The Insane Inline, Part 3

Power Play
For our chassis dyno numbers we revisited The Dyno Shop in Santee, California. Owner Mark MacNeil and the rest of the gang have forgotten more about diagnosing, modifying, measuring, and extracting power from vehicles ranging from $100K turbo Porsches to carbureted dune buggies than we'll ever know. The Dyno Shop baselined our XJ back when it was stock and when we added our Gibson header and exhaust, K&N FIPK air intake, Performance Distributors Firepower Ignition Kit, Rubicon Express 62mm throttle body, and Hypertech Power Programmer (although the stroker uses factory computer calibrations).

MacNeil says our horsepower levels could be brought up quite a bit more with some computer tweaking and some leaning of the air/fuel curve. We were nervous about dinging our new engine, so we purposefully jetted our NOS nitrous system too rich. We're considering adding a larger 66mm throttle body down the road to get some more air into the engine and may tweak the computer, but for now we're happy with the added power across the entire rpm range without worrying about knocking or harming the engine.

Even though we've been experimenting with 89- and 87-octane fuel, all of our dyno testing was performed with 91-octane premium pump gas.

Test 1:
Bone Stock 4.0L

RPM:	Power:	Torque:	Air/Fuel Ratio:
3,500	114	171	11.9:1
3,600	116	170	11.9:1
3,700	118	168	11.8:1
3,800	124	172	11.7:1
3,900	130	176	11.7:1
4,000	127	166	11.8:1
4,100	125	161	11.8:1
4,200	126	157	11.7:1
4,300	128	156	11.7:1
4,400	129	154	11.6:1
4,500	131	153	11.4:1
4,600	132	151	11.4:1
4,700	133	148	11.5:1
4,800	133	145	11.4:1
4,900	130	139	11.3:1
5,000	130	137	11.2:1
5,100	126	130	11.1:1
5,200	124	125	10.9:1
5,300	122	121	10.8:1
5,400	NA	NA	NA

Test 2:
4.0L Gibson Header and after-cat exhaust, Rubicon Express 62mm throttle body, K&N FIPK air intake, Hypertech Power Programmer, Performance Distributors Firepower Ignition Kit

RPM:	Power:	Torque:	Air/Fuel Ratio:
3,500	132	197	14:1
3,600	134	195	13.7:1
3,700	136	193	13.7:1
3,800	142	196	13.9:1
3,900	146	197	14.1:1
4,000	152	200	14.2:1
4,100	147	188	14.3:1
4,200	149	187	14.3:1
4,300	150	183	14.3:1
4,400	151	180	14.2:1
4,500	152	178	14.0:1
4,600	152	174	13.9:1
4,700	152	169	13.8:1
4,800	151	165	13.8:1
4,900	146	157	13.7:1
5,000	142	150	13.7:1
5,100	139	143	13.6:1
5,200	138	140	13.5:1
5,300	NA	NA	NA
5,400	NA	NA	NA

Test 3:
Golen Engine Supply 4.6L with Turbo City mods & Accel Injectors

RPM:	Power:	Torque:	Air/Fuel Ratio:
3,500	149	224	11.9:1
3,600	152	222	12.0:1
3,700	154	218	12.1:1
3,800	155	215	12.1:1
3,900	162	218	12.1:1
4,000	165	217	12.0:1
4,100	167	213	11.9:1
4,200	172	216	11.8:1
4,300	167	204	11.8:1
4,400	164	196	11.7:1
4,500	161	188	11.6:1
4,600	162	185	11.5:1
4,700	163	182	11.5:1
4,800	164	179	11.5:1
4,900	161	172	11.6:1
5,000	161	169	11.6:1
5,100	158	162	11.6:1
5,200	147	149	11.5:1
5,300	123	121	11.3:1

Test 4:
Same as Test 3, but with NOS 75hp Nitrous System

RPM:	Power:	Torque:	Air/Fuel Ratio:
3,500	NA	NA	NA
3,600	182	268	10.9:1
3,700	177	251	10.6:1
3,800	177	244	10.1:1
3,900	173	233	10.0:1
4,000	187	245	10.0:1
4,100	203	260	10.0:1
4,200	204	256	10.0:1
4,300	204	249	10.2:1
4,400	207	247	10.1:1
4,500	211	247	10.1:1
4,600	209	239	10.0:1
4,700	208	233	10.0:1
4,800	210	230	10.0:1
4,900	211	226	10.1:1
5,000	207	217	10.2:1
5,100	203	209	10.0:1
5,200	191	193	10.0:1
5,300	NA	NA	NA

Clearing the Smog Hurdle
There's been a lot of speculation as to whether or not a stoker engine with a hotter Comp Cam's Xtreme 4x4 268 cam would pass the sniffer test. With Turbo City's tuning completed, we swung by our local smog station and had the 1999 XJ tested. Our XJ not only passed, but passed with flying colors. The HC level was half of the maximum allowable, the CO level was merely 10 percent of the allowable level, and the NO was 34 percent of the allowable level. We're all legal and in compliance. As far as the state is concerned, it's just another replacement engine that blows clean through the tailpipe.

The Insane Inline, Part 1
The Insane Inline, Part 2
The Insane Inline, Part 3