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Discussion Starter #1
I am looking for knowledge, what is a reasonable horsepower/torque number from a 350 chevy with a blower? I am considering buying a car that has this new engine in it, but has not been operated. How hard will it be to tune this beast? I would probably run safely at 4-5 psi boost? Any suggestions?
 

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Give me the compression ratio and redline of the engine as well as catagorize it for me according to the following prep levels:

Performance (avarage performance mods such as headers and free flowing pipes, mufflers and intake)

Hot Street THIS SOUNDS LIKE YOU(Mods would take the engine to a level that would be keep it streetable but OK in general for a hard-core hotrodder)

Street/Strip (this is a car that has its place on the track but a quick run on the street is possible for week-end battles and the occasional trip to work)

Mild Race (A proven bracket racer or a really wild street car)

Full Race (a full out race car running on something than normal pump gas)

These descriptions will give ma a ageneral prep level in order for me to calculate you horsepower and torque.

[email protected]

<a href="http://www.pchotrod.com" target="_blank">www.pchotrod.com</a>

I'll have a basic set of numbers for you tomorrow morning based on what you have posted so far.

Is the 5 psi boost correct? It seems sort of low.
 

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Discussion Starter #3
This is what I have been told so far on this engine, compression 10.25:1, redline 6500, boost is set at 5 psi. I have to do the wiring after purchase to get it running. I can alter the boost later after breaking in the motor, what would be an aggressive versus all out radical setting? The exhaust is headers and cherry bomb mufflers. It will be used primarily on the street, but she will see some 1/4 mile action.
2200 lbs.
Agressive Street/Strip 35 Chevy 3 Window Coupe
 

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Mite want to check the com. ratio out that seem to high for a blown motor. At most think the ratio should be 8.5 to 9 to1. What kind of Carbs is it running? Auto or Manualy trans?
 

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Running a relatively small cubic inch motor with a 6-71 blower at only 5 psi does not generate a great deal of horse power and torque.

Generally a blown motor runs low compression and high boost levels, maybe around 12 - 18 psi depending on the combination and the car's intended use.

A blower creates a great deal of parasitic drag on an engine and the only way to overcome this drag is to have a fair amount of boost.

I have a client that runs a combination that is similar to yours. It is a 1936 Chevy Truck (Pro Street) with a 355 small block and 6-71 blower at 10-12 psi. The engine make 537hp @ 6000 rpm and 530 ft/lb torque at 4200 rpm with a redline of 6500.

The performance report for the Pro Street truck can be viewed at the following location.
Look for the Peach 1936 chevy Truck and click on performance report.

<a href="http://www.pchotrod.com/Clients.htm" target="_blank">http://www.pchotrod.com/Clients.htm</a>

Keep in mind that boost is what makes a blower work for you. Most factory built blown vehicles such as the Ford Lightning only produces a max of 8 psi boost from a small Eaton blower.

Imagine what a larger blower such as your 6-71 or even an 8-71 could do for you. Top Fuel Dragster Blowers crank up as high as 24 - 28 psi of boost. That's one reason why they don't stay together very long. Send me an email and I'll return a datasheet for you to fill our with details for your car.

I can then run your numbers accuratly and email you the completed performance report.

<a href="http://www.pchotrod.com" target="_blank">www.pchotrod.com</a>
 

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Discussion Starter #6
The car has a 4 spd muncie M22 rockcrusher with a ford 9 inch rear/3.90 ratio. I am trying to determine if this car is going to be worth my time and money. I will probably buy it and sell the blown 350 if it does not produce for me. The car is almost perfect, except the motor is not what I would prefer to use.
 

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I have a number of reports for you from PC HOTROD.

I guessed at the transmission and installed a 700r4. Take a look at the configuration and let me know what you think.

I'll re run the reports with the Muncie transmission. I have some doubts about the compression ratio and blower combo though. High compression and a blower typically don't mix.

I'll email you the reports to the address listed in your profile. If the car is actually anywhere near the setup we have been discussing IT WILL ROCK!

Even if the engine only produces 440 hp it will still run in the 10's with the right tires.

Let me know what you think.

[ April 17, 2002: Message edited by: PC Hotrod ]</p>
 

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I have a number of reports for you from PC HOTROD.

I guessed at the transmission and installed a 700r4. Take a look at the configuration and let me know what you think.

I'll re run the reports with the Muncie transmission. I have some doubts about the compression ratio and blower combo though. High compression and a blower typically don't mix.

I'll email you the reports to the address listed in your profile. If the car is actually anywhere near the setup we have been discussing IT WILL ROCK!

Even if the engine only produces 440 hp it will still run in the 10's with the right tires.

Let me know what you think.

[email protected]

<a href="http://www.pchotrod.com" target="_blank">www.pchotrod.com</a>

[ April 17, 2002: Message edited by: PC Hotrod ]</p>
 

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I have a number of reports for you from PC HOTROD.

I guessed at the transmission and installed a 700r4. Take a look at the configuration and let me know what you think.

I'll re run the reports with the Muncie transmission. I have some doubts about the compression ratio and blower combo though. High compression and a blower typically don't mix.

I'll email you the reports to the address listed in your profile. If the car is actually anywhere near the setup we have been discussing IT WILL ROCK!

Even if the engine only produces 440 hp it will still run in the 10’s with the right tires.

Let me know what you think.

[email protected]

<a href="http://www.pchotrod.com" target="_blank">www.pchotrod.com</a>
 
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