I am thinking about putting a 350 crate motor in my car. It is rated at 350 horsepower. RB83L69 sugested using the TBI with truck injectors instead of my original idea of a carb. I was considering replaceing the cam in the 350 with a LT1 or LT4 cam. Would this be a stupid thign to do if I use the throttle body? or is it even doable? I am thinking about using this type of cam because my uncle has a '96 LT-4 Corvette and I love the way it idles/sounds. I don't want to sound ignorant, but I am at least a little .

 

You can use those cams with a 350.If Iam not mistaking the dowel pin may need to be shorting.You also need some chip burning,but may get it in the ballpark to run decent with adjusting the fuel pressure.But if you use a carb it won't be that hard to tune. But chip burning is a must if you keep it TBI.

 

Check out this thread devoted to LT1 cam installs in TBI equipt vehicles.

LT1 cam digest

Make sure that your new 350 is a roller motor as the LTX cams are hydraulic roller set-ups. Your motor will also need chip work to make the most out of your new combo. Without it your motor won't be nearly efficient as it should.

 

Chip burnung. Great. Getting the motor running with the new chip and cam first before I install it a good idea? What if it were a hydrolic lifter? I can change the lifters, right?

 

It is a good idea to get familiar with chip work before you even do your first serious mod. That way you know what a good tune looks like and what changes affect what. You can improve on the stock tune and plenty of practice will make your life easier when you have a motor that will soley relly on your ability to tune it.

You need to see if your motor is a roller motor. If it is not you can either retrofit it to accept roller cams or you can buy a flat tappet cam which it is set up for.

 

If its not a roller, then the flat tappet is the cheapest way to go. I was pricing up a roller conversion and it was like 300+ just for the linkbar style lifters.

As with any efi setup, youll need to learn to tune/burn chips. Anything thats controlled by a computer is going to at least need to be calibrated. The hardest part of tuning is usually the fact that you need to know a bit of engine theory to make sense of it all. TBI is as good as anything to start with. If you dont like it you can always move over to an MPFI setup with a 7730 or go aftermarket.

Even yestercentury technology like a carb is going to at least need some tuning to get everything as close as possible.

 

BTW, what are the specs of this "350 HP" crate?

 

Sorry about the delay. My dad found it in a brochure at a car show in Knoxville. It a rebuilt 350 that is rated at 350 horsepower. World or Dart heads, new. 2000 dollars for the motor, before shipping. I also found these on ebay 357 HP and this 370 on ebay. What do you guys think? There are a few more: 328, 417 and 470 HP. But these are too much money or too little horsepower for me.

 

Those crate motors are sold with the intention that the owner uses a carb and then tunes it properly in order to make the power/torque numbers (or get close to the advertised power/torque numbers, assuming the seller isn't FOS). That assumption also holds when installing the crate motor into an EFI car like your 3rdgen. So for you that means serious changes to the EPROM (chip) in the ECM (because it's set up for an LO3 right now), a substantially better fuel pump, larger injectors and increased fuel pressure, and probably some kind of larger throttle body (depending on which engine you choose), and certainly something low-restriction on the exhaust. And more tuning. So it's a LOT of work for an experienced person; it's even more work for you and you will probably be very unhappy with the results because it's not likely you will succeed unless you devote time to reading and DIY programming. Many people have been down that path and been unhappy with the results because they really didn't know what they needed to do to get the combination to run properly. And you really want to avoid that, if possible.

You would be much better off aiming lower and shooting for 230 fwhp and 330 fw ftlbs by buying a crate 350 and starting with the LO5 (9C1) copcar baseline, doing a port cleanup, and then modding the exhaust and air cleaner. The tuning demands will be MUCH less and you'll run in the low 14s. HTH.

 

I knew about all the work involved. You just made it sound really scary. I thought about modding the current motor, but that wouldn't be as practical as just buying a Z-28 or something. Not to me anyway. That may be what I end up doing, modding the current one. The only thing that I think I will have trouble with if I go with a crate motor is the EPROM. I thought about using a carb and doing away with the TBI, but a guy told me that using an aftermarket throttle body, etc would be cheaper and easier.

 

Ok, I had another thought. Well, actually it was a thought that Kdrolt started. Can I use the stock computer on a set of iron Vortec (or similar) heads with a bigger throttle bodies and injector? I know they make TBI/Vortec intake manifolds and that I will need one, but I don't know about modding the EPROM. Thanks.

 

ya do know that the tbi/vortec intake is over $300 dont ya?

thats some serious $.....(well at least for my tight ***)

 

Use the carb manifold with an adaptor. Itll be cheaper. Requires some tweaking of the throttle bracket and some other relatively minor stuff, but nothing really crazy. There is also a wider selection of manifolds if you think you need more. If your REALLY cheap, you can use on of the ebay knockoff vortec carb manifolds. The casting quality blows, but theyre cheap.

 

here's the intake they recommend....http://www.sdpc2000.com/cart.asp?act...d=738&pid=8154

i talked to a tec guy at scoggin dickey, he said not to use the carbed intake with an adapter....he said it wont work nearly as well

 

that's because he was talking out of his a$$. A carb intake with adaptor would most likely make more power if you chose the right one.

 

91_ _ TPI, where bouts you live in them there hills? I'm in Clinton. You could buy a LO5 short block then add the cam and heads of your choice for a good starting point. With some good prom tuning you should have an engine you could be happy with. Just don't go too radical or tuning could be a big headache.

Steve

 

I live in Elizabethton, near Bristol. I thought about the L05 short block. Where could I find one at a good price?

 

www.sdpc2000.com

 

Surely someone in Bristol will be able to sell you a good 350 short block. You should also check around at a couple of Chevy dealerships for their prices too.

Steve