3.55 LSD in HQ with Chevy 350 Options

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Guest		#1 Posted : Friday, 11 April 2008 6:55:02 AM(UTC)
Rank: Guest Groups: Guests Joined: 2/09/2015(UTC) Posts: 43,977 Was thanked: 5 time(s) in 5 post(s)		Hello all. I am thinking of putting a 3.55 LSD 10 bolt into my HQ Coupe. It has a mild Chevy 350 and Supra 5 speed. Any thoughts? The 350 has just been re-built. How should i break it in?

Guest		#2 Posted : Tuesday, 15 April 2008 1:48:26 AM(UTC)
Rank: Guest Groups: Guests Joined: 2/09/2015(UTC) Posts: 43,977 Was thanked: 5 time(s) in 5 post(s)		hi mate if i was to fit a 350 in my holden i would be looking at a 3.08 or 2.78 ratio as the 3.55 will be to low. im running a 253 with a 2.78 with a m20 4 speed box and its very good on the open road. when running in the 350 , for the frist 1000ks take i

Guest		#3 Posted : Tuesday, 15 April 2008 1:48:26 AM(UTC)
Rank: Guest Groups: Guests Joined: 2/09/2015(UTC) Posts: 43,977 Was thanked: 5 time(s) in 5 post(s)		hi mate if i was to fit a 350 in my holden i would be looking at a 3.08 or 2.78 ratio as the 3.55 will be to low. i'm running a 253 with a 2.78 with a m20 4 speed box and it's very good on the open road. when running in the 350 , for the frist 1000k's tak

HK1837		#4 Posted : Tuesday, 15 April 2008 6:47:40 AM(UTC)
Rank: Veteran Reputation: Groups: Moderator, Registered, Veteran Joined: 1/03/2005(UTC) Posts: 14,898 Thanks: 1 times Was thanked: 558 time(s) in 533 post(s)		3.55 is a pretty good ratio with a 5-speed if the tyres arent too low in profile on 14" rims. A 3.36 would probably be optimal with a 350. _______________________________________________________ If we all had the same (good) taste, who would buy all t
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HK1837		#5 Posted : Tuesday, 15 April 2008 6:47:40 AM(UTC)
Rank: Veteran Reputation: Groups: Moderator, Registered, Veteran Joined: 1/03/2005(UTC) Posts: 14,898 Thanks: 1 times Was thanked: 558 time(s) in 533 post(s)		3.55 is a pretty good ratio with a 5-speed if the tyres aren't too low in profile on 14" rims. A 3.36 would probably be optimal with a 350. _______________________________________________________ If we all had the same (good) taste, who would buy all
		_______________________________________________________ If we all had the same (good) taste, who would buy all the Fords?
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Guest		#6 Posted : Friday, 18 April 2008 7:03:02 PM(UTC)
Rank: Guest Groups: Guests Joined: 2/09/2015(UTC) Posts: 43,977 Was thanked: 5 time(s) in 5 post(s)		Thanks for your input. Great help.

mrhqute		#7 Posted : Sunday, 20 April 2008 6:51:24 AM(UTC)
Rank: Member Reputation: Groups: Registered Joined: 28/03/2008(UTC) Posts: 69		You want an overall first gear ratio of around 10:1 for optimum acceleration. I had 4.11 gears with my muncie 2.52 first. The supra box has a 3.285 first gear, so you'd want a rear ratio of about 3.08:1 to match it. Ross
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mrhqute		#8 Posted : Sunday, 20 April 2008 6:51:24 AM(UTC)
Rank: Member Reputation: Groups: Registered Joined: 28/03/2008(UTC) Posts: 69		You want an overall first gear ratio of around 10:1 for optimum acceleration. I had 4.11 gears with my muncie 2.52 first. The supra box has a 3.285 first gear, so youd want a rear ratio of about 3.08:1 to match it. Ross
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HK1837		#9 Posted : Sunday, 20 April 2008 6:50:52 PM(UTC)
Rank: Veteran Reputation: Groups: Moderator, Registered, Veteran Joined: 1/03/2005(UTC) Posts: 14,898 Thanks: 1 times Was thanked: 558 time(s) in 533 post(s)		Problem then is 5th gear becomes a bit tall, but a 350 should handle it if it has a dual plane manifold and not too big of a cam. _______________________________________________________ If we all had the same (good) taste, who would buy all the Fords?
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mrhqute		#10 Posted : Tuesday, 22 April 2008 5:50:04 AM(UTC)
Rank: Member Reputation: Groups: Registered Joined: 28/03/2008(UTC) Posts: 69		I guess the trade off is having an unusable 1st or an unusable 5th. I hardly ever use 5th, except on a freeway, so I prefer a useable 1st. Just my opinion of course. Ross
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HK1837		#11 Posted : Tuesday, 22 April 2008 6:45:13 AM(UTC)
Rank: Veteran Reputation: Groups: Moderator, Registered, Veteran Joined: 1/03/2005(UTC) Posts: 14,898 Thanks: 1 times Was thanked: 558 time(s) in 533 post(s)		And a valid opinion as well. I also often suggest people rebuild an aussie 4spd as an M22 and use a 2.78:1 diff rather than retrofit a 5spd. This gives you a good 1st and a 4th gear in about the same place as a 5spd with a 3.08. It's not that suited to a
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HK1837		#12 Posted : Tuesday, 22 April 2008 6:45:13 AM(UTC)
Rank: Veteran Reputation: Groups: Moderator, Registered, Veteran Joined: 1/03/2005(UTC) Posts: 14,898 Thanks: 1 times Was thanked: 558 time(s) in 533 post(s)		And a valid opinion as well. I also often suggest people rebuild an aussie 4spd as an M22 and use a 2.78:1 diff rather than retrofit a 5spd. This gives you a good 1st and a 4th gear in about the same place as a 5spd with a 3.08. Its not that suited to a r
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basketcasebear		#13 Posted : Tuesday, 22 April 2008 7:10:34 AM(UTC)
Rank: Veteran Reputation: Groups: Moderator, Registered, Veteran Joined: 2/08/2006(UTC) Posts: 1,307		I wonder how my ratio,s will go?? 308,,t400,,,3.35 diff,,and 15inch 75 high tyres? cant do road tests yet,, just wondering? thanks bcb ptpro some men see things as they are, and ask "why" I dream of things that never were, and say, "bloody rippe
		more than basketcase than a bear! DOH!!!
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