2.55 Pulley Getting KR *Update* - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


Performance, Brainstorming & Tuning Talk about modifications, or anything else associated with performance enhancements. Have a new idea for performance/reliability? Post it here. No idea is stupid! (please use Detailing and Appearance for cosmetic ideas)

Reply
 
 
 
Thread Tools Search this Thread
Old 08-27-2007, 09:17 PM   #1
Senior Member
True Car Nut
Thread Starter
 
Join Date: Jan 2006
Location: NEBF:06,07 | NYBF:06,07 | ONBF:06,07 | CNBF:06 & more............
Posts: 8,029
Thanks: 0
Thanked 0 Times in 0 Posts
bandit is on a distinguished road
Default 2.55 Pulley Getting KR *Update*

So i put the 2.55 pulley on down at boostys this weekend.

First off i did scan before the pulley, everything looked fine, no KR at all.

It was feeling good but i could feel something at like 70%+ throttle so i did not get on it much.
Today i scanned for KR, O2, and Tested the Fuel pressure while driving.
Out side Temp 75-80*F



In First gear i get about 1-2 KR at 70+% throttle.
in Second gear i get 3-4 KR at 70+% ( More KR the higher throttle, Saw 6 once)
in third gear i saw 2-3 KR sometimes.

Fuel pressure at like 10% throttle was like 38ish, Idol about 35-36. When i nailed it it jumped right up to 46-48 and stayed there even when i started to get KR.


Now for the O2.

First gear at 70%+ throttle i was seeing 885-895 (once i saw 910 when i frst started driving)
Second Gear at 70%+ throttle i saw 860-875. Mostly 870-875 and it did not Drop when the KR started.


So the question is, I know my fuel pressure at the fuel like is good, But how are my O2 Readings?
Normal? Low? Right on?



Things i have done....
-TR55 Plugs gaped to 60
-K&N Filter on Rice pipe
-2.55 pulley


Other things old or need to be done...
-wires are newish looking and in good shape but are cheap ones.
-PCV has not been done yet
-Fuel filter, but fuel pressure is fine.
-SCer Coupler, Have it waiting to go in.
-Belts, starting to crack.
bandit is offline   Reply With Quote
Old 08-27-2007, 09:22 PM   #2
Junior Member
 
Join Date: Apr 2006
Location: Purgatory
Posts: 0
Thanks: 0
Thanked 0 Times in 0 Posts
Bonneville92V688 is on a distinguished road
Default

If I'm not mistaken, I had to gap my Autolite 104s to .055 when I dropped a pulley size. That was on my '94.
Bonneville92V688 is offline   Reply With Quote
Old 08-27-2007, 09:25 PM   #3
Senior Member
True Car Nut
 
Join Date: Jul 2004
Location: Twin Falls, Idaho
Posts: 7,545
Thanks: 0
Thanked 1 Time in 1 Post
Hans is on a distinguished road
Default

so you're running one heat range colder plugs at 0.60, I'd reccomend 0.55

0.52 for 2 heat range colder, just what I've found works best in my experience.

Are you saying you checked the fuel pressure under load (remote line) ?\

My fuel pressure was fine at idle but was dying at the top end. a new fuel pump fixed nearly all of my KR issues.
Hans is offline   Reply With Quote
Old 08-27-2007, 09:33 PM   #4
Junior Member
Posts like a Ricer Type-R
 
Join Date: Aug 2002
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
willwren is on a distinguished road
Default

Re-gap your plugs.

Wires won't generally cause KR like that. 1-2 degrees is acceptable on pump gas in those temps, and tells you that you've pushed as far as you can.

How old is the O2?

I suggest completing the standard tune-up items and regapping your plugs for starters. After that, we'll be chasing small vacuum leaks and exhaust leaks. It wouldn't hurt to clean your TB and MAF sensor if that hasn't been done yet, and replacing your PCV valve.
willwren is offline   Reply With Quote
Old 08-27-2007, 09:43 PM   #5
Senior Member
True Car Nut
Thread Starter
 
Join Date: Jan 2006
Location: NEBF:06,07 | NYBF:06,07 | ONBF:06,07 | CNBF:06 & more............
Posts: 8,029
Thanks: 0
Thanked 0 Times in 0 Posts
bandit is on a distinguished road
Default

Thanks guys, You make me feel better now

O2 looks to be factory, i was planning on replacing it soon anyway just cuz its old.

im going to re-gap those tonight if i get the time.


