There was a time not that long ago, when engine dynos were considered a black art. Not everyone believed what the dyno had to offer and some felt dynos were nothing more than hocus-pocus. Aren't you glad we don't live in those dark ages? Dynos are everywhere now and the reality of dyno racing has become an art form of its own. We thought it was about time to have our own dyno mule so to test any and every part imaginable just to see what would happen. So we built a 355cid Chevy and crowned it Danger Mouse (DM), in reference to the fact that it will be risking its life just to test any hair-brained idea we might come up with.

FROM THE BEGINNING
From the outset we knew DM would see a lot of abuse and we've logged close to 2,000 full-throttle dyno pulls, along with countless, unmeasured others, all without major breakage. Such reliability can be only attributed to one cause, the best parts. When building DM we stressed selection of the highest quality components to ensure a very long dyno life. The World Products 4-bolt Motown block and complete forged rotating assembly from Lunati have performed flawlessly, helping DM produce consistent results month after month after month, and we thank them for it.

Basically what we've learned in over 2 years of back-to-back testing is how to get a street small-block to produce anywhere from 300 to 700hp. All of it on pump gas, on a real world budget, and all with easy to find, off the shelf parts.

DYNO TESTS
Since no dyno test would be worth diddly without baseline power figures to compare to, the first test for DM found it equipped with the barest of bone-stock top end parts. A pair of reconditioned iron "Camel hump" heads (casting No. 461) from Powerhouse Engine Components breathed through a cast iron GM intake fueled by a professionally rebuilt Q-jet from the Carb Shop. After we felt we had a reliable stock baseline (Test 1) to compare figures to, we dove head-first into testing all sorts of cams, cylinder heads, carbs, rocker arms, spacers, headers, superchargers, EFI systems, and intake manifolds, because that's what we felt most of you would like to see. We've learned a lot from these tests and are sure we'll learn plenty more.

Note: You'll notice that some test numbers are missing from this story. With 36 documented dyno tests completed so far, we feel that the results of some of them just aren't worth taking up the limited space we have here, so we're leaving them out. Don't worry, the results in those tests were pretty boring anyways. Also, to keep testing accurate and the results repeatable, other than the parts listed, nothing else was changed and none of the parts were ever modified for each test

Test 1-Baseline:
Max 395 tq, 308 hp
Avg 376 tq, 266 hp
9.4:1 cr, No. 461 "Camel Hump" heads, COMP Cams 246PE cam (246/263 adv duration, 203/212 duration @ .050, .429/.438 valve lift, 110 Lobe separation), GM iron intake, Carb Shop Q-Jet, Proform HEI, Champion No.14 plugs, 91 octane, 37 degrees advance, 1 5/8-inch headers, 3-inch mufflers. This represents what a typical 355 cid small-block would make if it had just been blueprinted, but still used most of its stock components.

Test 2-New intake manifold:
Max 394 tq, 325 hp
Avg 380 tq, 270 hp
Installed a Weiand dual-plane intake manifold (PN 8004) and leaned out the Q-jet a bit. This netted us a 17hp gain.

Test 3-Roller-tip rockers:
Max 404 tq, 342 hp
Avg 390 tq, 278 hp
Replaced the stock stamped-steel rocker arms with COMP Cams Magnum 1.5:1 roller tip rockers, which gave us another substantial increase in power, raising peak hp by 17 and peak torque by 10. This pushed max tq over the 400 mark for the first time. Average hp and tq also improved over the stock baseline by a factor of 12 and 14 respectively.

Test 4-Retard cam:
Max 405 tq, 349 hp
Avg 390 tq, 278 hp
Retarded the cam 2 degrees, which added a little more peak power while averages stayed equal.

The next series of tests went a little deeper into the bolt-on field, but still kept swaps fairly simple. We made some improvements in torque this time, but horsepower gains were not that impressive.

Test 5-1 ?-inch headers:
Max 407 tq, 351 hp
Avg 388 tq, 287 hp
We installed larger 1-? Hooker headers. Compare tests 4 and 5 and you'll see that average torque was down by 2 lb-ft, but peak toque & horsepower were up slightly and average horsepower increased by 9. That's a fair trade to us.

