Jaxian

By fuel system I mean from the pump to the injectors and the computer also. From my signature at the bottom you can see what I have, the only change will be swapping a D1 for my P600b.

I know that injector size can be figured out pretty easily by just crunching the numbers and the same for pump size. More the issue is configuration, I was told the stock computer gives up at 500hp and the stock fuel system at around 550hp.

1. Do I use the stock fuel line now as the new return line.

2. Do I have to plumb a new pickup line into the tank in the new larger fuel line size. I have no clue how hard this is to do or if there is a kit that has a drop in section already done, which would be nice. I assume this would go through the existing removable section that has all the lines going through it.

3. Do I need to machine out the stock fuel rails or is there an aftermarket alternative. I have seen a number for hondas and fords, but not TPI engines.

4. Would the crossover need to be replaced with a larger steel braided unit. Boy I hope someone makes a pre done hi flow fuel rail kit.

5. Should I try to use some sort of in tank set up or just use one of the large inline pumps and filters available and mount it under the car. I am not sure any in tank ones can feed a D1 intercooled 406. Any recommendations on brand would be cool.

6. The Accel DFI Gen 7 seems to be a popular aftermarket computer, although at $1420 its painfully expensive. And the broadband 02 option adds another grand. Just how necessary is this? Does it require a laptop to run or is it stand alone?

7. Any recommendations as to pump and line size to feed this combo?

I am sure there are more things I am forgetting to ask but this should get me started. This part of the buildup has been making me apprehensive for quite a while. Because of all the variables and the knowledge that with FI engines the correct combination is the key to everything and having a badly mismatched component can mess up the whole system. Any recommendations and advice is most appreciated and I can start trying to overcome the fuel system monster I have been fearing for so long. Thanks much.

vvv90

You can use your stock computers and fuel lines for your HP output. You'll just need to let the tuner who burns your chip know your mods.

From what I've been told, your stock lines can support up to 700HP

If this was necessary for you, which I don't think it is, the hardcore guys run sump the gas tank, but this is a lot of work.

Vette92 can chime in to this. What he has is 2 Walbro GSS340 255lph pumps. One of them is using the stock lines, then he ran new lines for the other one and got a feed line welded onto the other side of the fuel rail....er. something. :confused: ask him. You can checkout http://www.TPIS.com I know they have an aftermarket miniram setup, but I'm not sure about L98 stuff.

Not if you do what I stated above.

Walbro GSS340 with the "boostapump" will support up to 700HP. http://www.racetronix.com contact tech support there if you have any questions. They're very knowledgable.

It's not absolutely necessary, but from what I know, I definitely want one and it's indespensible for proper tuning. With that system your car will run right ALL the time and have full power without detonation. If you have the money GO FOR IT! Especially considering you have a highly custom setup, I think you're just going to set yourself up for alot of frustration if you don't get a good aftermarket setup like a DFI. burning chips will get old fast. REGARDLESS of what you do, go to http://www.innovatemotorsports.com and get their wideband O2 meter. It's only $350 which is incredibly cheap. I wouldn't even turn the key on that car without it. You'd better get a copy of datamaster too to keep on eye on the motor http://www.ttspowersystems.com.

All you'll need is a walbro GSS340 w/ "boost-a-pump" with stock lines. Should take no more than an hour to install. OH, don't forget a good AFPR too. :thumbs:

It's actually not a monster at all. That's the beauty of fuel injection. You have more pressure than a carb setup which equals more fuel delivery on standard 3/8" lines.

Jaxian

Awesome response, thanks very much. Now I have some direction as to were to start. Was getting worried that no one would reply to it, heh. Thanks for biting the bullet and helping me out! :cheers:

SPD DMN

Here are some pictures of my fuel mods under the hood. I simply ran a new 6an line from the tank and tied it into the system as shown.

Pic 1
Pic 2
Pic 3

Maybe it helps a little. You can also wire it to where the second pump is only on under a certain amount of boost. I just let mine both run all the time.


[edit] The image tags are screwing up - changed to url links.


[Modified by Vette92, 1:14 PM 10/14/2003]

krivera

nice!

mn_vette

So basically you ran another feed to the pressure test port on the fuel rails and everything is good??
Does the stock return line handle everything ok??
How did you plum the sending unit on the tank??
Were there any other mods to the fuel rails?
Are you still running the stock FPR with a spring adjustment on it?


[Modified by mn_vette, 10:23 PM 10/14/2003]


[Modified by mn_vette, 10:26 PM 10/14/2003]

SPD DMN

No, I drilled and welded a new 6AN bung into the drivers side fuel rail. I did not use the 4an test port. The stock return line handles to 3/8 stock feed line plus the new 6AN line feed just fine. As for the pump and pickup, I band clamped the new pump to the stock pump to where they both feed from the stock in tank baffle.

Chris

Jaxian

Cool this info is helping alot as to what I can do to get the fuel system up to snuff. Sounds like the Racetronix GSS340M kit would be a good place to start but their website is a little short on info. It doesn't say how many Gallons Per Hour the pump moves or what type of HP level it can support. I searched on their webpage for a phone number or some way to contact them but can't find anything. They show the kits as being factory direct purchasable items, show the prices and the shipping, and that they take credit cards but they don't have a number to put in an order or ask questions. Odd. Maybe I am just missing it somewhere on the page. I guess I could call and talk to one of their distributors but I figure why bring in a middleman for a part the factory sells and should have the most reliable info on. The webpage doesn't even mention the Boost-a-pump thing, not sure what that is.

