I had been reading some posts on how you can detect pressure leaks on the cold side with interest since I suspect I might have just such a leak. One post suggested going to the hardware store and finding an PVC end cap that would just fit inside a 3” coupler. With 2 such end caps you could uncouple at/near the throttle body and at the outlet of the turbo and seal your cold side. Prior to putting one of the caps on, he suggested drilling an hole suitable for an air hose fitting and seal it onto that cap. With such a setup, you could dial down the PSI on your Air compressor regulator to a suitable level and, after attaching the air hose you can go around the system using either your ear or soapy water to detect pressure leaks.

That in mind, I went to my local Ace hardware affiliate but couldn’t find and caps that had the outside diameter right at 3”. I *did* however, find these…


Notice they are fully sealed on the ends. All one has to do is drill out the little plastic raised area on the tip (and a little larger for the air hose fitting) and insert the fitting…


You simply insert the plugs into the couplers, tighten the red screw till it’s nice and tight, the hook up the air hose and start testing.
Thanks,
Dave

 

nice i need to find thoes. i've been testing my hot side and using some plumbing parts, but its not easy to get a seal over a vband end.

 

They were in the plumbing section and only $4.99 ea

 

doesnt look like they make them in 2.5.

 

Google found this 2.5"....
2.5" mechanical test plug - Bing Images

 

So how well does the cold side handle 150 psi?

 

I'm sure it would pop a piston or two if it got that high
I tested it at 15.0 psi not 150.0 !
It's all sealed up now. I got it to 14.5 psi today. Trying to fatten up the fuel as it's going to 13.x at 5700 RPM. My duty cycle at that point is 88% with these 60 pounders. I may have to pony up for some of those FIC 1000's or buy another Low Impedence box for my 95#'s.

 

what fuel pressure regulator are you running? you could get a boost referenced one that would add 1lb of fuel for each 1lb of boost. might get your duty cycle down.

 

I had the TPI adjustable for several years, installing it in like '97 or so. Sometime around 2007, the diaphram popped in it and so I went back to a stock non-adjustable FPR. I'm running 43.5 psi @ atmosphere.

I really liked the Acceleronics box w/the 95# injectors but finding that I could zap the box and be stuck on the side of the road, even though I carry a spare PCM in the back hatch(Turbo guys have to be prepared for all kinds of crazy s**t. )

In the next week or so, I hope I can swap the trannies and get one more day at the track, hopefully getting some 1.6 sixty foots.

 

does the stock regulator increase fuel pressure when it see's boost?

 

Yes 1:1.

 

I hear ya on that one. I ordered up a set of 83# Siemens Deka high impedence injectors from FIC about 2 weeks ago for my 408 build. Should be right around 95#s at 58 psi (LSx pressure). I'll let you know how they work out. About half the price of the ID1000 injectors and they should handle 800 hp easy enough. Because daily driver.