How fast is too fast?
Burning Brakes
Joined: Jun 2009
Posts: 840
Likes: 4
From: Syracuse IN
What is the big deal? We run our Small block Chevy's 4,500 all day long in our boats. I mean for hrs 6 to 8 when we run North and South of Lake Michigan. Hi Rpm's are not a problem, lugging the engine is. Al
Team Owner
Joined: Jan 2007
Posts: 53,648
Likes: 878
From: Southern Cal Ca
St. Jude Donor '22
what is the TBO on a marinized 350?
1000hr, 65,000 miles?
heat, marinized run what, 160? 180 with closed system?
vs 210 in a car.
forged internals and stout crank vs cast 2 bolt
cam slightly different.
Drifting
Joined: Mar 2011
Posts: 1,347
Likes: 121
From: Kernersville NC
Yes, we have, but you make that sound like a bad thing. 
I share the OP's concerns.
I like the idea that OD can reduce:
1. Wear and tear on the mill.
2. Noise. (I like headers & pipes--I don't like D-R-O-N-E, for 6 hours, one way).
3. Gas consumption.
I've seen mention of both Tremac and Richmond trannies, in both 5 and 6 speeds. I like to shift, so I'd like a 6 speed.
My Questions:
1. Cost of Tremac 5spd conversion? 6spd? (Parts only--my labor).
2. Cost of Richmond 5spd conversion? 6spd? (Parts only--my labor).
3. What 5spd is in early '80's Z28's? I read (here) it was a Tremac, and that buying a rusted out Z28 for hundreds of dollars would be, by far, the cheapest conversion. Discuss?
4. When doing these conversions, are new cross members available? And I'm guessing I get to drill new holes? Or are the cross members engineered to use the existing holes in the frame.
Thank you.
I share the OP's concerns.
I like the idea that OD can reduce:
1. Wear and tear on the mill.
2. Noise. (I like headers & pipes--I don't like D-R-O-N-E, for 6 hours, one way).
3. Gas consumption.
I've seen mention of both Tremac and Richmond trannies, in both 5 and 6 speeds. I like to shift, so I'd like a 6 speed.
My Questions:
1. Cost of Tremac 5spd conversion? 6spd? (Parts only--my labor).
2. Cost of Richmond 5spd conversion? 6spd? (Parts only--my labor).
3. What 5spd is in early '80's Z28's? I read (here) it was a Tremac, and that buying a rusted out Z28 for hundreds of dollars would be, by far, the cheapest conversion. Discuss?
4. When doing these conversions, are new cross members available? And I'm guessing I get to drill new holes? Or are the cross members engineered to use the existing holes in the frame.
Thank you.
The kit comes with a bracket to mount trans to the crossmember. I drilled no new holes.
Best money I have spent on the car by far. We take it on day trips to the mountains now as much as the C5.
Burning Brakes
Joined: Jun 2009
Posts: 840
Likes: 4
From: Syracuse IN
Actually we are seeing well over 2,000 hrs on engines, and true temps are usually around 180 to 195 on closed systems. Yes the cams are slightly differant, specifically the Exhaust timing.. Most are upwards of the 300 hp mark. Are you saying marine engines are better than auto??? Better than our prized C3's. Don't say it so Joe. Oh ya, current production blocks are much better than our antiquated C3 blocks/rotating assy;s Al
Instructor
Joined: Feb 2013
Posts: 197
Likes: 0
Thank You....
Tremec TKO600 .64OD and new Centerforce DF clutch, machined flywheel cost me about $3600 with my labor. I had a cracked bellhousing so I bought a new one. That is not included in the above figure. I also wanted to cut the crossmember and I paid to have a little welding done.
The kit comes with a bracket to mount trans to the crossmember. I drilled no new holes.
Best money I have spent on the car by far. We take it on day trips to the mountains now as much as the C5.
The kit comes with a bracket to mount trans to the crossmember. I drilled no new holes.
Best money I have spent on the car by far. We take it on day trips to the mountains now as much as the C5.
Thank you, very much, for the mechanical and financial breakdown of your conversion.
And I'm really pleased to hear how satisfied you are with it--I would be too!
Now I must reveal my ignorance (which gets easier with repetition
): Is your TKO a 6-speed or a 5-speed? I did some Googling and all I could find were sales pitches, but no specs.And did your gasoline consumption change noticeably?
Thanks again.
Peter
Safety Car
Joined: Jan 2009
Posts: 4,000
Likes: 299
From: New York
All this talk they where built for it ... LMAO .... They where built with available parts of the day and most cars back then did not see 100,000 miles before serious work was done to them.
Get into a newer computer controlled car and if you don't get 200,000 miles out of them your doing something wrong.
Put an O/D in it OP and you will be a lot happier and so will your car.
Get into a newer computer controlled car and if you don't get 200,000 miles out of them your doing something wrong.
Put an O/D in it OP and you will be a lot happier and so will your car.
