I have done a few Gen 1 head conversions. A typical 23 deg swap isn't hard at all. When you start going with different deg heads the swap gets alittle more difficult but not too bad. Im currently building a max effort LT1 for my personal car. I plan on seeing how far the LT1 block will go, hopefully I can finally put a LT1 in the 8's. Specs on the engine

410ci
4.040 bore
4" stroke
16 to 1 compression
>.730 lift
> 280 duration @ .050
SB2.2 heads, 415cfm intake, 308 cfm exhaust
converted spyder intake to efi
lemons headers 2" to 2 1/8 step 4" collectors
FAST efi
Dual stage N20

here is a pic of the engine just mocked up in the car recently. Should have some dyno numbers in a couple weeks

www.extremeperf.com/images/engine1.jpg

email me at darren94z28@hotmail.com if you have any questions on the swap. I'll do what I can to help

Darren

 

PNYKILR,

That setup you have right there is alot like Jason Shorts. Cam, Heads everything. He is 490rwhp now so I think you will be close to 500rwhp. He's working on tuning and a few other things hopefully going to get it to 520+rwhp.

Monty,

The tall deck block was a good idea, I knew that setup you had had to be prety close to theirs. What intake did you run with that setup?

I also have to agree with you on the 32V heads, they are awesome but getting them to work is another thing.

JSK333,

Your right on with the block comment, I still don't think 800+ HP is a good idea in a LT1 block. It can be done, but you'd never see it in a circle track car for to long.

Max power anything LS1,LT1,SBC for the street is all going to be in the $15,000 range at least, you can get more from the ealier models but it's still expensive.

Darren94Z,

That SB2 LT1 looks like a killer engine. What class is it for?

Bret

 

That is outstanding craftsmanship! Could you get a Hogan intake to keep the stock hood for a sleeper?

What do those heads run? $4000 complete?

 

A "sleeper" with sb2.2's....

I don't see why Hogan, Wilson or one of the custom intake guys couldn't build an intake for the sb if you got the money.

wrt price,
I paid a little better than $5k for my GPTech sb2.2s. Then you need valves, rockers, intake and all the other goodies. Of course you can always buy a raw head and have it worked but most of the full cnc stuff is anywhere from ~$4,200 (18 degree) on up. The comparable Brodix canted valve heads are 2k bare (per head), so you're looking at a bit of dough to get one of these heads (especially the c/v heads) onto an LT. You can find complete 18 degree heads with valves and rocker setups for about $3k as most guys are switching over to canted valve stuff.
If you have the money I have my sb2.2's for sale.... titanium valves, locks, retainers, PSI springs and pontiac spring-oiler valve covers, GPTech cnc program by weld tech.

-Mindgame

 

I'm using a custom Hogan's sheetmetal intake that fits under the stock hood.

 

Hey mindgame, I hit you up for some info on those heads last week and haven't heard back from you. Are you still just waiting on the "all clear" from the engineer? I've thus far only had hands on experience w/ 23* heads so I'm curious about the whole setup. Do they have the IEIE (or EIEI) setup like LS1s or the IEEI of LT1s? Anyway, hope to hear back from you.
As for "taking an LT1 beyond 800hp isn't a good idea", tell that to George Baxter. I don't think he's even running block filler

 

Rich Krause is doing it too. As I have said before, just because guys are doing it doesn't mean it's the right thing to do.

Everything in that block is moving around with that power and that block. There is more power and durablity in just a stronger block that keeps things in the right places under all that power.

My thoughts on that. Not really looking into getting into a dam flame war about it. It's a different opinion guys, take it as that.

Bret

 

Hey Bret, no flames intended. I totally agree. What I'm curious of is the difference in an SB1 and the LT1. Excuse me for not knowing this, my experience is w/ late model factory, but is the SB1 one of GM's bowtie blocks? I wish they'd come out w/ an LT1-like aftermarket block, ala Motown 415, etc, etc.

 

LT1, I must have missed you somewhere along the way. I don't remember ever getting an e-mail or PM from you.

Or maybe this is something I missed in another thread?? Either/or, send me an e-mail or PM and I'll get back with ya.

