1.6 RR questions

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Jul 31, 2006 | 01:23 AM

89Corvette6spdFX3

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1.6 RR questions

In my process of upgrading my engine, my next step after headers is having some RR put in. I have a couple questions about this mod before I invest in it.

1st- will 1.6 RR fit under my stock 89 L98 valve covers?
2nd- will I need to (or should I) replace anything else when doing this upgrade?
3rd- are the GM RR's a good choice or is there anything better?

Thanks for the help.

Jul 31, 2006 | 01:35 AM

vader86

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From: Athens AL

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You will probably need to dremel out the inside of the valve cover for clearance. You dont have to replace anything else, and I would go with Comp Cams rockers.

Jul 31, 2006 | 01:39 AM

Irishpilot03

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From: Sumter South Carolina

1.6 RRs are a good upgrade to do, but there are some things to be aware of. Depending on the amount of mileage and the way you drive the car, you will probably need to upgrade the springs and put in some chromoly pushrods to handle the extra strain/lift from the RRs. If you don't change the rods and springs when you do this, they will wear out and/or fail later, so you might as well do it all. You don't have to replace these components, but it is good insurance especially if you race. Your stock valve covers should fit the extra lift from the RRs, but if you have an aftermarket cam, you probably will need taller covers. When I upgraded my LT1, I had to modify the stock covers to fit the wider RRs. They were scraping on the drip tabs, but I've heard that L98s don't have that problem. I'm sure some of the L98 guys will chime in. GM RRs are a good choice, but I decided to go with Pro Magnum 1.6 RRs because they were a good price and they are reputable.

Jul 31, 2006 | 09:49 AM

89Corvette6spdFX3

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I'm planning on eventually having my 113 heads ported and polished. I really don't drive the car very much but just around town and sometimes to the local vette meet.

Think I could get away with having them put on now without the springs/pushrods? As for racing, I rarely go to the strip with it, but I do get on it occasionally like getting onto the highway.

So I need to compare:

GM High Performance
Comp. Cam
Pro Magnum

Any others?

Jul 31, 2006 | 09:56 AM

Irishpilot03

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From: Sumter South Carolina

If you are planning on porting/polishing your heads, I would definitely throw in a more aggressive cam. With a higher lift cam, and 1.6RRs, you would be taking advantage of more hp gain. They compliment each other. I would recommend that you do some studying on good cam/heads packages, and choose the one that's right for you. They range from mild street, to straight racing. Good luck with what you choose!

Jul 31, 2006 | 10:01 AM

88BlackZ-51

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Quote:

Originally Posted by 89Corvette6spdFX3

I think summit sells the Pro Magnum's for $265. You cant go wrong!

Jul 31, 2006 | 10:08 AM

ALLT4

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From: Howard PA

At the very least, if you don't want to spend the money now, check for the max lift your stock springs and seals can take.

Buy a checking valve spring and try to get it installed, if you don't know how to do this find someone who does or ask in another thread here. Open the valve until you reach your stock spring coil bind number. See if the retainer is hitting the seal, if it's not you're probably OK.

Or figure out how much your total lift will be, open the valve to that number and see how things look.

You don't want coil bind.
You don't want the retainer to hit the seal.
It would be nice to see a safety margin of .060 on the spring at max lift.

Installed height minus coil bind = total gross lift

Gross total lift minus Actual lift = safety margin.

The Hot Cam and Hot Cam springs on an LT1 winds up being .040 so that may even be safe as a lot of guys just run it that way.

Jul 31, 2006 | 11:33 AM

madmatt9471

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From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----

You'll need to remove the oil drip tabs on the top of the valve covers DO NOT SNAP OFF you must grind them down with a dremal or similar tool, you'll crack the valve cover. But with all said they will fit. I put a set of self aligning Crane Gold 1.6 RR's on my '90 and it loved it albeit I installed a set of chromed aluminum covers from GM so I did not have to worry about the tabs and they just fit perfect!

Thanks,Matt