I see all the posts talking about converting SBC heads to reverse flow cooling so they can run on a LT1 block, I understand that. What I dont understand (and I hope someone will school me) is why a SBC long-block setup can't be used with the LT1 fuel injection system. I'm sure you would have to make a custom sheet metal intake manifold like a Hogan's or maybe Bret could fab one up for right amount of $$$. But what else holds back the full conversion.

Nothing against all the guy's running carbs but a carb setup will not pass emision plugins in my state. Before I shovel mountains of $$$ at my current setup in the attempt to achive 450-475rwhp, I would love to know if I could just build or buy say a motown 434 c.i. motor and make it run with obd2.

Ignorance is bliss, somebody burst my bubble.

 

Lots of sensors you need to find homes for. Map, MAF, IAT, knock, Temp sensors, 02s etc etc. No reason it wouldnt work, just lots of custom work to get it done.

 

Most of those sensors are part of the intake manifold set-up or exhaust, both of which would have to be custom made anyways if you go the route of converting SBC heads to reverse flow cooling.

Are there any major mechanical issues that need to be addressed concerning the ignition system. I know the hole for the distributor shaft would need to be addressed, maybe just a dummy shaft chopped off flat with the intake so the oil pump would work (custom I'm sure). Also, could a magnetic crank trigger be used to run the ignition?

Somebody tell me I'm wrong and slap these stupid thoughts out of my head.

 

It might be cheaper, and certainly easier, to just get a TPI fuel injection system from an L-98 engine with the high flow runners. That system is already designed for a regular SBC, and can support plenty of horsepower.

If you're going to put it in a late model F-body you may have clearance issues, but they sell manifolds similar to the LT-1 (like the mini-ram, etc). Of course, there is some money involved.

-Dave C. '97 Z28

 

The LT1 PCM will only work with the high and low resolution cam position signals from the OptiSpark distributor. It needs those pulse signals to set the ignition timing and the sequence on the fuel injectors. The OptiSpark will not work with the Gen 1 SBC.

I don't see how you could use the LT1 setup on a Gen 1, unless you could simulate the pulse signals (Electromotive used to make a chip that allowed this to be done from a crank timing wheel - but it can't synch the sequential injectors correctly to the cam position). Or possibly adapt an OptiSpark optical sensor module to the inside of a stock Gen 1 distributor.

You would be better off just putting whatever injectors and ignition system you wanted on it, and run a FAST or an Accel/DFI.

 

Arent Standard SBC timing covers the same as LT1s as far as bolt holes are concerned? If so just run a LT1 cover and just have the cam made with a dowel drive pin.

You can then grab a crab cap distributor and run it out back. Just have the ecm fire the coil to it, instead of firing to the opti.

 

sorry to say but it might be better just to grab a 730ecm and a speed density setup. that would make a pretty easy swap.

 

The ignition thing has been mentioned, and your thoughts on the dummy shaft were already adressed many years ago by GM, that is already how a stock LT1 drives the oilpump. As you also said the sensors would be fairly easy.

 

Why not just buy a LT1 w/ the ecm. You can get them for under a grand which will be cheaper than custom fabbing.

 

What about the stage 2 Delteq setup?

That seems to eliminate the optical sensor and still allows the lt1 pcm to work. Could that be used to run a sbc motor?

If you were to add up all the costs to build a 383-396 c.i. LT1 and then have a set of Brodix 18x heads converted, it would be at least 16k-18k. You could build a 427-434 c.i. SBC with 18x heads for much less and you wouldn't have to spin the hell out of it to make comparable power to the LT1.

How much would it cost to make a SBC work?
Less than 3k?

If yes to the above, than you would be into the SBC for the same if not less cash than the LT1. The huge bonus would be a rock solid block and BIG cubes.

But the LT1 pcm needs to stay to pass obd2 plugins.

I have the money, and I want to spend it..........Please point me in the right direction.

 

Nope, completely different. The LT-1 is taller to accomodate the water pump drive gear.

-Shannon

 

i agree dude, just get a TPI setup or a Ramjet setup, would make more then enough power and at least half the work

 

You can use the LT1 intake with the old Gen 1 SBC.

http://www.lt1intake.com/services.htm

You will have to run an older computer from a TPI car in batch mode, but it will work.

 

In my state I have to pass a obd2 plugin and roller emissions for my year car. If the emission computer can not plug into my car and read all the obd2 codes I fail before I even get to the rollers.

If I could get some other form of fuel injection to work with the emissions computer, I would do it in a second. If anyone has the answers please chime in.

If I was to go this route, I would have a custom sheet metal intake made up to accommodate all sensors and fit under the hood.

I would love to do TPI if it would pass ob2 plugins. Or any other after market system for that matter.

 

You may be able to adapt a crank trigger to work, but it wouldn't be easy or cheap. Why not just build an LT1?