:thumbleft: First I need help tring to find a good cam like the G5X4 Cam. I want that sound some what out of my L98. Then I wanted to know where to get a good set of 3.73's to go in my car. The car is a 91 coupe (red) and it is stock to the bone. Well I have SpinTech mufflers thats all. I don't know that much about vettes I am new to them, my friends hate me now cause I use to be a MUSTANG guy. Well I still have my 93 Cobra but I wanted to show my friends that vettes are badA55 too.

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If you're going to take the time to do the cam, spend the rear money on an exhaust, a tune, and heads. Port the intake yourself. You'll be better off.

What rear do you have now? Auto or Stick? The auto likes a 3.07 if that's what you have, I'd keep it.

If you are staying with the TPI and already have 3.07 gears then keep them. If you have the dreaded 2.59 then upgrade to 3.07's or 3.54's. I would do 3.73's with a miniram or LT1 intake or carb conversion only. If you have an auto then you have the Dana 36 rear and it will not survive for long with 3.73's if you start making more than stock power. Some have had success but most have not. These cars are light and have pretty low tranny gearing and therefore 3.73's or 4.10's make first gear a bear if not almost useless because of traction. If you are changing the cam I'd consider swapping heads too (or reworking the stock heads but it is usually more cost effective to buy better heads, new or used, or find used stock reworked heads), and having some portwork done on the TPI. If you are just doing a cam swap then I'd stay with something like the LT4 hotcam, no bigger. If you are doing heads and intake work as well then I like the CC503 cam, but no bigger if staying with the TPI setup.

You will get different advice as everyone has different opinions, just gather it all and make the best decisions you can.

3.73 is way too high. You dont want to go higher than 3.31 or 3.07 if its auto, and 3.33:1 or 3.45:1 if its manual.

If its auto, the money is better spent on a 9.5 inch torque converter to match the power youre making.

The L98 isnt a high end setup, its got alot of low down torque, and no matter what you do, youll never make alot of high end horses from it. I dont care what anyone calls alot.

No sense going with a really big cam with it (CC503 is not the right cam for this engine), cause youll never get the flow through the intake. Port the stock heads and go with a decent cam, and remember what ever you do, if you change the cam or anything else substantial, itll need to be reprogramed in order to run properly. If not, itll run fatter than the baker's wife at idle and low throttle, and only run any good while youre flooring it.

I have to say that Case is right as well. A higher stall torque converter will help alot, but don't go too high. My 2800 stall was too high for a TPI car, but it works great with my HSR intake. Also, I meant that with a fully ported, siamesed TPI setup with AS+M or equivalent runners the CC503 cam is as big as you should go (and yes, it is a little too big, but you said you wanted that sound, I'm assuming lope).

If it were mine and I was changing only the cam (which I wouldn't do) I'd slip a ZZ4 or slightly bigger cam in and run 3.07 gears with a 2000 stall converter. Add a shift kit, tranny cooler, and headers if the budget allows. Do some portwork on the intake, any will help.

If I were doing heads, cam, portwork and bigger valves on the stock heads or mild aftermarket heads and doing some major porting and such on the TPI intake I'd do a LT4 hotcam, 2400 stall converter, shift kit, tranny cooler (mandatory at this point) 180CC or so intake runner heads (or stock ported), and 3.07 gears. Could step to 3.54's but really wouldn't be worth it here.

Case is right that you really need to go to the next step past this and swap out the intake before the CC503 cam or bigger and 3.45 or lower gears will be best for your performance, but if you are looking for "that sound" then you aren't going to get it much with a hotcam. The hotcam is great for performance and has great street manners, not a lopey idle.

We are all assuming you have an auto. We are also assuming you are a street car looking for some performance. If you are looking for more of a drag race car then the TPI will always be holding you back. If you are staying with the TPI talk to forum member Josh, he has figured out ways to make the TPI fast at the track.

Thanks alot guys I KINDA understand what you are saying. I have an auto that is true but, what is the TPI ??? Like I aid I am new to vettes so everything is Japans to me. Ok see if I got this right put new heads on before a cam or anything else is done? What heads and where do I get them? Where do I get the 3.07's at, see my car just don't have that phll like my mustang on low end and I would love to have that. Thanks again for the input !!!

TPI = L98

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To expand a little bit. TPI means the Tuned Port Injection that's on your L98 engine. It's basically restrictive for performance purposes as it quits breathing at about 4800 rpm. If you're just staying on the street the TPI might work for you as you'll rarely, if ever see over 5000 rpm. Some performance gains can be had by switching your intake manifold and the tuned port runners that feed it. Like always, speed cost money.....how fast do you want to go?