MCfan Posted August 4, 2014 Share Posted August 4, 2014 I know what you mean with the RPM. My 71 454 does 3200 at 70 also. I'll be listening to that big block howling for 500 miles in 2 days. Ouch ... hope you don't have to cross any uninhabited deserts. Just curious, Aaron, what size rear tire and what differential ratio gives you that result? I know some SS cars had 3.31 rear gears but most seem to have 2.56. Even so, the 3.31 rear and a 28" tall tire (275/60) gives exactly 40 rpm per each mph (2800 rpm @ 70 mph) in high gear (1:1) of my 4 speed car. Maybe you're running a 3.73 or a 3.31 with a shorter tire or maybe the TH400 doesn't lock up in a 1:1 high gear at cruising speed? I've noticed that the 2.56 in my '70 SS delivers speedometer readings that equate more to a 3.08 on paper, possibly due to TH400 slippage. Quote Link to comment Share on other sites More sharing options...
badddoin Posted August 5, 2014 Share Posted August 5, 2014 My 4.10 with 28 inch tire is real close to 50 RPM/MPH. At 3000 RPM I'm going 'bout 59 MPH, according to the GPS. Loves gasoline, too. Quote Link to comment Share on other sites More sharing options...
monte70car Posted August 5, 2014 Share Posted August 5, 2014 I open the roll up door to the home of my 70 It's parked in a 10'x17' portable garage from Harbor Fright kinda wish it was bigger but couldn't pass up the deal. Quote Link to comment Share on other sites More sharing options...
Canuck Posted August 5, 2014 Author Share Posted August 5, 2014 Originally Posted By: Canuck I know what you mean with the RPM. My 71 454 does 3200 at 70 also. I'll be listening to that big block howling for 500 miles in 2 days. Ouch ... hope you don't have to cross any uninhabited deserts. Just curious, Aaron, what size rear tire and what differential ratio gives you that result? I know some SS cars had 3.31 rear gears but most seem to have 2.56. Even so, the 3.31 rear and a 28" tall tire (275/60) gives exactly 40 rpm per each mph (2800 rpm @ 70 mph) in high gear (1:1) of my 4 speed car. Maybe you're running a 3.73 or a 3.31 with a shorter tire or maybe the TH400 doesn't lock up in a 1:1 high gear at cruising speed? I've noticed that the 2.56 in my '70 SS delivers speedometer readings that equate more to a 3.08 on paper, possibly due to TH400 slippage. My car came with the optional 3.31 rear gear and I currently have 245/60/15 tires. Using an online calculator I found, I should be at 2,930 RPM at 70 MPH. I wonder if I actually have 3.55s in my car? Quote Link to comment Share on other sites More sharing options...
Canuck Posted August 5, 2014 Author Share Posted August 5, 2014 I took the 71 out for a drive. At 60 MPH with 26.57 inch diameter tires I'm doing 2,800 RPM. At 70 MPH I'm doing 3,300 RPM. If my tach and speedo are reading correctly, that would mean I have 3.73 gears possibly? I'm averaging about 12.5 MPG (US gallons) but many of those miles are highway. Quote Link to comment Share on other sites More sharing options...
Ian Posted August 5, 2014 Share Posted August 5, 2014 Mine has 245 60 15 BFG's, 3.42 gears and the TH400. By the GPS at 70 the tach says 3200rpm Quote Link to comment Share on other sites More sharing options...
Canuck Posted August 6, 2014 Author Share Posted August 6, 2014 Washed up the 71, checked fluids and finished packing the car. All ready to go to the Western Meet. Quote Link to comment Share on other sites More sharing options...
Leghome Posted August 6, 2014 Share Posted August 6, 2014 I have 255 60's 15 and 373 gears and at 70MPH my 350CI and 700R4 is turning 2750RPM's Quote Link to comment Share on other sites More sharing options...
Patrick Sheean Posted August 7, 2014 Share Posted August 7, 2014 Monte is getting his tranny rebuilt, no more kitty litter on the garage floor. Quote Link to comment Share on other sites More sharing options...
Hisalone Posted August 8, 2014 Share Posted August 8, 2014 Noticed my paint chipping on my hood props so I decided to plasti dip them. Durable material and softer in case my kid drags it against the paint like he's already done when trying to help prop up the hood. You like my contraption to suspend them? Wife was not too pleased I used her laundry rack. Lol Also, the paint began peeling on the master cylinder so I used engine enamel just in case it's the heat causing the issue. I suspect since it is peeling in the spot thats closest to the heat coming off the engine. Quote Link to comment Share on other sites More sharing options...
LostnFound Posted August 8, 2014 Share Posted August 8, 2014 That's the ONLY good use for a laundry rack I.M.O. Drove mine to a cruise night tonight.....300 cars in attendance with lots of spectators too. Mine was the only Monte Carlo. I had lot's of nice comments on the car and lot's of people asking questions and some said they had never seen a FGMC SS before. I just finished cleaning the bugs off and parked her back in the garage. Quote Link to comment Share on other sites More sharing options...
