I was just browsing HRCs turbosystem website and I noticed they brag about their fuel system. What makes their fuel system so 'impressive'? How is it different from STAR's turbo kit (with adjustable FPR) ?

As well, how old is the T3/T4 turbo design? The mitsu super16g is about a decade old...



l e o n

I would say very little IF, IF, IF you get an adjustable model for the STAR system and place the FPR in the engine bay. That's the ket difference though: HRC has a short vacuum line to the stand-alone adjustable FPR, While STAR has a long vacuum line(to the back of the car) to a non-adjustable FPR that supplements the stock FPR.

Components are similar though.

HRC: Weldon in-line fuel pump, Bell Adjustable FPR, service fuel fitting(96+), Aluminum and Soft Fuel lines, check valve, fuel mapper

STAR: Walbro in-tank fuel pump, Vortech non-adjustable FPR, Metal vacuum line, check valves

Each fuel system has good aspects to it. I would pull different qualities from each fuel system if I were to design my own from scratch. From HRC, I you take most of their design including location of the adjustaBLE FPR save for the in-line fuel pump. From STAR, I like their use of an in-tank high pressure quality fuel pump.

Combining the two of these together would garner you the best of both worlds.


Jason
98' Eagle Talon ESi-T
Mitsu Super 16g Turbo(HRC)


http://springfielddsm.homestead.com/JasonsPics.html

>I would say very little IF,
>IF, IF you get an
>adjustable model for the STAR
>system and place the FPR
>in the engine bay.

Yup, that's what I did for my STAR KIT. However, I seem to be missing some parts....damn it

>That's the ket difference though:
> HRC has a short
>vacuum line to the stand-alone
>adjustable FPR, While STAR has
>a long vacuum line(to the
>back of the car) to
>a non-adjustable FPR that supplements
>the stock FPR.
>

Well, with the 1995 cars, you are forced to put the FPR in the engine bay. =)


>Components are similar though.
>
>HRC: Weldon in-line fuel pump, Bell
>Adjustable FPR, service fuel fitting(96+),
>Aluminum and Soft Fuel lines,
>check valve, fuel mapper
>
>STAR: Walbro in-tank fuel pump, Vortech
>non-adjustable FPR, Metal vacuum line,
>check valves
>

What do these check valves look like? Plus, what's the HRC fuel mapper do?

hmmmm

The check valve doesn't look particularly special. All it does is allow air to flow one way but not the other. So basically, it's about a one inch wide round plastic piece with smaller nipples on both sides. On one side a vacuum line would be connected. On the other side, just open to the atmosphere. This would allow excess boost to escape after the FPR is done with the signal and then close during vacuum to not allow air to come in the other way.

As far as the fuel mapper, it serves the same function as the VC1. Also, sounds somewhat similar to a check valve except it's electronic in nature and not mechanical like a check valve. (It's also known as a "pentantiometer" in the engineering community) Instead of bleeding off excess air, it bleeds off excess electricity that acts as a message sender from the map sensor to ecu. The excess message would come when the map sensor reads anything over 0 hg/in. of vacuum or just under 1 psi of boost. TO equate that in an electical format, thats anthing over 4.7-5.0 volts. That's a range where the ecu does NOT want to venture since at that air reading/voltage, the ecu will be delivering maximum fuel potential. It of course doesn't realize that when a vc1/fuel mapper is applied. Our cars with an upgraded fuel pump however are capable of delivering enough fuel to serve a stoichiometric ratio to around 10 psi's of boost. Just goes to show you how much extra they build into cars nowadays.


Jason
98' Eagle Talon ESi-T
Mitsu Super 16g Turbo(HRC)


http://springfielddsm.homestead.com/JasonsPics.html

>The check valve doesn't look particularly
>special. All it does
>is allow air to flow
>one way but not the
>other. So basically, it's
>about a one inch wide
>round plastic piece with smaller
>nipples on both sides.
>On one side a vacuum
>line would be connected.
>On the other side, just
>open to the atmosphere.
>This would allow excess boost
>to escape after the FPR
>is done with the signal
>and then close during vacuum
>to not allow air to
>come in the other way.
>

Where is this check valve exactly hooked up too? In between the vacuum line to the FPR? Where can I get a check valve cause I seem to be missing one...
However, is this check valve essential?