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Le Mans Master
Joined: Nov 2006
Posts: 7,215
Likes: 1
From: Orlando FL
All this talk they where built for it ... LMAO .... They where built with available parts of the day and most cars back then did not see 100,000 miles before serious work was done to them.
Get into a newer computer controlled car and if you don't get 200,000 miles out of them your doing something wrong.
Put an O/D in it OP and you will be a lot happier and so will your car.
Get into a newer computer controlled car and if you don't get 200,000 miles out of them your doing something wrong.
Put an O/D in it OP and you will be a lot happier and so will your car.
not sure where you were in the "DAY" but oil had zinc in it and if you changed it every 3K, things were good. We had a 69 chevy truck at my uncles shop with BBC and it ran about 300K before we tore it down for an overhaul.
Safety Car
Joined: Jan 2009
Posts: 4,000
Likes: 299
From: New York
Usually these old motors where lucky to see 100k with out serious work and those who want to chime in I had one or I knew of one are just exceptions to the reality of that time period.
So my "Day" spent in a transmission business allows me to have first hand experience , lets not forget why people ask the buyer of a used car how many miles on her ,,, that came about from back in the "day" where now a 150k is considered a lot but we expect she will give up 50k or more before an overhaul.
Melting Slicks
Joined: Sep 2010
Posts: 2,383
Likes: 59
From: Emerald Isle NC
Yes, we have, but you make that sound like a bad thing.
I share the OP's concerns.
I like the idea that OD can reduce:
1. Wear and tear on the mill.
2. Noise. (I like headers & pipes--I don't like D-R-O-N-E, for 6 hours, one way).
3. Gas consumption.
I've seen mention of both Tremac and Richmond trannies, in both 5 and 6 speeds. I like to shift, so I'd like a 6 speed.
My Questions:
1. Cost of Tremac 5spd conversion? 6spd? (Parts only--my labor).
2. Cost of Richmond 5spd conversion? 6spd? (Parts only--my labor).
3. What 5spd is in early '80's Z28's? I read (here) it was a Tremac, and that buying a rusted out Z28 for hundreds of dollars would be, by far, the cheapest conversion. Discuss?
4. When doing these conversions, are new cross members available? And I'm guessing I get to drill new holes? Or are the cross members engineered to use the existing holes in the frame.
Thank you.
I share the OP's concerns.
I like the idea that OD can reduce:
1. Wear and tear on the mill.
2. Noise. (I like headers & pipes--I don't like D-R-O-N-E, for 6 hours, one way).
3. Gas consumption.
I've seen mention of both Tremac and Richmond trannies, in both 5 and 6 speeds. I like to shift, so I'd like a 6 speed.
My Questions:
1. Cost of Tremac 5spd conversion? 6spd? (Parts only--my labor).
2. Cost of Richmond 5spd conversion? 6spd? (Parts only--my labor).
3. What 5spd is in early '80's Z28's? I read (here) it was a Tremac, and that buying a rusted out Z28 for hundreds of dollars would be, by far, the cheapest conversion. Discuss?
4. When doing these conversions, are new cross members available? And I'm guessing I get to drill new holes? Or are the cross members engineered to use the existing holes in the frame.
Thank you.
My car has a TKO-600 and 3.70 rear. TKO-600 is well suited to the 3.70 rear. Years ago, before these conversions were common, we would sit around and talk about how this would be perhaps the greatest thing you could do to old cars. By years ago, I mean late '80s,
which was also the last time I owned a car without OD.
The switch was one of the first things I planned to do to my car when I bought it. I'll never go back to the slushbox, but will keep it anyhow.
Again, not a bad, but very good thing!
Carter
Terrorizing Orange Cones
Joined: Oct 2007
Posts: 2,572
Likes: 17
From: Northern CO
Made my project more enjoyable in today's economy and technology-infused environment.
The h311 of it is, back then, 101 octane leaded gas was only 33 cents a gallon and available everywhere... 
Instructor
Joined: Mar 2013
Posts: 100
Likes: 0
I am gettin 2,700 rpm at 70mph and was nervous running like that for 20-30 minutes. Did a search to see how scared I should be, and now I know it's not a huge deal. I want to switch to a OD tranny but don't have the pockets for one yet.
Melting Slicks
Joined: Mar 2007
Posts: 2,520
Likes: 11
From: Hinckley OH
Just for the heck of it I crunched a few numbers about the cost of converting to overdrive vs paying for the gas.
I assumed 15 MPG without OD and 20 MPG with OD with gasoline costing 3.75 per gallon.
I also assumed it cost $2500 to install the OD. Based on those assumptions it would take 30,000 miles of highway driving to save the cost of the installation in gas.
I saved the spreadsheet to do the calculations so if somebody has more realistic numbers to plug in I can do the math ... for a few.
I assumed 15 MPG without OD and 20 MPG with OD with gasoline costing 3.75 per gallon.
I also assumed it cost $2500 to install the OD. Based on those assumptions it would take 30,000 miles of highway driving to save the cost of the installation in gas.
I saved the spreadsheet to do the calculations so if somebody has more realistic numbers to plug in I can do the math ... for a few.
