I had my new 396 combo on the chassis dyno over the weekend and have a few problems.


The distribitor keep moving on every run, even when we reset the timing and cranked the hold down tight it would physically move at 4500rpm ... I have a MiniRam II with stock 88 distributor and CSI billet hold down.


The other problem was with cooling, the coolant guage was at 250, the head temp was measured about the same, but the rad was only 112. I'm using an Edelbrock hi-flow water pump and 160 degree thermostat. I also had the rad cleaned before I installed the new motor. Do I need a 180 degree thermostat or should I drill holes in my 160? What should I do? HELP!!!

 

Did you use the shorter Thermostat so that it does not bottom out in the housing when it opens up?

 

I used a Mr Gasket thermostat ... does anyone know if this one bottoms out in the housing when open?

Anyone experience any problems with their distributor moving with the MiniRam intake?

 

On the dist. -After setting the timing and supposedly tighten down - can you turn the dist by hand. I dont fully snug my dist down. I mean with 2 hands I can adjust.- My preference. I am also running a MR. Are you sure the Dist gear is not worn??? Positive the cap is moving some?

On the temp side. What temps have you ran before? On my last cam change. I noticed I ran hotter than norm. 200-210. I never have been over 200 with a 160 tstat and my other setups. I went through everything. replace t-stat. even check it in a pot of boiling water. removed water pump and inspected. though it was failing. It turns out I had a air pocket in the system. I drove around for a year like this. not good. I have performed the fill process many times. even after removing the water pump it was still running hotter than normal. I finally really took care into purging out the system. I filled the radiator 3/4 the nlet the car warm until the t-stat opened and had water flowing completely through the radiator. then topped off. I was back running 180 driving and 190 idleing.
Just a idea to try.
Dennis

 

When I had my machine work done the guy told me that I would need a shim under my dist. cause the block was decked which ment that the heads sat lower and the intake had to also be cut down to fit the heads. He said the Dist. would bottom out in the block if I didn't put the shim in. I also have a Mini Ram on my motor and have no probs. JUST A THOUGHT GOOD LUCK

 

If the block is decked the distributor can bottom out on the oil pump, you'll have to shim it up or get another dist. with an adjustable collar.

I run the 160 stat on my MRII and never had any cooling issues. But I did drill the stat with a couple of 1/8" hole to help in 'burping' the system.

Good luck, Dave

 

check out my web page,
there is a link to installing miniram things to do.
it shows the difference in thermostat heights, one style works the other won't open.
mine is a miniram II.
you may need to shim the distributor as others have stated, it could be distributor gear wear too, I had to switch to a melanized gear. don't use the aftermarket brass gear, they are for racing only and won't last long at all.

 

I'm going to check the thermostat to see if it bottoms out. Should I drill a couple holes in the 160 or should I go to a 180?

Does anyone have more info on the distributor problem? I'm using a bronze gear because I'm using a billet cam. Anyone else had to shim the distributor when using a Miniram II ?

 

No problem here.

 

On my first pass I drilled a pair of .125 holes in the 160 stat and the car would not get up to temp in cool weather.

I would say one .100" hole would do, but remember I do have an aftermarket radiator too. Righ now I have one .100 hole.

My heads were milled to .68 CC and my block was decked too .010 in the hole, and I have had no distributor hold down clamp issues.

 

on the distributor, I'd pull it out and then take off the gasket, then drop it back in and see if it goes all the way down without the gasket.. If it does and isn't standing off the intake then your not bottoming out on the oil pump shaft.
If it isn't going all the way down then you'll know that some shiming is required.
while the distributor is out check the wear marks on the gear (see if its showing extreme wear or wearing towards top or bottom) it should be close to the middle of the gear.
also check to see that the shaft turns freely in the distributor (maybe the bushings are galled?
there should also be some free play up and down on the ditributor shaft (this allows for the distributor to grow when hot) I think it should be .023"- .032" alittle more shouldn't hurt anything but if its under say .018" then it may be binding once its hot.
one other thing would be to check for excessive side to side play in the bushings, its possible that a very loose bushing could allow the rotor (or something else) to come in contact and try to turn the base (normally the top bushing goes out first).
if all that checks out good then the hold down clamp must be the problem, maybe too long a bolt? bottoming out before actually clamping the distributor?
RJ

 

Anybody know the part number for the thermostat that fits the miniram?