L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
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From: Cincinatti OH
Car: 1991 L03 700r4 RS
Engine: 1987 WS6 Trans AM Lb2
Transmission: Th350 red neck Performance 3k stall
Axle/Gears: 95 Mustang 8.8 built with 3.73s
L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
I just purchased a 1996 LT1 camshaft for my L98 to get rid of the grooves in the cam I got last year when some vavle springs broke. I know if I run my 1.6 RR's on this cam I'm going to have close to .490 lift, can I get away with this if I use shorter vavle seals or is it possible it will clear the way the car sits? I already have .550 lift springs installed I just want to make sure I don't have to down grade to the old 1.5 stamped rockers to run this cam. Any help is greatly appreciated. Thanks in advance.
Joined: Sep 2003
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
i dont think it will clear. think the retainers will hit the guides at .480 lift depending on the retainer design.
Just get a set of .050" of shims and .050" offset locks. this will raise the spring assembly and give you .530" of clearance.
BUT before you do that, i'd advise you check your clearances to see how much lift you have between the retainer bottom and the guide boss/seal.
Just get a set of .050" of shims and .050" offset locks. this will raise the spring assembly and give you .530" of clearance.
BUT before you do that, i'd advise you check your clearances to see how much lift you have between the retainer bottom and the guide boss/seal.
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From: Cincinatti OH
Car: 1991 L03 700r4 RS
Engine: 1987 WS6 Trans AM Lb2
Transmission: Th350 red neck Performance 3k stall
Axle/Gears: 95 Mustang 8.8 built with 3.73s
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
That's my plan as of now, someone had already done away with the umbrella seals on the exhaust side and I really DONT want to invest in new retainers, I'de rather dremel the ones I have
Hopefully this goes as planned I don't want to have to mess around anymore. I guess I could just stick the Lingenfelter cam I have in the block with the 1.5 stamped rockers but that'll suck.
Joined: Sep 2003
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
you wont need new retainers with the offset locks. locks aint that expensive and shims are like 20 bucks, so its a safe easy cheap way of doing things
Thread Starter
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From: Cincinatti OH
Car: 1991 L03 700r4 RS
Engine: 1987 WS6 Trans AM Lb2
Transmission: Th350 red neck Performance 3k stall
Axle/Gears: 95 Mustang 8.8 built with 3.73s
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
Where do I acquire these?
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From: Cincinatti OH
Car: 1991 L03 700r4 RS
Engine: 1987 WS6 Trans AM Lb2
Transmission: Th350 red neck Performance 3k stall
Axle/Gears: 95 Mustang 8.8 built with 3.73s
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
Yeah this is annoying, I can only find the locks for .050 offset in 10 degree and that sucks, I just want some basic stock cheapo's and some shims to get these things setup without destruction.
Joined: Sep 2003
Posts: 25,895
Likes: 429
From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
try summit racing or jegs. i do believe there are 7 degree .050" offset locks. i think manley has some
Only other thing is possibly shaving down the retainers you have. you only have to take off about .020" which isnt much.
Only other thing is possibly shaving down the retainers you have. you only have to take off about .020" which isnt much.
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From: Carson, CA
Car: '88 GTA, 90 Formula
Engine: 5.7 TPI, fed growth hormones
Transmission: 700r4 4u2?
Axle/Gears: 9bolt
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
BEWARE!
On my stock '88 GTA 350, stock cam and heads, I installed 1.6 Roller rockers, and had a lot of noise and bent pushrods. When I pulled the heads off, you could see where the intake valves had been hitting the pistons on ALL the cylinders. I didn't change the timing set before the rocker install, so I'm not sure where the cam timing was, but it was the STOCK CAM! Needless to say, I was VERY surprised to see that.
Beware!!
TA
On my stock '88 GTA 350, stock cam and heads, I installed 1.6 Roller rockers, and had a lot of noise and bent pushrods. When I pulled the heads off, you could see where the intake valves had been hitting the pistons on ALL the cylinders. I didn't change the timing set before the rocker install, so I'm not sure where the cam timing was, but it was the STOCK CAM! Needless to say, I was VERY surprised to see that.
Beware!!
TA
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From: Michigan
Car: 1987 Trans Am
Engine: 5.0L TPI
Transmission: 700R4
Axle/Gears: Richmond 3.73
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
ouch....that has to suck.
Makes me think twice about buying a set of 1.6's for my car.
Makes me think twice about buying a set of 1.6's for my car.
Joined: Sep 2003
Posts: 25,895
Likes: 429
From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
my car has 158K miles on it, and a stretched timing chain. I ran 1.6 rockers for 500 miles or so before winter storage with no problems. Many others have done the same, you should NOT be hitting valves with stock cam. Timing must have been way off ideal intake centerline.
