[Diy_efi] Intake Manifold choices SBC carb to TBI conversion

[Torbjörn Forsman]

I don't think you will have any problems due to heat spreading to the 
intake manifold. The manifold's temperature will be determined by the 
cooling water, as it has water circulation for preheating. Also, the 
evaporation of the fuel helps cool down the manifold.

I recommend that you use EGR if the TBI calibration you decide to use 
originates from an engine with EGR. Some GM engines (at least the OHC 
4-cylinder engines found in european GM cars from mid- and late 80's) 
are known to run with so early ignition timing that they have a tendence 
to knock if the EGR is not working. In particular, this does matter if 
your TBI system does not have a knock sensor.

Best regards

Torbj?rn Forsman

Mike wrote:
> Hi,
> 
>  
> 
> Well I finally decided the carb must go and be replaced. Time to convert my 350 chev from a 4bbl carb to TBI
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> I'm thinking of using a stock GM TBI intake 87-91 on my 83 Chev, I will have to modify the two bolt holes to make it fit, but it will have stock locations for coolant temp etc and hopefully it will be a neater looking installation.
> 
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> 
> My only concern is heat on the TBI intake which I believe is cast aluminum, this motor is in a motorhome it doesn't over heat but it still gets pretty hot climbing hills in a 10,500LB G series van chassis.
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> Anyone had any problems with alum intakes because of heat in there motorhomes or tow vehicles
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> I would like to use a stock TBI intake with or without spacer or an edelbrock TBI intake, instead of the cast iron QJet manifold with an adapter plate.
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> The vehicle isn't required to have emissions testing and didn't have an EGR valve from the factory.  I may run an EGR valve but haven't decided yet.
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> Any info or experiences would be appreciated.
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>  
> 
> Mike. 
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