I have been talking to some people and keep getting different opinons on how much horsepower the stock fuel lines and rails can take. Numbers seem to be hitting from a low of 550 to upwards of 700. If its only 550 then my motor with the D1 will be in trouble at higher boost levels. So I am still trying to figure at what horsepower level I need to step up to bigger lines or rails. Actually I guess they might have different flow levels, like the rails can take 700hp stock, but the lines or pickup only 550hp. I will keep watching the boards and try to see the setups people with those power levels have that they have made work for their motors.

Thanks again for the help, it is giving me a lot of directions now to dig up some info and get this thing done right. I have like 15k into the motor without the blower and don't want to melt it.

SPD DMN

The GSS340 and GSS307 pumps are both 255lph flow pumps. The difference is that the 340 pump flows fuel better than the 307 at higher fuel pressures (55+ psi). I am running 2 GSS340 pumps in mine.

FWIW, the stock 3/8" lines could probably feed up to 700 hp. The 550 hp limit is with the stock fuel pump. I just went with the extra pump because I wanted more of a dedicated pump to run the nitrous with. I tied it to the fuel rail as a safety measure and to take advantage of the stock return line and fuel pressure regulator.

I imitated my buddies 383 blower motor setup that was using pretty close to this same setup but he was using two stock pumps.

Chris

vvv90

Do a search on the left for a user called "racetronix" he's the tech support guy and usually adds to the topics with great help. They're a top notch company. I don't know about info on the site but I've ordered from them direct. There should be an email to send to to also get more info on the "boost-a-pump"

As for the fuel rails, I don't know about the L98's, try contacting someone at http://www.tpis.com and pose the question to them.

:cheers:

mn_vette

Ok, I'm just thinking about this becuase I could probably sit down and do it tonight with the parts that I have.

I've got one Walbro in there already, what about taking my stock pump that I have left over and running that through a 4an line all the way to the fuel pressure test port. The big key being no fuel rail modifications.

If the stock pump supports 4-500 and the walbro supports 600 that should be an easy 900 hp fuel system. I'd leave the second fuel pump on a relay hooked to the nitrous arming switch.

Does this sound right or am I missing something. Given that both pumps would be at the same fuel pressure I would think this would be ok.


[Modified by mn_vette, 10:36 PM 10/15/2003]

SPD DMN

The only problem that I see with it is that both pumps are feeding into the same fuel log and the second log is only being fed by the 3/8" crossover line at the back of the '92-93 fuel rails. I would think it would only benefit if the crossover was increased in size, but it may help overall if the first pump simply can not keep up with fuel demand. Not sure how much fuel you can flow through a 4an line.

Where are you getting the fuel for the nitrous, or are you running a dry system? I had an alterior motive in runnng the 6AN line as I did not trust the test port to flow enough fuel to feed the nitrous.

mn_vette

I thought that the incomming line made a "T" and split to both fuel rails and there was a crossover for the return just aft of it. If my fuel pressure regulator is on the pass side fuel rail and so is the fuel pressure test port it would leave me to believe that the extra fuel would not go near the crossover.


Here's the kicker, the fuel for the nitrous is run directly off of the fuel pressure test port. There is a 1ft line that goes into the fuel solenoid and just before that I would put a "T" junction in and run the fuel into that. So I'm assuming some/most of the fuel would flow directly out of the line into the solenoid without even entering the fuel rail.

:confused: The big question I have is how do you plumb the second line through the top of the sending unit?? :confused: And how do you hook the wires to the fuel pump??





[Modified by mn_vette, 11:15 PM 10/15/2003]

Racetronix

You should not mix two different pumps.
HP support is not cumulative for parallel pumps as pressure drop across the feedline increases with the volume demands.
A single in-tank GSS340M + Racetronix harness is good for 550RWHP+ (this is with a safety margin. We have seen well over 600RWHP).
If you order the series II harness with PnP pump booster interface (add BAP / MSD) it can support upwards of 700RWHP assuming normal operating pressures with properly sized injectors.
L98 rails have a balancing problem so a line should be added between the L & R rails.
For setups of this nature we recommend you contact More Performance as they stock the series II kits and can advise you on its high HP application.

Jack :cool:
Racetronix

mn_vette

Hey Jack, I've got a 396 putting ~450HP and I just ordered the jets for my 250HP shot-o-noz. That's about 700hp give or take, but to be on the safe side I'll stick with the dual pumps. And when/if I add the supercharger next year, I won't have to change it again(I did order a second walbor to match). Atleast not in the tank. Thanks for the info. :seeya


Jaxian, dude, sorry about hijacking the post. You got me thinking and excited. If I'm running 12.4 on motor, that 250 shot should get me very close to 10's. I just have everything overnighted and it should be ready for the track on sat. So we'll see.


[Modified by mn_vette, 9:26 PM 10/16/2003]

steve40th

Is the GSS340 a Bolt in to the 93 Vette tank? Also, what is th ePnP booster with BAP/MSD?

SPD DMN

Yes Steve, the GSS340 is a direct replacement for stock. The way I got two of them in there is with a simple band clamp that holds the new pump to the stock one. They both pull from the baffle inside the tank.

I do not know what that other part you mention is. I think it ups the voltage to the pump causing it to flow more, but I am not sure.

Bruce

Is the GSS340 a Bolt in to the 93 Vette tank? Also, what is th ePnP booster with BAP/MSD?

all 255lph intank pumps are a direct replacement. The PnP ia plug N Play wiring harness. BAP= Boost A pump. Either kene Bell BAP od MSD BAP


Bruce

POLOVETTE 94

Jack,
You have mail
Darren