[Choda]

love these threads. Sucks I didn't know about the +43 cam when I built my motor. I believe I have the +38. Can the +43 lobe be used with the lt4 hpfp?

[KingLT1]

Originally Posted by Choda

love these threads. Sucks I didn't know about the +43 cam when I built my motor. I believe I have the +38. Can the +43 lobe be used with the lt4 hpfp?

No...38% is max with LT4 pump.

Originally Posted by F419sr1

I don't know much about tuning and pressures. I was told going to a lower pressure with a larger injector is like a wash and I wouldn't gain anything. That's the way I understood what I was told. It's also possible I miss understood what he was explaining. Either was the take away was it wasn't worth doing. I had ordered a big bore pump and sent it back.

Not necessarily....If you are running out of high or low side like my brothers car was from not having a large enough fuel lobe or enough low side then you can lower rail pressure to take strain off the fuel supply. The injector pulse widths will widen in exchange.

For example: On the C7Z with +30 injectors running 2900psi with the same cam, high and low side, the setup was maxed around E40. Going to +65's and lowering rail allowed the Ethanol content to be increased back up to E65. So far from a wash but not exactly a home run either being the E content still has to be blended. The goal was to be able to stay around E60 as that is the sweet spot for Ethanol.

If the setup had a +43 cam or secondary hpfp it would likely be able to run close to full E. But again the only point in running full E is simply for the convenience of not needing to blend. It doesn't gain much else vs E60.

[Joshinator99]

Originally Posted by F419sr1

I don't know much about tuning and pressures. I was told going to a lower pressure with a larger injector is like a wash and I wouldn't gain anything. That's the way I understood what I was told. It's also possible I miss understood what he was explaining. Either was the take away was it wasn't worth doing. I had ordered a big bore pump and sent it back.

Yeah that guy was wrong lol. Volume is the key, not pressure. And pressure to volume is not a 1 to 1 ratio. Big bore HPFP moves more fuel at 2175 psi than LT4 HPFP does at 2900.

[F419sr1]

Originally Posted by Choda

love these threads. Sucks I didn't know about the +43 cam when I built my motor. I believe I have the +38. Can the +43 lobe be used with the lt4 hpfp?

I didn't know there was a line that large either. Iv heard of 38%. Sometimes I think these shops don't tell you so when you want to take it to the next level they can charge you again

[Dan82679]

I had the XDI pump..Don't do it. It's very expensive(plus you gotta buy the injectors),ton of belt slip and you gotta change the oil in the pump every 1000 miles. I eventually went port injection for 1/4 of the price and it is super reliable.

[Joshinator99]

Originally Posted by Joshinator99

Ok, I got you there too. My brother was going that direction with his 880 WHP Z06 and traded a ton emails with Uwe and his minions. They (XDI) admitted that you have to check this pump constantly, and that they had a ton of failures in the past. They’ve tried some different stuff as of late, but didn’t want to sell it anyone unless they were already running XDI injectors and agreed to essentially be a Guinea pig with the pump update of the month… he was stunned at how unpolished the XDI pump was and ended up backing out to go port injection.

Originally Posted by Dan82679

I had the XDI pump..Don't do it. It's very expensive(plus you gotta buy the injectors),ton of belt slip and you gotta change the oil in the pump every 1000 miles. I eventually went port injection for 1/4 of the price and it is super reliable.

Well…that confirms that lol.

[F419sr1]

Originally Posted by Joshinator99

Well…that confirms that lol.

Thanks.

[EDFHOBBIES]

Could be miss information, but I was over Sorian's Tuning and JR came in while Matt was on a test drive with my car He said he had a failure on an XDI pump and Uwe told them just to bolt the oem LT4 pump to their belt driven system.

Only the C7 vette on katech's video ad and the Jannetty zl1 are the only 2 builds I have seen. I figured Dailey ZL1 youtube guy was going to get it since he had katech do his work but no just another high dollar 800 hp motor with no attention to fueling

When I did my setup I was offered the XDI at cost pretty damn cheap. However it was uncharted territory and we knew port worked all ready so no reason to take a chance. Even at cost it still was more than Haltec's ecu, ID1050s, and crawfords machine work.

