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.

 

RPM	TQ	HP
2600	362	179
2800	385	205
3000	401	229
3200	410	250
3400	411	266
3600	412	282
3800	410	297
4000	415	316
4200	415	332
4400	412	345
4600	407	356
4800	402	368
5000	398	379
5200	389	385
5400	380	391
5600	374	399
5800	358	395
Max	415	399
Avg	397	316

We've tried to match top end packages based on performance and found a lot of power in heads and intakes as well.

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.

	Test 31 Unblown		Test 32 Blown		Test 33 Boost
RPM	TQ	HP	TQ	HP	(PSI)
2600	316	156	388	192	2.5
2800	346	184	415	221	2.9
3000	364	208	439	251	3.2
3200	384	230	462	282	3.9
3400	384	248	482	312	4.4
3600	385	264	500	343	5.0
3800	383	277	520	377	5.4
4000	388	395	545	415	5.8
4200	398	319	568	454	6.5
4400	404	338	583	489	7.4
4600	405	355	597	523	8.1
4800	411	375	609	557	8.9
5000	420	399	611	582	9.7
5200	424	419	607	601	10.4
5400	423	436	612	629	11.3
5600	419	447	613	653	12.2
5800	413	456	613	677	13.0
6000	405	462	606	692	13.8
6200	395	466	591	697	14.7
Max	424	466	613	697	14.7
Avg	393	333	545	471	7.8

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.

Blowers have been a healthy part of Danger Mouse's diet. With this street-legal ATI Procharger making just shy of 700hp on 91-octane!

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!

JUMPING FORWARD
After the baseline had been established, we began our long quest to build the most power possible using nothing but off the shelf parts. We created perfection in several categories; one of which was supercharged with what we like to think of as the "most power on pump gas". In order to meet the pump gas challenge we had set forth for ourselves, we opted to install a small (177ci) Roots-style Weiand supercharger. This little two-lobe blower sits on top of a cast-aluminum Weiand intake manifold and pumps more air into the engine than it could normally breath in giving it the power-producing capacity of a much larger displacement engine. In other words, it kinda turns a 350 into a 502. But, installing a blower is not a task one should take lightly. It's a serious jump in performance and there are several key precautions one must take to ensure your blown engine doesn't blow. Beginning with T19 we installed a set of aluminum Trick Flow Specialties (TFS) cylinder heads to lower DM's compression to a more blower-friendly 8.5:1. The new heads also gave us some extra airflow flow capacity with their big intake ports. We baselined the engine with the TFS heads, an Edelbrock Performer RPM Air Gap manifold and Demon carb, and a COMP Cams hydraulic blower camshaft to see how it would compare blown to unblown.

Here are the unblown specs for DM. T19: TFS aluminum heads (Summit Racing PN TFS-30400013-CNC, 72cc chambers, 195cc runners, 2.02/1.60 valves), TFS pushrods (Summit PN TFS-21407850), Edelbrock RPM Air-Gap manifold, COMP Cams NX274H camshaft (274/292 advance duration, 230/244 duration at .050, .487/.501 lift, 113 LS) straight up. COMP Cams 1.6:1 Pro Magnum roller rockers. The lower compression and large camshaft didn't seem to hurt DM that much. In fact, it had some serious top end pull with 444 hp at 6,100 rpm. Low-end torque fell off, but we expected that since we were running a pretty big cam combined with very low compression. But once we added the blower and made a few tuning tricks, DM came alive with over 600 hp! All 600 ponies were made on 100-octane unleaded pump gas from 76 Racing.

Here are the specs from the best supercharged test for DM. T20: Weiand 177ci mini-blower with 3.07-inch top pulley and 7-inch bottom pulley (228-percent overdrive). Peak 10.3-psi boost at 6,500 rpm, 36 degrees total advance, Holley 950HP supercharger carb, 100-octane unleaded 76 Racing pump gas and NOS octane booster.

	T19	T19	T20	T20
RPM	TQ	HP	TQ	HP
2600	358	177	490	243
2800	363	193	500	266
3000	382	218	514	293
3200	414	252	526	320
3400	417	270	543	352
3600	417	286	555	380
3800	415	300	557	403
4000	413	315	561	427
4200	413	330	567	453
4400	418	351	568	475
4600	434*	380	571	500
4800	425	389	571	521
5000	412	392	564	537
5200	408	404	560	554
5400	407	419	558	573
5600	405	432	547	583
5800	399	441	532	588
6000	384	439	518	592
6200	374	441	508	600
6400	356	434	494	602*
Max	434	444	574	602
Avg	401	340	539	462

EFI TESTS
Right after the blower tests were completed, we moved onto fuel injection. We learned that Edelbrock was making a new EFI manifold based on its outstanding Victor E casting and thought this would be a perfect match for the new F.A.S.T. EFI system we wanted to try out, but we had to know how much power the engine would make with a carb first. So to get those results, we equipped DM with a prototype COMP Cams EFI hydraulic roller camshaft and a Speed Demon 750 carb sitting on top of the new Edelbrock Victor EFI manifold with corks plugging the fuel injector bosses.

