GOLFMK8
GOLFMK7
GOLFMK6
GOLFMKV

Autotech HPFP DIY/Tips

I

ironmb

Banned
Location
Texas
Great write up Diggs, i just purchased my HPFP and LPFP. Was looking into this just yesterday, appreciate the post.
 
P

pieguy

Ready to race!
Location
Bay Area
mk7_bk said:
Nice post. I'm curious, why you did this. I guess you got a bad fuel pump, bought one and fixed it. Not sure all the terminology hpfp lpfp. Assuming our cars with xxx hp require special fuel delivery systems. When would someone want to start to think about replacing the factory, around 400?


Sent from my iPhone using Tapatalk
Click to expand...

Turbos top out depending on fuel options available so if you're stuck with shitty 91, you're turbo is extremely limited (400ish whp) for anything short of a BOSS 600. When you have 93 available, it gets a little better as you can push to 420-450ish whp.

Now, if you have e85 available, which is almost like 105, you're ceiling is significantly higher, but you need more fuel volume of e85 versus conventional gasoline. With an is38 or hybrids, you're limited to basically e30 before fueling becomes an issue. You then need to install a better low pressure fuel pump (LPFP) to get you to e50ish which is noticeably better. Now if you want even more than e50, you need to install either a better High Pressure Fuel Pump (HPFP) or install multi-port fuel injection on top of direct injection.

MPI is better than HPFP (more flow), but much more costly and difficult install wise. It's also really obvious looking when installed which is dangerous to have in a state like California. Better HPFP flows a bit more, but eventually, you're still stuck being capped out by the direct injection fuel injectors. I've seen HPFP+LPFP+hybrid is38 or boss 500 push close to 500 whp and 450ish whp. Everyone please correct me if I'm wrong in some of these numbers. Also, these whp/wtq numbers are super dyno specific and that's why we get into issues where some tuners are running dynos that skew numbers with unrealistic expectations.

Also, Cobb cannot tune MPI right now, only Eurodyne and UM can. LPFP requires special tuning and HPFP does not.

HPFP https://autotech.com/new-products/autotech-high-volume-fuel-pump-gen-3-tsi-tfsi.html
LPFP http://www.precisionraceworks.com/index.php?route=product/product&path=20_61&product_id=67
MPI http://www.precisionraceworks.com/index.php?route=product/product&path=20_61&product_id=87
 
Last edited:
mk7_bk

mk7_bk

Autocross Champion
Location
Philadelphia Area
pieguy said:
Turbos top out depending on fuel options available so if you're stuck with shitty 91, you're turbo is extremely limited (400ish whp) for anything short of a BOSS 600. When you have 93 available, it gets a little better as you can push to 420-450ish whp.



Now, if you have e85 available, which is almost like 105, you're ceiling is significantly higher, but you need more fuel volume of e85 versus conventional gasoline. With an is38 or hybrids, you're limited to basically e30 before fueling becomes an issue. You then need to install a lpfp to get you to e50ish which is noticeably better. Now if you want even more than e50, you need to install either a HPFP or install multi-port fuel injection on top of direct injection.



MPI is better than HPFP (more flow), but much more costly and difficult install wise. It's also really obvious looking when installed which is dangerous to have in a state like California. HPFP flows a bit more, but eventually, you're still stuck being capped out by the direct injection fuel injectors. I've seen HPFP+LPFP+hybrid is38 or boss 500 push close to 500 whp and 450ish whp.
Click to expand...



Wow excellent reply. Still nee to the whole car game but will most likely get into all this within this time next year. Running 93 now. I just looked it up there are some e85 pumps around here. Seems like it would be somewhat of a pain to have to fuel 2 different stations (unless the e85 pump is already mixed.)


Sent from my iPhone using Tapatalk
 
P

pieguy

Ready to race!
Location
Bay Area
mk7_bk said:
Wow excellent reply. Still nee to the whole car game but will most likely get into all this within this time next year. Running 93 now. I just looked it up there are some e85 pumps around here. Seems like it would be somewhat of a pain to have to fuel 2 different stations (unless the e85 pump is already mixed.)


Sent from my iPhone using Tapatalk
Click to expand...

Usually a gas station has both and just has one pump of e85 available. e85 to get to e30ish is like 3.5 gallons of e85 and the rest 93. Even if you're not tuned for e85, adding 2 gallons of the stuff to a tank of 93 nets you a lot of benefits in terms of knock prevention and timing correction, which is what we're discussing in the other thread.

Excellent e85 thread https://www.golfmk7.com/forums/showthread.php?t=14213
 
P

pieguy

Ready to race!
Location
Bay Area
P

pieguy

Ready to race!
Location
Bay Area
Diggs24 said:
$599 for internals? Yikes.
Click to expand...

Yeah wish it was cheaper. You could probably buy a used HPFP and send to APR for a rebuild around the same price.

Really wonder the differences in between Autotech, APR and Mabotech HPFP's. Seems like a lot of he says she says.
 
P

PacDawg

Drag Race Newbie
Location
Gilroy, CA
Nice right-up Digs!! Luckily I knew someone to do the install for me that used to work at a tuner shop and had experience installing HPFP internals. Just had to split cost of tool and traded a set of wheel spacers I wasn't using for his labor.
 
2slowvw

2slowvw

Moderator
Location
VA
Car(s)
2022 Tesla Model 3
I know autotech has been making fuel upgrade internal and parts for a long time now that's why I went with them. I bought mine on eBay when eBay had one of those coupons 20% off any item coupons.
 
Hoon

Hoon

Autocross Champion
Location
Rhode Island
Just finished this job. Diggs covered most of it, but i wanted to share a few additional things/methods.

Autotech says to let the car sit for 20 minutes before starting the job. I didn't have patience for that, so i used rags to cover the fuel lines and got straight to it. Very little fuel came out of the low pressure feed and high pressure output lines, so i thought i was in the clear.

When i cracked the first bolt loose, a JET of fuel shot out of the low pressure inlet. Luckily it hit me in the shoulder and not the face, because i was not wearing glasses at that point.

I used the small harbor freight bearing puller, but because i could not get it directly under the retainer, i chose instead to put it in the spring, as close to the retainer as possible. Because of this, the pump was at a slight angle sticking out of the clamp with the puller.

I made no attempt to use the rest of the puller kit. I sat the clamp on top of the vice, and used a small punch and a 4lb hammer. 4-5 light to moderate whacks and it was out. Whole process took maybe 2 minutes to disassemble the pump, and nothing was damaged. The piston, spring, retainer and bushing could all be reused if needed.

Oh, and i followed Diggs advice and used a 1/2" impact to crack the pump loose. The Autotech tool fits like shit, but it works.

Keep everything very clean and well lubricated throughout the process. On reassembly, i torqued to 60 ft-lbs. Seemed like a bit much, but whatever. I took it apart with the impact so i didn't have a feel for how tight it was initially, but i could tell it definitely had some torque on it.

Car seems to run exactly the same, time to bump up the E content and verify rail pressure.
 
You must log in or register to reply here.
Top