Test 6-Full-roller rockers:
Max 407 tq, 351 hp
Avg 389 tq, 288 hp
Swapped COMP Cams 1.5:1 full roller aluminum rocker arms. Peak and average power increased by 1 each and we got 5 more lb-ft of torque at 3,200 rpm.

Test 7-XE256H cam:
Max 413 tq, 357 hp
Avg 396 tq, 293 hp
Swapped COMP Cams XE256H cam (256/268 adv duration, 212/218 duration @ .050, .447/.454 valve lift, 110 lobe separation) 2-degrees advanced and were rewarded with lots more grunt.

While the Q-jet carb had been working ok until now, we wanted to test a Speed Demon carb on a new Edelbrock Performer RPM "Air Gap" manifold. We also bumped up to the next size larger COMP Cams Xtreme Energy camshaft. The final reward was a new max 386 hp and 438 lb-ft of torque with new averages at 316hp/416tq. So now, we had this stock iron-headed 355 Mouse making almost 390hp and 440 lb-ft of torque! This was definitely the best power formula with the stock heads, particularly since the motor didn't respond very well to the bigger XE262H cam in Test 12. We took that as a sign that we had just about maxed out the stock cylinder head's flow potential and would either have to go in to start porting and polishing, or install a new set of performance cylinder heads for more power.

Test 9- Speed Demon 750 carb:
Max 418 tq, 356 hp
Avg 398 tq, 294 hp
Installed Speed Demon 750 and picked up torque and horsepower all around.

Test 10-"Air gap" manifold:
Max 438 tq, 380 hp
Avg 416 tq, 315 hp
Installed Edelbrock Performer RPM "Air Gap" intake manifold, which was the best single-gain swap yet and the first test to average well over 400 lb-ft of torque.

Test 12-XE262H cam:
Max 438 tq, 386 hp
Avg 416 tq, 316 hp
Swapped in larger COMP Cams XE262H cam (262/270 adv duration, 218/224 duration @ .050, .462/.469 valve lift, 110 lobe separation) straight up and low-end power began to fall.

THE GENERAL'S PARTS
Dm needed some new heads and for our next set, we went to GM Performance Parts (GMPP) and got a set of iron Vortec castings. When compared to the stock "Camel hump" heads, the Vortec's actually dropped DM's compression by about ?-point to 9.25:1, but that didn't stop them from making 23 more horsepower. After that, we swapped also on our first set of 1.6:1 ratio rockers and were again rewarded with more power

Test 14-GMPP Vortec heads:
Max 435 tq, 409 hp
Avg 413 tq, 330 hp
Installed GMPP Vortec iron heads (Scoggin-Dickey Performance Center PN SD8060A: 64cc chambers, 170cc intake runner volume, 1.94/1.50 valves), COMP 1.5:1 Magnum roller tip rockers, and Edelbrock Performer RPM "Air Gap" manifold and made lots of extra power.

Test 15-COMP 1.6:1 rockers:
Max 440 tq, 416 hp
Avg 417 tq, 333 hp
Installed COMP 1.6:1 Magnum roller tip rockers, which further pushed the power curve up.

ROCKERS AND BIGGER CAMS
There's a lot of power to be found in rocker arms and camshafts and in that pursuit, we forged onward, testing yet another bigger cam and we swapped rocker arms until we were blue in the face.

Test 17-COMP 1.6/1.5 rockers:
Max 442 tq, 414 hp
Avg 419 tq, 335 hp
We wrestled rocker arm ratios around for quite a while and found that 1.6:1 ratio intake and 1.5:1 ratio exhaust were the best combination of all rockers tested until that point. They gave a torque improvement with no hp loss. Looking back now, Test 17 may have been the best overall combination of power and torque. Especially considering that these parts are all still low on the cost scale.

