TPI Camshaft Question
 

Hey guys I was wondering if this cam http://www.compcams.com/Company/CC/c...?csid=126&sb=2 will work in my 1986 IROC TPI without any other modifications or would I need a computer chip? Anything else that I'd have to do? I'm not familiar with TPI as this is my first third gen Camaro. I actually already have this cam. Bought it off of eBay a few years back to put in my 1986 K10 with a carbed 305 but I ended up putting a 350 in it and a much larger cam so I never used this one. I know the stock cam in these TPI cars are very small and that they had two different grinds they used but I haven't been able to find the specs on them to even kind of get an idea how much different in lift and duration this one would be. Thanks in advance for replies. Joe

Re: TPI Camshaft Question
 

Its 212/212 so its right on the border if you will need a custom tune or not. A set of good headers and a larger stall converter, like 2000-2400 rpms will help this as well.

Re: TPI Camshaft Question
 

As Kevin said that's right on the borderline of whether a tune is absolutely needed or not. With the MAF system you have more wiggle room, but a good tune would still help a bit. In order to get by without the tune, you'll need to bump up the timing a bit and run premium gas at all times. You'll also need to be able to bump the fuel pressure a bit, so I'd consider an adjustable fuel pressure regulator as a must.

Cam wise, the stock 86 TPI (10088155) is very, very small – I’m not so sure that it isn’t the same cam that was in the rather obscure 1975 and 1976, 110HP, 262. Duration at .050 is 179/194 on a 109 lobe spread with only .350/.384 valve lift.

You didn't mention or ask about this, but the cam you have would work with the stock valve springs assuming they're not high mileage and worn out. However, if you're going to take the time and effort swapping the cam, I'd recommend a fresh set of valve springs. I’d budget for a replacement timing chain as well.

Re: TPI Camshaft Question
 

Thanks for the replus guys as well as the info! I know a little 305 is very limited simply because of small displacement and very poor cylinder heads, then throw in a tiny little cam like that and, well you're lucky to really get much out of it. I don't really want to get too radical with it, but if I could make this cam work I'd sure like to run it even if it means putting a Jet Stage 1 or Stage 2 chip in it along with a 180* thermostat. Would I be on the correct path going this route? Or the other option would be to sell this cam and buy one a step or two down from this one and in that case which one should I look at, the next one down or two steps down?

Really the cam that I've already got, to me anyway, isn't that radical but I've always stuck with carburetors until this car came along. And I know a computer looks at cam size totally different than I do! I call this cam a very very mild cam since I run a 280 Magnum in my 86 K10 but again, it's carbureted and no computer to throw a fit! The TPI is a totally different animal that I've never messed with before but I've built and modified tons of these old Gen 1 small blocks in years past. It's the computerized part that's throwing me a curve. So should I be looking at the stage 2 chip or would it be too aggressive to use with this cam? I don't want to hurt the drivability but I'd like to step up the performance as much as I can all the while leaving the stock appearance on the outside. Thanks for the help in advance! Joe

Re: TPI Camshaft Question
 

Oh and I forgot to mention that I do have the matching springs for the cam as well as a double row timing set and even push rods and rocker arms so I'd be good to go on that end. I tend to keep quite an inventory of SBC parts on hand for when the mood strikes to make changes to one of my projects lol.

I went back to Comps website and took another look at this cam http://www.compcams.com/Company/CC/c...?csid=125&sb=2 but I'd rather use what I have and buy the corresponding chip to make it all work together. Btw the car has just over 113,000 miles on it. It runs great, doesn't smoke, rattle, have any odd noises and holds excellent oil pressure. Runs and feels rock solid. Just needs a little more in the get up and go! Joe

Re: TPI Camshaft Question
 

I swapped a lot of cams for myself and others in LG4s and L69s back in the day. I didn't mess with different cams in the EFI cars back then, but did a lot of "super tunes" that involved mostly "free mods". The 212/212-110 comp was the biggest cam that didn't need a lot of carb work to get it right. The TPI is a little different when it comes to "tuning", but I don't think you'll have too much to worry about based on the vacuum you should have with the cam you have now (212/212-112). That is as long as you're able to bump the fuel pressure a bit.

I would not waste a dime on a boxed aftermarket chip. I actually got into chip burning after buying a car that had a $350 custom JET chip and found that the stock chip ran better. Once I could read the JET chip, it was so messed up that I'd consider it criminal. It was the reason the guy had washed the cylinders down,, but it did allow me to buy the car on the cheap. Anyway, I'd say if the stock chip didn't work (I think it will), then break down and get the equipment to do the tuning yourself - if you did you wouldn't need the adjustable fuel pressure regulator then. It's really not all that hard to do and if you have a good basic understanding of fuel and spark needs, you'll be fine.

Re: TPI Camshaft Question
 

Thanks! That's some good information to find out! What would I need to be able to modify my stock chip? Thanks! Joe

Re: TPI Camshaft Question
 

Check out all the DIY PROM Stickies on this site - plenty of information that can sound a bit more complicated than it actually is. I had some anxiety at first, but after firing everything up and jumping on in, I kicked myself for not doing it sooner.

https://www.thirdgen.org/forums/diy-prom/

Re: TPI Camshaft Question
 

That's the same cam I have in my Monte Carlo SS TPI conversion. I think it's a really tame cam, I wish I had got the next cam in the same series, 212/218 @ .050. Right now I have the fuel pressure adjusted to 45 psi with engine off. The BLM's are about 128 - 130. I have a reprogrammed chip from TPI parts.net with corvette fuel and spark tables. I'm running a stock re-bushed throttle body, but plan to reinstall my 52mm BBK to see if there is a difference in performance.

Re: TPI Camshaft Question
 

Thanks for all the replies guys! I know it's a pretty tame cam but it should step the performance up considerably from stock and still sound stock which is what I'm looking for. The main area of concern is keeping the computer from throwing a hissy fit! I think you guys have me on the path I need to be on to make this happen! It's just a matter of putting the cam, lifters, and springs in and making the computer happy! Many thanks! This is a great forum! Joe

Re: TPI Camshaft Question
 

I have this cam and lifter kit in my stockpile as well. It's another bump up. Lunati Voodoo. http://www.lunatipower.com/Product.aspx?id=2323&gid=287