Has anyone on this board swapped a gen 2 LT1 into their cars and used a carb instead of the fuel injection? I am looking to do this swap in the near future so i would like to hear similar experiences from this type of install.

fuel injection is out of the question so don't try to convince me otherwise; it WILL NOT work for my application/plans.

thanks
Denis

 

wtf

 

I am in the process of gathering parts to put a 97 LT1 in a 70 Z28, with a T56 behind it. I will be using the GM intake (325 or so from Jegs), MSD distributor, and a 750 Holley. The motor is currently in my 68 with DFI, but I am building a new motor for that car to free up the heart transplant . I saw a post somewhere about an opti plug, so I need to research that some more, and getting accessory drive on the front of the motor is still up in the air, since the stock F-body a/c mount won't clear the subframe without major surgery. I have heard the Corvette bracket will clear, and also, there are companies that make the brackets for street rods, so something will work..
So far as setting the timing, I will probably do the old fashioned "set by ear" method.. drop it in at TDC, get it runing, then twist it back and forth until it sounds good! May have to mark the stock pulley, but since the hub is not keyed, there is no gaurantee that it won't move.
So far as engine mounts and exhaust, the 2nd gen parts bolt right up..

 

Went and did a little research; the plug for the Opticrap is GM p/n 12367600, $48, avail from GM Performance parts...
Found some pics of the Corvette bracket, will work for our cars; and I have an email into Street and Performance about their brackets.. I'll post it up when I get a reply
FYI, as I progress on my project, I add pics and notes to my homepage, so feel free to check back from time to time, especially since it finally cooled down enough to work in the garage!
Major parts of the project will be:

- front engine bracket
- cooling system/radiator needs for the reverse cooling
- trans crossmember
- adapter plate for the clutch slave cylinder
- modifying a late model TA console to fit
- adapting 4th gen rear disc brakes
- building a gauge panel with Autometer Phantom gauges

and whatever else my evil mind comes up with!

 

If I'm not mistaken, GM never made a carbuerator intake for the late model LT-1. They did have an LT-4 crate motor with a carb intake on it, but the intake ports are raised 0.100" over the LT-1 ports. So I guess you could use this intake, but you'd have to port it and the LT-1 heads to match each other if you want the ports to align properly (unless you just got LT-4 style heads).

Good luck!
-Dave C. '97 Z28

 

GM performance parts makes and LT4 and an LT1 style carbuerated intake for this type of swap as well as the plug for the opticrap that the LT4 crate motors used.

As far as the braketry goes, I won't be using the A/C compressor so my framerail will clear the brackets.

 

The intake for the LT1 carb from Scroggins Dickey is $205... they beat Jegs all to hell!!
Amazing...

 

their site is www.sdpc2000.com

and yes, they have some great deals. I'm sure they do some high volume since they specialize in engine components mainly. Their Vortec packages are nice too. Everything you need to put vortec heads on your car and they come with z28 springs so you can have a .550" max lift

 

If you get the a GMPP cata;pg they have the LT1 intake and LT4 intake since there is different runner angles.

They do make a opti plug and they also have a timing tab on it if i recall.

Just grab a book there is a bunch of stuff that most do not know about.

I have seen three carb'd LT's so far and all have gone faster with a carb on them versus the FI.

I thought about it at first but will just be going with a gen one block in my 4th gen instead to be different

 

If you're ditching the FI system and the Opti then what you're left with is basically a 350 with revers-flow cooling and aluminum heads that are basically on-par with a set of iron Vortec heads as far as runners and combustion chambers go, as far as I can see. Interesting but worth the headache dealing with the bracketry, unique cooling system and such? I don't know.....

Would an old Gen1 350 with good aftermarket heads and intake be a cheaper way to go? Well, if you already own the Gen2 LT-1 then probably not. But if you're buying everything new it would be worth thinking about long and hard.

 

The reason I am considering the LT1 is because there is a guy that has 50 of them and is selling them cheap to get rid of them. Most people around here seem to think that the're stock X00,000 mile 350 that burns oil is worth $500 in any condition. I already have one of those in my car at the moment. It would wind up costing me way too much money find a decent shortblock that would still be used, get the vortec heads for $400, another intake for $300 and I'm still like everyone else with a vortec headed 350 that makes about 250 hp with 9:1 compression. I like the idea of a cam driven water pump and 275 FI hp. What would that # be with a carb seeing that the stock ECM kills the performance of those motors? I really don't have the time to F around with assembling an engine and tracking down parts, I want to just have to call GM, get the required odds and ends and drop it in.

 

You really are not going to gain any HP over a stock LT1 by throwing a new intake and carb on it. the intake design on a LT1 is superb and the FI on a stock engine is a perfect mix of MPG and HP. You will gain nothing but probably loose.

Now if you put together a different setup on a LT1 interms of heads and cam there will likely be gains with a carb versus FI since you can tune it at your house and change thing easily for little to no cost.

If you have a FI heads and cam car you can tune it as well or have someone else tune it but it only goes as far as their knowledge and it will cost you. Or you can learn to tune it yourself and pay the money for the tuning hardware.

What really matters is your plans and goals.

 

:quote: fuel injection is out of the question so don't try to convince me otherwise; it WILL NOT work for my application/plans.



I am not looking for a big brother to overlook my tweaking of the engine and I will be using the TH350 that originally came in the Z

I also have a dire hatred for computerized engines as I have enough stress already with carbed engines and I am looking to make this as cheap as humanly possible so PLEASE keep it to carb specific replies.

thanks
denis

 

I also have a 95 vette cam to put toward this project too.

 

Well im gonna go out on a limb here and figure that you really dont know a lot about makeing power..Why waste your time with that intake and its tiny little plenum...You could easily get any comitent machine shop to drill and tap the standard inatke face for you..They should only take an hour to do this..Then you could step up into a perf RPM or better yet a victor for a race setup..

Ive thought about swapping to carb setup on my mazda but after tallying up all the parts needed to run methanol and be able to switch back to gas i said no...