7tonemonte Posted August 8, 2014 Share Posted August 8, 2014 Drove mine to work today and the local Sonic for a cruise night! I did see another 71 there, he was having a hard time finding a parking spot and left before I got to talk to him. Real nice looking triple black too. The kids got to sit in the chairs behind mine and eat ice cream, and I got to talk to quite a few people, very fun night for a change! I really needed it! And Larry,Mi feel your pain on the bugs, mine will have to wait till tomorrow Quote Link to comment Share on other sites More sharing options...
72jrfan88 Posted August 8, 2014 Share Posted August 8, 2014 That's the ONLY good use for a laundry rack f gmc. O. Drove mine to a cruise night tonight.....300 cars in attendance with lots of spectators too. Mine was the only Monte Carlo. I had lot's of nice comments on the car and lot's of people asking questions and some said they had never seen a FGMC SS before. I just finished cleaning the bugs off and parked her back in the garage. I also just got back from a cruise night. I was also the only fgmc there were two 87 ss. I also got alot of questions/ compliments. One gentleman however swears custom on my sail panel is "something only buick made, so that cant be right" Quote Link to comment Share on other sites More sharing options...
LostnFound Posted August 8, 2014 Share Posted August 8, 2014 I also just got back from a cruise night. I was also the only fgmc there were two 87 ss. I also got alot of questions/ compliments. One gentleman however swears custom on my sail panel is "something only buick made, so that cant be right" There's lots of misconceptions and misinformation out there about these cars for sure. Quote Link to comment Share on other sites More sharing options...
502ci Posted August 8, 2014 Share Posted August 8, 2014 Removed my MSD Digital 6 Plus ignition from my Monte and sent it in for repair...probably won't get the part back 3 weeks from today... Quote Link to comment Share on other sites More sharing options...
Boots Posted August 8, 2014 Share Posted August 8, 2014 Well I didn't do anything TO my car but FOR it. went to the wreckers and picked up a 4l80e, both yokes and drive-shaft to be "refreshed over the winter...guess I will have to plow a little more Quote Link to comment Share on other sites More sharing options...
Hisalone Posted August 8, 2014 Share Posted August 8, 2014 A lot of cruise nights tonight apparently. Glad I stayed in and worked since a rain storm popped up and probably washed away the two popular local cruise spots on Thursdays. Quote Link to comment Share on other sites More sharing options...
cbolt Posted August 8, 2014 Share Posted August 8, 2014 Ordered a rear bumper from Rock Auto, we will see what I get. Took the intake and rear bumper brackets to the powder coat shop. Dyed the gauge pod to match the interior color and mounted gauges. Finished the booster and proportioning valve install. I guess I should have painted the master cylinder based on the previous posts. Received the Eagle rotating assembly and got the crank shaft ready to install with the flexplate and gear. On to installing the pistons! Quote Link to comment Share on other sites More sharing options...
monte70car Posted August 9, 2014 Share Posted August 9, 2014 We rolled the frame back under the frame today noticed there is some tire rub on the tub which wasn't there before, and the body needs to go back at least an 1". Quote Link to comment Share on other sites More sharing options...
Outrider70 Posted August 9, 2014 Share Posted August 9, 2014 Drove it to work this morning! This is after yanking the tranny and replacing the input and output seals because it was hemorrhaging trans fluid and looked like I was fogging for skeeters! I still need to replace the header gaskets, fix lights, put the hood on, install a/c, paint, suspension upgrades, bigger wheels, Vette brakes....jeez, I need to win the lottery Quote Link to comment Share on other sites More sharing options...
monte70car Posted August 10, 2014 Share Posted August 10, 2014 Looking more and more like a car. looks nice from the rear as well still thinking stock rear trim or make trim for it. Quote Link to comment Share on other sites More sharing options...
LS5 Posted August 10, 2014 Share Posted August 10, 2014 Holy Schnikeys Rob those tires are a Tad bit wider than stock I believe...!!!!! hahahahaha Darren. Quote Link to comment Share on other sites More sharing options...
502ci Posted August 10, 2014 Share Posted August 10, 2014 Hey Rob, I'm thinking you need a bigger exhaust diameter. I know you mentioned you were gonna put those SS tips on it but I'm not sure they will even look big next to those huge tires. Quote Link to comment Share on other sites More sharing options...
72MC Posted August 11, 2014 Share Posted August 11, 2014 Took the plates off her yesterday. Watched her leave for her new home today. Hope she likes Long Island. - Dave Dan and Mike securing her to the trailer. And,... watching her leave. Goodbye ole friend. Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted August 11, 2014 Share Posted August 11, 2014 that last one hurts to look at Quote Link to comment Share on other sites More sharing options...
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