18 LT4 Corvette Fuel System Upgrade, without meth?

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08-17-2023
kanders

18 LT4 Corvette Fuel System Upgrade, without meth?

I'm looking to do a cam/larger blower on my 18 LT4 Corvette. I'm not keen on meth for a couple of reasons and do not want to use an aux pump. Eventually will be aiming for 700-800rwhp on E85.

Has anyone used the following injectors & pump set up?

https://weaponxmotorsports.com/colle...nt=37646251985

https://www.foreinnovations.com/product_p/78-200.htm

Is there a better injector that is more reliable/tuneable? What other type of fuel pump mods would I be in for? Thanks in advance.
08-17-2023
TriPinTaZ

FIC's are garbage and often misfire over 2600 PSI. XDI's are much more reliable and easier to tune.
08-17-2023
GHuggins

If you've got the money they make +65 injectors then combine that with the big bore hpfp and you'll be fine for whatever E you want to run with the bigger blower and better low side.
08-18-2023
STAGEUP

When did we ever imagine injectors and a pump costing as much as a decent short block? LOL!!
08-18-2023
GHuggins

Quote:

Originally Posted by STAGEUP

When did we ever imagine injectors and a pump costing as much as a decent short block? LOL!!

I know right? Reason a few of my customers are considering port injection. Injectors alone almost 4000, but that depends on brand and size then the low side tickling 3000 and of course the pump.
08-18-2023
TriPinTaZ

yeah the prices have gotten ridiculous, heck they were already ridiculous. The LPE's are hard to come by because there is a shortage in LT1/LT4 fuel pumps as a whole(allegedly).
08-18-2023
Joshinator99

Quote:

Originally Posted by TriPinTaZ

yeah the prices have gotten ridiculous, heck they were already ridiculous. The LPE's are hard to come by because there is a shortage in LT1/LT4 fuel pumps as a whole(allegedly).

Yeah the LPE unit starts life as a brand new LT1 HPFP so any shortage there means tough sledding for LPE. Glad I got mine back before the price virtually doubled…!
08-18-2023
TriPinTaZ

Quote:

Originally Posted by Joshinator99

Yeah the LPE unit starts life as a brand new LT1 HPFP so any shortage there means tough sledding for LPE. Glad I got mine back before the price virtually doubled…!

Same! I'm trading in my Z06 for a 2023 ZL1. I took my LPE and XDI's off the Z06 today so I could use them on the ZL1. I bought both right before they hiked the prices and had to wait 6 months on the LPE and 2 months on the XDI's.
08-18-2023
regorih

How about port injection from 2highPSI, a DSX lowside, and the factory LT4 system and you can support 900rwhp on full e85 content? Its doable
08-19-2023
TriPinTaZ

Get the right injectors for the 2HPSIand you should. Also, get the upgraded DSX low side pump.
08-22-2023
h2.4

Too High Psi port injection. They have a controller that parallels in. I think the Dsx Aux pump can feed the port injection. There was word that they were talking to HpTuners to get their controller supported, but not sure if it is in the works or not.
08-23-2023
Alvin

Quote:

Originally Posted by TriPinTaZ

Get the right injectors for the 2HPSIand you should. Also, get the upgraded DSX low side pump.

Are these aux kits better than they used to be?

I've had a few too many cars that have pressure spikes both high and low with his old hobbs switch/delayed off setup. Especially manuals.. I'm reluctant to try another one. Maybe that new controller fixes this?
08-23-2023
TriPinTaZ

Quote:

Originally Posted by Alvin

Are these aux kits better than they used to be?

I've had a few too many cars that have pressure spikes both high and low with his old hobbs switch/delayed off setup. Especially manuals.. I'm reluctant to try another one. Maybe that new controller fixes this?

You can ramp the injectors in to avoid smacking it will a ton of fuel right away.
08-23-2023
radz28

My TooHighPSI PI comes in smooth enough I can't tell when it comes in.
08-23-2023
Alvin

I'm not talking about the point injection.. I'm talking about the aux pump spiking fuel pressure when you lift off the gas or when you short shift a blower car.
08-23-2023
TriPinTaZ

Quote:

Originally Posted by Alvin

I'm not talking about the point injection.. I'm talking about the aux pump spiking fuel pressure when you lift off the gas or when you short shift a blower car.

Hasn't really been an issue on the dozens and dozens of cars I've tuned for the DSX Low Side. There are some things that need to be done in the tune and they are different between cars that use the CAN bus to activate or the MAP signal to activate. That's been my experience at least.
08-23-2023
Alvin

Thank you.. I appreciate it.
08-26-2023
1scls1z

Quote:

Originally Posted by Alvin

I'm not talking about the point injection.. I'm talking about the aux pump spiking fuel pressure when you lift off the gas or when you short shift a blower car.

On the cars I have worked with it hasn't been an issue.
08-27-2023
GHuggins

Quote:

Originally Posted by Alvin

I'm not talking about the point injection.. I'm talking about the aux pump spiking fuel pressure when you lift off the gas or when you short shift a blower car.

Alvin's referring to the secondary pump kicking on full bore with the fpcm and check valve on the primary being the only thing to control it. I could see this being an issue with port addition unless the DI side is enough to absorb it, which I guess in this case it does. Haven't done a port/DI combo yet to know myself. I did just refuse tuning a 4th gen for this very issue where a secondary pump was coming in full bore with only the fpcm and 30psi check valve on the primary side to control it. No Di in this case to absorb any and I wasn't about to risk blowing a motor due to sticking injectors or wildly fluctuating fuel pressure...

Does anyone have a log with a port/Di setup that they would mind posting with fuel pressure logged in it? I've seen over 85psi on like setups on DI only's, so was wondering what the combo would show.

Of course then again isn't ID making injectors that still open at really high pressures now too? If so that would alleviate the concern as long as those were used.
08-28-2023
TriPinTaZ

Quote:

Originally Posted by GHuggins

Alvin's referring to the secondary pump kicking on full bore with the fpcm and check valve on the primary being the only thing to control it. I could see this being an issue with port addition unless the DI side is enough to absorb it, which I guess in this case it does. Haven't done a port/DI combo yet to know myself. I did just refuse tuning a 4th gen for this very issue where a secondary pump was coming in full bore with only the fpcm and 30psi check valve on the primary side to control it. No Di in this case to absorb any and I wasn't about to risk blowing a motor due to sticking injectors or wildly fluctuating fuel pressure...

Does anyone have a log with a port/Di setup that they would mind posting with fuel pressure logged in it? I've seen over 85psi on like setups on DI only's, so was wondering what the combo would show.

Of course then again isn't ID making injectors that still open at really high pressures now too? If so that would alleviate the concern as long as those were used.

I sent you over an email with some logs