[Indypete]

Hey guys. Will the stock fuel system be able to handle running a stock LT4 (stock pulleys) AND E85? Not looking to boost past stock and I'm about to start the swap. I want this thing to survive a 500 mile roadtrip out to the roadcourse, a 3 day track event and the drive back.

Maybe a mix of E85 and pump 93? Curious where the limit would be vs ethanol content if anyone knows.


Cheers,
Pete

[biker2k]

im guessing no way fuel system keeps up with that, and if it does you will be at the limit which is never a good idea...

getting it tuned right?

[Joshinator99]

Adding a PD blower will max out an LT1 fuel system on 93, nevermind E85. Adding the LT4 fuel system will let you run some E, but probably just a blend of somewhere in the E30-E40 range if you’re staying at low boost.

[wnta1ss]

Looks like a bad idea to me. LT1 fuel sometimes cannot even keep up with a base kit on pump E10, and the LT4 pullies that you are using might mean 10~11psi of boost. At least I think that is what ZL1 guys say? WAY too much for stock fuel in my opinion, then E85 makes it even more ridiculous. I also think that running this much boost on a stock LT1 for a 3 day road course event will be pretty risky. These things don't like heat and you'll build plenty of it doing that kind of driving.

[Indypete]

Originally Posted by wnta1ss

Looks like a bad idea to me. LT1 fuel sometimes cannot even keep up with a base kit on pump E10, and the LT4 pullies that you are using might mean 10~11psi of boost. At least I think that is what ZL1 guys say? WAY too much for stock fuel in my opinion, then E85 makes it even more ridiculous. I also think that running this much boost on a stock LT1 for a 3 day road course event will be pretty risky. These things don't like heat and you'll build plenty of it doing that kind of driving.

Wow, I didn't realize boost would be that high. I thought it would the 6-7 psi range. That was what I was shooting for. Sounds I will need to get a bigger upper pulley to tame it.

Thanks for the input guys!

[wnta1ss]

Originally Posted by Indypete

Wow, I didn't realize boost would be that high. I thought it would the 6-7 psi range. That was what I was shooting for. Sounds I will need to get a bigger upper pulley to tame it.

Thanks for the input guys!

The LT4 has a lower compression ratio, and therefore it needs more boost than an LT1 would to make the same power. So while the base sc kits made for an LT1 motor probably would be in the 6~8psi range, I don't believe that's the case for the factory LT4 pullies. You could try finding out what pullies ADM or Weapon-X use when they put an LT4's blower onto a stock LT1 motor to get the 6-7psi of boost that you wanted.

[Eldi Z]

I think that the stock Pulley on the LT4's blower unit provides ~ 9 PSI boost. If ignition timing is not advanced too far, then 93 pump can be made to work pretty safe ~ 550 RWHP.
There are a bunch of tuners here with a lot of experience on this setup and can comment on the safe limits on the LT1 stock motor for your planned application.
Adding the LT4 fueling components would be another recommended safety measure.

[oldman]

second hand lt4 pump and lt4 injectors, lt4 low side pump are minimum upgrades IMO if you are going to tune for E.

[EDFHOBBIES]

If you have the LT4 fuel parts and a DSX lowside or boosta pump. you can tune probably on E50. but never full e85. you will be constantly keeping up with how much e you put in.

[KingLT1]

You need LT4 fuel system to run E85. At 5psi you can likely run full E85, at the 8-9psi you will be limited to E50- E60 which is all you need to get the benefits of E anyway.

ADM performance has a lot of info on the topic.

https://www.camaro6.com/forums/showthread.php?t=528126
https://www.camaro6.com/forums/showthread.php?t=527512
https://www.camaro6.com/forums/showthread.php?t=475479
https://www.camaro6.com/forums/showthread.php?t=444241

[TJay74]

Originally Posted by EDFHOBBIES

If you have the LT4 fuel parts and a DSX lowside or boosta pump. you can tune probably on E50. but never full e85. you will be constantly keeping up with how much e you put in.

I have this part down "PAT", very simple to track with either HP Tuners or the Torque App and a OBD2 reader. All I need to know is what my current Ethanol rating is and how much fuel the car has left, from that I can determine how many gallons of E85 will raise the Ethanol to the rating I want in the car.

I even made an Excell spreadsheet to calculate it for me.


As far as the LT4 supercharger on a LT1, you are going to be maxed on the LT1 fuel system on 91/93 octane. If you want to run E85 at all you will need the full LT4 fuel system and the fuel lines. Even then the max you will be able to run is around E40-E55 depending on who tunes the car for you.

[KingLT1]

It depends on the boost level...with the stock LT4 pulley(9psi), yes I agree, however you can run a larger pulley. ADM was able to run full pump E85 with 2.9 pulley(5-6psi) with the LT4 supercharger and fuel system on a 1LE. First link I posted

OP would be better off to run the larger pulley and E85. It produces a better power curve and less heat. Also no need to worry about mixing formulas, just pump and go. It makes better power and less heat then the stock pulley on 93.

[JANNETTYRACING]

Originally Posted by Indypete

Wow, I didn't realize boost would be that high. I thought it would the 6-7 psi range. That was what I was shooting for. Sounds I will need to get a bigger upper pulley to tame it.

Thanks for the input guys!

Let me clearify this for you.

YOU CAN NOT!!!!! RUN BOOST AND E-85 ON LT1 FUEL SYSTEM.

You should not even consider a blower and E without also including a ZL-1 in tank pump LT4 high pressure pump, and LT4 injectors.

Ted.

[MP3BOOSTED]

OP don't go the cheap way out, many of us have learned the hard way. Do your research on the pros and cons of boosting an LT1 and or the issues LT4 owners have ran across throughout these years. It took me a whole year after doing research to finally start my install of my boosted parts. their is many many things out there you will need for your car for it to run properly. Throw a cheap build at it and get a cheap return out of it. I also use the term "cheap" lightly.