I'll be honest I've had to do some retunes on the DI/port setup just to make the port transition smoother i was seeing a little hesitation/stumble sometimes right when it comes on I'm scheduled to get a 2nd map installed to help instead of ipw based operation of the TPS. Some of the problems are going from atmosphere to a lot of boost, transition from 30/40% ve toi 100++. I was a little frustrated and asked Matt about pulling the port of and tryin the XDi stuff he was not found of it probably from the car Jrod brought him.. pretty much to the point he didn't want to touch it if I did that.

Honestly I'm surprised DSX hasn't built something to compete with XDI and more dependable.

I'm damn near tempted to cut a fuel lobe off a cam, drill the center out to install a shaft, fit 2 bearings on it and a pulley, and build a case for the pump to sit on. after that is some fuel lines and wire harness to other pump.

wow didn't know about the 1000 mile oil change.. surprised they didn't pump motor in there box and gravity feed it back to motor.

[Katech_Mike]

We were involved in the development/testing of the original XFP kits. We have installed quite a few of them.

The 1st iteration of the Camaro kit did have belt slip. The brackets were revised and the belt slip issue was fixed.

All the broken pumps have been from Z06's. The Z06 has to run the pump on the supercharger drive because of packaging reasons. The tension from the supercharger belt ends up failing the front bearing.

I have not seen a Camaro kit fail yet. Running on the accessory drive is much easier on the pump and bearings.

The allure to the XFP system is that it's extremely simple. Add the pump, injectors, supplied controller, and go. 1,000RWHP+ on DI only.

Companies such as Toohighpsi & Crawford have made port injection a lot more plug & play than it originally was. We are in the middle of 1 job and have 2 more booked for port injection.

[EDFHOBBIES]

Originally Posted by Katech_Mike

We were involved in the development/testing of the original XFP kits. We have installed quite a few of them.

The 1st iteration of the Camaro kit did have belt slip. The brackets were revised and the belt slip issue was fixed.

All the broken pumps have been from Z06's. The Z06 has to run the pump on the supercharger drive because of packaging reasons. The tension from the supercharger belt ends up failing the front bearing.

I have not seen a Camaro kit fail yet. Running on the accessory drive is much easier on the pump and bearings.

The allure to the XFP system is that it's extremely simple. Add the pump, injectors, supplied controller, and go. 1,000RWHP+ on DI only.

Companies such as Toohighpsi & Crawford have made port injection a lot more plug & play than it originally was. We are in the middle of 1 job and have 2 more booked for port injection.

Thanks for answering questions kaytech

Who's ecu are you using to run the port?

Would you say the port route is cheaper?

[Katech_Mike]

Originally Posted by EDFHOBBIES

Thanks for answering questions kaytech

Who's ecu are you using to run the port?

Would you say the port route is cheaper?

We're using the Crawford kit which uses a Holley ECU.

I'm not sure its cheaper.

You need:
Toohighpsi spacer plates/rails
Injectors
Toohighpsi blower lid
Crawford kit
Fittings and lines for the rails

The install is a bit more time consuming as well.

[Dan82679]

Originally Posted by Katech_Mike

We're using the Crawford kit which uses a Holley ECU.

I'm not sure its cheaper.

You need:
Toohighpsi spacer plates/rails
Injectors
Toohighpsi blower lid
Crawford kit
Fittings and lines for the rails

The install is a bit more time consuming as well.

I used the toohighpsi spacers on the stock supercharger so no need for the magnasun lid. I did not need the crawford kit,all I needed was the spacers,injectors and the holley terminator x kit.

[EDFHOBBIES]

Originally Posted by Katech_Mike

We're using the Crawford kit which uses a Holley ECU.

I'm not sure its cheaper.

You need:
Toohighpsi spacer plates/rails
Injectors
Toohighpsi blower lid
Crawford kit
Fittings and lines for the rails

The install is a bit more time consuming as well.

I think you will find that the Elite 950 or up with WBII (2 wideband inputs) will cut the cost by double for the ECU like 2500 bucks That dominator/eliminator kit is an over kill and you don't even need 90% of the inputs. I've seen a few local cars with Holley and you have a lot wires just tied up not being used. It really pays to have a good tuner that usually just makes his own harness.

[EDFHOBBIES]

Originally Posted by Dan82679

I used the toohighpsi spacers on the stock supercharger so no need for the magnasun lid. I did not need the crawford kit,all I needed was the spacers,injectors and the holley terminator x kit.

What was the terminator kit number?