another reason to upgrade (well upgrade to me ).

 

reading over the weekend it seems sequential wasn't adopted until Motronic 3.0 . . did any 348's have 3.0?

 

Nope, 2.5 & 2.7 was it.

 

Article on getting larger fuel injectors to work: http://autospeed.com/cms/A_110359/article.html

 

How about and update. Are you still making progress on your injector change?

 

IIRC, Bruce is running Mustang 24 lb. injectors.