Throttlebody Idea; I will try it just need a plenum

[grandprix34]

Got a wild idea of sticking an LT1 TB on the DOHC. I know the TB and plenum is one piece but after watching so many American Hotrod and Monster Garage shows for a very long time I feel I have somewhat adapted that attitude...if it don't fit, MAKE IT FIT!

My idea sounds simple enough but it will lead to another intake design me and a buddy of mine are going to start to work on for shits and giggles.

The TB on the 91-93 plenum will be hacked off, leaving a gapping hole on the plenum. Then a plate will be used to attach the LT1 TB to the plenum. Does anyone kow what other modifications would be needed?

[dykz34]

It sounds simple enough, but why not get the 96 intake w/ the removable TB? It would make life 100x easier.

[SappySE107]

larger intake runners arent good for the automatics though (unless they want all top end).

You will have to deal with the coolant setup and the throttle cable.

[quantum110]

The biggest problem I see is doing it so it doesn't create a bottle neck. The LT1 TB is a bit wider than the LQ1's. Can't really tell in this pick, but it is.



Edit: Oh, and If I were you I'd just cut of the plate the the LT1 TB already mounts to and weld that to the Lq1's intake. Hope you know how to weld aluminum.

[dykz34]

larger intake runners arent good for the automatics though (unless they want all top end).

If he is going to strap that big of a TB on, I don't think he cares about lowend.

[93vinx]

i have an extra plenum i plan on making huge mods to even if it means cutsing it to peices, i'm worried about vaccume brakes lowend was never there anyways, need ot figure out if i want two tb's or one, we have some nice for 32 valvers i could get a double off of. what nice about these is that one tb opens until about 30 % thorrotle then the other begins to open, florred the both open wide

[dykz34]

Why are you worried about vaccum brakes?

[SappySE107]

A larger TB doesnt always means lost low end. Looking at our plenum volume, the low end hit doesnt look like it would be too bad. The resolution though going too large would suck, WOT would be in effect before you are WOT.

If you think it has no low end now, try the 96 intake manifolds and then the larger TB. You will surely know then what no low end is.

I also doubt the vacuum will become an issue, unless you slam on the brakes at WOT for whatever reason.

[blutrotdrache]

Interesting. Is there a reason for specifically choosing to do this with a LT1 throttle body?

The reason I ask is that the LT1 throttle body is a twin bore like the LB9/L98 TPI's. It seems to me that the LS1 single large bore throttle body would be the better idea for use with a stock plenum.

Ofcourse, the LT1's smaller bores could be useful with a custom plenum. I'm thinking of an equal length runner design, simular to an exhaust header, with each bore feeding 3 runners (1 into 3). One could use stock 52mm bore TB's or larger aftermarket TB's. This set-up could likely improve power across a wider rpm range than just adapting an LS1 or LT1 throttle body to the stock plenum.