3800 Ye Olde 42# injector/no tune/E85 trick
- Thread starter v6buicks
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I say throw the injectors in it and see where the trims are at. With e85 and an intercooler I would think you'd be able to drop down a good bit depending on where the timing falls but as for specifics I'm not good on pulley sizes and there's a lot of variables.
Worst case you spend 100 bucks and unlock it really.
Worst case you spend 100 bucks and unlock it really.
Return less runs at 60psi I believe but it’s been a long time I can’t remember exactly, the difference comes in the regulator, the return system raises fuel pressure 1:1 with boost pressure the return less does not raise pressure
I gotcha. So I'm thinking about ditching the C30 because for about the same price as redoing the suspension I could probably score my buddies 04 Comp G.
It's been a few years since I've seen it because he lost interest and even listed it a couple times. However, I recall it having no rust but crappy paint and 160k miles. It has brand new refinished 10 spoke Comp G wheels (love those) with new tires. He did the F-body front brake upgrade, full stack intercooler, lots of very nice custom brackets to make that IC fit. It looks spotless under the hood, and should be mostly sorted. I don't think AC works, but everything was still there. Stock pulley and tune, but LS6 springs, modular hub, wideband, and Aeroforce. He did a ton of nice work to that car just to not pulley down or enjoy it. Thing is ready for fuckery, and I already have known good 42# injectors.
The bad is that we now know it doesn't start. The guy who owns it is an actual ex-Chevy dealer tech and thinks it needs a fuel pump, but he's lazy. Lol I figure it would need one anyway for what I wanna do with it. I just don't know the S3 returnless system like at all.
3.0 is just out of my own laziness because I have one. 3.2 or 3.3 would be more reasonable for someone who wants the transmission to survive. Lol
It's been a few years since I've seen it because he lost interest and even listed it a couple times. However, I recall it having no rust but crappy paint and 160k miles. It has brand new refinished 10 spoke Comp G wheels (love those) with new tires. He did the F-body front brake upgrade, full stack intercooler, lots of very nice custom brackets to make that IC fit. It looks spotless under the hood, and should be mostly sorted. I don't think AC works, but everything was still there. Stock pulley and tune, but LS6 springs, modular hub, wideband, and Aeroforce. He did a ton of nice work to that car just to not pulley down or enjoy it. Thing is ready for fuckery, and I already have known good 42# injectors.
The bad is that we now know it doesn't start. The guy who owns it is an actual ex-Chevy dealer tech and thinks it needs a fuel pump, but he's lazy. Lol I figure it would need one anyway for what I wanna do with it. I just don't know the S3 returnless system like at all.
3.0 is just out of my own laziness because I have one. 3.2 or 3.3 would be more reasonable for someone who wants the transmission to survive. Lol
Thats what I wondered because I'm sure I've seen some ls stuff that way. That puts a little different twist on it from a tuning aspect but where this is more or less manipulating what's there then probably not so much unless pressure is bumped beforehand to try and squeeze a little more.
The 04 should still have the fuel pump window hatch deal it was the last year for it I believe, it should have an external fuel filter also , there is a regulator but it’s in the fuel hat, the rest is pretty self explanatory one line to the rail same pump as the others if I remember right, not raising fuel pressure means you need more pump and more injector than the older cars
You can convert it to return fairly easy, I’m pretty sure I did a return system on my 04, it had dual pumps also
Sell em and buy 80s and a 450 pump, you'll be money ahead when your bored with the 42s and decide you wanna twin charge it
For what it's worth I'd imagine an older rail and lines wouldn't be hard to retrofit and the older canister style may even be drop in? Of course with a bigger than stock pump
Mark my words. Any FWD 3800 of mine will never be any more than a mild bolt-on daily driver.
But go ahead and save that statement above for future humiliation. ?
I just Rockauto'd the injectors. There's a different PN between S2 and S3 which is already making me think my idea is not super wise. Having a pump hatch is sweet though. If it's that easy to change the, I'd be more tempted to give this a try.