T21: same TFS aluminum heads, Edelbrock Victor EFI manifold (PN 29785), COMP Cams Xtreme Energy EFI prototype hydraulic roller camshaft (281/288 advance duration, 230/236 duration at .050, .544/.555 lift with 1.6 rockers, 113 LS) straight up. COMP Cams 1.6:1 Pro Magnum roller rockers, Speed Demon 750 carb, 36 degrees total advance.

When compared to previous normally aspirated T19, DM's horsepower went through the roof with the new components in T21! Peak power jumped by 30 hp to an outstanding 474 hp at 6,100 rpm but torque fell off down low, so the extra power wasn't a freebie. COMP Cams attributes this to the more-aggressive low-lift ramp profile on the NX274 flat-tappet hydraulic camshaft. The hydraulic roller cam really begins to take over at higher rpms due to its reduced frictional losses. Now it was time to test the EFI set-up.

T22: Installed F.A.S.T. EFI system with Accufab throttle body and 30 lb-hr injectors at 50 psi. Right away the EFI proved its superiority by adding torque down low and increasing power up top. Although power dropped slightly in the mid-range, which we think we could've got back with more tuning time. We also thought DM might have been a little starved for fuel with small the 30 lb-hr injectors we had originally installed, so we switched them to larger 36 lb-hr injectors and got just a little more top end power, but low end went back down, so we put the 30 pound injectors back in.

T23: Switched to 36 lb-hr injectors at 50 psi.

	T21	T21	T22	T22	T23	T23
RPM	TQ	HP	TQ	HP	TQ	HP
2600	352	174	364	180	355	176
2800	350	187	362	193	352	188
3000	357	204	369	211	361	206
3200	379	231	383	233	380	231
3400	389	252	387	251	383	248
3600	385	264	385	264	382	262
3800	385	278	381	276	278	274
4000	384	292	379	289	380	290
4200	387	309	388	310	390	312
4400	406	340	408	342	396	332
4600	424	372	421	369	415	363
4800	428	392	427	391	424	387
5000	429	408	426	405	423	402
5200	430*	426	426	422	419	415
5400	421	433	431*	444	420	432
5600	424	452	423	451	426	455
5800	420	464	420	464	426	470
6000	413	471	420	480*	420	480
Max	430	474	431	480	427	483
Avg	397	330	400	332	396	329

MEETING DEADLINES
A month went by after the EFI tests and we were a little pressed for time before the next test was due. In a rush to meet the deadline, we hooked DM back onto Westech's dyno and started swapping rocker arms to see if there would be any extra power there. However, the first thing we were greeted with was a loss almost 30 hp and 20 ft-lb of torque (compare T22 and T24)! We still have no idea how or why this happened, but it only got worse from there.

T24: TFS aluminum heads, Edelbrock Victor EFI manifold (PN 29785), F.A.S.T. EFI system with Accufab throttle body and 30 lb-hr injectors at 50 psi COMP Cams Xtreme Energy EFI prototype hydraulic roller camshaft (281/288 advance duration, 230/236 duration at .050, .544/.555 lift with 1.6 rockers, 113 LS) straight up. COMP Cams 1.6:1 Pro Magnum roller rockers, 36 degrees total advance.

T24 was actually supposed to be just a back-up test to confirm the previous month's results just like we did at the start of every month so nothing was changed at all. Only this time the power fell off, and no one knows why. Since we were already on the dyno, we figured we'd continue with our planned day's tests and swap some rocker arms anyways.

T25: Swapped COMP Cams 1.5:1 Pro Magnum roller rockers on exhaust only.

For T25 we pulled an old-fashioned hot rodder's trick that sometimes works today. We left the intake rockers alone and swapped a lower ratio set of exhaust rockers on. That allowed DM to breath just a little more air into its cylinders and helped to make a little more power because of it.

