ccracin

I had posted in the 305 to 350 swap thread, but it would be more correct to start a thread. I just picked up an 88 TBI 305 car with a siezed engine. I want to make daily driver, but I want to add a 350. Used high mileage engines are all I can locate and they are not cheap. So I was looking at the following engine from GM. I can get it at a pretty decent price.
ENGLM1LS9

Part #
10067353

Engine Name: 350 LM1
Horsepower: 249 HP @ 5,000 RPM
Torque: 304 Ft/Lbs @ 3,500 RPM
Compression Ratio: 8.50 to 1
Block: 4 – Bolt, 2 Piece Rear Seal, 4.000” Bore
Crankshaft: Cast Nodular 3.480” Stroke
Heads: Cast Iron, 76cc
Valves: 1.940” / 1.500”
Camshaft lift: 0.390” / 0.410” Hydraulic
Duration @ 0.050”: 195° / 202°

The cam is not radical and it has decent power numbers at a reasonable 5000rpm. I am going to try to get a 746 ECM this week coming. I was hoping to just change my injectors, fuel pump, ESC module, and knock sensor. I was going to use the 305 intake and throttle body. I was hoping there might be an existing .bin that would run this engine. I am willing to buy the burner and chips. my goal was to get a .bin that would be drivable so that I could run the car and then learn the tuning part over time. Does this sound reasonable with this engine? GM also has part#12568758 which they list as an 86-95 L05 that is a few hundred dollars more than the one above. I just can't find details on it. Anyway that's where I'm at. Any comments or specific help would be great.

Thanks,

Chad

90c350

I think that if you are going to swap in a crate motor that is fairly mild, I would choose the 290hp version. It has better starting potential and a better power curve. I cannot think of the prt# or engine name right now but it is on the Gm website. Just my thoughts. I quick cam and head change and your making an easy 350/370hp with a stock bottom end!! You will need to beable to tune it a little more of course but that should be something to consider anyhow. Hope that this helps.
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Sorry the engine part# is 12499529. I think that would be the way to go without any major cash out.

Fast355

iTrader: (2)

I would pickup a stock L31 350 Vortec longblock. They run very strong, are super torquey, and get great mileage. It is tough to appreciate one until you have driven one of the heavy trucks they came in. For example my stockish G2500 Express would do 0-60 in 10 seconds, 0-70 in 12.5 seconds, and 0-80 in 15 seconds. This was with the doggish 4L80E/3.42 gearing pulling over 6,000 lbs.

Here is how it runs with no internal engine mods, aside from 1.6:1 roller rockers.

http://www.youtube.com/watch?v=WydwLghk_yw

ccracin

90c350:
i have looked at that engine, I just wasn't sure how much custom tuning would have to be done. I really need to be able to drive it very quickly. As I learn tuning I can upgrade parts. I'm an ex-stockcar racer so I can tune carbed engines pretty well. The EFI is all new to me. Any thoughts on the amount of tuning that would be needed for this engine?

355:
I was reading some of your other posts about your van. Pretty awesome for a party wagon!!! I wasn't looking at the vortec stuff because of the intake manifold bolt pattern issues. I wanted to use as much over as I could to start with. No matter which route I would go with a vortec the intake change would run another couple hundred. But, Ii will check and see what I can find and price them. How much tuning would be needed with this long block? Could I use a stock 350 chip of some sort?

Thanks for all the info, I really want to get moving on this project. Comments from anyone are greatly appreciated.

Chad

90c350

Hey Im pretty sure that you could get buy for a short time with the stock tune and some timing adjustments along with maybe some more fuel pressure. I have also just got into chip burning and My 350 swap went very easy with the gm 350 stock tune. I could only use part throttle for a while but it got me back and forth to work with no problems and would cruise down the freeway alright!! Of course it only is getting better with the tune. I have a little larger cam than the 290hp crate and a better intake etc. The chip burning equipment is cheap considering the price of aftermarket chips. I think you could get your basic's down in a day or so and beable to drive it without any major problems. Hope that this helps

blimko

iTrader: (1)

racin: i see your an ex racer and know how to tune a carb ok. so why not switch to carb? that way you can get away from the whole efi idea, and not take as much time to tune. also you wouldnt have intake issues as the carb intakes are much more common that tbi aftermarket ones and cheaper too. if you already know how to do something...stick with it huh?

ccracin

Blimko,

Believe me, I thought about going that route. I have several reasons for staying with the TBI. One is we have emissions checks where I live in PA, so between visual and sniffer checks I want to be OK. The next is fuel economy. I think I can get better fuel economy while not sacrificing too much power from TBI. It isn't so easy to have both with a carb. The third is, I am in the process of building a 68 chevy pick-up for my Dad. It is going to be a street machine. The power comes from a 502BBC. It is going to have either FAST EFI or BS3 EFI on it. I thought this would be a great way of learning the basics of efi tuning. Besides I have the complete TBI setup, I just have to taylor it to the 350. I would have to buy all the carb stuff. I got rid of all that stuff with the race car. It was custom built for circle track stuff. Thanks for the response.

Chad

BMmonteSS

CCracin,

If you want to save a buck or two you might see what you can get a jasper crate engine for. They will be rebuilt, not new like the GM crate motor but it could save you enough money to put the vortec's on now along with the vortec specific intake.