C4 dyno questions
05-03-2003, 08:56 PM
#1
Pro
Thread Starter
Join Date: Jan 2002
Location: Michigan
Posts: 531
Likes: 0
Received 0 Likes
on
0 Posts
C4 dyno questions
Having the 89 C4 put on a dyno in about a week. It's a 4-wheel drive dyno so I should be OK, right? Or should I disconnect the front coupler and dyno from the rear wheels only. Anyone BTDT?
I'm getting some pre-MAF installation numbers.
Drew
89 C4
86 930
I'm getting some pre-MAF installation numbers.
Drew
89 C4
86 930
05-03-2003, 11:30 PM
#2
Addict
Rennlist Member
Rennlist Member
Just got back from Dyno Day with the PCA-Riesentoter chapter at AWE Tuning in Willow Grove, PA. They featured a 4-wheel Dyno made by Mustang. The main point of this particular Dyno is the electromagnetic coupler between the rear and front rollers. This assures an exact speed match on the 4 wheels. They explained that other types of machines utilize computer controlled motors to sync the front and rear rollers, and as such, could mis-match the roller RPM. Apparently, this is BAD as the Porsche coupling doesn't like differing speeds between front and rear.
We ran 12 cars through their paces, with half being C4's(964C4, 993C4,996C4s and 2@996TT)
Results were impressive showing some real horses being put to the wheels:
My own 90-964C2 Tip = 207.5 HP
94-964C4 (chipped, intake and exhaust mods)= 217HP
79-930Turbo = 236.5 HP
69-911 (with 3.0L engine set for tracking) = 226HP
71-911 2.5L stock = 145.6 HP
97-993C4 = 201.6 HP
996C4 = 238 HP
02-996TT = 347.4 HP
02-996TT (European exhaust mods)= 370 HP
They figure 28% drivetrain loss for a C4, 18% loss for a C2, but are unsure of the drivetrain losses through the Tip, but we settled on 20%. That put the 996TT (modified) at 474 Engine Horsepower!
We ran 12 cars through their paces, with half being C4's(964C4, 993C4,996C4s and 2@996TT)
Results were impressive showing some real horses being put to the wheels:
My own 90-964C2 Tip = 207.5 HP
94-964C4 (chipped, intake and exhaust mods)= 217HP
79-930Turbo = 236.5 HP
69-911 (with 3.0L engine set for tracking) = 226HP
71-911 2.5L stock = 145.6 HP
97-993C4 = 201.6 HP
996C4 = 238 HP
02-996TT = 347.4 HP
02-996TT (European exhaust mods)= 370 HP
They figure 28% drivetrain loss for a C4, 18% loss for a C2, but are unsure of the drivetrain losses through the Tip, but we settled on 20%. That put the 996TT (modified) at 474 Engine Horsepower!
05-04-2003, 12:16 AM
#3
Pro
Thread Starter
Join Date: Jan 2002
Location: Michigan
Posts: 531
Likes: 0
Received 0 Likes
on
0 Posts
OK, I'll call Monday and find out what kind of dyno they have, and how it goes about matching the front and rear wheel speeds. If it's only computer controlled like you stated and there could be a difference in speeds do you think I should just disconnect the fronts? Thanks for the input...
Drew
89 C4
86 930
Drew
89 C4
86 930
05-06-2003, 10:12 AM
#4
Addict
Rennlist Member
Rennlist Member
I'm certainly not a dyno expert, having had it done for the first time on Saturday. The explaination was from the tuner that stated that he researched the different types and decided on this type (so we need to temper his response)