Test 18-XE268H cam:
Max 439 tq, 427 hp
Avg 418 tq, 335 hp
Next in went the next bigger COMP cam and we changed all rockers back to 1.6:1. We got the results we were expecting, more horsepower upstairs and less torque downstairs. We also tried this cam with the 1.6/1.5 rocker swap and got less power. (XE268H = 268/280 adv, 224/230 @ .050, .477/.480 lift, 110 LS)

BLOWING FORWARD
After the strong normally aspirated baseline had been established, we began our long quest to build the most power possible on pump gas by first using a small Weiand supercharger. This little two-lobe blower made our 355 think it was a 502! Beginning with Test 19 we also installed our first set of aluminum heads too. The Trick Flow Specialties (TFS) castings lowered DM's compression to a more blower-friendly 8.5:1 and gave us some extra breathing room with their large ports. To see how much power the blower would add, we baselined the engine with the TFS heads, Air Gap manifold, Demon carb, and a new COMP Cams NX flat-tappet hydraulic camshaft first (Test 19), then bolted on the blower (Test 20).

Test 19-Unblown:
Max 434 tq, 444 hp
Avg 401 tq, 340 hp
8.5:1 cr, TFS heads (Summit Racing PN TFS-30400013-CNC, 72cc chambers, 195cc runners, 2.02/1.60 valves), Edelbrock RPM Air-Gap manifold, COMP NX274H camshaft (274/292 adv dur, 230/244 dur @ .050, .487/.501 lift, 113 LS). COMP Cams 1.6:1 roller rockers. The lower compression and large camshaft didn't seem to hurt too much. In fact, it had some serious top end pull making 444hp at 6100 rpm. Low-end torque fell off, but we expected that since we were running a big cam combined with very low compression.

Test 20-Weiand blower:
Max 574 tq, 602 hp
Avg 539 tq, 462 hp
Installed the 177ci Weiand Pro-Street mini-blower, Holley HP950 supercharger carb out of the box, 36 degrees total advance, 100-octane unleaded pump gas and a can of octane booster. We offered a warm welcome to Mr. 600hp on this pull!

EFI TESTS
Right after the blower tests were completed we moved to electronic fuel injection. We heard that Edelbrock was making a new EFI manifold based on its Victor E casting and thought it would be a perfect match for the a F.A.S.T. EFI system we'd wanted to run. But, like always, we had to know how much power the engine would make with a goo-ol' carb first. So we equipped DM with a prototype COMP Cams EFI hydraulic roller camshaft and a Speed Demon 750 carb with corks plugging the fuel injector bosses and made a pull (Test 21).

Test 21-Carb baseline:
Max 430 tq, 474 hp
Avg 397 tq, 330 hp
TFS aluminum heads, Edelbrock Victor EFI manifold, COMP Xtreme Energy EFI prototype HR camshaft (281/288 adv dur, 230/236 dur @ .050, .544/.555 lift w/1.6 rockers, 113 LS). COMP 1.6:1 roller rockers, Speed Demon 750 carb, 36 degrees total advance. When compared to previous normally aspirated Test 19, DM's horsepower went through the roof! Peak jumped by 30 to an outstanding 474hp but torque fell off down low, so the extra power wasn't a freebie. COMP attributes the low-end losses to the more-aggressive ramp profiles on the NX274 hydraulic cam used back in Test 19. The hydraulic roller cam in Test 21 really begins to take over at higher rpm due to its reduced frictional losses.

Test 22-F.A.S.T. EFI w/ 30 lb./hr. injectors @ 50 psi:
Max 431 tq, 480 hp
Avg 400 tq, 332 hp
Installed the EFI system with Accufab throttle body and right away the EFI proved its superiority by bringing low-end torque back up and increasing top-end power to 480hp. Although power dropped slightly in the mid-range, which we think we could've recovered with some more tuning time.

