Hey guys just thinking about transplanting a non reverse cooled (aka normal) 350 4 bolt main into my lt1 powered car. Here's the catch, I want to run the ls1 computer. I'm looking to build it before I pull the lt1. The reason a older 350 block because they are cheap to build computer and components being the hardest thing to do. I'm not worried about programming the computer. I'm thinking it wouldn't be to hard but I do have a few questions I need to run buy you guys. Sensors maf, egr, O2, coils, injectors, crank and cam position sensors, I'm thinking mounting these would be the hardest part. Anybody know what I'm missing or have any ideas pertaining to this. I'm not worried about mounting of water pump or alt or power steering. Just really sensors at this point and maybe the intake to keep the throttle body in the same area. Thanks guys.

 

I have seen people replace there LT1 engine with a older 350 engine to do away with the electronics
and fuel injection. " old school swap "
not sure if you can use the OBDII system on an older engine

 

You'll have to ditch the stock computer completely when going to a traditional SBC, unless you do some extensive and very custom modification work. Then, there is the problem with the distributor under the cowl...

 

EFIConnection offers the 24X conversion for Gen 1 SBC's.

MAF is simple, fits in the intake duct, not the engine. Why install EGR? The computer operated 3rd Gen engine already have stuff like the MAP, IAT, CLT, etc. sensors, injectors. With the 24X you use the LS1 coil-per-cylinder, with the LSx coils. They supply the cam/crank position sensors in the kit.

Alternatively, a buddy of mine installed a 1,350HP Gen 1 SBC, built on a Dart Iron Eagle block, 383ci, huge Vortech S/C all operated by a MoTeC M8000 ECU in his 97 30th SS convertible..... ran low 8's at close to 170 MPH. Just have a nice line of credit.

 

Yes!!! EFI Connections was who I was trying to think of for the computer. And most the other sensors would be easy enough to mount I suppose. I'm thinking that's the way I'm going. Injuneer answered my question on if anyone had ever seen it done before. Sounds pretty straight forward. I'm not to worried about the money, most crazy ideas do cost quite a bit, like the 1970 crew cab truck I'm building with a fuel injected 396. And I'm blessed to have a wife that lets me spend gobs of money on cars cause she likes the finished product just as much as I do. Thanks guys!!!!

 

Why complicate it with a Gen 1 SBC. Use the 24x on your LT1 and no more Opti. Several people here have done it. Unless you are looking for more than 1,200 HP the stock LT1 block is very close to the GM Bowtie performance block.

I think you have decided the LT1 is not worth modifying because of the problems you've run into.

 

I'm definitely not against building an lt1 block the only reason i was thinking an older block is because I've only found a couple lt1 blocks and when I've inquired about buying them these people think they are sitting on a gold mine. The last guy I talked to wanted $650 for a block that needed a complete rebuild. I just can't see spending that when i can go to the junk yard and get an older block for $150. I will build my original lt1 when i have another engine to transplant but that's a ways down the road and I'd like to keep the numbers matching engine just in case. If you guys hear of someone selling an lt1 near Florida panhandle/lower Alabama let me know. Just a quick question if i do go with an older block will the ls1 intake manifold bolt up or does someone make an intake to bolt up to older blocks.

 

There is a guy that sells lt1 blocks on ebay...75/ea


Larry (Popo8) Co-owner
LTXtech.com

 

I don't think there is a conversion to bolt a ls1 intake on a older engine I was told people have tried
to mill the intake , heads and block with no luck??

 

You can't start swapping LS1 intakes and/or heads onto the earlier blocks.... it's a totally different engine (yes, same bore spacing) with a totally different intake/exhaust layout, totally different bolt pattern, etc.

 

What about the lt1 intake? Is that different also?

 

Different than what? Are you asking if an LT1 EFI intake manifold or an LT1 carb intake (GM Performance Parts) will bolt to Gen 1 SBC heads?

Since there are so many intakes available for the Gen 1 SBC and parts availability is one of your reasons for opting for the Gen 1 block instead of the LT1, why would you then start transferring LT1 parts to the Gen 1 engine? Several people have gone the other way and adapted Gen 1 aftermarket single plane intakes to the LT1 engine.

Bolt pattern on the LT1 intakes is different than the bolt pattern on the Gen 1 heads. Two holes need to be relocated and the surfaces that the intake manifold bolt heads contact have to have the angle changed. Then there's the issue of the water passages (Gen 1 intakes are wet, LT1 is dry) and the thermostat housing (Gen 1 housing is on the intake manifold).