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Throttle Body Bypass question

D

DWC

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I just completed bypassing the throttle body of my 1996. It was an easy procedure. I am wondering if anyone has had any problems with their car after bypassing. I know that the design was to flow coolant through the throttle body in order to prevent icing or freezing of the throttle body in cold weather. I live in Kansas City, Missouri where we get some bitter cold during the winter. I usually limit my driving during that season and garage the car year round.

Has anyone in the midwest or upper midwest done this bypass then regreted it?
 
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I have read tests done on it, and when the engine is warmed up, the throttle body still runs at over 100 degrees... the coolant line heats it up to over 200... from what i understand the idea was highway driving, where there is a lot of cool air flow, and no throttle movement, ice could freeze the position of the blades, causing an accident... I have heard of people doing it up north with no ill effects (probably because it runs so hot anyway, and you have to keep your foot perfectly still for a long time... even cruise control moves the throttle almost constantly)
 

Edmond

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You could always reverse the procedure for the winter right?

What kind of gains do you usually get from doing the bypass?
 
Joined
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none right now :(
Gains are quite impressive for only a few bucks...

It all depends on the temperature of the engine... benefits are greater on LT1/4 cars than L98... but LT1/4 cars, when warmed up, figure 3 HP... (I have seen higher, even 8 HP, but it isn't very probable)
 
8

88canadianvette

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throttle body bypass

can it be done on a 88" L98? if so any benifits?
 

Ken

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Yes, it can be done, and you don't need to purchase one of those kits they advertise in the Corvette catalogs--way to much money. Just go to your local hardware store and get one of those kits for repairing garden hoses, or just a piece of pipe that fits in the hose. You can then connect the two hoses together to bypass the throttle body. You have the option of capping the openings in the TB with some caps you can find at the same hardware store, or you can simply leave them open--it ain't gonna hurt anything.

As for the benefits of doing this, a nice one is the fact that you will be able to place your hand on the TB after you bypass it, proof enough that the incoming air charge should be a degree or so cooler. It may not be much, but anything you can do to lower the intake air charge (and fuel too) is a benefit to performance.

The only drawback would be if you planned on operating the vehicle in a cold climate. The throttle body has coolant flowing through it to prevent icing of the throttle blades.

Good luck.

_ken :w
 

WhalePirot

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No diff noticed

I bypassed mine with two hose clamps and a piece of leftover copper pipe

I feel no difference whatsoever.

:w
 
D

donhall

Guest
whalePirot has got it dead right. The only benefit from a TB by-pass is the removal of two hoses from the engine bay, if you replace the tee fittings with in-line pipe. If you were to dyno this mod, before and after, you will not see one HP increase. Air passes through the TB in milliseconds, and the heat absorbtion is miniscule. If you want cooler air introduced to your combustion system, add a nitrous bottle. I would venture to say that the TB by-pass has destroyed numerous optisparks due to the owners, when performing this "mod", not draining the coolant from the top of the engine, and allowing it to spill onto the optispark. Use the twenty minutes that would have been expended on the TB by-pass procedure, by applying another coat of wax.
 

vms4evr

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Durham, NC
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Well here is a link to someone who did this on an LT1 and did dyno runs before and after. His dyno run says it does work. And it is not the only one I've seen that shows an improvement. Check out some of his other parts swaps and resulting dyno runs. Pretty good website.

http://ws6.com/mod-8.htm

Graham
 
S

Springer's LT4

Guest
This isn't a mod that gives you noticable HP the minute you do it... its one of those small things that add up with doing other small things.

One benifit of doing it is now you have a completly dry intake and can yank the intake off without having to touch the cooling. Another is the electronics that are attached to the TB will live longer with less heat.

I bypassed mine and combined with a 160 t-stat and having the fan programmed to come on as I type this, it's certainly cooler around the TB area... course living in FL I'm not worried about icing of the blades.
 

WhalePirot

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After the results of my dyno run, I have little faith in them.

My science training says the the results on the link are probably within the margin of error; hence not an a absolute indication of anything but normal variations in equipment.

:w
 
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A counterpoint, Whalepirot. Consider an intercooler on a turbocharger. 1) Air passes through it in seconds, yet it manages to reduce intake charge temps by 20-25 degrees. 2) throw ice on the intercooler to chill it before a race/run and you'll see an even bigger difference.

It's not just the throttle body that's cooler on my car after the bypass - the whole intake plenum is nowhere near as toasty. That tells me that either the cooler intake charge is cooling the plenum, or the coolant through the TB also heats the rest of the intake.

[RICHR]
 

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