REBUILD, REPAIR, AND RE-TEST
Throughout all this we've learned that no matter how tough you build an engine, there comes a time when it will need to rest. So after Test 22 DM went back into the shop for a complete overhaul by the technicians at Speed-O-Motive and came out equipped with some new bottom-end components ready for battle. The first series of tests following the rebuild were pretty uneventful and mostly confirmed that the rebuild did not cost any power. Besides, we wanted to go in a different direction with this rebuild and test some more low-end power making products because we felt DM was already getting too far out of reach for many. So you'll note that power is way down compare to Tests 21-22.

Test 29-Freshly rebuilt with some new components:
Max 415 tq, 399 hp
Avg 397 tq, 316 hp
Installed World Products Sportsman II angle-plug iron heads (64cc chambers, 200cc runners, 2.02 intake valves, 1.60 exhaust valves) @ 10:1compression, Holley dual-plane intake manifold, HP750 carb, Lunati hydraulic roller cam (215/224 @ .050, 268/279 adv, .489 lift, 112 LS), COMP 1.6:1 roller rockers. Also note: the following tests were done at a different dyno facility, so the results are not quite comparable to previous tests.

SUPERPOWER!
Immediately following our less than exciting low-end power building exercise, we got our hands on one of ATI 's Procharger D-1SC centrifugal superchargers, which definitely gave us the "most power on pump gas" yet. For the blower bash our champions of the dyno and wrench, Speed-O-Motive, also dove back into DM's storage locker and pulled out the same old set of TFS aluminum heads we'd ran before. Speed-O also installed a new Crane Cams hydraulic roller with lots of lift and duration and then they topped it all off with an ACCEL GEN VII DFI system for the utmost in tunability. You may also note that compression is up slightly when compared to the other blower tests using the TFS heads, (Tests 19-20). That's because during the rebuild, Speed-O-Motive installed a new set of Lunati flattop pistons with a taller compression height, moving the piston top higher up the bore for a true "zero" deck. Previously, the old pistons were installed about .040-inch below the deck to better simulate what might really be under you hood. But, by this time we wanted to truly optimize everything.

Test 31-Unblown:
Max 424 tq, 466 hp
Avg 393 tq, 333 hp
9.1:1 cr, TFS aluminum heads, Accel Gen VII DFI w/ 55 lb/hr, Crane Cams HR camshaft (240/248 @ .050", 306 /314 adv, .595 lift, 114 LS), COMP 1.6:1 rockers. Left the blower belt and induction plumbing off to baseline DM without any boost.

Test 32-ATI blower:
Max 613 tq, 697 hp
Avg 545 tq, 471 hp
Installed ATI Procharger D-1SC centrifugal supercharger with 4.25" pulley and got 697hp and 613 lb-ft of torque, all on 91-octane pump gas.

OLD FASHIONED POWER
Right after the blower test we moved back to making power the old-fashioned way, on the motor, and got this little beast up to some pretty big power figures.

Test 34-Vic Jr. heads, COMP XR280R cam:
Max 441 tq, 504 hp
Avg 404 tq, 359 hp
Next we tried Edelbrock's Victor Jr. heads @ 10:1cr, (64cc chambers, 215cc runners, 2.08" intake valves, 1.60" exhaust valves), with a Vic Jr. manifold and one of COMP's Xtreme Energy Street Roller camshafts (242/248 @ .050, 280/286 adv, .600/.606 lift w/ COMP 1.6:1 rockers, 110 LS), and a 650cfm Mighty Demon 650 carb. The results were 504hp and 441 lb-ft tq!

Test 35-Total Seal rings:
Max 453 tq, 497 hp
Avg 413 tq, 366 hp
This one was all about sealing. Total Seals' gapless top rings were installed and power and torque was increased up to 6,000 rpm. Average figures also climbed as well and some more tuning time probably would have gained us back the top-end power we lost.

