I'm playing around with an idea that I want to put into play next winter.


Without getting into the details of that idea, I was wondering one critical thing, which has to do with planning the bottom end.

On a 383 with an X-Trim blower and a set of AFR227 heads (or something of similar flow), pullied for approximately 15-16lbs at 7000rpm, what sort of HP would the combination be putting out?

I don't need exact numbers, I just need a reasonable guess, so as to make a better selection of crank/rods/pistons.


Please don't critique the parts choices. That's a different subject, and not what I am looking for.


I need to know, for THAT combo, a best guess on the HP range.


I have to draw up a budget for this buildup, and if I want to keep on schedule, I need to begin the planning NOW, so obviously; I need to know what I am going to have to buy.

 

We're thinking that an X trim will make around 950 rwhp on our motor (414 LS1) and a XX trim would make around 1100.

 

Is this going to be through a manual or auto transmission? I would think with a 6-speed you can make close to 900rwhp. With a TH400 I think you will be in the 850 rwhp range.

.... Remember you blower will max out at 58K so in order to rev the car up tp 7000 rpm you will need to run a big crank and blower pulley.


Good luck with your setup.

 

OK, so it's as I suspected...

Dragonslayer and Oliver's.

 

What the ?

 

X-trim with the appropriate parts can make about 1100rwhp... there is a drag radial car that runs with us that has gone 170mph on drag radials @ 3315lbs through a powerglide..

 

We're working on a similar project, but the details are extensive and as such are better discussed on the phone.

In terms of what you should expect to buy for an X trim car, can you give us an idea as to the current build of the car you have in mind, e.g., is it stock, heavily modified, etc. In general, you not expect to retain many stock parts in such a car.

 

Dragonslayer crank and oliver rods.

The HP estimates you guys are posting mean that I have to build a more serious bottom end than I thought.

 

Without doubt such a build would require a completely custom engine with the finest parts available, preferably built by someone or some shop that has demonstrated that he/it has built 1100 hp motors that will stay together for 30 runs or so, which is about how often we would freshen it. Such a car would require changes from bumper to bumper, almost every key part would have to be replaced.

 

I'm not worried about the rest of the car. I will do what needs to be done.


What I'm concerned with NOW is how well an LT1 block will hold up to this power.


I know there are people running that kind of power on a factory block, and I have a well seasoned block to start with that I can probably hold to a .010 overbore. (Which I guess means that I'll be building more of a 380)
I can convert it to 4 bolt mains, I can line bore it and square it up, and even fill with hard-blok to the bottom of the freeze plugs.

However, as much as I am attached to the idea of using an LTx engine for this, I have to seriously question the wisdom of it when I am looking at this much power.

I might be better served by just selling off my complete, running engine with all the accessories, and beginning with an aftermarket block. I can still reverse cool it, I'll just need to do it differently.

 

Everyone will have a different view of this issue, but, if you're not attached to your LT1 block/engine at the hip, you might want to step back and reevaluate your project. If you're really serious about building a +/- 1000 rwhp car, we would suggest changing to a resleeved aluminum LS1 block, C5R or Dart block.

We're using a 6L CI block, machined more than the space shuttle, and we would not use this block if we could start over again nor if we build a new motor. Unless we break something, we'll have new dyno results within a week; we expect to make over 900 rwhp.

 

we have a stock blocked LT1 motor that goes 160mph+ at 3420lbs.... its a 383 with good internals.. If all goes right, it should go considerably quicker this weekend... this combo as of now is probably 1000rwhp thru a t400..

 

I was thinking Motown if I go that route.

I like one of the new products they have out.

 

Another alternative is to forget the LT1/LS1 stuff and buy a 850-900 hp SBC for $14,000, put a small shot on it and have one inexpensive and mean street machine.

 

Well, after a ton of experience, Baxter abandoned the LT1 in favor of the SBC. I'd think that speaks a lot. I'm not convinced the LS block is as strong overall as the LT. The main advantages I can see is more cubes and better heads. The main excuse I can see for building an LS engine is the idea of pushing a current production engine to the limits. That can translate into new products etc., and can help feed the aftermarket industry and tuners.

The idea of building a "...budget..." 900 hp small block is a little far fetched. If you just wanted to build a stout motor that would hold up to the power, then a big block is the way to go... It's all relative to what you want and desire.

From reading your responses, it sounds like you're leaning toward the Motown/exotic small block solution. There's certainly a lot of cool stuff out there for that, but it won't be budget...