The VIPER Garage

How To Instructions => How-to section => Topic started by: RTTTTed on August 24, 2013, 06:05:51 PM

Title: Trap Door Oil Pan Mod & Windage Tray Upgrade
Post by: RTTTTed on August 24, 2013, 06:05:51 PM
Having the rod bearing wear out with less than 60,000 miles on my modified supercharged engine I made many phone calls and spoke with Larry Macedo, Sean Roe and Todd at Arrow Racing engines about short term rod bearing life.  My engine was built by Macedo Motorsports back in 2003 and Larry knows his business.  The Roe Racing blower kit shouldn't have worn the brearings as this engine is nearly all highway miles with seldom any abuse or WOT useage.  I emailed Todd at Arrow Racing engines as Jtin/Joel Fortin also was having issues with rod bearing early failure.  Todd said, "Third or fourth bearings?  That's normal."  Joel has plugged his crank's Crossdrilling as that seems to increase the rod bearing oil supply.  Todd suggested the ACR oil pressure bypass valve and the special Viper oil filter as necessary.  No ACR oil pressure bypass valves are available - even used ones.  :(   

Although I do compete (read that as "Kick Ass") I drive thousands of miles at 1250rpm and then race the car 3 or 4 times.  Road racing has been absolute minimium useage and I'veonly been around a few road courses and then only short sessions.  I expected the engine to last over 100,000 miles.  When I pulled the Ross forged pistons out there was only a little wear on the rings and insignificant wear on the rings and cylinder walls (about .0005") with about .010" wear shown in the rings end gap.  All the main bearings and the thrust bearings looked like new.  Engine was in good shape since I'd pulled it apart before the bearings failed.

Cylinder walls were glazed and my valve seals were loose so the engine was sucking oil past the valve seals.  Ordering parts I ordered CL77 rings (same as what was in the engine) and from I ordered his swinging trap door oil pan kit.  I'd heard that road racing required this modification  or the engine was prone to failure if road raced often.  Jtin's crank modifications are in a different "How To" thread on this site.  Here is the How To on the Part's Rack oil pan trap door upgrade.  For the couple hundred bucks it cost I highly recommend it.

I pulled the 10 Qt. oil pan from my 2001 Viper GTS.  Easily done with the car on jackstands.  First drain the oil and remove the oil filter.  I recommend filling a new filter with oil and installing that so that the oiling system is closed at the filter end.  The oil pan bolts are easily accessable from under the car.  Start at one end and remove all the bolts leaving one slightly loose to support the pan while the rest are removed, then removed the loose bolt and carefully lower the oil pan to the floor.  Be very careful to lower the pan evenly so as not to damage the alum REUSEABLE "oil pan gasket".  Drag the pan out from under the car and wash it carefully.  Inspect the bottom of the pan carefully for filings and "chunks" of metal which would indicate internal engine problems.  Removing the oil pan should be easily accomplished in less than an hour.  After rinsing the oil and sludge out of the pan remove the stock oil pan baffle.  Again clean the oil pan and now the screws holding the suction screen can be removed from the pan's floor and the suction passage can be washed clean as well.  Inspect the screen for junk stuck under the brace and make certain that everything is spotlessly clean. 

Open the kit's bags and wipe all the parts to clean any dust, etc. that may have gotten on the pieces.  Install the trapdoors the way that they are written, F or front towards the front of the engine and R or rear towards the back of the engine.  The baffle/trap doors are made with special brackets that have an extra angle to keep the doors from sticking open and the spot welded hinges also contain springs.  The front trap door opens towards the rear of the engine so that under acceleration the front trap door opens and allows the oil to go from the front of the sump to the middle section while the rear door closes and keeps the oil from the middle and the front in the middle of the pan to feed the oil pumps suction tube.  When braking the rear door opens allowing the oil to the middle (suction) section while the front trapdoor closes trapping the oil in the middle section where the oil pump suction opening is.  This is an excellent upgrade.  The factory baffles in the pan are angled in such a way as to expand the oil capacity of the middle/suction pan section!  Lay the trap doors in place with the top brackets lined up with the screw holes (no screws). 

