X block, 4" stroke 360-1 Indy head build questions

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zhandfull

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I have a standard bore 340 4 bolt main X block in the garage with 4" stroker crank and some low compression pistons for boosted applications. Don't remember what the compression ratio was but I'm thinking it calculated up to about 7.5 or 8 to 1.
Also have some early Indy 360-1 heads fully CNC ported by Indy when bought
TTI 1-7/8 W2 headers

I'm thinking of doing something with these parts that have been sitting for a couple years.

Wondering how much bore the X block will take? Thinking about that 4.25 stroke small block crank and wondering what kind of cubic inches I could get.

Of course my ideal car would be like Silvia's Valiant with a 500ci small block running 10.00 on a bad air day. Don't have that kind of budget or talent to build a car of that quality.

With that said I would be interested in hearing from the more seasoned builders what kinds of budget conscious builds you could dream up. I would be looking to run close to that 10.00 goal in a car that will be street driven a 2,000 miles a year and bracket raced 5 to 10 events a year. Engine will have to overcome some chassis short comings as the car has to be drive able on the street.

My guidelines for a naturally aspirated engine most likely would be as follows.
1. hydraulic roller cam (my thought is for low maintenance)
2. 11.0 to 1 compression ( Run on pump gas aluminum heads)
3. To use my current X block and 360-1 heads
4. I'm guessing at minimum I would need to purchase cam, lifters, pistons, for a naturally aspirated build.
5. Might consider adding 4.25 crank and new rods if there would be enough benefits to justify the addition cost

Can a 10.00 ET engine be built for a less than efficient street car chassis like this? I realize it is going to take a little extra power. I would be open to adding a little NOS to get it done if necessary but only in small shots like 100hp or so.

Also would consider a boosted type build using parts I have. I'm thinking a turbo blow through or a paxton/vortex style supercharger. Trying to keep a flat hood. But thinking the cost would probably kill this ideal. Although I could probably do the fabrication and pluming if I could come up with a proven combination.

Just thinking and maybe dreaming here a little any thoughts? Lets just say the motor is for my Dart 3,300 pounds, 4.10 gears 90/10 shocks in front and 275/60/15 drag radials in the rear.
 
Ok that was a lot of rambling last night on my part, guess I was tired. Lets make this simple.

I have the X block, 4" forged crank, 6.123 H beam rods, fully ported Indy 360-1 heads, TTI 1-7/8 W2 headers and want to put together a cool street strip motor. To keep cost down im thinking. solid lifter flat tappet cam. I'm going to have to buy cam, lifters, rockers, and pistons.

Motor must run on 91 pump gas and be street strip friendly. As I said above I would probably drive it about 2,000 miles a year and run 5 to 10 drag events a year. I would hope it would last at least 5 years before a rebuild.

So what cam specs and rockers ratio to take advantage of these heads. I was leaning towards about a 11 to 1 compresson. Or I could probably run a flat top at about a zero deck at about 11.5 to 1

What kind of reliable HP and TQ could I get out of this engine keeping the max RPM down in the 6500 to 7000 range?
 
Ok that was a lot of rambling last night on my part, guess I was tired. Lets make this simple.

I have the X block, 4" forged crank, 6.123 H beam rods, fully ported Indy 360-1 heads, TTI 1-7/8 W2 headers and want to put together a cool street strip motor. To keep cost down im thinking. solid lifter flat tappet cam. I'm going to have to buy cam, lifters, rockers, and pistons.

Motor must run on 91 pump gas and be street strip friendly. As I said above I would probably drive it about 2,000 miles a year and run 5 to 10 drag events a year. I would hope it would last at least 5 years before a rebuild.

So what cam specs and rockers ratio to take advantage of these heads. I was leaning towards about a 11 to 1 compresson. Or I could probably run a flat top at about a zero deck at about 11.5 to 1

What kind of reliable HP and TQ could I get out of this engine keeping the RPM down in the 6500 to 7000 range?

With our puke gas, 11:1 is not recommended. With 10.5:1, good solid FT cam, those heads, TD 1.7-1.6 rockers you should easily make 600HP. I did a similar engine a few years ago but with -2 cnc ported heads and it made 590 with a small 950HP carb and 610 with a dominator and 2" adapter but it was too high for the guys hood. And it was only 10:1.
Brian
 
With our puke gas, 11:1 is not recommended. With 10.5:1, good solid FT cam, those heads, TD 1.7-1.6 rockers you should easily make 600HP. I did a similar engine a few years ago but with -2 cnc ported heads and it made 590 with a small 950HP carb and 610 with a dominator and 2" adapter but it was too high for the guys hood. And it was only 10:1.
Brian

Alright then a 600hp naturally aspirated small block with a 100 to 200hp nitrous system that would be sweet. Especially if it fits under the stock hood. That 4 bolt main X block should handle that kind of power shouldn't it?
 
Just my opinion, but a roller cam will give you more power at just a bit more money especially if you already plan to buy lifters. I've talked to a few experienced guys locally to me and they recomend a hyd. roller for a street/strip type deal and a solid roller for more strip than street. They used to run solid tappet street engines, but you'll have to adjust your valves weekly. That said, I am looking forward to seeing what you end up doing.

And I agree with ou812...pump gas now isn't of the same quality as even a year or two ago let alone 15 years ago. 10.5:1 is a safe limit now
 
The blo knshould be bored o my to clean up the bore. The amount of extra cubes is minor and not worth it. The 4.25 stroke crank is nice, but since you already have a 4 inch arm, either use it or sell it and roll the money over into the 4.25.

IMO, use the roller cam even with a big roller, you'll not need to spin the mill high. The long stroke will make peak power sooner and I'd bet well below 7K RPM.
 
I like the ideal of a hydraulic roller to. I'm not sure what cam makes more power between a hydraulic roller and a solid flat tappet, guess I may check in to that and the pricing differences. I was talking to a buddy today about the solid lifter flat tappet cams. He was telling me they are laser cutting a oiling hole in lifters on some of these now. Guessing that is helping with some of the oil and cam issues we have been dealing with since the zinc elimination became a problem in our oil.
 
You will not like hyd. roller in this application. Solid roller would work great, but if we build it and dyno it, the flat tappet cam will work fine. Remember, 1.7-1.6 rockers so you'll get decent lift. Like I said, figure 575-600HP depending on the cam and other things like just how good the heads are, etc...

I'm changing out a hyd. roller setup in a SB Chevy for a local customer I had built an engine for. He street races for $$$ around here, and so far has not lost but he's over revved it hurting it multiple times. So stick with solid FT or solid roller IMO!
Brian
 
Listen as this is the truth! RPMS and hyd rollers are not the way to go without boat loads of $$$$$ and lots of spintron time.
 
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