	T24	T24	T25	T25
RPM	TQ	HP	TQ	HP
2600	347	172	352	174
2800	346	184	348	186
3000	351	200	351	200
3200	367	224	369	224
3400	370	240	370	240
3600	367	252	366	251
3800	363	262	361	261
4000	366	278	366	279
4200	372	298	374	299
4400	383	321	387	324
4600	400	350	398	349
4800	404	369	402	368
5000	400	380	399	380
5200	406	402	402	398
5400	406	417	410	422
5600	406	432	407	433
5800	405	447	402	444
6000	394	450	395	452
Max	407	451	410	453
Avg	381	315	381	316

FAST BURN DREAMS
When we first tested DM using the GM Performance Parts cast-iron Vortec cylinder heads the results were outstanding. Then we thought about running GM's Fast Burn aluminum heads, which were based on the Vortec castings, but with some radical changes. For one, the Fast Burn heads have a much larger 210cc intake runner, which, in hindsight, might have been just a bit too much for the little Mouse. Second, we tried a new COMP Cams Xtreme Energy hydraulic roller camshaft that also may have been too big for our needs. In the end, the Fast Burn heads worked well, but power was down when compared to the other set of aluminum heads we'd ran before, which had smaller 195cc chambers. We think this really points out the importance of properly matching components to your application. And that going too big is still not the best way to make power today.

T26: GMPP Aluminum Fast Burn heads (9.2:1 cr, 62cc chambers, 210cc runners, 2.00-inch hollow stem intake valves, 1.55-inch Sodium filled exhaust valves), GMPP single-plane intake manifold, Speed Demon 750 carb, COMP Cams Xtreme Energy hydraulic roller camshaft XR-282-HR (230/236 at .050, 282/288 adv, .510/.520 lift, 110 LS). GMPP 1.5:1 aluminum roller rockers, 36 degrees total advance.

	T26	T26
RPM	TQ	HP
2600	361	179
2800	362	193
3000	383	219
3200	393	239
3400	393	254
3600	393	270
3800	392	284
4000	393	299
4200	401	321
4400	417	349
4600	425	372
4800	428	391
5000	426	405
5200	423	418
5400	420	432
5600	415	442
5800	408	451
6000	399	455
6200	383	452
Max	428	455
Avg	402	332

LASTING IMPRESSIONS
Our last set of tests for DM included swapping out the 750-cfm carb for a Holley Street Avenger TBI system we had lying around our office. This test did not go too well and we were plagued with failure almost from the start. The engine wouldn't make anywhere near the power it had been making before (compare T26 and T27), and it turned out that our Holley parts had sat in our offices for way too long before we tested them because we learned too late that Holley had updated them since. Our EFI fuel map was wrong for the throttle body we were trying to run so we had a tuning nightmare all day long and when we finally got DM to run, it was almost too late. Since these last tests were such a bust, we've decided to rebuild DM and equip it with the newest Holley components and a smaller set of cylinder heads to make sure it'll run correctly next time out.

T27: GMPP Aluminum Fast Burn heads (9.2:1 cr, 62cc chambers, 210cc runners, 2.00-inch hollow stem intake valves, 1.55-inch Sodium filled exhaust valves), GMPP single-plane intake manifold, Holley HP750 carb with 73/84 jets, COMP Cams Xtreme Energy hydraulic roller camshaft XR-282-HR (230/236 at .050, 282/288 adv, .510/.520 lift, 110 LS). GMPP 1.5:1 aluminum roller rockers, 36 degrees total advance. T28: Installed Holley Commander 900-cfm four-bbl electronic throttle body fuel injection.

	CARB		HOLLEY TBI
	T27	T27	T28	T28
RPM	TQ	HP	TQ	HP
2600	359	178	373	185
2800	383	204	387	206
3000	398	227	397	226
3200	402	245	396	241
3400	398	257	394	254
3600	393	269	391	268
3800	394	285	386	279
4000	407	307	389	296
4200	417	334	404	323
4400	421	353	409	343
4600	417	365	409	359
4800	413	378	402	368
5000	408	389	394	375
5200	402	398	381	377
5400	396	407	367	378
5600	390	415	365	389
5800	379	418	354	391
6000	366	417	N/A	N/A
Max	421	419	409	391
Avg	397	325	388	309

REBUILD, REPAIR, AND RE-TEST
We've learned that no matter how tough you build an engine, there comes a time when it will need to rest. Now is DM's time to rest, while we rebuild it to make it stronger and faster. We've got many more tests and ideas in store, but want to really encourage you to send in your ideas. Send us you wildest fantasy engine build! Or maybe some combination your friend has been running that you can't figure out how it makes as much power as it does. Any idea you have is worth listening to. Of course, we can't run them all and even the ones we do run might be modified a bit to make work within our time and budget constraints. But the bottom line is that DM will live again and continue to be a better way for you to learn how to make the most bang for your bucks.