Place the top baffle plate (acts like a windage tray) over the screw holes and make certain that the dipstick hole is in the correct position (front passenger side on my pan).  Start all the 8 screws in their holes, I used Locktight on all the screws to make certain that they do not loosen themselves.  Push the front trapdoor so that the door is closed agains the pan baffles and tighten screws.  Reach throught the baffle plate holes and make certain that the trapdoor works properly and doesn't stick.  Use the same method to screw, tighten and then check the rear trap door's movement.  Then tighten the two front end screws and two rear screws.  Double check all screws for tightness and you're finished!

If you didn't puncture the silicone "pouches" of the oil pan gasket, reuse it and reinstal the oil pan.  Check the dipstick insertion, fill with oil and start engine.  This modification will not affect the height of the oil inside the pan so the dipstick should read the same oil level as before.  This modification should help your engine's oiling and make your Viper run longer than without it.

Title: Re: Trap Door Oil Pan Modification
Post by: RTTTTed on January 20, 2016, 05:28:41 PM
If you removed the rod cap to check your rod bearing it would drain the oil from the crankshaft and the oil passages about that main journal.  You can be a little safer by unplugging the coils and spinning the engine over for a few minutes to fill the engine with oil before loading the bearings and crank by the engine actually running ...   Then plug the coil connector back together and start the engine.

Here's the #3 bearing from my engine with only 50,000mi on the engine.  CL77 bearings are the Industry standard for HP. 

As seen in the second pic there were many rod bearings worn out.  I've only run the road courses a few times.  Mostly I enjoy long drives and acceleration contests.  Half and Mile events my preference.  I changed out 7 of the rod bearings.
Title: Re: Trap Door Oil Pan Modification
Post by: RTTTTed on October 12, 2016, 12:04:35 AM
Whenever I take something apart I look at the flow pathways.  In this case I have the oil pan off and am trying to contain the oil near the pick up to minimize oil starvation when accelerating, turning or stopping.  Any further improvements I can make are a bonus!

So when you drop the oil pan look at the fitting of the pan pick up conduit, the aluminium plate gasket and the engine block conduit.  They aren't the same size and the holes don't line up that well ... Like head porting there is free hp and better oil delivery and pressure when the SUCTION side of the pump flows easier.  Higher volume and higher pressure (which equals engine safety) oil is needed with modern emissions based engines.  Gen 1/2 Vipers don't oil well at 6000rpm so all upgrades are an improvement.  Match porting the oiling passage mating surfaces is an excellent upgrade and makes the engine safer as well as faster.

I stuffed cloth deep into the oil pick up conduits to minimize aluminium filings from getting too far into the conduit and help with cleaning.  I used a small round file to clean and smooth the oil passage entry into the engine block.  I found casting flash which I broke off at the block opening.  Restrictive and a potential catastrophic engine failure if the flash broke off and got sucked into the oil pump.  Using the smal round file with the cutting angle DOWN I filed the obstruction left when the bottom of the block was machined flat.  I used a fine chainsaw file to make the opening smooth and remove any filing marks from the courser round file.  I did the same with the oil pan and filed both openings to better match and line up with each other. 

I learned the oil passage match porting from working and blueprinting 2.2L turbo engines.  A 175bhp engine would gain 4hp when the oil passage into the block was filed slightly to remove some of the angle that the oil had to change to enter the block from the oil pump.  Discovering the 7% restriction at the block opening would cause a big difference in the performance of the engine's oiling system plus a hp gain because of less restriction! 
Title: Re: Trap Door Oil Pan Modification
Post by: RTTTTed on January 23, 2017, 06:54:55 PM
Recently Brett Mitchell dropped his oil pan during a mild TT build and his 2001 ACR needed all new rod bearings.  Luckily he checked BEFORE he lost oil pressure and the crank and engine are fine.  New rod bearings and he's ready for another 100,000mies since he's added the trap door kit from Roe Racing.  He's also planning to use Mopar VIPER oil filters from now on.

