I might purchase an LT1 cam for $20, but I have a question, Doesn't LT1 engines use optispark instead of regular distributors? If so, How does this affect my tbi car? If it doesn't have an affect I'll do the swap anyways..

 

yes
makes no differance. The only differance is that their water pump is cam drive insted of belt driven. You need to get rid of the little bushing that is on the cam that drives the LT1 waterpump. If you don't, you will make a mess. Its recomended that it is ground off but maybe you can pull it out. I dunno.

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-Tas
'89 Formula WS-6

305, TBI, auto, 14x3 chrome flat based open element with K&N, Milodon 160* thermo, functional Formula hood, cross-flow Flowmaster, '99z28 rear pipes and tips....

To be installed eventually far far far into the future: Yours if the price is right and I don't have to ship :
Hooker 1-5/8" 50 state legal headers, Dynomax 3" I pipe (PN 44063 and 43248), Catco 3" cat, and injector spacer.

Super GRK_Taz World
F-Body Dual Exaust
EFI & Intake Options
AOL IM: superGRtaz

 

What LT1 cam are you getting? There were only about six different grinds.

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Later,
Vader
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"Let the bodies hit the floor!"
Adobe Acrobat Reader

 

I know that it sparks a question or two in my mind. Does the LT1 cam have a distributor gear on it? Is it bronze? Will it run a mech. fuel pump (for use on a carbed car)? Will it cause a piston/valve slap problem in the L03? Will it cause retainer/guide bind with the L03 heads?

I have been interested in doing this swap myself, but have always had these questions in the back of my mind. I have read that the stock springs will work OK. But I would replace mine anyway just cause I'm sure they're worn out. Or should I get the Z28 springs from Powerhouse? Don't the Z28 springs have a 1.25" diam? Or are they larger?

Thanks
AJ

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92 RS w/t-tops 305 TBI Auto.
170K miles and don't burn a drop o'oil
-K&N Truck filter #1500 w, open ele.
air cleaner
-Dynomax 2 1/2" cat-back
-B&M TransPak
-Jet Stage2 Chip
-180* T-Stat w/ 185* Fan Switch
-JVC CD--Alpine speakers & 4ch. amp
Rockford 2ch. to 2 MTX 12" subs

 

just curois here , i didnt know there where 6 different kinds.. i am installing a stock roller cam out of a 96 Corvette/Camaro in my 305 tbi. do you have the specs for that?? how is it different form the rest??

thanks

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91 camaro RS
- 305 TBI
Mods: Performer TBI intake, 1" TBI spacer, K+N, jet fan switch ,160 thermo,Accel control module, Jet Stage 2 chip, edelbrock TES headers, Compleate 3" Flowmaster exhaust, Edelbrock springs, KYB struts and shocks, 700R4 built by TSI, SLP tq converter, b+m trans cooler, white guage faces, megashifter..
next month: spohn LCA's and panhard rod, BMR relocation brackets, 323 gear, lt1 cam , 350 heads

 

Im fairly certain that the Camaro and Vette cams were always different in the LT1 years, but in 96 didnt the Vette only get the LT4?

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Chuck Kulchar
1991 RS
Open Element w/K&N
3.42 - posi - disc
3" cat and Force II cat-back

 

I went into my local Performance Unlimited, and the buddy of mine that works in there said that Comp Cams just came out with a cam specifically designed for our cars. He said it requires no computer mods, but only makes power to 5000 RPM. SUPPOSEDLY, it is the best cam to get for TBI cars.

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1991 Chevy Camaro RS TBI w/auto
Mods:
Edelbrock TES Headers, REALLY high flow cat, 2 1/2 in catback flowmaster, 160 stat, hypertech chip, MSD ignition (rotor, cap, superconduct. wires), Bosch quad4 plugs, open air filter, all TBI mods, no smog stuff, no EGR, lots of suspention and alignment upgrades, and a big Chevy bowtie sticker on the back.

Fastest e.t.:
15.64 @ 87.8mph

 

Would you happen to have a model number for that?


