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TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

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Old Jul 31, 2008 | 02:57 AM
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TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

I have a '89 LB9 and I think I read somewhere the '90 had 230hp while the '89 had 190hp but both had the same torque ratings? Correct me if I am wrong, but does anyone know what GM did to make these improvements if there were any? Did they just use the L98 cam in the 305s which made the horsepower jump?

I just found out my motor was an '89. I bought the motor and the guy said it was a '90 :/

Is the cam I have known as the "peanut cam"? also will a lt1 cam fit in this car, or do people refer to their cam as an Lt1 cam becase it is ground to the same specs as an LT1. How is gas mileage affected with the Lt1 cam? Heads are stock and manifolds are stock, this might have been answered before but I cannot find those old threads, anyways let me know thanks. also say my motor is rated at 190hp what could it jump to?

Last edited by streetworkxs; Jul 31, 2008 at 03:07 AM.
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Old Jul 31, 2008 | 08:46 AM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

89 is 230 hp.


https://www.thirdgen.org/1989-chevy-camaro
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Old Jul 31, 2008 | 09:33 AM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

Or 195, depending on the cam, which depended on the trans.

90 and up were the only years that all 305's got the L98 cam. The low output ones during these years were the ones choked with single 2 1/4 inch exhaust.
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Old Jul 31, 2008 | 07:25 PM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

Does it matter which yr. lt1 cam goes in? What is a good year?
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Old Jul 31, 2008 | 08:14 PM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

87 auto was the only year for the "peanut cam", your cam is the same as the 350, Im almost sure no 305 came with 230 hp stock in a 3rd gen.
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Old Aug 1, 2008 | 08:30 AM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

Wrong and wrong.....

https://www.thirdgen.org/1989-chevy-camaro
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Old Aug 1, 2008 | 08:43 AM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

What's a "peanut cam"?
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Old Aug 1, 2008 | 06:28 PM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

Originally Posted by wanab03ss
87 auto was the only year for the "peanut cam", your cam is the same as the 350, Im almost sure no 305 came with 230 hp stock in a 3rd gen.
Don't be so sure, ALL the G92 cars from 1990-1992 with the 305 TPI had 230 Net HP ratings and most seem to do slightly better. The 1990-1992 Automatic cars had the very same camshaft (L98 cam) but ran a more restrictive single cat exhaust with smaller exhaust manifolds.
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Old Aug 1, 2008 | 09:19 PM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

Ok then ...right and wrong,, 87 was the only year for the peanut cam...... https://www.thirdgen.org/mods3... I thought 225 hp was the highest speed density gm offered... .... thats pretty impressive, no wonder why the 91 parts car I had bought felt like it would walk my 87 up and down the block.
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Old Aug 2, 2008 | 09:28 AM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

I still consider the 88 & 89 auto cars cams to be peanut cams.
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Old Aug 2, 2008 | 09:34 AM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

but its got more duration and lift than the 90-91,,,
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Old Aug 2, 2008 | 09:49 AM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

I was talking about the one that came in the auto cars.

87-89..... Two cams, L98 or peanut.

90-92..... One cam, revised L98
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Old Aug 2, 2008 | 09:59 AM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

87 was the only year for 2 cams and the manual was..alright. but 88-89 shared the same cam. as did the 90-91 I wonder if the lsa difference actually makes the 90-91 cam better for midrange?
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Old Aug 2, 2008 | 10:48 AM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

Originally Posted by wanab03ss
87 was the only year for 2 cams and the manual was..alright. but 88-89 shared the same cam. as did the 90-91 I wonder if the lsa difference actually makes the 90-91 cam better for midrange?
The 90-91 cams WILL make more mid-range torque than the wider LSA cars. The cam in the 305 in my Van is a Production LT4 Corvette cam on 203/208 on a 115* LSA, the thing FLYs. Torque across a wide RPM band.