Hans- Yup i ran a high pressure line thats like 7 feet long. Works great for testing while driving never leaks
bandit is offline   Reply With Quote
Old 08-28-2007, 04:08 PM   #6
Senior Member
True Car Nut
Thread Starter
 
Join Date: Jan 2006
Location: NEBF:06,07 | NYBF:06,07 | ONBF:06,07 | CNBF:06 & more............
Posts: 8,029
Thanks: 0
Thanked 0 Times in 0 Posts
bandit is on a distinguished road
Default




Yup, Re Gapping the plugs made all the difference

It was 87*F out side and i waited for the engine temp to hit 180* and then started the testing.

First gear. No KR. saw Maybe a 1 once and thats it.
Second Gear at like 90%+ throttle i saw 1-2 and 3 once. But like wren says with no race fuel and a Hot day like today thats ok.
I just wont keep it floored for long at floored all the way when i know its this hot out.

Tonight im going to do more testing, it should get down to the mid 60'* so that should be fun
bandit is offline   Reply With Quote
Old 08-28-2007, 04:16 PM   #7
DINOSAURUS BOOSTUS

Expert Gearhead
 
BillBoost37's Avatar
 
Join Date: Mar 2005
Location: Enfield, CT
Posts: 41,391
Thanks: 0
Thanked 0 Times in 0 Posts
BillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of light
Default

IMO 1-2 degrees is still knock. All knock is bad, if you don't tune your car to run 100% in the worst weather then you are tuning your car for fair weather only.
BillBoost37 is offline   Reply With Quote
Old 08-28-2007, 04:20 PM   #8
Senior Member
True Car Nut
Thread Starter
 
Join Date: Jan 2006
Location: NEBF:06,07 | NYBF:06,07 | ONBF:06,07 | CNBF:06 & more............
Posts: 8,029
Thanks: 0
Thanked 0 Times in 0 Posts
bandit is on a distinguished road
Default

Quote:
Originally Posted by BillBoost37
IMO 1-2 degrees is still knock. All knock is bad, if you don't tune your car to run 100% in the worst weather then you are tuning your car for fair weather only.
not to argue with you bill but...

Quote:
Originally Posted by willwren
Wires won't generally cause KR like that. 1-2 degrees is acceptable on pump gas in those temps, and tells you that you've pushed as far as you can.
Who'* right here?

i'll let you two figure that out and then i will start to look.

I dont want to replace $200 in parts and take off the Manifolds to check for cracks and do all sorts of other things to just find that im still getting 1-2 KR
bandit is offline   Reply With Quote
Old 08-28-2007, 05:07 PM   #9
Junior Member
Posts like a Ricer Type-R
 
Join Date: Aug 2002
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
willwren is on a distinguished road
Default

1-2 is the acceptable 'rule of thumb' when pushing performance. You know you've pushed as far as you can.

If you get zero all the time, how do you know what you COULD have done? Think about it.

My personal target is 1-2 in 90+ degree temps, heatsoaked, and at WOT.
willwren is offline   Reply With Quote
Old 08-28-2007, 06:09 PM   #10
Senior Member
True Car Nut
Thread Starter
 
Join Date: Jan 2006
Location: NEBF:06,07 | NYBF:06,07 | ONBF:06,07 | CNBF:06 & more............
Posts: 8,029
Thanks: 0
Thanked 0 Times in 0 Posts
bandit is on a distinguished road
Default

Do you think if it went down to like 50 or 52 Gap, would that help or hurt anything?
bandit is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
2.2" pulley, getting bad belt slip at 4800rpm... TrueWildMan Forced Induction 50 07-14-2004 06:27 PM
Getting close to getting a chip... TrueWildMan Performance, Brainstorming & Tuning 20 06-15-2004 10:28 AM
getting smaller pulley what belt would i need jachin Forced Induction 7 11-04-2003 11:29 PM
How much boost are you getting with 3.4" pulley?? 2000SilverBullet Forced Induction 13 05-20-2003 07:59 AM
Getting new job.. getting paid, getting mods Wolfedog50 Performance, Brainstorming & Tuning 3 05-08-2003 02:31 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 12:27 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.