[ez2cdave]

To All,

This is my first post to this Forum and I am dead serious in my search for information . . . I am 45 and have been away from Hot-Rodding since 1990, but am no stranger to the Hobby . . . ;-)

I am looking to build a fuel-injected, stroker SBC to drop into a 1989 IROC-Z (Car will retain PS, PB, A/C, etc ), mainly for Street-Driving, but it will see the Dragstrip every now and then, too . . . Transmission will be a 4L80E (Converter to be determined) . . . Rear Axle to be either 12-Bolt Chevy or 9" Ford, Hydraulic Roller Camshaft & Gears will be selected, based on Combination Requirements.

I am aware of the 383 vs 406 Arguments . . . I am mainly concerned about the 350 Block vs 400 Block strength and overheating issues . . . I do not want to overbore more than .030", if at all possible . . . HOWEVER, let me introduce the combos I am considering:

383 cid - (350 Block) 4.030" Bore X 3.750" Stroke - 5.7" Rods
406 cid - (400 Block) 4.155" Bore X 3.750" Stroke - 5.7" Rods
409 cid - (350 Block) 4.030" Bore X 4.000" Stroke - 6.0" Rods
428 cid - (400 Block) 4.125" Bore X 4.000" Stroke - 5.7" or 6.0" Rods
434 cid - (400 Block) 4.155" Bore X 4.000" Stroke - 5.7" or 6.0" Rods

Desired Compression Ratio - 9.5 -10.5 (nominal for 93 Octane)
Edelbrock Pro-Flo RPM Fuel Injection (resize Injectors, as required)
Hydraulic Roller Cam (Broad Torque Range)
Cylinder Heads (most likely Aluminum, Runner CC Volume, to be determined)
Etc, Etc, Etc . . .

That 409 really has my attention . . .

There are some parameters to help get things started . . . I am looking forward to your input and suggestions !

Dave Fitch
Louisburg, NC

[squeeezer]

i have a rescent build...(only 450 miles )
might interest you
406=11 to 1 compression...(hates race fuel-92 octane)
511 400 block yes they are strong enough
comp cams xtreme 290 grind FLAT SOLID....YOU COULD IMPROVE APON
trick flow medium port heads=195 cc.....$1000 worth of porting

527.7 horse all in by 6100 rpm
515 tq @4700 rpm 111volumetric efficiency

this is a street motor that idles @ 980 rpm @ 10 in/hg brakes work great

here is the part youll love
its in a 91 camaro rs 5 speed though .....you may want a whopping 3000 stall

contact me if you want more info

[tornado-tech]

What about the 3.875 stroke crankshaft? Overheating in a 400 is not that common. My previous 400 bored .0040 in a 511 block did not do this and
I run my motors very hard. Highest temperature was 195 degrees and this was the highest it ever was and this included driving the vehicle back from an event. I ran the Comp XR282 in this and had 15" vacuum at idle also for a comparison.

[bracketeer]

My 350 ran so hot I had to remove the thermostat. I built a 400 and I had to instal a thermostat to keep it up to temp. Make sure the water holes in the head gasket line up with the holes on the head and the block.

[steveyb4342]

Correct me if Im wrong but I believe a 350 with 3.875 stroke bored 0.030 over is a 396. For that kind of stroke {especially 4" } the clearancing that would have to be done would be wild.

Steve

[ez2cdave]

To All,

The 3.875" Stroke looks very interesting . . . Found this about the Lingenfelter 420 and other motors . . . I like that 2nd 420 motor (COMBO #2) . . . No 3000 RPM Torque Converter need there ! ! !

************************************************** ********
COMBO #1

420 Cubic Inches: L98 motor
Lingenfelter 420, from his book- Modifying Small Block Chevy Engines.
3.875" stroke Callies crank
Oliver 5.875" rods
11: 1 compression, custom forged pistons.
Used a Bowtie engine block
Comp Cams mechanical roller cam: 236/244 @ .050, .549/.549 lift, 110 deg lobe sep, 1.5 roller rocker arms by Comp Cams.
Lingenfelter ported AFR 190 aluminum heads
SuperRam intake, base, and 58mm throttle body, controlled by DFI using 36lb/hr injectors.

Ran test on 1-7/8" open headers.

RPM TQ HP
1600 407 124
2000 415 158
2500 478 228
3000 484 277
3500 515 343
4000 534 407
4500 543 465
5000 530 505
5500 498 525
5750 460 508

As you can see from the numbers above, the motor is a torque monster. The combination of the large displacement, smallish heads, high lift roller cam, and the intake system make big block torque in a small block package. This motor computes out to a 113% efficiency at the HP peak, which is an indication of how well matched this combo is.