Brett's post brought out a post from Aaron Hioffman whose engine spun a rod bearing at 35,000 miles.   
Title: Re: Trap Door Oil Pan Mod & Windage Tray Upgrade
Post by: RTTTTed on March 07, 2017, 02:05:50 AM
Roe Racing also sells a similar trap door pan kit.  They were included in a Viper GTS article from a Mustang Tuner for MotorIQ.
They have some pictures posted that show the action of the trap door pan kit and the differences between the early Gen 2

Pic 1 shows the stock Oil pan with the top baffle plate removed.  Under acceleration at say .... 1 G force the oil would try to go to a 45 degree angle up thje back of the pan and engine whcih would caiuse the oil to interfere with the spinning of the  crankshaft, wasting hp as the crankshaft pushes through the oil at supersonic speeds.  The antifreeze in this tilted pan shows just a small amount nof liquid but see the angle and where the liquid is?

Pic 2 shows the trap door pan in action.  The front trap door closes under Deceleration and is open under acceleration allowing the oil to flow from the front to the middle section where the oil suction is.

Pic 3. shows the early Gen 2 windage tray and the "cream Puff" windage tray which came in the200 to 2002 engines with the 10.5 qt oil pan

pic 4.  shows the early Gen 2 oil pan whcih holds 9 qts and the 1" taller newer 1.5qt oil pan
Title: Re: Trap Door Oil Pan Mod & Windage Tray Upgrade
Post by: RTTTTed on March 07, 2017, 02:17:39 AM
Both the Gen 2 oil pans are the same - except the later windage tray has rounded cutouts allowing the oil to drain back to the pan much faster as the early tray requires much of the oil to flow all the way down the side of the tray to get acess to the baffle plate above the oil galleries.  The earlier windage tray can benefit from the newer styke cutouts  and tin snips can create a newer pan from an older model.

Another big improvement to the Viper's oil drain back is created by drilling 3/4" holes through both windage trays under the crank scrapers!

I've added a picture showing the crank scarper from the top of the windage tray.
Title: Re: Trap Door Oil Pan Mod & Windage Tray Upgrade
Post by: RTTTTed on March 05, 2018, 10:01:48 AM
I dropped the pan on a 97 GTS to check rod bearings and install a trap door oil pan from Roe Racing before porting the heads and installing a Roe Racing 710 camshaft, rockers, springs etc.  ALL rod bearings were damaged but the main bearings were good.  I changed the rod bearings, trimmed the windage tray and installed the trap door pan kit.  Tuning was an issue and this car went to Dan Cragin's shop since local Portland shops couldn't get the SCT tune correct but Dan did.  He also requires checking the rod bearings to work on car and he found that the new bearings were prefect.  He went over the car found a computer feedback problem and sent me an email that I'd done a good job.  That car is awesome now and 550whp/570wtq and a great driver even with the big camshaft. 
     I recently bought a 1998 Hennessey GTS with SVS TT system (875whp/987wtq) and only 900mi on a new build (rods, pistons, cam, jesels, GG heads etc).  When I drove the car it took several minutes for the oil pressure to com up over 20psi!  After a couple miles the oil pressure came to 47psi.  Weird but it seemed ok once it warmed up.  I drove the car 3.600mi to washington at end of January where I loaded it into my trailer and finished the trip to the "Great White North" protected from the ice and snow.  Low oil pressure on start up in the cold again.  Once inside the shop I put the car on blocks and dropped the oil pan.  Rod bearings were all junk.  I dropped 5 and replaced 3 but I did have to polish 2 crank journals.  I trimmed the windage tray to cream puff engine style with tin snips.  The rod bearings were standard so it hadn't had a bearings failure and I had no idea what caused all the rod bearings to fail.  Perhaps the 15/50 racing oil???  The oil filter I removed was a proper Viper filter from Mopar.  I worried and then called Kevin at Exotic Engines and ordered an external oil pump and wet sump system. 
Title: Re: Trap Door Oil Pan Mod & Windage Tray Upgrade
Post by: RTTTTed on March 05, 2018, 12:45:33 PM
Part number for TM/Tri Metal std rod bearings is CB481p.