I've searched a little but didn't find anything. Mainly on single plane LT1's with monobody TB's with elbows.

How difficult is it to modify the LT1 intake to accept a monobody TB? I have access to 70 and 90 mm TB's and want to know if it will work decently. I've never seen the inside of the LT1 intake yet, so I don't know what it looks like. Seems to be as easy as cutting the opening to be round.

I realize there is a problem with tip-in lean with 90's so I don't want to go that big to start with.

 

You can buy an aftermarket bolt on monoblade TB for the stock LT1 intake

 

When you bolt that up, it requires cutting the stock manifold? Does the monoblade not have the lean problems with tip-in?

 

Unless you are making 550+ horsepower normally aspirated a monoblade is a waste, it flows 1300 cfm. The round 70 and 90 mm TB's like on a Ford will not work on the front of an LT1 intake. The hole for a monoblade is oval.


May be a way to mill the top down, cap the front and mount it on top...that would be interesting.



David

 

I can't remember exactly, but I think a dual-ventura 58mm LT throttle-body flows 1050 CFM (carburetor equivalent). I'm running the 58mm Holley throttle-body with my 396 stroker and really like the Holley.

WD

 

TPIS 75MM Billet LT1 Throttle Body:



http://web.camaross.com/forums/showp...90&postcount=5

 

This part was designed for the streetrod crowd I.E. look good 1st, perform second. It has no performance advantage over a cheaper twin bore TB.

BTW I dont see in my head where that would work on the front of a LT1 manifold, just LOOKS like it would not fit...GM Ramjet maybe?




David

 

Im sure there will need to be modifications but I see a huge improvement over a twin setup. This is definately geared towards the street rod with an LT1 transplant. The MAF bolts directly to the front of the TB... with a little modification this allows you to open up the actual air intake and maybe make it a little larger and less funny shaped. People that want to make those homemade CAI and elbows can now shope at Home Depot instead of the local speed shop. haha

 

How do you see a "HUGE" improvement over a twin setup? In the link you posted above, they flow the same as a comparable 52mm TB...where is the advantage?


David

 

Between those two trains of thought, I'm sure there's a happy medium in there somewhere. Just not sure where....

 

You took my first quote out of context.....thanks.



David

 

I actually happen to agree with your first quote. There are very few LT1's that can move enough air to justify a TB of that size. What I mainly see as an advantage with the 75MM TB is that it opens up the possibility of more induction options for the LT1 crowd. (Namely, the recent trend toward adapting LSx based induction components.)

 

I don't get it. Then why do the imports have such HUGE TB's if there was nothing to gain? The 90mm is a STOCK Q45 4.0L TB. Hell, the Honda D16's and B series use up to 70mm. What gives? I know they rev the crap out of them, but the LT1 is a 5.7L. It should flow more air at 3000rpm than a 2.6L at 6000rpm. And they all have 2.0L and under!

Just seems like all I hear is that everything on the LT1 is designed good enough to not have a problem anywhere and that there is nothing to gain by modifying the little stuff. Do mods always start with heads and a cam? Will only then do the little things matter?

 

My guess. Throttle response. Have you ever driven an import vs our lt1 f-bodies. I am currently driving a Mitsubishi Montero sport with a 3.0 liter v6.
By no measure is it faster or more powerful than my lt1. But the throttle response makes it feel so much faster and makes it fun to drive. Granted its not nearly as fun as my firebird but it does feel fast. Most of it on the montero is gearing. But I suspect throttle response has a lot to do with the decision to use a large throttle body. So why didn't gm use a large throttle body for the LT1 to pick up throttle response? Space reasons mostly would be my guess. But the montero also gets stuck at the drop of the hat (no 4wd or even limited slip but it does have 275 tires IIRC). Lower throttle response can help keep you from getting stuck.