Iv'e just redone my motor (383) alumn. head bla,bla,bla. the only 2 things I changed were the cam ,and converter.The old converter was 10" 3600flash,new converter is 8" 4500flash.the cam 244-252@ .050 544-550 0n 110cl. the old cam basicly same dur ,same lift onlt on a 108cl.

NOW with the old set up @ 160-170,maybe on a hot day in trafic went to 180-190.
With the new set up, I watch the temp rise from 160 -180 -190.after driving around .I'd like it to be back @ or aroung 160 170 again .Could some one please give me aliitle help with this .If you need more info, just let me know............... Thanx

Sine everything was fine untill the head/cam change it could simply be retartded base timing causing the motor to run hotter then normal,very commong thing to happen or be overlooked.

With a 244 dur @ .05 cam in only 383 cubes you best be running a min of 18 deg base/initial timing if not 20 deg base,thats a lot of duration for a 383,must be very rough idle.

Make sure to check/set base timing with motor idling low like 650-700rpm max,over that and the mech adv in the dist cam become partially activated upsetting the base timing adj.

Look for total of 36-38 max with 18-20 base timing,if total is over 38 have the mech adv in the dist recurved for 18 max in by 2800 rpm,then 18-20 base timing + 18 deg mech in dist will = 36-38 totall in by 2800 rpm.

But dont just retartd the total timing if its over 38 deg becasue for every deg you retard the total timing the base timing is also retarded that same deg of timing.

Do it right and you will be rewarded with a crisp nice running motor.

Scott

Thanx,,, Timing is set @ 18 (black bushing in MSD) total is 36deg.This was all done with the HEAVY springs in and @ 850 rpm.........

ok,well its not that,your timing is where it belongs.

Still,180-190 is not bad at all and you may not be aware that motors run more efficent at 180-190 deg then 160-170 deg .

If your temps dont go any higher then 190-200 in traffic your good to go.

BTW,did you happed to install the temp gauge sender in a different place after the upgrade? I asj because if you moved it from intake to head it will read approx 10-15 deg higher in the head by the ex port/manifold then in the intake.

Or did you get a new gauge and this one reads higher?

Or some head gaskesy have smaller coolent passage holes then others and it that happended durring the head change without you noticing it maybe the coolent flow restriction makes it run a tad hotter but still 190 isnt bad at all.

Could it be running laen or have a sligh vac leak leaning it out some?

Or maybe the dif lsa on the cam has casuied the idle /lower speed fuel calibarion to lean out a bit resulting a leaner mixture therfor hotter engine temps.

If you suspect that and it look like that from plug readings then try going up a little more in main jet and also try adj the idle mixture a little richer to see if that lowers the temp a bit.

What cooling system are you running,an al rad or 3 /4 core stock type rad/hi output w/pump,clutch fan with std or h/d clutch?

Scott

Thanx Scott. I have a Bcool alumn. rad,Misiere (black) elect. water pump. The sender is still in the same place.I didn't think to check the carb for a lean condition.I did pull a plug, and from idleing it looked norm (moca brown.) and I tryed turning them all a 1/4 turn rich and a 1/4 leaner and it still runs better as it was set with the old cam set up.I do realize that 190 isnt all that bad, just 160-170 makes a easier cool down in on hot lapping.

The head gaskets are the same ones used in the older build ,steel shimmed GM gaskets.Again ,no problem with them and over 50-60 track runs and 15000 street miles.

Thanx for the help..............

What kind of fan shroud are you using? What kind of thermostat did you put in? Are you sure that the coolant is full?

Tell us about the radiator hoses. I have seen them collapse when rpms increase.

Steve

I don't have a shroud.I didn't before.The stat is a 160deg.(nappa)I burpped the sys. thinking it had air trapped ran a hose in the neck and let the car run,then filled it up to the bottom of the neck strait water with 2 bottles of water wetter.and still climbs up to 180-190.All the hoses are in great shape.

I'm really stumpped on this I know the temps are ok but that still does'nt explain the 20deg rise. Thanx to all who replied

Check your carb calibration to ensure its not lean on idle or at low rpm/prat throttle cruise.

But if thats allok and its running fine dont worry about it,180-190deg is just fine and 200deg in stop /go traffic would be acceptable too so your good to go.

Maybe the different /new heads & cam setup/combination just run a little hotter and there is nothing you can do about it short of installing an overly lrg rad to compensate for the new setup componants.

But as mentioned you should have a fan shroud ,could only help and maybe this new setup is less tollerant of no shroud at idle or stop/gp traffic.

But your going to end up chassing your tail arround on a problem thats not there ,i say because you seem to have everything correct and its likely eh new cam/head change that inc temp a smidge. But still chk carb for lean as i already stated. But again,the 180-190 deg temps are just right and i was wondering where your getting the idea its too high because thats wrong. The 160-170 deg the motor used to run was TOO COOL/NO AS EFFICIENT so foget about it IMHO and install a shroud.

Just my 2cents

Scott

Thanx again, I am going to re-cal. the carb,going to fatten it up 1/2 turn re-adjust idle ect and see what that does.And maybe add a shroud. Again ,thanx for the advice.

i would play with the air bleeds on the carb you will see a big difference by closing up the little holes on the high side a few sizes . and remember you add a 8 in 4500 stall that's not the most friendliest thing for street driving trans temp maybe playing a part in this . like they have said before 190 is really good for making power. also have you try ed going up 3 or 4 sizes on the main jet re son i say 3 or 4 is 2 is really for fine tuning

Again ,thanx for the replies.I have been keeping an eye on the trans temp,and did add a fan before taking the car out,and the trans temp stays 2 or around 150-170.which isn't bad from what I was told,but I thought that might have been playing a part due to the smaller converter adding more heat to the car. makes scense.

Never thought about air bleeds,very good point.Again thanx for the info .........

Again ,thanx for the replies.I have been keeping an eye on the trans temp,and did add a fan before taking the car out,and the trans temp stays 2 or around 150-170.which isn't bad from what I was told,but I thought that might have been playing a part due to the smaller converter adding more heat to the car. makes scense.

Never thought about air bleeds,very good point.Again thanx for the info .........glad to help. your good on trans temp 180 is were it should run. you can try a experiment by taking something like mig wire and inserting it in the 2 center air bleeds to restrick the bleeds some. is this a 4150 holley ? if so i would say there the same as 4500s on which the center air bleed are high speed ones and outers are idle side this is how we figured out are lean problem on my 10.5 outlaw car . if you don't have screw in type air bleeds you can epoxy them closed and re drill out the size you need you can pm if you need more info

This is on a 4150 Holly type carb,however there are only 2 bleeds per inside and outside.I'm assuming the inside ones are the high speed bleeds.

This is on a 4150 Holly type carb,however there are only 2 bleeds per inside and outside.I'm assuming the inside ones are the high speed bleeds.
correct restrict them up a little and see if that helps. :yes: