[Kerry]

Would an lt1 hpfp with a bigger cam fuel lobe get close to the out put of an lt4 pump with a stock fuel lobe?

[Joshinator99]

Originally Posted by Kerry

Would an lt1 hpfp with a bigger cam fuel lobe get close to the out put of an lt4 pump with a stock fuel lobe?

Problem there is the LT1 HPFP typically operates at 2175 psi whereas the LT4 HPFP runs 2900 psi. So you’d need bigger injectors to compensate for the lower pressure. And if you have larger injectors then you’d want the LPE pump anyway to get the most out of them. I only run 2175 psi but have the LT4+52% injectors & LPE BB HPFP… always a balancing act.

[laynlo15]

Kerry, why don't you just get the TooHighPsi port injection, run E and you can turn down your High and low side and you won't have to worry again. Run about 70 percent DI and 30 percent PI.

[Kerry]

Originally Posted by laynlo15

Kerry, why don't you just get the TooHighPsi port injection, run E and you can turn down your High and low side and you won't have to worry again. Run about 70 percent DI and 30 percent PI.

Im not worried about a thing. I dont want to be e85 dependent. I have plenty of head room on 93 and meth. 3.8 to 4.1 ms at over 900 wheel. Low and high side holding fine, at 75psi and 2900.

Both my low side was dropping JMS booster fixed that. Then the high side was dropping but lt4 pump and injectors fixed that.

have a stock cam so always trying to learn and experiment. its a hobby.

No doubt the toohighpsi port is the bomb. very good option but at my power and set up I just dont need it.

hence my question is would the lt1 pump with cam lobe do as well as lt4 with stock lobe.

it would be great very helpful if someone could answer that. I would have to change the cam to really anser that. It aint that much of a hobby LOL.

Being I put in the lt5 cam as I like stock valve train, and wanted to do away with the dod system. and whoever said that it was same as lt1 cam just not dod. Now BTR says its more like an lt4 cam. So I would think the lt1 spec cam they have would work better for me with the lobe.

Then i would not need the lt4 pump sell that pays for the upgrade.

[Joshinator99]

Originally Posted by Joshinator99

Problem there is the LT1 HPFP typically operates at 2175 psi whereas the LT4 HPFP runs 2900 psi. So you’d need bigger injectors to compensate for the lower pressure. And if you have larger injectors then you’d want the LPE pump anyway to get the most out of them. I only run 2175 psi but have the LT4+52% injectors & LPE BB HPFP… always a balancing act.

Originally Posted by Kerry

hence my question is would the lt1 pump with cam lobe do as well as lt4 with stock lobe.

it would be great very helpful if someone could answer that. I would have to change the cam to really anser that. It aint that much of a hobby LOL.

Maybe you missed my post…?!? I did answer it. The answer is no because of the significantly lower pressure.

[Kerry]

Originally Posted by Joshinator99

Maybe you missed my post…?!? I did answer it. The answer is no because of the significantly lower pressure.

Well u may be correct but the lt1 will do 2900 until it runs out ie does not matter if its set to 2100 or 2900 runs out about the same place.

And u can turn the pressure in a middle ground as well. So i don't know.

pump can drop to 2500 and still i have plenty of fuel but much lower is a no no. Thanks for ur reply. Any help is much appreciated!

[Joshinator99]

Originally Posted by Kerry

Well u may be correct but the lt1 will do 2900 until it runs out ie does not matter if its set to 2100 or 2900 runs out about the same place.

And u can turn the pressure in a middle ground as well. So i don't know.

pump can drop to 2500 and still i have plenty of fuel but much lower is a no no. Thanks for ur reply. Any help is much appreciated!

LT1 pump is not recommended to run at 2900 psi… those who do so probably don’t do it for long IMO. And keep in mind asking any pump to move much higher pressure drops the fuel volume. If your injectors are big enough, then the lower pressure is worth the trade off for more pump volume.

[Kerry]

Originally Posted by Joshinator99

LT1 pump is not recommended to run at 2900 psi… those who do so probably don’t do it for long IMO. And keep in mind asking any pump to move much higher pressure drops the fuel volume. If your injectors are big enough, then the lower pressure is worth the trade off for more pump volume.

Yea 2900 out of that lt1 pump is asking a lot.

The car runs like better than i ever hoped someone help me to just let it alone.
::

raped ape scaled dog ect ect.