Author Topic: HPFP or in tank pump... whats the real limiting fuel factor? (Read 123658 times)

snaponbob · « **Reply #125 on:** March 06, 2012, 01:57:50 PM »

Joshmass, by "supporting pieces in place", are you referring to bigger turbo and hotter cams, or stock hardware?

SKY888 · « **Reply #126 on:** March 06, 2012, 02:34:24 PM »

Quote from: joshmass on March 06, 2012, 12:43:50 PM

1. HPT will work in conjunction with Trifecta as long as it's a "write calibration only". Vince's software is written to the ECU in a different manner than HPT so both can work simultaneously. However, if you do a "write entire" with HPT it will wipe out the Trifecta tune.

This is true, especially last year when HPT hasnt cracked the fuel pressure tables and such.....and tuners have been overlapping the trifecta tune to HPT tune....so they get to increase the fuel pressure.

But HPT can't adjust any of the trifecta tunes......and vice versa. Totally different platforms.

3. The appropriate Bosch HPFP upgrade (above 200 Bar) would appear to be the HDP-5-FCV-HP but it requires plumbing in a return fuel line and an in-line pressure regulation valve. You also need to talk to Bosch regarding the maximum fuel pressure you want to have and they will advise you on the shape/size/number of cam lobes required. I'm not sure what Comp would charge for a one-off set of cams but they make ZZP's cams. Therefore it's not impossible - just maybe cost prohibitive.

I dont know who will be the person who will spend a TONS of money to do this route.
bosch pump.....plumbing/regulation valve........and one-off comp cam? Lots of R&D on what cam will work properly on the lnf engine.

5. I thought that Werks had solved the low pressure pump issue with their upgrade? They claim it can support up to 700hp but I haven't seen any real world evidence yet that shows it.

The DW300 should work.
But none so far had tried it.

There's a kappa guy, who installed the 500hp in-tank pump.......and dont have any more issues with his set-up.

6. 450whp/wtq can be achieved with the stock fuel system (with a 4K-5K wide torque curve). You just need the other supporting pieces in place.

With regular gas, yes very possible. But using E85, stock system will not be able to support adding about 30% more fuel needed.

joshmass · « **Reply #127 on:** March 06, 2012, 02:36:07 PM »

Quote from: snaponbob on March 06, 2012, 01:57:50 PM

Joshmass, by "supporting pieces in place", are you referring to bigger turbo and hotter cams, or stock hardware?

There are a few ways of going about it, but all would require some upgraded components. I'm not sure what the OP's goals are or how he wants to go about attaining them. There's so many variables to take into consideration but coming up with a plan beforehand would help narrow it down. I think the fuel system issue is a moot point for most. Not everyone is chasing 700whp like Antonio.

Your situation is different of course, but judging by information that's come to light about using E85 with these motors, IMO you're wasting your time chasing the fueling issue. GM has already shown that this LNF design was not optimized for E85 and has taken the steps to improve it in the next version of the Ecotec. If you really want to run E85, wait a bit for those parts to release in the aftermarket. That includes HPFP, pistons, injectors and injector seals. Otherwise you're fighting too many battles to get it to work.

Don't get me wrong though, I think an ethanol fuel source is going to be the way to go with these motors eventually. There are so many upsides to it and fuel economy appears to be the only major downside.

joshmass · « **Reply #128 on:** March 06, 2012, 02:39:32 PM »

Quote from: SKY888 on March 06, 2012, 02:34:24 PM

6. 450whp/wtq can be achieved with the stock fuel system (with a 4K-5K wide torque curve). You just need the other supporting pieces in place.

With regular gas, yes very possible. But using E85, stock system will not be able to support adding about 30% more fuel needed.

Exactly Antonio. But more to the point, power is power. If you can achieve the target using pump gas than what's the argument to use E85?

SKY888 · « **Reply #129 on:** March 06, 2012, 02:40:59 PM »

Bob is ethanol fanatic right now.....due to the increase in TQ!

joshmass · « **Reply #130 on:** March 06, 2012, 02:43:56 PM »

Quote from: SKY888 on March 06, 2012, 02:40:59 PM

Bob is ethanol fanatic right now.....due to the increase in TQ!

I understand but I don't lurk here enough to know what his current numbers are or what he wants to make for power. Isn't he restricted in what he can do to the engine by the sanctioning body?

SKY888 · « **Reply #131 on:** March 06, 2012, 02:46:29 PM »

yeah, Bob is restricted to basic bolt-ons.

no cams.....no nothing.....

