This test compares the Holley StealthRam (HSR) fuel injection intake, with a Holley Stealth Single-Plane EFI intake (SP). The engine was basically the same, consisting of a ZZ4 crate motor, AFR190 heads, LT4 HOT cam, and SLP 1-3/4" SS headers. Trans is a 700r4 with a Vigilante 2800 stall converter. The Engine Control Module (ECM) was a '92 TPI stock ECM (MAP/speed-density) with a modified EPROM.
A similar intake comparison was performed in the October2002 issue of CarCraft. Their longblock consisted of a 355 with a flat-tappet 225/235 cam and Holley aluminim heads. Their tests showed almost indistinguishable differences between the Single-plane MPFI and StealthRam. They did use a 4bbl type 1000cfm throttlebody. Their motor only made 400hp on the engine dyno, so the differences between the intakes may not be highlighted until more power is available in the longblock?? The DynoJet Dyno is located at: New German Performance 1615 Perryman Road Aberdeen, 21001 Tel. 410-994-0000 http://www.ngpracing.com/| SP | HSR | SP |
HSR |
||||
| RPM | Torque | Torque | Diff. | HP | HP |
Diff.
|
|
|
3400
|
357
|
334
|
13
|
|
231
|
216
|
15
|
|
3600
|
354
|
346
|
8
|
|
242
|
237
|
5
|
|
3800
|
352
|
351
|
1
|
|
252
|
254
|
-2
|
|
4000
|
343
|
352
|
-9
|
|
261
|
268
|
-7
|
|
4200
|
334
|
350
|
-16
|
|
267
|
280
|
-13
|
|
4400
|
326
|
345
|
-19
|
|
273
|
290
|
-17
|
|
4600
|
317
|
339
|
-22
|
|
278
|
297
|
-19
|
|
4800
|
308
|
331
|
-23
|
|
282
|
303
|
-21
|
|
5000
|
301
|
322
|
-21
|
|
287
|
307
|
-20
|
|
5200
|
298
|
316
|
-18
|
|
295
|
313
|
-18
|
|
5400
|
293
|
310
|
-17
|
|
301
|
319
|
-18
|
|
5600
|
288
|
304
|
-16
|
|
307
|
324
|
-17
|
|
5800
|
283
|
299
|
-16
|
|
312
|
330
|
-18
|
|
6000
|
276
|
292
|
-16
|
|
315
|
335
|
-20
|
|
6200
|
269
|
287
|
-18
|
|
318
|
339
|
-21
|
|
6400
|
260
|
280
|
-20
|
|
322
|
342
|
-20
|
|
6600
|
254
|
270
|
-16
|
|
320
|
340
|
-20
|
|
AVG
|
310
|
328
|
-15
|
|
289
|
294
|
-15 |
| HSR | Diff. over HSR | SP | ||||
| Temp |
54
|
~55 |
||||
| Humidity | 94% |
|||||
| Baro | 32.25 |
|||||
| R/T | 0.465 | 0.008 |
||||
| 60' | 1.646 | -0.051 | 1.697 |
|||
| 330' | 4.823 | -0.075 | 4.898 |
|||
| 1/8 | 7.516 | -0.100 | 7.616 |
|||
| Mph | 90.81 | -0.89 | 89.92 |
|||
| 1000' | 9.857 | -0.121 | 9.978 |
|||
| 1/4 | 11.833 | -0.166 | 11.969 |
|||
| Mph | 114.30 | -0.80 | 113.50 |
1/4-mile Run
Click HERE for a short video of the Fuel-pressure guage taken during the dyno run
The Singleplane intake was topped with an Accel/Lingenfelter plenum adaptor elbow (p/n 74882), which unfortunately is no longer in production.
