Cascade Crew

GREG DAVIDSON · Posted: Wed Mar 10, 2010 8:03 pm Post subject: My Daytona

k i dont want the HP thread to get jacked anymore so i'll start this one Razz

for all who was at dyno and read the hp post im running waaaaaaay to lean, any suggestions on where to start looking ? get a gauge on the schrater valve , maybe a fuel pump its way easy on this car i dont even have to drop the tank, bigger injectors ?

blue89 · Posted: Wed Mar 10, 2010 9:04 pm Post subject:

Yup, get your gauge on. That's where I'd start. Then check injector impedence. How does your factory O2 sensor compare to the wideband at the dyno?

fiveoformula · Posted: Wed Mar 10, 2010 9:04 pm Post subject:

Check your fuel pressure and check for vacuum leaks, hows it run?

GREG DAVIDSON · Posted: Wed Mar 10, 2010 9:06 pm Post subject:

runs fine i know i have vaccume issues but i dont think there to bad i'm going to be diving into it alot more come spring break next week

fiveoformula · Posted: Wed Mar 10, 2010 9:13 pm Post subject:

Got to take care of any air leaks to make the o2 happy

blue89 · Posted: Wed Mar 10, 2010 9:14 pm Post subject:

WOT is open loop so it would just come down to fuel delivery, ya? Maybe change the injectors for an upgrade and to ensure a good spray pattern.

fiveoformula · Posted: Wed Mar 10, 2010 9:23 pm Post subject:

I guess so, It would have to be fuel delivery problem with that logic. Would the stock injectors really be maxed out already with a little more boost? The Turbo's are multiport right?

GREG DAVIDSON · Posted: Wed Mar 10, 2010 9:55 pm Post subject:

for as little as i know about the top half of the engine, its a multi-port injection it had a throttle body with the injectors behind the head kinda

Alphius · Posted: Wed Mar 10, 2010 10:00 pm Post subject:

Injector impedance would be one of the first things I check. And make sure, if it has a MAP sensor that it is connected to an unported vacuum source on the engine. Since it was boosting 12-13psi on the dyno pretty well, I'd say the wastegate vacuum stuff is probably close enough to being correct.

It was leaner on the top end as well, ya? Fuel pressure gauge is another great place to look for problems as you crack the throttle and build boost. Maybe fuel pressure regulator is supposed to be boost-referenced and it's hooked up wrong? Make sure if your FPR has a vacuum port it is also connected to unported manifold vacuum.

It's close enough to stock boost that the injectors should definitely not be maxed out. Yank the injectors but leave them attached to the fuel rail and check the spray pattern on a chunk of cardboard placed under them maybe?

I typed this fast, let me know if any of it doesn't make much sense or if you need me to expand on anything.

GREG DAVIDSON · Posted: Wed Mar 10, 2010 10:08 pm Post subject:

whats the FPR ?

aaron_sK · Posted: Wed Mar 10, 2010 10:09 pm Post subject:

http://www.thedodgegarage.com/turbo_vacuum.html

As Gabe mentioned, the FPR is a good place to start poking around.

*Edit for ninja-ing:

Alphius · Posted: Wed Mar 10, 2010 10:11 pm Post subject:

GREG DAVIDSON · Posted: Wed Mar 10, 2010 10:14 pm Post subject:

allrighty i will check that , im thinking whatever is wrong would be under the hood just due to the fact that the guy i bought it from replaced the pump and filter, he told me he did and everything looks new to but i know there are lemon parts made

rjmcgee · The Hammer Joined: 08 Jan 2004 Posts: 2328

It's a 20 year old car, boosted or not I wouldn't do any mechanical work until a complete tune up was done. Ignition, filters, plugs, wires, and anything else that is a wear item. Then if it still doesn't run right start digging.

aaron_sK · Posted: Wed Mar 10, 2010 10:20 pm Post subject:

Greg, you might also want to take a look at this:

http://www.thedodgegarage.com/common_failures.html

Lots of fun failure points in those motors, apparently. Good thing I'm not much of a Mopar guy anymore. Razz

GREG DAVIDSON · Posted: Wed Mar 10, 2010 10:26 pm Post subject:

Twilightoptics · Posted: Thu Mar 11, 2010 7:25 am Post subject:

Alphius · Posted: Thu Mar 11, 2010 9:41 am Post subject:

izcain · Posted: Thu Mar 11, 2010 1:51 pm Post subject:

I agree with the fuel filter... Also check into what the impedence is. If the injectors are not totally tapped out yet I would get an adjustable FPR and see if you can get the pressure up a bit. Not the best way to do it but may work ok until you can save for some better things.

blue89 · Posted: Thu Mar 11, 2010 4:54 pm Post subject:

I'd replace the fuel filter only after you've verified that the fuel pressure lowers as you go idle to WOT or from idle to red line. No sense randomly replacing parts.