On the block thing, I agree. You can push good power from a factory block.... guys have been doing it for years. But you lose quite a bit too when you really start pushing the power (2+ hp per ci) especially with nitrous. I think the block just gives alot up to the stress.
As a matter of fact, an article some years back performed a test where they took an ~800+ hp nitroused 392 ci small block built and assembled by Fulton Racing Engines on the 010 block, did nothing other than swap out the components to a bow-tie block and they picked up some ~20hp and ~25 ft-lbs with the swap. The 010 block was freshly machined and the engine had like 8 runs on it before the comparo. It was also given a clean bill of health.
Coolest thing about it.... the numbers were better all over the place, not just peak. That should tell you something right there.

-Mindgame

 

Its been hoped and dreamed before, problem is these engines were made for barely more than a handfull of years, too small a market.

 

Thanks guy's. I'm sure I'll be happy with my present combo, but would like other options. Maybe next year I'll go 1st gen small block to give me other options on head choise, Then again maybe not. I'll be running a 200shot through my current motor. but would like to get rid of the NOS all together. Who knows, maybe I'll go forced induction next year, if the funds allow.

 

With regards to the SB2.2 heads, 415cfm/308cfm (intake/exhaust), these are basically high output heads used on Nascar engines, right? So using these on the street would be pointless cause they are for high rpm use and getting caught up in traffic would be a bad thing, eh? No low end grunt?

And could someone explain canted valves? And why is this the new thing?

Thanx, Rob

 

Yeah 400+cfm SB2 heads are NASCAR heads. They are usually high in port volume, like 270-290cc, but since the port is so long it's not like a 23deg head, it would be more like a 240cc-250cc port there.

You could make a street car engin out of these heads. You would need a mild cam because they flow so dam well, and a good amount of cubes. Since they flow so much cfm they will still have be high velocity so shouldn't be too bad on the street. The right combo could run them though.

Canted Valves is like a big block head. The valves are not just angled in one direction like 15,18,23 deg but in the the other plane as well towards the side of the bore (looking at it from the top) This allows you to get more valve in the bore and less shrouding from the cylinder wall. SB2, C5R BBC and some small block heads use this.

Bret

 

I agree that making 800+hp with an LT1 block is kind of foolish. None the less, it can be done sucessfully in light of how most people use this kind of hp in a street or street/strip car. Basically, it's not run at WOT for more than ~10-12 sec. at a time. Think about it. 10-12sec of WOT from a dead stop takes you into the 140+mph range. From a roll (like on the street) you would be well in excess of 160mph in that time period.

In addition, if we are talking about a forced induction setup, the motor is not going to run at extremely high revs. In my case, I was shifting at 5,800 last year. Rpm's have a lot to do with mechanical stress on a motor. This years teardown was interesting. The context is that the motor was put together 2 years ago and run for 8,000 miles with maybe ~75 runs at the track, ~1/2 of these with nitrous. The fastest runs at the track were at the end of the season. IOW, it was running fine. It was making 733rwhp with the N2O and ~600rwhp with just the blower. It was in pretty decent shape. Leakdown was <5% on all cylinders. There was some evidence of the heads moving a bit, but the head gaskets were in good shape. The rods and pistons weere fine. There was some evidence of things moving around on the bottom end. The bearings were kind of "flakey" and the main journal were a bit squared off and required taking off 0.010" to get them back to round.

Overall, that's pretty damn good IMHO. Took $900 in parts, machine work, and assembly costs to completely freshen up the shortblock including new cam bearings (which looked fine, BTW). This year I am going to push it a bit harder. Redline is going up to 62-6,400 and hp should be up ~100 due to better heads and a better blower. We did a partial block fill, in an attempt to strengthen it up a bit.

Time will tell if this is "too much" for the LT1 architecture for my type of use. If it is, I would go to a gen I small block. The relvance to this thread is that I would NOT bother with gen I heads on an LT1 block. LTx heads can flow enough air to hit the limits of the basic LT1 architecture. If you take full advantage of gen I heads, you are likely to need a stronger block (eg Bowtie or aftermarket) so why bother putting together a combo like that?

Rich Krause

 

Very good points, Rich.

I am concerned that your new redline (and more hp) will exceed the block's limits to contain the parts. Of course if you don't try you'll never know for sure.

If (when?) it goes, you'll be able to start with a Bowtie or equivalent block, and a "clean screen" design.

Hey, live on the edge!

Jon