But go ahead and save that statement above for future humiliation. ?
I just Rockauto'd the injectors. There's a different PN between S2 and S3 which is already making me think my idea is not super wise. Having a pump hatch is sweet though. If it's that easy to change the, I'd be more tempted to give this a try.
04 and newer returnless are a 48 to 52 psi base pressure.
33lbhr not 36 like the l67....
But since the fuel pressure is higher at all points below atmospheric they act like 36s with low fuel pressure under vac of a return regulator
The pressure regulator being in the Hat means that during EVAP system leak test the fuel pressure will vary as the computer puts the tank under vacuum to check for leaks
To convert to return list just turn your current pressure line into the return and run a new pressure hose to the front to get rid of all the restrictive Quick Connect fittings. Either run it to a fuel pressure regulator with a deadhead Branch to the newer fuel rails or convert to the older rails with the flow through fuel.
Oscar went with deadhead to l32 rails to keep the pulsation dampers.
33lbhr not 36 like the l67....
But since the fuel pressure is higher at all points below atmospheric they act like 36s with low fuel pressure under vac of a return regulator
The pressure regulator being in the Hat means that during EVAP system leak test the fuel pressure will vary as the computer puts the tank under vacuum to check for leaks
To convert to return list just turn your current pressure line into the return and run a new pressure hose to the front to get rid of all the restrictive Quick Connect fittings. Either run it to a fuel pressure regulator with a deadhead Branch to the newer fuel rails or convert to the older rails with the flow through fuel.
Oscar went with deadhead to l32 rails to keep the pulsation dampers.
So with 93 octane and the stock 3.8" pulley on my daily I was seeing knock when the engine is heat soaked on a pretty regular basis. I'm running E85 now though with 60# injectors(tuned) and a 3.4" pulley and have never seen any knock whatsoever even on long road trips when everything is really heat soaked. I'm sure I could go down to at least a 3.25" but I'm scared to break my completely stock transmission on it.
You could probably run a 3.0 pulley, but if you decide to go up a size a hub and modular pulley is like $100.
If you still have DHP you could put whatever injectors into it you want without wasting HPT credits. You'll probably want to save this link though unless you're taking your laptop with you everywhere you go or unless you've dialed your fuel trims into the midpoint between 93 and E85:
I keep a google map of all of the E85 stations in the US in any place I've done a road trip in. A bit of an annoyance but it's not a big deal anymore to me.
You could probably run a 3.0 pulley, but if you decide to go up a size a hub and modular pulley is like $100.
If you still have DHP you could put whatever injectors into it you want without wasting HPT credits. You'll probably want to save this link though unless you're taking your laptop with you everywhere you go or unless you've dialed your fuel trims into the midpoint between 93 and E85:
I keep a google map of all of the E85 stations in the US in any place I've done a road trip in. A bit of an annoyance but it's not a big deal anymore to me.
Damnit. I really need to learn how to use DHP. I got another one for stupid cheap recently, but it's just the hardware. If anybody has a dropbox they can send me with all the DHP softwares, I'd really appreciate it!
I also just talked to my buddy and remembered that this car has a lot more than I even mentioned. ZZP downpipe, power logs, rebuilt trans, 1.9s.... with a fuel pump and a tune this thing would would rock. He told me that he only wants $1500. I just need to hope that it hasn't gotten rusty from sitting on gravel for the last few years.
I also just talked to my buddy and remembered that this car has a lot more than I even mentioned. ZZP downpipe, power logs, rebuilt trans, 1.9s.... with a fuel pump and a tune this thing would would rock. He told me that he only wants $1500. I just need to hope that it hasn't gotten rusty from sitting on gravel for the last few years.
One thing to remember with e85 is that it cools cylinder temps and masks detonation so well that if you do actually see knock your probably gonna have something broken.
Personally I would rather play on pump gas because you can get into a couple degrees without destroying something and know where to stop much easier whereas e85 you basically need a dyno to watch where you stop making jumps in power to get to mbt.
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