This is me getting up to speed the other day on a ramp that is slightly uphill pulling a 3,500 lbs boat. The ramp is short and the traffic flows about 80+ on the freeway.

http://s243.photobucket.com/albums/f...t=101_1406.flv

This is unloaded launched at 1,300 rpm.

http://s243.photobucket.com/albums/f...t=101_1403.flv

Last edited by Fast355; Aug 2, 2008 at 10:55 AM.
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Old Aug 3, 2008 | 12:46 AM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

Originally Posted by wanab03ss
87 was the only year for 2 cams and the manual was..alright. but 88-89 shared the same cam. as did the 90-91 I wonder if the lsa difference actually makes the 90-91 cam better for midrange?
There were still two different cams installed in the 88-89 cars...

The autos had a variation of the peanut

The manuals had the L98.
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Old Aug 3, 2008 | 08:56 AM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

show me some info in it. Ive done internet searchs and found that GM offered 1 cam for 88-89 manual or auto. Im not saying your wrong, your just wrong till ya show me some proof..lol .... anything is possible but understand Im leary cause not only my own searchs, but I would assume thirdgen.org would have listed 2 cams for 88-89 if there were. Anything is possible but........
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Old Aug 3, 2008 | 10:00 AM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

Originally Posted by wanab03ss
show me some info in it. Ive done internet searchs and found that GM offered 1 cam for 88-89 manual or auto. Im not saying your wrong, your just wrong till ya show me some proof..lol .... anything is possible but understand Im leary cause not only my own searchs, but I would assume thirdgen.org would have listed 2 cams for 88-89 if there were. Anything is possible but........
G92 cars came with the larger exhaust and the L98 cam. The peanut cam went from 88-92 in the L03 and 87-89 in automatic LB9 cars, HP ratings consistant with its use. In 1990 when the speed density TPI setup came out the L98 cam was used across the board on TPI cars.
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Old Aug 3, 2008 | 10:13 AM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

So you have an article that states that? Everything Ive found says the lb9 88 and 89 305 and 350 have the same cam, the l03 is a different story . Im going to do more research on it but if you could find an article or something to prove what you say that would be awsome.... if you cant tell Im kind a hard head........I need proof, then I need proof that the proof is full proof...lol.
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Old Aug 3, 2008 | 12:38 PM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

Originally Posted by wanab03ss
So you have an article that states that? Everything Ive found says the lb9 88 and 89 305 and 350 have the same cam, the l03 is a different story . Im going to do more research on it but if you could find an article or something to prove what you say that would be awsome.... if you cant tell Im kind a hard head........I need proof, then I need proof that the proof is full proof...lol.
I don't need an article to tell me about it, I worked for a GM dealer and did all my research through their parts system.

The "155" peanut roller cam was used in

1987 LG4
1988-1992 L03
1987-1989 LB9 Automatic

The "773" L98 roller cam was used in

1987-1992 LB9 Manual
1990-1992 LB9 Automatic
1987-1992 L98 Automatic
1987-1993 L05 9C1 Caprice

Last edited by Fast355; Aug 3, 2008 at 12:42 PM.
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Old Aug 3, 2008 | 01:22 PM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

On a stock motor with the peanut cam what can I expect to gain by installing 1.6 rockers ?
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Old Aug 3, 2008 | 01:23 PM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

.. youve convinced me, Im suprised they dont have that in the camshaft tech article, oh well. thanks for the info. Now I know and knowing is half the battle.. G.I jo......
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Old Aug 3, 2008 | 01:30 PM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

Originally Posted by kanmudhog
On a stock motor with the peanut cam what can I expect to gain by installing 1.6 rockers ?
.373/.410" valve lift, and a few more degrees duration at .050. Its 176/194 now and the 1.6:1s might make it 179/197 or so. I would recomeend a cam swap to a more suitable cam.
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Old Aug 5, 2008 | 09:48 AM
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Re: TPI LB9 IMPROVEMENTS THROUGHOUT IROC HISTORY

Have you ever run a ZZ4 cam in a 305 Fast355????
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