I have a '92 F-Bird, 305, TBI, stock (peanut) cam with 66.000 miles.
Mods I've done so far:
March steel underdrive pulley set, open element aircleaner, Dynomax 2 1/5" exhaust system.
Mods to come soon: Edelbrock T.E.S., polyurethane bushings, gas shocks 'n struts and.... see below...

I'd like to install the Comp 1.6 ratio Pro Magnum Roller Rockers.
After searching the postings exhaustivly I didn't get any hint if they will just install on my car or not.

Competition Cams

(look at their website at: http://www.compcams.com/information/.../ProMagnum.asp )

say the part# 1318-16 will install on "Chevrolet V8 1988 & later with self-aligning rockers".

O.K., I have a '92 305 TBI, so I should get them installed (center-bolt vc). AFAIK I have self-aligning stock rockers (correct me if I'm wrong), so these should fit right in. There are no footnotes behind the part# so I'm sure, that I don't need screw-in studs and guideplates(self-aligning).

In all postings I have seen so far, there was always a big "but" accompanying roller rockers of any type and their installation on any type of engine, but I could never figure out if these "buts" would apply to my kind of engine or not.

So I compiled my own couple of questions, to go for sure. Here they are:

Q#1: Does anybody have these rockers #1318-16 installed on his 305 of this year ('92,+-) and type (TBI)?

Q#2: Did they install without any hassle?

Q#3: Do they fit with the center-bolt valve covers for which, I assume, they (#1318-16) were made?

Q#4: Are there any problems using the stock push rods?

Q#5: Are there any clearance-problems with the head guideholes with these rockers in late model ('92) heads?

Q#6: Are there valve/piston clearance problems with the stock (peanut) cam when using these rockers (Though I assume there are no problems due to the mini-lift the stock cam provides, but just to be sure)?

Q#7: It is said, that one should use 10-12% stronger-than-stock valve springs when running higher-lift rockers. Can anybody confirm this? Or, more precisly, can I run higher-lift 1.6 ratio rockers with stock valve springs, while maintaining the stock cam, without any problems?

Q#8: I saw sysxx's postings about _not to install 1.6 ratio rockers on worn out valve springs. Though this makes sense to me, the question is "When are valve springs worn out"?
As I said above, my car has 66.000 miles on the odo and is in very good condition. Is this too much for the springs, or are they still good enough?

Thank you in advance,

Andreas

 

I have a 91 Z28 and had these roller rockers on my car. I'm sure these will fit on your car! My car has the center bolt valve covers and uses self-aligning (rail style) rockers. I have a set of the 1.6 roller rockers you are looking for, the Crane Magnum 1.6 roller rockers part number 1418-16. I could not use them on my new engine because the springs on my AFR heads were rated for lifts up to .540. If I were to use the 1.6 ratio rr's I would have exceeded my max lift, so i put the 1.5's on my new motor. Anyway, I have a set of these roller rockers you want. I had them on my car from April of last year until November (aprox 6mo) and 2500 miles on them. they are brand new, and they are the rail style which is the self-aligning type. I want 125$ for them. I paid 200$ at summit for them. Send me a private msg or email me.

Craiger

I have the Magnum's....not the Pro magnum's....Pretty much the same thing, but you may want to go to their web site to look at the difference. I would send you a pic, however, I do not have a scanner and my digital camera is broke

 

He wants and is talking about Comps FULL roller rockers 1318-16, not just the roller-tipped "roller rockers", 1418-16 (terrible name!). BIG difference. For 70 bucks more you get full roller rockers!

I bought some and, sorry to say, there was NO way they would fit under my ZZ4 or HO330 valve covers. Hit the horizontal web supports between the rockers. Went to perimeter bolt valve covers. ETec-200 heads can use either, phew.

 

@ fast_broker:

thanks for your reply. I think I stay with the roller tip ones.

A.