I have been reading up on people who have had a set of sbc 23* heads converted to an lt1 by machining them for coolant bypass...welding up the old bolt holes and having new ones drilled that match the lt1 block. It seems fairly common and fairly inexpensive at about $400 or so...

My question is, what headers are you guys running? Will a standard lt1 jet hot long tube fit? If I do it I would rather not go custom headers, what will work? Thanks in advance

 

All sbc/lt1 23 degree heads can use the same headers as long as the exhaust ports aren't spreadport. (intake and coolant passages are the only real differences.) So your current headers will work fine.

 

Would these kooks headers fit also?

http://www.kookscustomheaders.com/sh...=&make=&model=

Think I would need a 1 7/8" header over my 1 3/4" if I was buying a nitrous motor with sbc 23* converted heads?

 

Yes, those kooks would work fine. 1 3/4" would be fine with your setup on the nitrous. If you are going to step up get a set of full 1 7/8" headers with the stahl adapter flange. Hedman makes an awesome header for $680 from summit racing.

 

who converts em and what is a good head to go with. i've heard of people doing it but wanted to find out more about it

 

Do a search here and in the LT1 Tech section and you'll find a bunch of threads on it from a few years back when stock LT1 castings or AFR were the only options. With Dart, Trick Flow, and other LT1 options now on the market you'll find less reason to do it.

The exception of course is for 18*, 15*, 11*, etc... SBC heads which don't have LT1 set ups available... those are still "converted" by a good welder/machine shop. Most engine builders / shops can tell you who their local welder is for cracked heads... pretty much the same thing, but with some machine work after to clean up the surfaces and tap/thread the bolt holes. Still, it's best to find a shop that's done similar work already and is familiar with the LT1 angles/pattern needed.

If you're going to pay to convert a head, I'd look at 18* or 15* heads instead. Most 23* heads can be matched with a ported/valved Dart or AFR head... even stock castings can go pretty big with the right porting and new valve seats. It's worth noting that any new valve angle will likely require new headers and pistons. The 18X heads that use 23* hardware are the exception, but unless you get a spread-port version (and headers to match), you'll likely be at the same cfm limit the stock castings have at full porting. For 23* heads, the stock castings are very usable/portable.

What's the project goals? (hp? cfm?)