tbi intake question
 

so i have a 1987 gmc v3500 with a tbi 454. it came stock with the carb intake with the gm spacer to make the tbi fit. this spacer has coolant running through it. i just got the edelbrock performer tbi intake for it, and it has the same provisions for the coolant to run into the intake just below the tbi. my question is, what is the purpose to have coolant running through the intake in this area? it seems to me that it would not help performance because it would heat up the air, and i thought a cooler, more dense air fuel mixture was better. any ides on wheather or not this is needed? i cant see any reason, except maybe on cold startup, i was planning on just plugging the coolant passage through the tbi base area off and routing the coolant like a carb 454 would have it. any info would be great, thanks in advance!

Re: tbi intake question
 

For cold weather operation to keep the intake from icing up as I understand.

Re: tbi intake question
 

For 87 to 90 BBC TBI GM used a stock pile of cast iron (CI) Q-jet intakes with the well known plumber delight adapter plate. For 91 to 95 GM switched to aluminum intake. Aluminum heats up faster and it was a dedicated intake for Gen 5 BBC. Rumor has it that GM had a stockpile of Q-jet intakes and when they could not emission certify BBC with a carb for 87+ models they went with a bigger TBI on top of Q-jet intake.

//RF

Re: tbi intake question
 

maybe i have you confused, i understand the cold weather idea behind the coolant running below the tbi (thanks Ziegelsteinfaust) but what i'm wondering is, cold weather aside, would it be possible to plug this coolant passage and just plumb the coolant like like it is on a carb intake?

Re: tbi intake question
 

I plugged all that junk on my 88 model 454. My heater hoses are now run just like traditional engines always did. No problems that I can tell.
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Re: tbi intake question
 

I bypassed the baseplate on my tbi 454. No problems at all when it is cold out. I also opened up the air cleaner so it is now a 5" tall open element filter, still no freeze up problems and it has been that way for 2 years now.

Re: tbi intake question
 

thanks guys! thats the answer i was looking for, thats probably what im gunna do now too! thanks again!