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From: Michigan
Car: 1987 Trans Am
Engine: 5.0L TPI
Transmission: 700R4
Axle/Gears: Richmond 3.73
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
yeah i have a new timing set on my car. I swapped it when I swapped the cam.
Joined: Sep 2003
Posts: 25,895
Likes: 429
From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
a point to make about 1.6 rockers over 1.5's is they only will help if the heads will flow more air with the extra lift. If your heads outflow the intake manifold, then you probly wont gain too much more either with more lift.
So if you can gain more with an extra .030" of lift or so, then shoot for it
So if you can gain more with an extra .030" of lift or so, then shoot for it
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From: Cincinatti OH
Car: 1991 L03 700r4 RS
Engine: 1987 WS6 Trans AM Lb2
Transmission: Th350 red neck Performance 3k stall
Axle/Gears: 95 Mustang 8.8 built with 3.73s
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
I already have 1.6 roller rockers as well. I wouldn't mind stepping down to 1.5's but who wants to spend money
I honestly plan to shave the stock locks, call me crazy but that's the plan right now. I can find -.050 locks all day but they move the wrong direction, I need + .050 locks and the only ones I can find are titanium and 50 bucks a set. I have a new engine, this is this one's last year so I don't care I'm going to make it work junkyard style!
I honestly plan to shave the stock locks, call me crazy but that's the plan right now. I can find -.050 locks all day but they move the wrong direction, I need + .050 locks and the only ones I can find are titanium and 50 bucks a set. I have a new engine, this is this one's last year so I don't care I'm going to make it work junkyard style! Thread Starter
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From: Cincinatti OH
Car: 1991 L03 700r4 RS
Engine: 1987 WS6 Trans AM Lb2
Transmission: Th350 red neck Performance 3k stall
Axle/Gears: 95 Mustang 8.8 built with 3.73s
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
OK this is so freaking confusing, are the seals going to get hit at .480 lift, or are the metal guides actually going to hit the locks? If it's the seals I plan to do just what I was going to do with my Vortec heads and use the Chrysler 2.2 seals. This lets the Vortecs clear over .500 lift. I guess I'm going to have to get in there and measure unless someone can put this one to rest for me.
Joined: Sep 2003
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
well the seal sits on top of the guide, so clearance depends on how wide the retainer inside diameter is. I would think max clearance point will be when the retainer hits the seal.
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
I had a LT4 Std cam with 1.6 rockers (.475" lift?) and didnt run into issues.
I also had a set of LT4 retainers and CC 981 springs.
What my brother orr was discussing, is you need a set of 0.050" retainers to move the retainer up. Then you take a spring shim around 0.050" and place it under the shim. That should move everything up 0.050 and give you a little more room for error. I believe Crower and Comp both make those retainers. But you have to call because theyre special.
I also had a set of LT4 retainers and CC 981 springs.
What my brother orr was discussing, is you need a set of 0.050" retainers to move the retainer up. Then you take a spring shim around 0.050" and place it under the shim. That should move everything up 0.050 and give you a little more room for error. I believe Crower and Comp both make those retainers. But you have to call because theyre special.
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From: Cincinatti OH
Car: 1991 L03 700r4 RS
Engine: 1987 WS6 Trans AM Lb2
Transmission: Th350 red neck Performance 3k stall
Axle/Gears: 95 Mustang 8.8 built with 3.73s
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
They're also expensive, I'de rather just grind down the locks and hope everything works out ok
If you got that LT4 cam to clear though I should definetly have the room to make it work, it'll just be getting it there. I already only have the umbrella style seals on the intake side and just the o rings on the exhaust; hopefuly we'll set it up, spin it over, and be good to go. If worse comes to worse I have a pretty hot Lingenfelter camshaft that I'll stick in there with the old 1.5 stamped rockers, it's got a little better LSA and a little more duration with a bit less lift. What seals did you use on that LT4 cam by chance?
If you got that LT4 cam to clear though I should definetly have the room to make it work, it'll just be getting it there. I already only have the umbrella style seals on the intake side and just the o rings on the exhaust; hopefuly we'll set it up, spin it over, and be good to go. If worse comes to worse I have a pretty hot Lingenfelter camshaft that I'll stick in there with the old 1.5 stamped rockers, it's got a little better LSA and a little more duration with a bit less lift. What seals did you use on that LT4 cam by chance? Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
They're also expensive, I'de rather just grind down the locks and hope everything works out ok
If you got that LT4 cam to clear though I should definetly have the room to make it work, it'll just be getting it there. I already only have the umbrella style seals on the intake side and just the o rings on the exhaust; hopefuly we'll set it up, spin it over, and be good to go. If worse comes to worse I have a pretty hot Lingenfelter camshaft that I'll stick in there with the old 1.5 stamped rockers, it's got a little better LSA and a little more duration with a bit less lift. What seals did you use on that LT4 cam by chance?
