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De-tuning suggestions

Wished I had you guys closer to me to get this thing dialed in. Everyone around here, doesn't know how to work on anything but a chevy. I think the biggest mistake was buying too small of a stall (2400-2800), and put a thermostat in the electric water pump. I have a 4 core radiator with large electric fan w/ shroud, which should cool. I guess the thermostat is restricting the flow too much. Easy fix to take out the thermostat. I'm open to all suggestions, in just a little over my head and don't know where to go from here.

From the description of your motor the converter sounds way too tight to me. I run a 9.5" with a stall rating of around 4500 and if anything I think it could benefit from a bit higher rating. I can't count the conversations where people think that because my converter has a 4500 stall rating that it slips to 4500
before moving the car.... Mine is locked up tight the minute its in gear.
Most electric water pumps do not have a bypass around the T stat. If you are seeing problems with your upper radiator hose collapsing thats why. It will also create overheating issues. If you don't have a bypass on the pump you will need to either run an orifice plate instead of a T stat or drill some holes in the rim of a T stat to allow for some bypass. I run an orifice plate in mine (I think .625 or .75") and have zero issues overheating in the summer. During the colder months I actually have trouble getting the motor warmed up enough..
 
I feel your pain as mine takes premium gas or else I get run-on...440- stroked over indy heads milodon bottom end///
I actually was running Hp manifolds and the noise up front was getting unbearable...too much flow for my baby. A little Smaller carb could take it down a notch too ...
 
when does the car overheat?all the time,stop and go,when driving down the free way?a single electric fan setup rarely works for a hot motor.(wont pull enough cfm)i use twin fan setup's.my current setup will pull 4800 cfm.also sounds like you could be having issues with the electric water pump on the street,but that would depend on when you are over heating. i6206.jpg
 
You're going to need a vacuum canister too if you plan on keeping your power brakes working. Personally I'd drive it and see how she behaves in traffic. Put in a converter with a higher stall speed like thumper said and run with it. Also make sure your lower radiator hose has a good spring in it to keep it from collapsing.

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Damned auto correct!!! That should have been "stumper" instead of thumper!!! Maybe it was me thinking about what your cam would sound like at idle.... My bad LOL..
 
I have a vacuum pump for the brakes, should I have a canister as well?

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I've just driven it once for a mile or so and temps got up to 240 before I got it home, just normal driving.

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I have 4 5/32" holes drilled in the thermostat housing. What stall would you suggest and why. The previous owner of this motor used a 5000 stall and a trans brake, but was strictly used it for bracket racing.

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I'll check and get back w/ the cfm's and gpm's.
 
A canister will store a little bit of "extra" vacuum sort of like an acetylene or oxygen bottle, but in reverse. It helps to keep the power brake booster working if you have to step on the brake pedal a few times in succession. A vacuum pump installed?? Can you take a picture of that and post it?? Are you running an aluminum radiator with aluminum heads too?? If so your car should have a hard time reaching 200 degrees. I would suspect the electric water pump.
 
A canister will store a little bit of "extra" vacuum sort of like an acetylene or oxygen bottle, but in reverse. It helps to keep the power brake booster working if you have to step on the brake pedal a few times in succession. A vacuum pump installed?? Can you take a picture of that and post it?? Are you running an aluminum radiator with aluminum heads too?? If so your car should have a hard time reaching 200 degrees. I would suspect the electric water pump.
Yes aluminum radiator, not sure of the accuracy of the temp gauge, but was reading 240 degrees before I got home. I've attached a link of the vacuum pump I bought for the car. http://www.ebay.com/itm/New-SSBC-El...er-Street-Rod-w-Radical-Cam-12V-/380628266673
 
I use the MP 590 camshaft with 1.6:1 rockers and aluminum heads with Victor intake and 850 DP (to little) carb..... You'll want more converter like a Dynamic 9.5" to stall (foot brake) around 4500 to get the most from it though......
I have 4.10:1 gears in mine,,,,,, might like a 4.30:1 better to get the most out of the package.
I have a bit more compression than yours too...... My pistons are domed @ .120".
I just took a nice drive in mine today..... NO PROBLEMS!!!!!
I wouldn't de-tune the engine..... just a looser converter and more gear...... (to gain the most).....

Regards
 
I use the MP 590 camshaft with 1.6:1 rockers and aluminum heads with Victor intake and 850 DP (to little) carb..... You'll want more converter like a Dynamic 9.5" to stall (foot brake) around 4500 to get the most from it though......
I have 4.10:1 gears in mine,,,,,, might like a 4.30:1 better to get the most out of the package.
I have a bit more compression than yours too...... My pistons are domed @ .120".
I just took a nice drive in mine today..... NO PROBLEMS!!!!!
I wouldn't de-tune the engine..... just a looser converter and more gear...... (to gain the most).....

Regards
From reading most of the replies, my first inclination is to check the hoses from the radiator possibly collapsing and to check the total timing. I will have to take it to someone to check the total timing because I'm not sure how to do it. I think it is obvious I will have to change to a larger stall, the question is which size is the best for my application, is there a calculator for this? Also, I would like to ask what your idle speed is for your application?
 
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