THE BIGGEST AND BADDEST YET
The last tests got us thinking that bigger could truly be better. So, after acquiring an Edelbrock Super Victor manifold with an even larger COMP roller, we went back to see if we could break the 550hp barrier. Well...DM certainly made more power than it did the month before, but the results were a far cry from spectacular. After swapping the cam, intake, and carburetor, we saw an 11hp peak increase and 2 lb-ft of extra peak torque. While we're certainly not putting it down, for the time, effort, and expense of the swap the results were not worth it in our minds. All that means is that we've pretty much hit the wall with the current parts combination and just like on the street, throwing bigger parts at it won't make it go any faster. So we're rethinking our strategy and planning some cool stuff for DM's future. We're confident we'll see close to 600 N.A. horsepower soon, and still on pump gas too. One thing we know is that it won't be easy. But, it'll sure be fun!

Test 36-Super Vic, COMP XR286R cam:
Max 455 tq, 508 hp
Avg 420 tq, 365 hp
Swapped Edelbrock Super Victor manifold and COMP XR286R solid roller camshaft (248/254 @ .050, 286/292 adv, .606/.612 lift w/ COMP 1.6:1 rockers, 110 LS), Holley HP1000 carb, 38 degrees advance.

Test 1 Stock BaselineTest 2 Weiand 8004Test 3 COMP 1.5 rockersTest 4 Retard cam -2 degrees
RPMTQHPTQHPTQHPTQHP
2600389193384190385190379188
2800385205381203382203377201
3000388222384219389222384219
3200395241391238396241395241
3400393255391253399258398257
3600393270394270402276401275
3800389282394285404292405293
4000383292390297404307403307
4200374299384307398318398319
4400363304375314391327395331
4600351307367322384336388340
4800337308354324374342380347
5000322306339323356339366349
Max395308394325404342405349
Avg376266380270390278390278
Test 5 ? HeadersTest 6 Full roller 1.5 rockersTest 7 COMP XE256H
RPMTQHPTQHPTQHP
2600377187380188387191
2800381203382204394210
3000390222391223401229
3200396241401244411250
3400400260403261413267
3600403276405277413283
3800407294406294413298
4000405308407310412314
4200401321402322406325
4400395331367332402337
4600387339388340394345
4800380347380347385352
5000368350368350375357
5200354350353349348354
5400N/AN/A339349348357
5600N/AN/AN/AN/A334356
Max407351407351413357
Avg388287389288396293
Test 9 Speed Demon 750Test 10 Air Gap intakeTest 12 COMP XE262H
RPMTQHPTQHPTQHP
2600393194411203396196
2800395211413220404215
3000403230420240416237
3200413252430262429261
3400416269436282429278
3600415284438300435298
3800416301437316437316
4000414315437333438334
4200408327435348436348
4400402337429359432362
4600394345421369424371
4800386352411376417381
5000373356398379405386
5200359355380376389385
5400346356365375375386
5600331353347370360384
Max418356438380438386
Avg398294416315416316
Test 14 Vortec headsTest 15 COMP 1.6 rockers
RPMTQHPTQHP
2600383190379188
2800389208384204
3000406232404231
3200422257427260
3400429278433280
3600431295435298
3800429311437316
4000426325432329
4200425340433347
4400430361434364
4600433379439385
4800430393433396
5000421400423402
5200406402411407
5400395406401413
5600384409389415
5800365403365403
Max435409440416
Avg413330417333
Test 17 1.6I/1.5E rockersTest 18 COMP XE268H
RPMTQHPTQHP
2600384190371184
2800392209379202
3000413236400229
3200428261425259
3400432280431279
3600437299436299
3800439317435315
4000439335430328
4200437350431344
4400438367439367
4600441387437383
4800435398438400
5000425405429408
5200413409417413
5400401412407419
5600388414398424
5800366404387427
Max442414439427
Avg419335418335
Test 19 UnblownTest 20 Blown
RPMTQHPTQHP