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~Luke a.k.a. pianiy
'91 Firebird :: 305/TBI/700R4 ::
Mods: Catco cat - B&M Shift kit - TA tail lights - GTA rims - K&N - MacEwen guages
Stereo: Pioneer DEH-P8200R - Pioneer 6x9's - Kenwood 8" Tube
::R.I.P.::'87 Firebird - Firebird parts - Selling an '80 Firebird for a friend
Moderator of tranny board over at TransAmGTA.com

 

in '96 the LT4 was an option. Not standard.

 

92,

Sorry I don't have all the part numbers included, but here are the LT1/4 cam options:



Factory cams have no provision for a mechanical fuel pump, but Comp Cams replacements have a "lumpy for the pumpy".



Obviously, all LT1 cams have a distributor drive gear, since the gear is still required to drive the stub shaft that turns the oil pump. You would probably have to use a bronze alloy gear on the distributor shaft since the billets are hardened steel.

New87 installed an LT1 cam in his 305 with respectable results, and may have some insights about what things are involved with the swap.

------------------
Later,
Vader
------------------
"Let the bodies hit the floor!"
Adobe Acrobat Reader

 

Holy crap Vader - where do you get this stuff!? You're an encyclopedia of info. And you always seem to be right on with your advice. Thanks for what you bring to this board.

 

I don't think the stock grinds require a bronze dizzy gear. The bronze gears don't last too long and aren't used in stock applications. I believe most street roller cams have a cast iron tail section.

 

hey thanks for the info vader. that really helps me . i have been lookin for that info on my 96 lt1 cam for a while..

YOU DA MAN!!!

------------------
91 camaro RS
- 305 TBI
Mods: Performer TBI intake, 1" TBI spacer, K+N, jet fan switch ,160 thermo,Accel control module, Jet Stage 2 chip, edelbrock TES headers, Compleate 3" Flowmaster exhaust, Edelbrock springs, KYB struts and shocks, 700R4 built by TSI, SLP tq converter, b+m trans cooler, white guage faces, megashifter..
next month: spohn LCA's and panhard rod, BMR relocation brackets, 323 gear, lt1 cam , 350 heads

 

Picky points:

1. The 265 cid engine listed is called the L99 in GM enginespeak, so the table should really read L99/LT1/LT4 Gen II sbc GM cams.

2. The pn for the 12551142 is shown twice, once for the '96 LT4 and preceding it for the '95 LT1 w/1.6 rockers; I don't think they should have the same pns.

3. The cam specs for these two should also be a little different (they are listed as being the same with the exception of the LSA), though I know that the LT1 F/Y cams are very close to the LT4 cam.

4. The LT4 cam was mainly an optional Ycar engine but it did come in a small number of Fcars so it's not really appropriate to list it just as a Ycar cam.

5. The 94-96 L99/LT1 Bcar cam is also the 94-96 Dcar cam; i.e. used on Chevy, Buick and Caddy fullsize rwd cars. In addition, that cam was also used on the 96-99 light trucks using the L31 Vortec 5.7 engine.

6. The last two cams listed don't look like GM cams (maybe I'm wrong, but I don't recognize the specs), though they are probably correct for Gen II sbc applications.

7. I also don't see the GM (so called) ZZ3, 845 and 846 cams... all three of which are useful in 87+ sbc passenger car engines with hydraulic rollers.

I know you borrowed this table from another author (jlstrey) so you might fwd these comments so s/he can fix the original one. I tried to find an email address on the http://homestead.juno.com/jlstrey/ website but failed. Maybe jlstrey will read this in the meantime.

It would also be nice to see the L98, LG4, LB9 and other TPI and TBI cam specs along side those for the L99/LT1/LT4, because the cam question is one that get revisited to the point where the info should be FAQ'd. I think someone posted a request for FAQ items on the TBI forum, and this ought to include all the hyd roller cams for Gen II applications, and perhaps the 3rd Gen cams that are not hyd roller.

I have a massive cam file that originally came from Mark Boggs (I think) and it's been added to since. If I dig it up I will fwd it to you (you'll have to send me your email address though). - Ken

 

There are cams specs for TPI engines in the Cam Tech article. Some of them, at least.

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1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.23 @ 107.62 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Webmaster: SoCal F-Bodies
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