ZZP 2.7 Pulley Series I
 

I have decided to go wtih a 2.7 pulley to play it safe.

-I have an intake which keeps intake temps around 6-7* above ambient.
-1 step colder plugs (91-940) and Napa (Beldin) Wires
-180 Thermostat
-I live at 5,200 ft.

When scanning with my actron I still get 2-3* KR at WOT. If I go wtih a 2.55" pulley then I will most likely have even more KR. Exaust mani work, a high flow cat, an updated fuel pump, and possibly new injectors are what I am thinking of doing. What is reccomended?

Until you solve the KR, I would suggest holding off on the smaller pulley. Each degree of KR takes away more power than you wish to give up.

Willwren asked my why I went with such a small drop in pulley size. With 2.85" pulley I had no knock. WIth a 2.7" I have 3-4*. Just think if I had taken his advice and went wtih a 2.55" off of a 92-93....Will the 1.8 rockers help me out without doing additional mods?

I know that the high possibility of cracked exhaust manis will increase KR, but will the rockers at least help? Thanks for the opinions...

If your manifolds are cracked, fix and port them. That much KR on a 2.7 is BAD. Especially this time of year in the cool weather.

If your manifolds were cracked, you shouldn't have swapped pulleys.

Rockers on stock exhaust manifolds would be like trying to blow up a balloon inside a bottle. You're not going to get much out of the rockers until you port your exhaust manifolds.

That 2-3° of KR is going to be NASTY come summer. Get that fixed or go back to the stock pulley. You are running 91 octane fuel or higher, correct?

That is 105* in denver in the summer KR, not March 14, 2007 KR. I have none right now in the 75* range outside...

Always 91 premium...

You are at your limit then. But if your manifolds are cracked, it's costing you, and it's going to get worse.

I do get 20 mpg in town and upto 33 hwy. Will ported / repaired manis benifit that as well?

Your fuel mileage has no bearing on this whatsoever. It's about exhaust velocity.

I saw your post on porting and painting your manifolds and crossover. How did the paint hold up? how are the manifolds now versus when you did the job? (how long has it been and how many miles have you put on them)


Sorry for my lack of detailed knowlege of the BonnevilleClub Forum. As I stated in earlier posts, I am a ClubGP guy and they know very little about series I motors and ideas. Some of the easy to buy parts (headers, ported exhaust, rockers, intakes, pulleys, intercoolers) are not as easy to come up with in older motors like the series I.

My goal is to make a safe, streetable, higher than stock performing car that is different from the average. Thanks for the input...

Paint didn't hold up for more than 3 hours, but did leave a VERY thin ceramic coating behind. Forget paint. You need to use a ceramic coating like I did later. I'll leave it to you to find that topic. I'm on the way out the door right now.