2600358177490243
2800363193500266
3000382218514293
3200414252526320
3400417270543352
3600417286555380
3800415300557403
4000413315561427
4200413330567453
4400418351568475
4600434380571500
4800425389571521
5000412392564537
5200408404560554
5400407419558573
5600405432547583
5800399441532588
6000384439518592
6200374441508600
6400356434494602
Max434444574602
Avg401340539462
Test 21 CarbTest 22 EFI 30lb/hr
RPMTQHPTQHP
2600352174364180
2800350187362193
3000357204369211
3200379231383233
3400389252387251
3600385264385264
3800385278381276
4000384292379289
4200387309388310
4400406340408342
4600424372421369
4800428392427391
5000429408426405
5200430426426422
5400421433431444
5600424452423451
5800420464420464
6000413471420480
Max430474431480
Avg397330400332
Test 29 Rebuilt
RPMTQHP
2600362179
2800385205
3000401229
3200410250
3400411266
3600412282
3800410297
4000415316
4200415332
4400412345
4600407356
4800402368
5000398379
5200389385
5400380391
5600374399
5800358395
Max415399
Avg397316
Test 31 UnblownTest 32 BlownTest 33 Boost
RPMTQHPTQHP(PSI)
26003161563881922.5
28003461844152212.9
30003642084392513.2
32003842304622823.9
34003842484823124.4
36003852645003435.0
38003832775203775.4
40003883955454155.8
42003983195684546.5
44004043385834897.4
46004053555975238.1
48004113756095578.9
50004203996115829.7
520042441960760110.4
540042343661262911.3
560041944761365312.2
580041345661367713.0
600040546260669213.8
620039546659169714.7
Max424466613697 14.7
Avg3933335454717.8
Test 34 StandardTest 35 Gapless
RPMTQHPTQHP
2600345171352175
2800362193373199
3000371212384220
3200374228387236
3400374242381247
3600387265389266
3800398288403291
4000396302405309
4200393314407326
4400402337416349
4600415364430376
4800428391440402
5000435414448427
5200440436452448
5400441453453466
5600439468450479
5800433478444490
6000428489435496
6200420496420495
6400412502407496
6600401504398494
Max441504453497
Avg404359413366
Test 36 Cam, Manifold
RPMTQHP
2600353175
2800375200
3000390223
3200393239
3400388251
3600395271
3800407294
4000416316
4200421336
4400428359
4600437383
4800448409
5000454432
5200455451
5400453466
5600452482
5800450497
6000443506
6200430508
6400416507
Max455508
Avg420365
SOURCE
ACCEL Performance Products
10601 Memphis Ave. #12
Cleveland
OH  44144
FUEL, AIR, SPARK, TECHNOLOGY (F.A.S.T.)
151 Industrial Dr., Dept. SC
Ashland, MS 38603
Accessible Technologies, Inc. (ATI Procharger)
14801 W. 114th Terr.
Dept. SC
Lenexa, KS 66215
Holley Performance Products(Source for: Holley and Lunati products)
1801 Russellville Rd., Dept. EM
Bowling Green
KY  42102
Accufab
1516 E. Francis St.
Ontario
CA  91761
909-930-1751
www.accufabracing.com
Mr. Gasket Company
10601 Memphis Ave., #12
Cleveland
OH  44144
216-688-8300
www.mr-gasket.com
Bill Mitchell Hardcore Racing Products (Source for: World Products)
51 Trade Zone Ct.
Dept. SC
(631) 737-0372
Powerhouse Engine Components (Source for Camel Hump cylinder heads)
931 19th St, Dept. EM
Bakersfield
CA  93301
Carb Shop
Ontario
CA
9-09/-947-3575
customcarbs.com
Scoggin-Dickey Chevrolet (Source for GMPP parts)
5901 Spur 327, Dept. EM
Lubbock
TX  79424
COMP Cams Speed-O-Motive
131 W. Lang Ave.
West Covina
CA  91790
6-26/-869-0270
speedomotive.com
Demon Carburetion
Dahlonega
Ge
7-06/-864-8544
barrygrant.com
Summit Racing Equipment (Source for: TFS heads)
P.O. Box 909, Dept. EM
Akron
OH  44309
Edelbrock
Dept. 5.0
2700 California St.
Torrance
CA  90503
310-781-2222
www.edelbrock.com
Westech Performance Group
11098 Venture Dr., Unit C
Mira Loma
CA  91752
9-09/-685-4767
www.westechperformance.com
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