If you got that LT4 cam to clear though I should definetly have the room to make it work, it'll just be getting it there. I already only have the umbrella style seals on the intake side and just the o rings on the exhaust; hopefuly we'll set it up, spin it over, and be good to go. If worse comes to worse I have a pretty hot Lingenfelter camshaft that I'll stick in there with the old 1.5 stamped rockers, it's got a little better LSA and a little more duration with a bit less lift. What seals did you use on that LT4 cam by chance? Thread Starter
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From: Cincinatti OH
Car: 1991 L03 700r4 RS
Engine: 1987 WS6 Trans AM Lb2
Transmission: Th350 red neck Performance 3k stall
Axle/Gears: 95 Mustang 8.8 built with 3.73s
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
The camshaft is on its way but I was honestly considering buying the offset locks and spacers so I could reuse them on a set of heads later; however I've heard that spring spacers aren't good on your heads and will cause premature valve guide wear. The theory behind it seems pretty sound but have you guys ever encountered something like this? If the camshaft gets here and I recover well enough before I make up my mind on getting the offset locks or not I'll probably just stab it in and report back with the results but otherwise I may still go offset. Finally I do need to get positive offset locks correct? Like +.050 not -.050?
Joined: Sep 2003
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
it would be +.050 to raise it
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From: SOUTHERN ALBERTA
Car: 1987 IROC-Z
Engine: 310 lb9
Transmission: SEMI STOCK 700R4
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Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
I'm running a 1994 lt1 cam (.450-.460)lift with 1.6 CC magnum rockers with those it's about (.480-.490) lift and i havn't had any issues yet my engine guy said i was ok to .500" lift i'm also using LT1 springs and retianers. Not sure how you would have valve contact with the pistons unles you had 13.00:1 compression and running .600" lift must have been a bad timing set.
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From: illinois, home of liberals, D'oh!
Car: 89 Formula L98 power
Engine: '96 subaru, opposed 4banger
Transmission: TH700R4, subaru 4WD
Axle/Gears: 3.27, just works
Re: L98 stock heads, LT1 cam, 1.6 roller rockers, anything I need to beware of?
Ok yeah, I'm running my stock cam, advanced 4* with 1.6 comp cam pro magnum's, a cloyes true roller 9 keyway chain, and sportsman II heads, and my motor runs great, and has made no destruction to the valves, or pushrods. Did you take the valve covers off with the roller rockers off the valve studs? You have to make sure you torque the valve locks well enough, not to come loose, that will cause some trouble.
I have been trying to find out something. I have aftermarket taller valve covers on the motor now, that look great, see the photo's on my site:
www.cardomain.com/ride/471099
Check out the video's too, it sounds great and should be conservatively around 354hp with the mods I've done to it.
But I'm thinking about putting the stock valve covers on it for the winter, because my new ones, got a little dirty over the winter, sitting under the hood, and the cars under a cover, its no winter car. So I want them to stay nice and shiny. I'm going to take them off and clear coat them, but I may see about using the stock covers for the winter.
But I remember that TPIS uses mostly stock valvetrain stuff, and stock valve covers with no problems and I believe with roller rockers, but I think theres not enough clearance for them under the stock covers without removing the webbing. So my question is this. Have any of you, chopped out most of the metal under the covers, to utilize them? OR did you have to remove the webbing inside them and use valve cover spacers? Because the spacers are usually $110 so I may just say the hell with it. I'm still finishing up stuff with the motor, so its not all finished in a lot of the photo's
I have been trying to find out something. I have aftermarket taller valve covers on the motor now, that look great, see the photo's on my site:
www.cardomain.com/ride/471099
Check out the video's too, it sounds great and should be conservatively around 354hp with the mods I've done to it.
But I'm thinking about putting the stock valve covers on it for the winter, because my new ones, got a little dirty over the winter, sitting under the hood, and the cars under a cover, its no winter car. So I want them to stay nice and shiny. I'm going to take them off and clear coat them, but I may see about using the stock covers for the winter.
But I remember that TPIS uses mostly stock valvetrain stuff, and stock valve covers with no problems and I believe with roller rockers, but I think theres not enough clearance for them under the stock covers without removing the webbing. So my question is this. Have any of you, chopped out most of the metal under the covers, to utilize them? OR did you have to remove the webbing inside them and use valve cover spacers? Because the spacers are usually $110 so I may just say the hell with it. I'm still finishing up stuff with the motor, so its not all finished in a lot of the photo's
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