PERRIN Turbo Inlet Hose Evolution

The PERRIN turbo inlet hose has been one of our best selling, long standing products for many years. Since the beginning we have made our part different than the rest.  It wasn't a silicone copy of the OEM part, it wasn't a hard pipe, and it wasn't a 4 hour install.  From the beginning we had something different in mind.

A little history first

We the US got the WRX and we started making parts for them, we saw in japan and in other countries people we replacing their OEM inlet hoses. Over time, we had installed a lot of these for customers and really come to hate the installation of removing the intake manifold. Both of the hoses that we would install were about a 2-3 hour install. To the customer this was a $160-240 install, on top of the $400 part!  All this for about 10HP? This is what sparked us to making this part.

We looked at many different ways to build it.  The criteria had to be easy to install, inexpensive enough so the value equaled the HP gained.  Sounds easy!  I spent a lot of time trying to make some from carbon fiber. This entailed a pattern of the inlet hose, and a mold of the pattern.  A wax casting was made from the mold and a carbon "sock" was pulled over it. When cured we just heated it up and out came the wax.  This didn't work so well.

Before the mold was thrown away we tried one last thing.  A carbon fiber "sock" was pulled over a special made bladder, and inserted into the mold.  With resin soaked into the carbon, and the bladder pressured up the mold, out comes a carbon inlet hose!  Sounds complicated but this is how a lot of these kinds of things are made.  But for a smaller company like us it was messy and time consuming.

So the next best thing was silicone. Silicone is flexible, and this would be great for installation.  After a little engineering and after NOT looking at the stock part, we created our first prototype tool.  Looking at this from an installers point of view we came up with the idea to move the spigots around to make the part installable while keeping the manifold bolted down.  This simple idea not only eliminated the need of the intake manifold coming off, but it eliminated cost in installation fees. 

Present Day Inlet Hose

This polished Stainless Steel tool is what creates the Silicone hose you see today.  And to this day, it has been one our most popular  selling items in our catalog of parts.  This hose is a 5-ply hose with a longer than normal cure time to ensure its stiffness.

Over the years other competitors have come into the market with similar parts, and taken some of the market share.  This has lead us to look to many other methods of building the Inlet hose to make it different and better.  We could make it in an aluminum tube, but someone already does this.  We looked at a cast aluminum part, but not be able to offer it at the same price.  We kept coming back to Silicone because of the installation. Every method we looked back to all had the same problem, installation.  Since this was one of our biggest selling points we had to stick with this. 

Future PERRIN Inlet Hose 

So how can we make the part better?  A very small but damaging issue we had with some of our parts was the reports of them collapsing.  To this day roughly ten out of thousands of parts were returned to us with this issue. The issue was due to the silicone not being cured long enough. While this was a very small issue to us, it was publicly exploited on the internet and made out to be a much bigger problem that it really was.  Again, this small issue could be completely remedied if we made a simple and effective change.  We could add a wire that would run through the middle of the hose and would provide enough support that collapsing issues would be gone completely and still be able to install it! So there we have it!  Along with this, some slight revisions to the included pieces, and instructions were done.  We feel that these changes will make an already great part even better. And with ZERO change in price. 

To add to that we have done some dyno testing with the part and seen some pretty good gains, especially in the land of boost.  When testing parts, we look at 2 different things.  Bolt on power, and retune power. Because we can tune the ECU, it is important to look at both methods to show real world gains and gains after a tune.  For this part, we see great gains with no tuning, which is the beauty of this part.

As you can see, there are 2 very important parts of the RPM band to look at.  The green line represents the boost on our car, with just the intake system installed. The Purple line is done roughly 40 minutes later (more on the time thing in a few) where there is more boost.  The results show the OEM inlet hose is a restriction.  Getting rid of the restriction on the intake side of the turbo makes the turbo more efficient.  A more efficient turbo means the charge temps will drop, making more HP!! 

The power graphs show the turbo spooling up quicker and netting more low end power.  At the same time the slight increase in boost at the upper RPM provides more HP from 5500 RPM. An ECU retuned specifically for the inlet hose could net a few more HP as the turbo runs more efficient.  But for the above test, we are running our Stage 2 mapping that was designed for the Intake system. This is showing the real world HP that other customer should expect to see.

So this all comes around full circle to the title of this article.  37 Minute install wasn't something we pulled out of our rear.  To prove that our hose is simple to install, I some what challenged myself and said I bet I can do it in a half an hour.  Now it had been quite a while since I had install one, but now I had a camera taking pictures over my shoulder, the challenge was on!  I gathered the tools I needed, and started, and along the way, there were a few small parts I forgot to grab which may have added a couple minutes here and there.  After the install was all done, I was surprised that I did it in 37 minutes!  I think had I been a little more prepared (should have grabbed a box off the shelf) and with a little practice 30 minutes is totally doable.  Since I had John h taking pics of the install over my shoulder, we turned the install into a quick video.

This may make some of our dealers that install parts, a little mad, but that is how long it should take.

So the New PERRIN Turbo inlet hose has had a long history with us, and it was time to make a couple changes, changes that we feel will make this part top of its class.  We hope our future customers will find the added power and responsiveness of the engine is worth the 37 minute install.