Hotcam?

[scotts94_z28]

ok so i want to order the LT4 hotcam package from www.samtaylor.com but ive heard that you must convert to the vented opti? Is this true and if so how hard is it to do?

[raroZ28]

I thought it was a straight swap and somewhat of an upgrade. Just wait for Joe to see the post, he'll know what's up

[Formulaboy95]

I am not exactly sure, but this is what I got from www.gmpartsdirect.com
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(From Gmpartsdirect site)
For LT1 and L98 engines 1995 and before, the dowel pin in the end of the camshaft must be pushed in so extension from end of cam is .30+/-.01", the same as the production part. For 1996 LT1 and LT4 engines, the dowel pin is in the correct position, extending .620" from the end of the camshaft. This camshaft has a fuel pump lobe.

Distributor Seal(1995-1997 cars) P/N 12552428
Distributor Seal (1992-1994 cars) P/N 10128317, but only one of these is used depending on application
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hmmm.... I don't know if the vented opti it is required to do the cam, but probably a good investment. Depending on how old the opti is, might just be worth upgrading if the cap/rotor section is worn out. Vented opti's are much cheaper than the 94 style, and USUALLY less prone to moisture failure. I think I paid around $190-210 from Jason Cromer at Sam Taylor.

Can anybody verify this? I think I am correct.

While you are in there it is suggested that you upgrade/replace the stock timing chain with the HD one. "Extreme Duty LT1/LT4" P/N 12370835

[scotts94_z28]

my whole ignition is new this summer so id like to just swap the whole kit in but someone told me i HAD to have a vented opti to do so but if not il just put the kit in. Also if anyone could give me some ideas on where to get the car tuned afterward in the rochester area it would be greatly appreciated

[Formulaboy95]

I have heard nothing but good things about pcmforless. Met one of their people at SLP day, and he was running 10.60 on the bottle. Helped me out alot, and was a great person to talk with. If you have a laptop, and get a cable from akmcables, you can program the pcm yourself. It's a great deal.

1994 and 1995 "Load your self" $50 if you purchase a loading cable from http://www.akmcables.com/ and load the program yourself. More details on this service are at the FAQ page.

Add $25 for unlimited updates for new modifications with the email package.

So you don't have to remove the pcm from the car and wait for shipping. The pcm upgraded tune is only $50, and they email it to you

pcmforless

[Injuneer]

Here's an online guide to swapping the vented Opti into a 93/94.

http://para.noid.org/~muttvette/opti.html

Note that next to the pictures of the differences between the 93/94 cams and the 95-97 cams, it includes a note that confirms the information above regarding the dowel pin:

Here's a 97 camshaft on the left with the longer cam pin and the hole in the center to receive the optispark. An early cam can be machined to match this, but free stock LT1 cams seem to be readily available from fellow f-body list members. The cam on the right is a 93 cam without the center hole and with the shorter drive pin. A late cam is compatible with an early optispark as long as the cam pin is installed at the correct height.

[94 formula]

Can't you just shorten the pin?

[AmericanZ28]

Can't you just shorten the pin?

I remember hearing that the pin can be pushed in to the appropriate length. Maybe a small hammer?

[scotts94_z28]

anyone know how to shorten the pin length for sure? also how hard is it going to be to swap all of these parts in?

[RocKin1967]

prices from these guys have been less than other places i have found maybe it will save u some cash . www.sdpc2000.com

[fastTa]

anyone know how to shorten the pin length for sure? also how hard is it going to be to swap all of these parts in?

Most of the guys that I know that have done this swap have used a die grinder and simply ground the dowel pin to the appropriate length.

[Joe 1320]

Most of the guys that I know that have done this swap have used a die grinder and simply ground the dowel pin to the appropriate length.

Yup. And make sure you take off enough material. If you don't, your opti will self destruct from the added thrust pressure.

[todd200]

When I swapped mine in I just pulled the dowel out of the cam I was replacing and put it in the Hotcam.