My MPI 2014 Viper Tuned by Ulmer Racing

[MrSled]

I had my MPI Viper over at Ulmers on the Track Dyno. I had him assist me on getting my boost set correctly and tuning in my clutching. Machined the secondary for 8DN blet and the primary for top end gains..... here are some numbers.

You can see we picked up 26 track hp on high boost and 21 track hp on low boost by working clutching, waste gate settings, and his hi/low boost switch.

You can see the final gains on top speed from 114.6 MPH to 123.46 MPH after machining.

Quote from Ulmer:
"Track HP vs engine HP, on our Dynojet 360 track dyno anyways, equals about 55% efficiency.

The mathematical equation I use to calculate engine HP from track HP is below.

Track HP / 0.55 = Crank horsepower

Box Stock SR Viper LTX has 73 hp to the track stock = 132.xx crank hp

Tom's SR Viper LTX set @ 5 psi had 98 hp to the track = 178.xx crank hp

Tom's SR Viper LTX set @ 6.5 psi had 110 hp to the track = 200.xx crank hp

Every engine or track dyno will read slightly different. We made 1 run at 7.5 psi that was 116 hp to the track (roughly 211 engine hp) and then we dialed the boost back down.

I can tell you that 5 psi of boost on an MPI kit will add approximately 56 crankshaft HP to the sled."

 

[northof50]

I had my MPI Viper over at Ulmers on the Track Dyno. I had him assist me on getting my boost set correctly and tuning in my clutching. Machined the secondary for 8DN blet and the primary for top end gains..... here are some numbers.

View attachment 98372

View attachment 98373

You can see we picked up 26 track hp on high boost and 21 track hp on low boost by working clutching, waste gate settings, and his hi/low boost switch.

View attachment 98374

View attachment 98375

You can see the final gains on top speed from 114.6 MPH to 123.46 MPH after machining.

Quote from Ulmer:
"Track HP vs engine HP, on our Dynojet 360 track dyno anyways, equals about 55% efficiency.

The mathematical equation I use to calculate engine HP from track HP is below.

Track HP / 0.55 = Crank horsepower

Box Stock SR Viper LTX has 73 hp to the track stock = 132.xx crank hp

Tom's SR Viper LTX set @ 5 psi had 98 hp to the track = 178.xx crank hp

Tom's SR Viper LTX set @ 6.5 psi had 110 hp to the track = 200.xx crank hp

Every engine or track dyno will read slightly different. We made 1 run at 7.5 psi that was 116 hp to the track (roughly 211 engine hp) and then we dialed the boost back down.

I can tell you that 5 psi of boost on an MPI kit will add approximately 56 crankshaft HP to the sled."

I do enjoy reading your posts! Keep up the great work!!

 

[mmaman207]

Huge gains for a little tuning time! Well worth the trip id say.

 

[Yamadog]

Well as most of you know I have had my issues. Finally got mine back from Allen 2 weeks ago. He went through everything incuding a bow full of broked headers, turbo mount, waste gate mount and heat shields. Missing parts on the primary and a ton of wear on the hoses and lines that ere run against frame and motor without any protection and were rubbed badly. He added the 4th injector, installed his clutch kit, fixed all of the issues, machined the secondary for the 8 dn belt. reset the boost controller switch to 9 and 12#'s and did several pulls on the track dyno to finalize clutxhing and helix. Dyno numbers at 12#'s are near 252 hp.

It snowed Yesterday so I went to the shop and installed the Axis shocks and Hygear coupler in the rear skid. I took the sled out around the shop. I do not know the quality or octane of the fuel in the tank so I left it on low boost and went for a spin.

I finally think I have a monster. Throttle response is wicked and when the clutch hits it wants to rip your hands off the bars. The sled squats on launch and lifts the skis to 12" and then the rear couples and takes of like a rocket. It does not feel like it wants to keep on climbing in the nose and all of the energy is pushing me forward. I did not want to push it harder than a few seconds of wot but it is a different sled.

When it had the Evols on it the front with 150#'s in the reseviors and 60 #'s in the main tubes it was too low to get it on the sled lift without picking up on the bumper and now there is 1" of clearance when I roll it under the nose. The rear with 120#'s in the fox float would have close to 3" of sag sitting sationarary and 1-1/2" of set in. Now there is no sag sitting and I have it set with 2" of set in. I cannot wait to launch ot off a berm and see how it lands - hopefully no more damaged wrists from front end hits.

 

[Yamadog]

Oh crap what I really wanted to say was hats off to Allen I think he did an incredible job and made an ok sled into the ride I really wanted.

 

[titanrcr]

Oh crap what I really wanted to say was hats off to Allen I think he did an incredible job and made an ok sled into the ride I really wanted.

It sounds like you have a real beast now. Any idea why you had so many broken parts? Were these aftermarket parts, mounts that broke? Something missing from the primary, ouch!
Going into my first season with a Viper, do I need to beef up the headers, mounts etc. Guess all the hoses should be looked at for potential rubs as well. Only thing I've done so far is to junk the stock tri-hub rear axle and install the JT oversize 4 wheel kit. I'll be running boost as well.

 

[Yamadog]

Well a lot of it was due to the original install by Hauck motorsports. Then the motor blew and everythng was removed and then re-installed. The safety bolts in the clutch arms were Haucks fault and most of the broken parts had to be their fault. They just re-installed everything with cracks and then they let go in the last 400 miles. They had to see all of the rubbing when they rebuilt the motor and still did nothing to protect it. Not sure on the header we will see on the new one if it holds up. I ran the tri hub all last season but just ordered the turbo dynamics 4 wheel cause I checked mine last night and it feels like the bearings are junk.

 

[sheetwright]

Ya I too had a terrible install with Hauck. Cost me a ton of dough also.I hope your rework from them was better than mine. Ulmer is stand up, and is a whiz with the clutching on these boosted engines