Hey guys, what's up?? I am in the process of looking for a LT1 block to start a 355 or a 383 build. I have a few questions for those of you who have done this already. I will list the questions since there are alot..lol.

#1) Does it matter what year block I get, since mine is a 93 w/ speed density or can I just convert any year LT1 block?? I just bought a MSD Opti Spark thats why I'm asking, rather not waste a $540 opti spark if I don't have to.

#2) What would you suggest for a good street engine, probably not going to see the track much. A 355 or 383?? I'm going to spray it too, probably a 125 shot. Also as far as rotating assembly, what should I get? Can I use cast steel crank or should I go with all forged internals??

#3) Have any of you guys got your 383 engines to pass emmisions but still put out decent power?? I know having to pass emmisions limits you on your cam choice but just thought I'd ask.

#4) Should I use my stock intake and heads or LT4 heads, have them ported by Llyod or should I get the new Edelbrock intake and some aftermarket heads and have them ported??

Sorry for all the questions, I just want to do this thing right, if I'm going to do it. I thought since most of you guys have already been through this, that you could probably answer all these questions. If some of these questions have already been asked, I apologize, I searched but nothing came up that answered my questions, unless I overlooked it. Anyways, any help would be greatly appreciated.

-Nick-

 

as long as you dont go too wild with the cam and you keep all the emissions equipment on you might pass emissions. Lloyd Elliot is definatly the man to talk to about your heads and cam, and as far as the bottom end goes, talk to Chad Golen from Golen engine service, (www.golenengineservice.com), he has pretty good deals on fully assembled short blocks, he also has a pretty good selection of fully assembled long blocks, plus very good customer service.

 

1 -- Block doesn't matter, they'll all interchange.

2 -- If you want a powerful street motor, I'd do a 383 for the extra TQ/displacement, forged internals and a smaller cam like a 224/230 or thereabouts to keep a much more broad powerband.

3 -- You can make more power with a 383 and pass emission than with a 355. GMHTP a few years ago used their 93 Formula "Thunderchicken" with an MTI 396, heads, and a CC305 and made something like 415 to the wheels. So yes, it'll pass with the right setup.

4 -- Don't waste the time on the Edlebrock intake. Use your LT1 heads/intake and have them ported at any number of reputable shops.

 

Thanks guys, I really appreciate the help. I scored a bare LT1 block for $150, so let the madness begin..lol.

I have another quick question...If I wanted to use a LT4 intake w/ LT4 heads, what do I need to do in order for them to work w/ my 93 stuff?? 94+ fuel lines and fuel rails??

 

Yes. The 93 stuff will bolt up but won't look right. The rails you should be able to find used for ~$40 and the lines new are $15-17 from GM.

 

What do you mean "won't look right", can you explain please??

 

94 and up rails had a crossover up by the throttle body, and there is a groove in the 94 and up intake manifolds for the crossover, and im pretty sure that there was never an lt4 intake manifold that was made with the groove.

 

Close. I think what you meant to say was that "I'm pressure sure that there was never an LT4 intake manifold that was made WITHOUT the groove." ALL LT4 manifolds had the front fuel rail crossover recess in them.

The 93 fuel rails had the crossover at the back of the rails which sat behind the manifold.