Thread: need help guys!!!!!!!!!!

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well talked with pat, got some good thoughts.
well up date.... filled the car with 87 octane, had been using 93 octane, didn't really know the c.r. figured it is 9.0 to as low as 8.5,
( pat thought if it is only 8.5 that the 93 octane could be causing some of the problems, that the low compression enignes don't like the slow burn fuel.)
still have the gutted stat in it, won't be able to get one until tommorrow.
the temp has drop to 80, wnet for a drive for 19 miles temp never got above 185, until a stopped in my drive to open the garage went up to 190.
so I don't know if the gas did anything, or if it was becuase of the lower outside temp??? any thoughts
(drove on the highway @60mph, eariler today with 93 octane 90 temp the car got to 225 same drive)

I would think the higher the octane, the slower the burn, so the more fuel you waste if you don't have enough compression to burn it. The more you waste, the richer the cylinder. The richer, the cooler. Lean = HOT, and rich is cool. I love being wrong though, I can learn something that way. Looking forward to hearing your report after more time behind the wheel. It's definately worth a try.

well will i am ok if i am wrong with it .if any thing gas will be cheaper if you do not need 93 .as for more fuel = rich = cooler engine that really never pan out for me on the blower engine i block up the power rods in the carbs to run rich thinking it would run cooler .well never did .we had are eyes burning and still ran hot. for the engine it very well could be lower then 8.5 as well ? the only thing as i can say is i never try to run a low cr engine on super pump fuel or race fuel with out a power adder

tell us every thing you know about the engine head casting numbers . cam

well with the 86 watch your timming so see it it pings do the stat 180 and see what that will do but like i said you need to try some things with the 86 you may want a 160 stat the lower fuel will not like hi heat if your at the broder line on CR but?? i do not know were your at if 7.8 and a cam on a 110 with some dur could be some problems here . ?????????????? but my brain cell are dead

Originally Posted by pat mccarthy

well with the 86 watch your timming so see it it pings do the stat 180 and see what that will do but like i said you need to try some things with the 86 you may want a 160 stat the lower fuel will not like hi heat if your at the broder line on CR but?? i do not know were your at . you should do a compession check and that will help some with were you are for CR that would help with knowing the fuel octane you need . and if 7.8 and a cam on a 110 with some dur could be some problems here . as for rich or lean by how slow the fuel burns .if the fuel is not brunt at the rigth time and still burning in the ex they seam to run hot this way . ?????????????? but my brain cell are dead

yes pat,
I know the gas can't be the only issue, but it was the only one I was able to do after I talk with you. will be changing the stat on monday, & lower the crank timing to 12 if if starts pinging.I did notice that the header and fenders were very noticably cooler than they have been in the past after driving.
the block casting year was 1974, the heads the same, not the peanut heads, wikk give # tommorrow. I will check the compression also. the reason I think the engine is probably a lower cr, less than 9.0 cr it was in a 1974 1-ton truck with a cargo box, truck ran fine temp, it actually ran on the lowside (190) & it had always ben drivin on the lowest octane gas in the truck. it also got me thinking, until earlier this spring when I drove it one day, it started diesaling (run -on) when I turn off the car, so I went put the 93 octane( highest grade) in it and it stopped. i strated to use the highest grade from the point. that one time, was the only time it had ever tried running-on when I turn off the car. never did try lowe grade since.
now for the only changes i did to the motor while it was on the engine stand was,.... installed a old holley street dominator intake, swapped the quadjet, for a new holley 750 vac secondarys, replaced the factory long nose water pump for a short-weiland hi-flow pump.
in the truck it had a acc. trans cooler, & a oil cooler which I didn;t put either in the car.(using the trans. cooler in the rad.) the oil pan is a factory 6qt. pan & i have a 1 quart oil filter on it(7 qts. total). also the radiator is different than what was in the truck. I am guessing they ever rebuilt at one time they would have built it back to '74 chevy truck or car spec, both at that point in time had low CR (8.7) but do not know for a fact, just can't see why any one would have built a high cr in a work truck. the only reson I think it was rebuilt in the last 5 yearsm, when I took off the intake exhuast manifolds the inside the engine was super clean, no sluge or gunk , & the exhaust ports & valves had no build-up at all on them, which I can't believe a non -rebuilt 35 year old would have.

the factory 1974 engine specs. all '74 engine & later 70's the had 8.2 cr !

well all i can say is they make a 454 dish and flat tops i show and that one is 7.8cr with a 119cc chamber head and a 8.2 cr with a 119 cc heads ? i do not have my stock piston book here its at the shop to see were a dish would be for cr look at it later on today

still with no stat, 87 octane gas, drove my son to preshcool, drove auto parts store & picked up a 180 & 195 high flow stats. the car went 22 miles, mostly at 60 mph, some stop & go, a/c set on med. the car ran 185 @ 60mph, in town got to 195-200, but when I got make on the road at 60 dropped back to 185, I when turn the a/c off, cranked the heat to high, within 5 min dropped to 175. turned the heat off, a/c back on went back to 185! the outside temp was 77 degrees. could the ambiant temp be whats making the improvment right now?could it be making that much difference??, the headers are definatily alot cooler with the lower octane gas.
I think I will try the 195 stat first,to see if holding the water in the rad. longer will keep it cooler, if not will try the 180. what do you guys think???

will post block info alittle later

well put in a high flow 195 stat, the temp outside is 85 now, drove for 19 mile @ 60mph, the temp got to 195 opened drop 2-4 degree closed again, finally did open but temp never got to 200. I know I need to drive it more & get it out on the interstate to run it at 70mph to really know. but the car has never run that cool when the temp was in the 80's. used a laser temp gun the headers are running 100 degrees cooler than in the past. I would never believe that the gas octane could change the temp. that much. if this didn't fix it . I will next swap out the dizzy and put one with a vacuum advance.

3:00pm outside temp 89, went to pick my son up, drove the the a/c on this time on high all the way there the car ran 195-200. but asSOON AS ` i STOPPED THE TEMP JUMPED UP TO 210 within 30 sec. shut the car off, went in to get son, came back out in 5 min. the engine was back down to 175 when I fired it up. drove home (12miles) car ran 195-200. at 60mph (2100rpms). don't think it should be jumping up 10 degrees so fast at idle??????? .
pat, the water pump pulley is 6.6" dia.
well what do you guys think? should I swap out the dist for one with vac. adv., or change something on the water pump? or do most bbc heat up that much at a stop after running at 200 degrees down the road 4 awhile?
I do think their is a big improvement with the gas change thought.
should I swap out the 195 stat for the 180??? ( don't see what that would change at idle thought)

just try the 180 stat for the hell of it .i think you can go back to the 195 if you want as for the dizzy or pump or any thing .just stay with the stat and get that nail down to the one that works the best for you then move on from there. if your looking for more .when my cars turn off they allway jump up .and when turned back on are cooler

just to let you know i did look up the dish piston for a 454 .in the federal mogul piston book ....7.491 with a 119 chamber head they show it for 70-76 cars 79thru 90 trk they show the flat top as well 73thru83 hard to say if it was rebuilt what it has but if that low i am buying the fuel did help

well I'm going to try and find a someone who has a bbc distribitor with a vac advance , that I can borrow, for a day to see if adding vacuum advance will help cool it cool it down more & to rule out, that the car isn't getting enough timing since my comp 9000 has no vacuum advance.