>
>As far as the fuel mapper,
>it serves the same function
>as the VC1. Also,

But with 1995 OBD1 cars they don't need the fuel mapper/VC1, right? I just wanna check if the HRC kit for the 1995 cars have one or not.

Shouldn't be essential... Except for things that contain diaphrams like the EGR valve and perhaps the stock FPR... Don't quote me on that, however, since i don't know about the stock FPR at all. I have heard of people rupturing thier EGR diaphrams because of unchecked boost, tho. As far as a fuel mapper for the 95's, i'm pretty sure HRC doesn't include one... Since they know we don't need them. :-)

-DarkOne
I'm so bad, i should be in detention.

In fact, HRC does include one.

I wouldn't say it's an essential piece, but what it does is provide an out for the boost after it goes through the adjustable FPR. (The extra signal sending air/boost needs an out.) So here's where the check valve sits: The vacuum line runs from the intake plenum to the adjustable FPR, and then the FPR has a vacuum line that runs off of it to the check valve. If you didn't have a check valve here, it would be like a small vacuum leak in your system.

Now, I'm not sure if the Vortech requires one, but a HRC adjustable FPR (Bell) certainly does.


Jason
98' Eagle Talon ESi-T
Mitsu Super 16g Turbo(HRC)


http://springfielddsm.homestead.com/JasonsPics.html

LAST EDITED ON 04-Jan-01 AT 00:55 AM (PST)

Hmm, any picture of the bell fpr? I wanna compare how it is hooked up to mine.

My vortech SFMU has a bleed screw that allows me to adjust something (along with a boost screw)...Could that be the "check valve?"

Also, does the HRC instructions say to disconnect the vacuum from the stock FPR? Any check valve to hook with the FPR?


l e o n

Just wished to make a clarification on the fuel pump differences between our in-line pump and the in-tank pumps used by other turbosystems.

I have noticed a tendency for board members to recommend the in-tank type over our in-line model. This may prove to be bad advice to give, as the following must be considered:

The commonly available pumps that install in-tank (replacing the stock pump) are by Walbro, and rated at 255 LPH. However, an important distinction: this volume is measured at 45 PSI delivery pressure. As pressure is increased, the volume the pump can supply falls off dramatically. This pump was never intended to provide the 100 PSI these systems need, and I believe it is dangerously close to maximum output, if not beyond, at 100 PSI.

When upgrading the factory turbo car, we steer away from the Walbros and use a Nippondenso pump (much more reliable, if a bit more expensive). Why not use the same pump for our RS/GS turbosystems? It has an internal relief valve that will not allow pressures above 85 PSI. Of course, as the factory turbo uses a 1:1 FPR, it would only need to provide 65 PSI pressure @ 20 PSI boost (45 PSI base +20). So it works well in the factory turbo cars with their lower fuel pressures.

As the above alternatives were therefore deemed inadequate for our turbosystems, we arrived at our current in-line setup. Our ACCEL pump is roughly twice the size of any in-tank pump. We also include relay/wiring/instructions to bring 12V to the pump from the battery, so as not to overload the factory wiring harness, as it was never meant for the current draw any of these pumps can pull at 100+PSI.

The combination of the stock in-tank pump feeding our correctly wired ACCEL pump has been proven safe up to the 475 HP our RS develops: read that carefully, that is PROVEN, not just theorized or "potential" conjectures. It has been an excellent, dependable setup. It is standard equipment in our Stage I and II systems, and is therefore also intentionally designed to allow higher Stages to be employed later without having to again re-engineer the fuel system. The extra capacity it gives Stage I and II owners is a plus, as it will be able to overcome some deficiencies such as a restricted filter or tank sock, low voltage, or anything else that can reduce pump output. Pumps that are already running at full output (like the in-tank) offer no such reserve potential, and results can be devastating if everything is not "just right" (which happens more often than you may think!).

Sure, it's a bit more expensive, and a little harder to install. But what is a ruined engine, or simply reduced performance, worth? We feel our approach is good insurance for our customers. Period. It's another way we have strived to make our systems as trouble-free over the long term as possible.