E blend is the only allowed

snaponbob · « **Reply #132 on:** March 06, 2012, 03:46:51 PM »

Quote from: SKY888 on March 06, 2012, 02:46:29 PM

yeah, Bob is restricted to basic bolt-ons.

no cams.....no nothing.....

E blend is the only allowed

E60 helped, but is not a cure. Still playing.

BTW, you can have a fire engine pumping fuel to the engine fuel pump, and if IT can't supply enough, than not enough fuel will get in the engine.

kennysabarese · « **Reply #133 on:** March 06, 2012, 03:53:02 PM »

I thought that liquids behave the same as gas, that if you increase the pressure in the line feeding a pump, that the pressure on the other end of the pump will increase. Just like a compound turbo setup.

miller11386 · « **Reply #134 on:** March 06, 2012, 03:58:13 PM »

Has anyone tried mixing something like race gas with pure E? just curious what octane your are running on your E blend.

I would be interested how close you could get to 120 octane with VP C16 & E98 mix. (granted it would be ~$30 a gallon)

Not sure what your E60 blend is a mixture of, but i know the E47 is mixing E85 and 93 oct at 50/50 ratio. Could be interesting to get E98 and C16 together.

joshmass · « **Reply #135 on:** March 06, 2012, 04:23:44 PM »

Quote from: snaponbob on March 06, 2012, 03:46:51 PM

BTW, you can have a fire engine pumping fuel to the engine fuel pump, and if IT can't supply enough, than not enough fuel will get in the engine.

I agree. If the HPFP is maxed out at 2900 psi, what kind of effect would trying to feed it more fuel have? I would think that adding volume wouldn't increase pressure at that point because the pump is at its physical limits. The only modifications I can think of at that point would be to modify the cam lobes that control the pump (20% volume increase) as well as increasing the fuel injection window in the tune (limited to roughly 6ms in stratified charge). I've seen other HPFP's that can be altered in other ways (spring/plunger) but those units aren't sealed like ours.

snaponbob · « **Reply #136 on:** March 06, 2012, 04:26:34 PM »

Quote from: Kenny on March 06, 2012, 03:53:02 PM

I thought that liquids behave the same as gas, that if you increase the pressure in the line feeding a pump, that the pressure on the other end of the pump will increase. Just like a compound turbo setup.

If the injector pump can't generate enough flow, it does not matter what is feeding IT. Put another way, if the tank pump was running at 4000psi, and the pump that IT supplies can only create 3000psi, than the second pump becomes a restriction !!

joshmass · « **Reply #137 on:** March 06, 2012, 04:30:00 PM »

I forgot to add that ZZP is using a 5th injector setup to add fuel as well.

SKY888 · « **Reply #138 on:** March 06, 2012, 05:27:40 PM »

Quote from: joshmass on March 06, 2012, 04:30:00 PM

I forgot to add that ZZP is using a 5th injector setup to add fuel as well.

I dont trust the 5th injector set-up though. That's my opinion.
You won't even know if each cylinder is getting equal amounts of fuel.
AFR looks good.........but all of a sudden the engine goes kabooo, because one cylinder wasn't getting proper fuel compared to others.

SKY888 · « **Reply #139 on:** March 06, 2012, 05:30:52 PM »

Quote from: miller11386 on March 06, 2012, 03:58:13 PM

Has anyone tried mixing something like race gas with pure E? just curious what octane your are running on your E blend.

I would be interested how close you could get to 120 octane with VP C16 & E98 mix. (granted it would be ~$30 a gallon)

Not sure what your E60 blend is a mixture of, but i know the E47 is mixing E85 and 93 oct at 50/50 ratio. Could be interesting to get E98 and C16 together.

what will you be trying to achieve w/ a 120 octane + E98 though?

why spend money on a race gas.......if you can just go w/ ethanol blend, and get the same or probably even more whp/tq with waaay less money?

SKY888 · « **Reply #140 on:** March 06, 2012, 05:35:24 PM »

Quote from: snaponbob on March 06, 2012, 04:26:34 PM

If the injector pump can't generate enough flow, it does not matter what is feeding IT. Put another way, if the tank pump was running at 4000psi, and the pump that IT supplies can only create 3000psi, than the second pump becomes a restriction !!

I agree with Bob!

Kenny, with the compound set-up, there's no restriction since the small turbo , is just re-compressing an already compressed air.

With liquids, you can't re-compress it, that's why the HPFP's physical limitation, will still be the restriction.

miller11386 · « **Reply #141 on:** March 06, 2012, 05:41:02 PM »

total octane would be higher i think... IE:

E85 & 93 octane (at the same 50/50 blend) would net somewhere in the area of 97 octane.

