Official Harrop TVS1740 Supercharger Thread

[rotomoto712]

Originally Posted by DrFerry

rotomoto712 In my experience, when going wide open throttle (W.O.T) 6.5psi of boost is delivered at least by 3500 RPM - when the bypass valve has been fully closed by the bypass actuator.

Wow! That would make a massive difference in performance compared to what I've been seeing. What elevation are you at?

[DrFerry]

Originally Posted by rotomoto712

Wow! That would make a massive difference in performance compared to what I've been seeing. What elevation are you at?

My local elevation = 1014ft or 309m and I had no problem getting >6.0psi. Since you are having sustained problems with your Harrop supercharger bypass valve actuator, can you tell us if your kit is new or used?

[rotomoto712]

I bought the kit new last year.

[M.Hagen]

Originally Posted by rotomoto712

Not to thread hi-jack, but out of curiosity, what are some of the Harrop owners at higher altitudes seeing for boost? I've been working with the Harrop guys and BPM on trying to troubleshoot some boost issues i've been having (maxing out at 5.2), and I am curious to what extent altitude affects boost on these. I'm currently at 293M ~960 Ft, but there are many elevation changes where I am, though I don't think any are higher than 2000 ft.

I was seeing between 3.0 and 3.4 PSI at my altitude (nominal 4,300ft).

TVS Superchargers are 'positive displacement' units, which means they pump the same volume of air for every revolution of the engine crankshaft. You will see lower observed manifold pressures at altitude, as the ambient pressure is much lower.

Here is the write-up and logs from my car when it had the Harrop kit installed. I don't have the original images linked anymore, so I apologize for the dead 'Photobucket' links.

https://www.m3post.com/forums/showthread.php?t=1357187

Cheers.

[rotomoto712]

Quick update: I received the new Actuator and ECU from Harrop in the mail yesterday, and after installation, I took it out for a drive and...

...Still not seeing 6.5 psi. However, the boost response is drastically improved. Between 3-4K it quickly shoots up to 5.2 psi and just crests 6.1 psi at redline in third gear. At that same rpm range, it shoots up to 5.5 psi and gets up to about 6.2 psi at redline in fourth gear. The area where I tested is ~1000 Ft in elevation. Seat of pants I can confirm the extra power, as I broke traction in third for the first time.

[DrFerry]

Originally Posted by rotomoto712

Quick update: I received the new Actuator and ECU from Harrop in the mail yesterday, and after installation, I took it out for a drive and...

...Still not seeing 6.5 psi. However, the boost response is drastically improved. Between 3-4K it quickly shoots up to 5.2 psi and just crests 6.1 psi at redline in third gear. At that same rpm range, it shoots up to 5.5 psi and gets up to about 6.2 psi at redline in fourth gear. The area where I tested is ~1000 Ft in elevation. Seat of pants I can confirm the extra power, as I broke traction in third for the first time.

Thanks for the update. Glad you're now seeing >6.0psi at ~1000ft of elevation. Peak boost of 6.2psi at ~1000ft of elevation is about right IMO. See my earlier post about how much boost loss is typical with elevation. Also, I recommend reading through this thread (when time permits) as a learning, since quite a few others have chronicled their experiences debugging low boost, bypass valve ECU issues, bypass valve actuator calibration etc. etc. I'm also glad to know Harrop provided the replacement parts you needed. It might be time for some stickier rear tires...

[rotomoto712]

Originally Posted by DrFerry

Thanks for the update. Glad you're now seeing >6.0psi at ~1000ft of elevation. Peak boost of 6.2psi at ~1000ft of elevation is about right IMO. See my earlier post about how much boost loss is typical with elevation. Also, I recommend reading through this thread (when time permits) as a learning, since quite a few others have chronicled their experiences debugging low boost, bypass valve ECU issues, bypass valve actuator calibration etc. etc. I'm also glad to know Harrop provided the replacement parts you needed. It might be time for some stickier rear tires...

Sticky tires are definitely next up on the to do list. I'm thinking of picking up a set of wheels with Michelin Pilot Sport Cups to use during the summer months.

[RUG8RB8]

Originally Posted by rotomoto712

Out of curiousity how quickly do you hit 6.5 Psi, i.e. at what RPM?

Hello, I finally got around to uploading a short video clip of a 70mph cruise at basically zero boost to WOT stomp. You can see just how fast 6.*** psi hits.

0-6 psi Time

[CamasM3e93]

Originally Posted by RUG8RB8

Hello, I finally got around to uploading a short video clip of a 70mph cruise at basically zero boost to WOT stomp. You can see just how fast 6.*** psi hits.

0-6 psi Time

That looks solid to me and I think you’ve got it as good as you are going to get it. I’m always focused on keeping the car from fishtailing into another lane on similar maneuvers, so curious what mine looks like, lol.