I am gonna go beat the ol' RS up on a drive home in 18 degree weather now. I love winter: the additional HP from the cold, dense air is addictive! Hope I find someone to play with tonite!

Wow...

Now I'm interested in knowing more about this in-line fuel pump. Can someone tell me where is it installed?

Also, what if ppl rewire the in-tank fuel pump replacement straight to the battery? Will that help it somewhat?



l e o n

I'm glad to see that HRC is posting on the board again. I was afraid that we had seen the end of their helpful and quite informative posts on the board.
After close to eight months trying to decide between the HRC stage 1 and the Star stage 2, I finally decided to go with the HRC kit. The FMIC and 280ish hp offered by the Star kit (plus the group buy price of $2600) is very tempting, but the quality and documented, relentless testing by Hahn is the deciding factor. I can live with the 60-70 less horsepower (for now) knowing that I have technical support right behind me in case something goes wrong. Now all I need to do is get the money! }> (it sucks being in college)
It would be nice if there were some sort of financial aid that came with the kits :P


Jeff --->soon to be turbo when enough $$ comes in.

http://gs.dsmpower.com

Its nice to see HRC actually posting, though I doubt Ill get an answer to this question. I bought the first production kit, I have never been able to get it past 100 psi of fuel pressure, though the instructions recommend 105-115 for 8psi (its been awhile since I looked at the directions, but I know im right in the ball park)and a tech I spoke to mentioned that HRC revised there fuel system (said I had the 1st gen fuel system setup) I would like to know what is the difference between the original fuel setup and the one currently shipping. I've tried emailing this question to HRC, but got no reply. I've toasted one piston cause of leaning out, I'd buy the better fuel setup if I knew what it was.

I was planning on using a Walboro in-tank fuel pump and keeping the inline in place as well, any pros-cons in doing this, anybody??

Our ACCEL inline pump mounts adjacent to the fuel filter, and includes mounting bracket, plumbing components, and relay/wiring for full 12V operation.

Question: Will rewiring the system to bring a full 12V to the intank (Walbro) pump help? Most certainly, but the pump is still straining to maintain that high pressure even with ample voltage. The best advice I can give for the intank pump guys is to monitor fuel pressure regularly to be immediately aware of any deficiencies under high boost. Consider a permanently mounted gauge. HRC owners need not be as concerned, although occasionally using the gauge we provide with the kit is a good idea, especially if you run at 9 or 10 PSI boost. Inexpensive AirFuel meters, although not real accurate in the desired WOT mixture range of about 12:1, can also be a good indicator if a problem should arise.

Nemezis: The fuel system you have is correct, and not in need of updating. Adding a Walbro intank pump should not be neccesary. Should you have trouble achieving full pressure under boost when you run the car again, please contact our Tech Support line (630-801-9065). We will review your setup and recommend diagnostic procedures to find and correct any problem you may have.

>Our ACCEL inline pump mounts adjacent
>to the fuel filter, and
>includes mounting bracket, plumbing components,
>and relay/wiring for full 12V
>operation.

Isn't the fuel filter near the front of the car? That would mean having a long line going back to the tank?


>I can give for the
>intank pump guys is to
>monitor fuel pressure regularly to
>be immediately aware of any
>deficiencies under high boost. Consider
>a permanently mounted gauge. HRC

I'm doing this, but I noticed that it's quite hard to find a fuel pressure guage that reads over 100 psi!


l e o n

The fuel filter is in the back of the car, passenger side, right by the fuel tank. There is a long return line but its because you have to run a line from the FPR in the engine compartment back to the tank on HRC systems.
And yeah, finding a fuel pressure gauge over 100psi is impossible, maybe there is an aviation gauge that can ;-)

It's the the filter that's attached to the pump that's in the tank, right?


l e o n

It's the the filter that's attached to the pump that's in the tank, right?


l e o n

Not sure exactly where (need to replace mine soon) but it's int he engine bay, drivers side (i think) close to those relays on the firewall.

-DarkOne
I'm so bad, i should be in detention.

Man, it's cramped there!!!!


Yeah I gotta replace mine too...


l e o n