C16 blended with E98 (at the same 50/50 blend) would net somewhere in the area of 117 octane.

So in essence if you get E98 (octane of 120) and mix in your own 115 octane race fuel, you would get a higher net octane...right?

SKY888 · « **Reply #142 on:** March 06, 2012, 05:42:45 PM »

ok

so why dont you just run pure 120 octane race gas, if you're just going for high octane?

why mixed it with ethanol....to lower it down to 115 octane?

miller11386 · « **Reply #143 on:** March 06, 2012, 05:50:49 PM »

Quote from: SKY888 on March 06, 2012, 05:42:45 PM

ok

so why dont you just run pure 120 octane race gas, if you're just going for high octane?

why mixed it with ethanol....to lower it down to 115 octane?

E could help quiet the potential for knock? Idk because I would never afford pure race fuel ... E98 is not completely horrible, but $5 a gallon means its not going to be an every day thing. Esp when i would have a limited supply

SKY888 · « **Reply #144 on:** March 06, 2012, 05:59:45 PM »

both race gas and ethanol has their own characteristics to fight knock.

I like ethanol because it burns cooler to prevent detonation.

On a stock turbo lnf, you will gain very little power by switching to higher octane, whereas E85 is worth significant gains. If you are running a larger turbo that allows you to run a lot more boost, then you can start seeing some gains from race gas over 93 octane, but E85 will still make more power

If you were running 30psi boost or more, the gains would increase quickly because you would have to run the 93 tune very conservative, but not the Race gas tune. E85 on the other hand will result in gains at any boost level or on any turbo.

What makes running Race gas different on the LNF than on many other turbo motors- Running Race Gas typically makes more power because you can add more boost, add timing, and lean out the mixture. However, with supporting mods on the LNF, you can already max the stock turbo and run a 12.8:1 afr on 93 octane. This takes away two of the three advantages that you can normally utilize. Spark timing is also different on the LNF than on most other motors. The design of the piston makes injection timing and placement critical which may require some adjustments to get the most out of slower burning, higher octane racing fuel. Yes, you can get gains from Race gas, but don't expect more than a few hp at best. On the LNF, gains from Ethanol or methanol are mostly from the increase in energy availble from the overall amount of fuel being burned.

Kelu · « **Reply #145 on:** March 06, 2012, 07:17:08 PM »

Quote from: SKY888 on March 06, 2012, 05:59:45 PM

On the LNF, gains from Ethanol or methanol are mostly from the increase in energy availble from the overall amount of fuel being burned.

Huh? Ethanol energy from burning is LESS than the one from gas, that's why you have to pour 30% more when running on E85 to match the power obtained from gas. Has nothing to do with LNF in particular

The gains from fuel comes from:
- timing (KR resistance) - octane
- leaner AFR - still octane
- % of O2 from the fuel - Q16 has 30% O2

Ethanol burning "colder" means less energy so no gains from here

Q: how many of you will drive the car daily with over 450whp? (joshmass has a pretty good point imho)
You afford many thousands in engine mods and you don't want to spend 100$/race on race fuel?

miller11386 · « **Reply #146 on:** March 06, 2012, 08:01:45 PM »

Reguardless of cost, its just not practical to tune your car solely on race fuel whether its E98 or C16. For example it would be very hard to get to SMMM or DDM with just one tank of gas!

I want to drive mine at ~550-600whp on 93 octane every day. With a high rpm to spool It should not be too terribly un-streetable

Kelu · « **Reply #147 on:** March 06, 2012, 08:07:42 PM »

550-600whp and boost at high rpms on our cars = un-streetable 100%

miller11386 · « **Reply #148 on:** March 06, 2012, 08:27:38 PM »

Maybe in Romania, but we drive those on the road all the time here. See the following vid. Side note, fresh E85 in the tank, and the car cracked 805whp on a mustang today.

STMs Project RS Street Car, Round 2 of Dynos!

We also have UR lambos pushing 1500hp, Vettes/Vipers pushing 1200hp etc... all "street legal" cars

kennysabarese · « **Reply #149 on:** March 06, 2012, 08:28:06 PM »

Quote from: SKY888 on March 06, 2012, 05:27:40 PM

I dont trust the 5th injector set-up though. That's my opinion.
You won't even know if each cylinder is getting equal amounts of fuel.
AFR looks good.........but all of a sudden the engine goes kabooo, because one cylinder wasn't getting proper fuel compared to others.

Carbeurators and Throttle Body Injection work perfectly fine under this same principle, so I don't think anyone should be concerned.

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Author Topic: HPFP or in tank pump... whats the real limiting fuel factor? (Read 123658 times)