Keith Posted March 8, 2008 Posted March 8, 2008 I need to install a smaller restrictor plate in my LT1 to get under the power levels for CMC for 2008. I have dyno-tested 38, 37, 36, and 35mm restrictor plates. Here are my test results: Note that this car has underdrive pulleys (more power) and still has the cat installed (same-as-stock power, I assume) with everything else essentially stock. I would like to get the correct plate in there the first time. I am shooting for 235 hp (for a safety margin) and was wondering if anyone with an LT1 would be willing to share their experiences with power levels with the 34mm and 33mm restrictor plates. Thanks. Quote
Glenn Posted March 8, 2008 Posted March 8, 2008 i run a 31mm. i'm at 216 hp and 301 tq. most here run the 33mm to stay under 230/300. my car is a freak. Quote
Keith Posted March 9, 2008 Author Posted March 9, 2008 (edited) FYI, 36mm netted me a 16hp loss. From a 37 or from no restrictor? Edited March 9, 2008 by Guest Quote
Keith Posted March 9, 2008 Author Posted March 9, 2008 i run a 31mm. i'm at 216 hp and 301 tq. I sure would like to have that torque number. I guess I'll put my 33mm in there and see what the dyno says. Quote
Keith Posted March 9, 2008 Author Posted March 9, 2008 33mm installed. Seems like the safe choice. Thanks. Quote
Glenn Posted March 10, 2008 Posted March 10, 2008 i'll give you a better idea again on Friday when i get this motor cert'ed for the '08 season. i'll have a CMC HP/TQ legal size, a CMC-2 HP/TQ legal size, and an unrestricted nuber. Quote
AllZWay Posted March 10, 2008 Posted March 10, 2008 I have a 32mm and I am at 228hp and about 289 torque. Quote
y5e06 Posted March 10, 2008 Posted March 10, 2008 32mm plate (originally sourced from Al) gets me 230/302. however, post race I usually weigh 3250-3280. it did 275/315 uncorked last year. Quote
Glenn Posted March 22, 2008 Posted March 22, 2008 made 5 pulls today w/ the 31mm in place. got 216-223hp and 288-296tq. the motor has a full season on it w/ new bearings and head gaskets for this season. i ran a full weekend on it last weekend and dyno'ed today. i also pulled a peak of 278hp/319tq unrestricted. 93 LT1 speed density car. this jives w/ the 285/325 i pulled on the OEM stock unopened motor when i built the car on the LGM dyno back in Feb 2005. the dyno is at about 500 feet. Quote
Dave Schotz Posted March 23, 2008 Posted March 23, 2008 Nice dyno runs Glenn... that's the nice thing about the LT1 (IMO)... CMC2 numbers perfectly 'unrestricted'... and CMC-1 Numbes... perfectly... restricted! Ncie to have options! I knew I should have gotten an LT1! My goal will be to build the 3rd Gen to the numbers in CMC... and the LS1 to the numbers in CMC2. My LS1 car is plenty strong... and will be able to run CMC2 numbers for years w/ restrictors... but my 3rd gen is in need of some help... down about 15HP & TQ... hopefully we'll find it throughout the season! Peace! Dave Quote
Glenn Posted March 23, 2008 Posted March 23, 2008 LT1's in CMC-2 are limited to 260 hp and 310 TQ (i think). so i would still need the restrictor. i have no plans to run CMC-2 though. Quote
Lady in Nomex Posted March 23, 2008 Posted March 23, 2008 LT1's in CMC-2 are limited to 260 hp and 310 TQ (i think). so i would still need the restrictor. i have no plans to run CMC-2 though. See Power and weight Table #3 in the rules for LT1 CMC2. Hp starts at 260 and ends at 270; tq starts at 310 and ends at 324. Quote
Glenn Posted March 23, 2008 Posted March 23, 2008 from my point of view, there is nothing over 260/310. the weight penalty is just too big to run any more that 260/310. Quote
Tony G Posted March 25, 2008 Posted March 25, 2008 Oh yeah, then come to Fontana and watch the heavy high HP cars go by you I agree though,I would take the light lower HP car over a High HP car unless you were doing nothing but high speed tracks with only a few turns. Tony Guaglione Quote
Members Al F. Posted March 28, 2008 Members Posted March 28, 2008 In now its third season, my LT1 runs a 33mm plate to yield just over hp and just under tq (233/290 I believe). Thanks John, she's still tickin' Quote
Keith Posted April 14, 2008 Author Posted April 14, 2008 I was dynoed on Saturday at Mid Ohio. With the 33mm plate in there, the dyno read: Pull #1: 234.0/294.7 Pull #2: 235.0/297.4 Pull #3: 235.0/299.2 HP was right where I figured. I was surprised that the smaller plate didn't pull more than 1 ft-lb of tq when compared to the 34mm plate. With the 34mm plate, I had 238/298 IIRC. Thanks for the input. Quote
Members Al F. Posted April 14, 2008 Members Posted April 14, 2008 Fantastic numbers Keith...no excuses! Quote
Keith Posted April 14, 2008 Author Posted April 14, 2008 Excuse? I suck. However, the f-bodies dominated the Mustangs all weekend at Mid Ohio. More fuel for the fire? No, wait, there WERE NO Mustangs. Hahahahaha Quote
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