ZR-1 Net Registry Forums  

Go Back   ZR-1 Net Registry Forums > C4 ZR-1 > C4 ZR-1 Technical Postings

Reply
 
Thread Tools Display Modes
Old 08-30-2020   #1
Zman
 
Join Date: Jun 2019
Location: WI
Posts: 131
Default Switching up a DRM 385

I currently have a DRM 385 with 4:10's and upgraded brakes. I'm thinking of switching back to 3:45's with a 22lb flywheel. I'm also adding DRM coil overs. Does anyone support this setup or suggest a different gear ratio or a different weight flywheel. I just sold a Henderson 368 with coil overs, 4:10s, and a 13.5# flywheel. I'm trying blend these two together per say. Give me some feedback?
Zman is offline   Reply With Quote
Old 09-01-2020   #2
Mikey
 
Join Date: Jul 2020
Location: Nashville TN
Posts: 308
Default Re: Switching up a DRM 385

I'm not really sure why you sold the 368, but THANKS!
Mikey is offline   Reply With Quote
Old 09-02-2020   #3
Zman
 
Join Date: Jun 2019
Location: WI
Posts: 131
Default Re: Switching up a DRM 385

It all came down to sound. The 368 sounds like thunder going down the road and required ear plugs. My 385 sounds like a jet engine no ear plugs required. That was the deciding factor. Sold my house, new house has 2 less spots to park. The last owner was generous to me, so I passed it on! Enjoy your Henderson 368!

On a side note I decided to go with 3:78 s in the 385.

Last edited by Zman; 09-02-2020 at 07:22 AM.
Zman is offline   Reply With Quote
Old 09-02-2020   #4
Zman
 
Join Date: Jun 2019
Location: WI
Posts: 131
Default Re: Switching up a DRM 385

Current path: 22# Jerrys Gaskets?s flywheel, Dana 3:78 gears with correct speedo gear, and DRM coil overs.
Attached Images
File Type: jpg 6A13F15C-5355-4421-82C5-B76862BCCF28.jpg (223.1 KB, 52 views)
File Type: jpg B702445F-26E3-4313-B676-8C3EC30B0D20.jpg (188.8 KB, 43 views)
Zman is offline   Reply With Quote
Old 09-03-2020   #5
rkreigh
 
Join Date: Jan 2004
Location: Alex VA
Posts: 1,087
Default Re: Switching up a DRM 385

Quote:
Originally Posted by Zman View Post
Current path: 22# Jerrys Gaskets?s flywheel, Dana 3:78 gears with correct speedo gear, and DRM coil overs.



great choice. the stock gears are a bit too tall to make 5th gear work well on highway. Even with the stroker and more torq, with the lightweight flywheel the car has less inertia to get the car moving so that gear will work better. The 385 is a great engine, enjoy!
__________________
95 390 LPE ZR1 (505 rwhp)
LSV = Lingenfelter Super Vette
Twin Turbo 2003 Z06 (800 RWHP)
rkreigh is offline   Reply With Quote
Old 11-06-2020   #6
Zman
 
Join Date: Jun 2019
Location: WI
Posts: 131
Default Re: Switching up a DRM 385

New car in the stable! DRM 385CI, 3:78 gears, 15 lbs Aluminum flywheel with dual disc clutch, DRM coil overs, Pete tuned the car for 93 octane after installing everything. Very impressed with this set up. Wow!
Attached Images
File Type: jpg ADCEBE9A-7794-4A14-BE9D-7EA47BCBC440.jpg (200.6 KB, 51 views)
File Type: jpg 25B988D7-E5BA-41C2-A7DD-D5E646CED996.jpg (217.4 KB, 47 views)
File Type: jpg 5B027880-192F-4865-B0AB-ADDB0BB90764.jpg (238.9 KB, 57 views)
Zman is offline   Reply With Quote
Old 11-07-2020   #7
Demps
 
Demps's Avatar
 
Join Date: Jan 2006
Location: Niceville
Posts: 997
Default Re: Switching up a DRM 385

I?d imagine that?s just about perfect. What do you think?
Ted
Demps is offline   Reply With Quote
Old 11-08-2020   #8
Zman
 
Join Date: Jun 2019
Location: WI
Posts: 131
Default Re: Switching up a DRM 385

Quote:
Originally Posted by Demps View Post
I?d imagine that?s just about perfect. What do you think?
Ted
I am having a learning curve on the Clutch. I missed 3rd a few times today. It is a Ram 9.5 dual disc clutch kit from Jerrys Gaskets. I just got to the 500 mile break in on Friday. It operates way differently than what I am used to.

Im still on the fence about the aluminum flywheel. It is quiet at idle with the clutch in or out, but makes considerable noise when driving hard in the twisties.

Love the 3:78 gears. First gear is now usable again. I always just went to second gear around a corner with the 4:10 gears. They run much quieter than the 4:10s did.

Coil Overs are a must on WI roads!

72 degrees on November 8th in WI today!
I will see if I can master the clutch today.

Thanks for asking!
Attached Images
File Type: jpg FAC50AAE-F6CE-415C-8C9F-DB68E02EE0BC.jpg (234.5 KB, 50 views)
File Type: jpg 6C6D1D96-C2A9-4196-A41C-8F54843EAC85.jpg (170.0 KB, 44 views)
Zman is offline   Reply With Quote
Old 11-08-2020   #9
Zman
 
Join Date: Jun 2019
Location: WI
Posts: 131
Default Re: Switching up a DRM 385

Clutch learning curve solution. REMOVE the bunched up floor mat out from under it! I love the feel of the clutch and no more missed shifts! I had my mother with me for the first 160 miles after breaking in the clutch. Today while out alone I was able to run at Rpms that did quiet the transmission rattling down. All I know is the other two couldn?t keep up even with my mom along!
Attached Images
File Type: jpg 8C596BB2-994D-4C7B-B4B7-625B58FCA61D.jpg (298.8 KB, 27 views)
File Type: jpg 76B835AD-6C49-4B53-A917-63ACB13B9180.jpg (279.7 KB, 25 views)
Zman is offline   Reply With Quote
Old 11-08-2020   #10
Hib Halverson
 
Join Date: Jun 2005
Location: CenCoast California
Posts: 899
Default Re: Switching up a DRM 385

The stock axle, during development a 3.54, but virtually all of production a 3.45, was picked because GM wanted the car to have a top speed of 180-mph in fifth gear so the ratio was selected such that, at the engine's power peak, it would be going about 180.

A good 368 or 385 is going to not only make more power but will likely have a higher power peak, so the car could still make 180 but with a slightly lower axle.

When I owned Barney, it's Automasters "Street Skinner" 350 made about 505-hp and 413 at the tire, but it did that about 500-rpm higher. My "plan book" always had a change to a 3.73 or so axle ratio listed. I'd have gained some acceleration and maintained the coveted 180-mph top speed. Never got a chance to do that.

Also, Barney had a McLeod aluminum flywheel and I never had trouble driving that with the car's stock 3.45 axle ratio. "rkrieh" seems to think there's a problem with an aluminum wheel and the stock axle, but, in 20 years of driving Barney in all kinds of situations, I never had trouble.

I have aluminum wheels in both my C5 ZO6 and my C6 ZO6. Both cars have stock 3.42 axles and I have no problem driving them.
__________________
Hib Halverson
Technical Writer
former owner 95 VIN 0140
current owner 19 VIN 1878
Hib Halverson is offline   Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 12:39 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright ZR-1 Net Registry 2020