Circle D converter
Thread Starter
Instructor
Joined: Oct 2013
Posts: 134
Likes: 1
From: McAllen Texas
Circle D converter
Those of you running a Circle D converter, what size did you go with 245mm or 258mm? what stall speed? How did it affect your drivability from a stop?
My tuner recommended a 3200 rpm 258mm and Circle D recommended a 3400-3600 245mm converter.
I drive the car on weekends and not looking to give it half throttle to get the car to move.
Goal is to dip into the 9's
will be adding:
stage 2 cam spec'd by tuner
circle d converter (one of the above)
might get ported heads (any recommendations?)
current mods:
nitrous 100-150 shot
NO stand alone fuel cell
lt headers
catless x pipe
zr1 tb
ported stock intake manifold
afe cold air
e85
My tuner recommended a 3200 rpm 258mm and Circle D recommended a 3400-3600 245mm converter.
I drive the car on weekends and not looking to give it half throttle to get the car to move.
Goal is to dip into the 9's
will be adding:
stage 2 cam spec'd by tuner
circle d converter (one of the above)
might get ported heads (any recommendations?)
current mods:
nitrous 100-150 shot
NO stand alone fuel cell
lt headers
catless x pipe
zr1 tb
ported stock intake manifold
afe cold air
e85
Safety Car
Joined: Jul 2009
Posts: 3,755
Likes: 190
From: Baton Rouge LA
St. Jude Donor '14, '16
Circle D recommended a 245 with nitrous kind of surprised honestly, but when it's locked I guess it doesn't really matter.
I'm running a 258 "2d" which is around a 3400-3600 in mine. Really wish I did the converter from the start, it feels amazing really. No issues at all. My converter was spec'd for a d1sc build with a goal of around 750hp.
Current mods are:
cam motion supercharger cam
circle d 2d
msd
95
vararam
2" tsp headers
flex fuel (only get 69% e here)
drag pack
My best et is a 10.18 at 133 but then I destroyed an axle. I have a feeling my car should dip into the 9s as it sits if I can get it together before the weather gets warm.
I'm running a 258 "2d" which is around a 3400-3600 in mine. Really wish I did the converter from the start, it feels amazing really. No issues at all. My converter was spec'd for a d1sc build with a goal of around 750hp.
Current mods are:
cam motion supercharger cam
circle d 2d
msd
95
vararam
2" tsp headers
flex fuel (only get 69% e here)
drag pack
My best et is a 10.18 at 133 but then I destroyed an axle. I have a feeling my car should dip into the 9s as it sits if I can get it together before the weather gets warm.
Team Owner
Joined: Jan 2007
Posts: 29,063
Likes: 1,839
From: cookeville tennessee
ttt
I did the 248 with only a 2800 stall with this car having the set up like it does that is all I did. But will not go crazy like I did in the c5.
Mod's
BTR stage II cam
circle D 2800 stall
A/A TI with small upper pulley
All forged motor with ported heads from Cajun
LG 1 7/8 headers but looking to put on 2 inch headers
RPM 3:42 rear with wavetrack & 300m halfshafts
solid 3 1/4 inch C.F. driveshaft with NO couplers
driveshaft axles.
MSD ported intake & meth with z06 pump & inj.
LG motor & rear end solid mounts.
Car runs great. Circle D is the only way to go here in a converter.. Robert
Mod's
BTR stage II cam
circle D 2800 stall
A/A TI with small upper pulley
All forged motor with ported heads from Cajun
LG 1 7/8 headers but looking to put on 2 inch headers
RPM 3:42 rear with wavetrack & 300m halfshafts
solid 3 1/4 inch C.F. driveshaft with NO couplers
driveshaft axles.
MSD ported intake & meth with z06 pump & inj.
LG motor & rear end solid mounts.
Car runs great. Circle D is the only way to go here in a converter.. Robert
Last edited by robert miller; Feb 28, 2020 at 09:07 PM.
Pro
Joined: Nov 2014
Posts: 687
Likes: 83
From: Fort Worth Texas
Circle D Pro 258mm @ 3700-3800 Converter.
How did it affect your drivability from a stop? - It launches really well. It's very streetable and well mannered on public streets. Don't get me wrong, it's definitely noticeable but very minor.
Current Mods:
TS&P fully built 416 stroker motor
ECS 2200 Centrifugal
Custom Intercooler Setup
TS&P PRC Heads
Forged Callies Magnum Crank
Forged Callies I-Beam Rods
Forged Mahle Racing Pistons
TS&P VVT-3 Cam (with bigger fuel lobe)
American Racing Headers 2" - 2 1/8" x 3 1/2" collectors
Corsa Extreme Exhaust, no cats
Supplemental / Secondary Fuel System
Prometh / Alky Control hybrid Methanol System with (9) meth injectors
Bigger Injectors
Custom MSD Airforce Intake
(Several other small / not mentioned parts or mods)
Worked closely with Texas Speed on this build. It should stand the rigors of up to 1300+ horsepower pretty consistently. Patiently waiting on the V15 (which it seems that it will never be released). Sigh.
How did it affect your drivability from a stop? - It launches really well. It's very streetable and well mannered on public streets. Don't get me wrong, it's definitely noticeable but very minor.
Current Mods:
TS&P fully built 416 stroker motor
ECS 2200 Centrifugal
Custom Intercooler Setup
TS&P PRC Heads
Forged Callies Magnum Crank
Forged Callies I-Beam Rods
Forged Mahle Racing Pistons
TS&P VVT-3 Cam (with bigger fuel lobe)
American Racing Headers 2" - 2 1/8" x 3 1/2" collectors
Corsa Extreme Exhaust, no cats
Supplemental / Secondary Fuel System
Prometh / Alky Control hybrid Methanol System with (9) meth injectors
Bigger Injectors
Custom MSD Airforce Intake
(Several other small / not mentioned parts or mods)
Worked closely with Texas Speed on this build. It should stand the rigors of up to 1300+ horsepower pretty consistently. Patiently waiting on the V15 (which it seems that it will never be released). Sigh.
Last edited by officermartinez; Mar 8, 2020 at 11:48 AM. Reason: added to list
Pro
Joined: Nov 2014
Posts: 687
Likes: 83
From: Fort Worth Texas
Thank you sir. I appreciate the compliment! I'm hoping I get the car back today... shredded our 6L80E trans about 3 weeks. The Circle D converter was sent back to Circle D and after it was inspected, it was given a clean bill of health. The transmission itself, no so much. Haha! Bought an entire new trans from Chevrolet Performance... Even came with a 12 month warranty.
Team Owner
Joined: Jan 2007
Posts: 29,063
Likes: 1,839
From: cookeville tennessee
Thank you sir. I appreciate the compliment! I'm hoping I get the car back today... shredded our 6L80E trans about 3 weeks. The Circle D converter was sent back to Circle D and after it was inspected, it was given a clean bill of health. The transmission itself, no so much. Haha! Bought an entire new trans from Chevrolet Performance... Even came with a 12 month warranty.
That is funny on the 12 month warr well at least you have a full season to try & brake it then when you take it back you can say
JUST DRIVING DOWN THE ROAD AT 80 MPH & the dam thing started doing a big clunking sound.
Really good luck and the car looks really nice under the hood one of the best I have seen in the c7... Robert