************************************************** ********

420 Cubic Inches: L98 motor
Lingenfelter 420, from Hi Tech Performance May, 1996
3.875" stroke Lunati 4340 forged steel crank
Oliver 5.875" rods
11: 1 compression, JE custom forged pistons.
Used a Bowtie engine block
Lingenfelter hydraulic roller cam: 219/219 @ .050, .525/.525 lift. 112deg lobe sep, Comp Cams 1.6 ratio stainless steel rocker arms.
Lingenfelter CNC ported Brodix Track I heads, 67cc chambers
SuperRam intake, base, and 58mm throttle body, controlled by DFI using 30lb/hr injectors.

Ran test with Accel 1-3/4" headers.

RPM TQ HP
2000 435 165
2500 470 225
3000 520 300
3500 545 365
4000 560 420
4400 561 480
5000 535 502
5200 507 509
5500 475 490

As you can see from the numbers above, the motor is a torque monster. The combination of the large displacement, smallish heads, high lift roller cam, and the intake system make big block torque in a small block package. You can see the differences in the torque and power curves compared to the other 420 motor by Lingenfelter. Even though the engines use the same displacement, intake, and internals; the cam, heads, and injectors are different.

************************************************** ******

WHAT DO YOU GUYS THINK ???

Dave Fitch
Louisburg, NC

[Koolaid]

Dave,

Both of those combos are built around a Bowtie block. Are you trying to stick with a stock block or is aftermarket a possibility?

[ez2cdave]

Originally Posted by Koolaid

Dave,

Both of those combos are built around a Bowtie block. Are you trying to stick with a stock block or is aftermarket a possibility?

************************************************** ********

KOOLAID & All,

Yes, an Aftermarket Block is a possibility !

Here is the situation I am starting with . . .

Picture a 1989 IROC-Z (No T-Tops) . . .

Remove the Engine, Transmission, and Rear Axle and deposit them in the nearest dumpster of your choice (LOL!) . . .

Now install a "Stroker" Small-Block (409, 420, etc) with Aftermarket Fuel Injection (I just discovered the "MASS-FLO" System and want to learn more !) . . . Hydraulic Roller Cam (Broad, Flat, Torque Curve 5500-6000 Max. RPM) . . . Compression 9.5 - 11.0 :1 (93 Octane Friendly) . . .

Transmission time . . . 4L80E with "Stand-Alone Controller" . . . 2.48 First Gear like a TH400 or optional 2.75 Low First Gear . . . AVOID High-Stall Converter, if possible . . .

Rear Axle . . . "POSI", of course . . 12-Bolt Chevrolet or 9" Ford . . . Gears dependent upon Motor Combination . . .

NONE of the original GM CPU System will be reused, if at all possible . . .

"Get the Picture ?"

Everyone's thoughts are welcome ! ! !

Dave Fitch
Louisburg, NC

[steveyb4342]

I dont understand. How much does the block have to be bored to get 420cu in? How does that all equal 420? Someone help me out here please.

Steve

[ez2cdave]

Originally Posted by steveyb4342

I dont understand. How much does the block have to be bored to get 420cu in? How does that all equal 420? Someone help me out here please.

Steve

************************************************** ********

Steve & All,

First of all, your question . . . A 3.875" Stroke is combined with a 4.155" Bore to yield 420 cid (421 actually) . . . In the two previous examples, a Bowtie Block was used, which I am sure led to the confusion if you were thinking of a standard 350 Block . . .

************************************************** ********

NOW . . . Check out these "BULLETS" , Guys ! ! !

http://www.shafiroff.com/

http://www.shafiroff.com/shortblocks/406_shortblock.asp

http://www.ultrastreet.net/434_realstreet.asp

WOO-HOO ! ! !

Dave Fitch
Louisburg, NC

[steveyb4342]

OHHH ok. Yes it was the bowtie block that sent me for a loop. Sorry about that I should have caught on. What would be the biggest displacement you could make from a standard 350 block? Is 4" stroke in a standard block even possible? The biggest I know of is the 396. 3.875 by 4.030, unless of course you went 4.060 or something.

Thanks Steve

[ez2cdave]

Check out these "BULLETS" , Guys ! ! !

http://www.shafiroff.com/

http://www.shafiroff.com/shortblocks/406_shortblock.asp

http://www.ultrastreet.net/434_realstreet.asp

WHAT DO YOU GUYS THINK ???

Dave Fitch
Louisburg, NC