[drwankel]

I really need to get a boost gauge setup in this car...

Anybody got some pictures of their P3 setup? Would love to see how you handled the analog boost sensor, and getting the wiring back into the cabin.

[CamasM3e93]

Originally Posted by drwankel

I really need to get a boost gauge setup in this car...

Anybody got some pictures of their P3 setup? Would love to see how you handled the analog boost sensor, and getting the wiring back into the cabin.

Mine looks like his in the video. Driver door AC vent. 3/8” ID vacuum hose ran from the 1/4” npt port on the passenger side of the Harrop unit connected via a hose barb connector. I ran the hose along the firewall and into the cabin via a small cut on the brake reservoir/booster rubber boot.

[BP709]

Originally Posted by drwankel

I really need to get a boost gauge setup in this car...

Anybody got some pictures of their P3 setup? Would love to see how you handled the analog boost sensor, and getting the wiring back into the cabin.

If I have some time this weekend I’ll take a few things apart to get pictures of how I routed it.

[DRLane]

Originally Posted by drwankel

I really need to get a boost gauge setup in this car...

Anybody got some pictures of their P3 setup? Would love to see how you handled the analog boost sensor, and getting the wiring back into the cabin.

See CamasM3e93 above. It’s literally that simple. Remove the cowl for easier routing near the firewall and use a coat hanger to fish through the access port down by the pedal.

[drwankel]

Exactly the info I needed!

Pictures are still welcome. It will help someone else later.

[RUG8RB8]

I did similar to above, I am on a plane flying to Florida for two weeks or I would send you pics tomorrow. If you still need pics when I get back let me know. I made a tee and have an old fashioned dial gauge as well to verify the P3 is accurate. It is Spot on BTW. I bought a 0-10psi analog so I got better resolution.

[RUG8RB8]

BTW, the female port on the Harrop is NOT 1/8”NPT!!! It is BSP which is slightly different. Australia thing I guess, down under.

[RUG8RB8]

Originally Posted by CamasM3e93

That looks solid to me and I think you’ve got it as good as you are going to get it. I’m always focused on keeping the car from fishtailing into another lane on similar maneuvers, so curious what mine looks like, lol.

I have slightly larger rears 295’s on BBS FI’s, I can’t make them break lose unless everything set to manual and a dead stop WOT. From a roll they are always hooked up. This car just pulls and pulls, but I have a E93 pig, tons of weight.

[CamasM3e93]

Originally Posted by RUG8RB8

BTW, the female port on the Harrop is NOT 1/8”NPT!!! It is BSP which is slightly different. Australia thing I guess, down under.

You might be right, I’ve got an email from BPM support below calling it 1/8” npt. BPMSport can you confirm the size of the pressure sensor port?

[BP709]

Originally Posted by CamasM3e93

You might be right, I’ve got an email from BPM support below calling it 1/8” npt. BPMSport can you confirm the size of the pressure sensor port?

I got the same info from BPM and am running a vibrant 1/8 npt to 90 degree quick connect fitting (vibrant p/n 2665) to a polyurethane hard vacuum line (.156 OD) I compared it to the plug that came out of the Harrop and it was identical diameter/pitch.

[RUG8RB8]

You can cram the incorrect fitting in there but simply call Harrop and ask them, or you can just believe me, because I have called and verified with Harrop. There is a slight difference, but 1/8 NPT will most likely seal even though it is not proper. Never use a plastic PushLok fitting, the heat from engine bay breaks down the plastic and it will leak. If you want a PushLok type, you can order a metal unit from Legris with the proper thread and high temp Viton O-ring.

[drwankel]

This is oddly enough a common problem with Mazda rotary engines. The oil pressure sensor sender is BPT, and many people make the mistake of using a NPT fitting. Why in the world a Japanese manufacturer decided to use BPT I will never know.

I'm somewhat surprised that folks aren't having issues. Using NPT in that oil pressure sender fitting on Mazda Rotary engines typically results in a very slow oil leak and damages the threads on the engine side.

[BP709]

Originally Posted by RUG8RB8

You can cram the incorrect fitting in there but simply call Harrop and ask them, or you can just believe me, because I have called and verified with Harrop. There is a slight difference, but 1/8 NPT will most likely seal even though it is not proper. Never use a plastic PushLok fitting, the heat from engine bay breaks down the plastic and it will leak. If you want a PushLok type, you can order a metal unit from Legris with the proper thread and high temp Viton O-ring.

Just went off the info from BPM. Nothing was crammed in by any means. It threaded in smooth by hand and has no leaks after nearly two years but I’ll definitely be looking into a metal unit from Legris as you suggested. Appreciate the info.