jay173

So I was thinking about changing the power curve by swapping cams , are the tpi cams compatible and what camshafts are best for tbi 305 engines?


I notice crane makes one for these engines tbi.

Atilla the Fun

You can change cams, but that won't shift the useful rpm range very much, because the heads and manifolding just don't flow well enough to support high-rpm power.
First do the 3" cat-back, then do a 3" cat, then do headers with Y-pipe. From there, do Edelbrock's Performer TBI intake manifold. Then you can get a pair of 081 heads. Then you can do an LT1 cam, and have high-rpm power.
At that point, you'll better gearing in the rear axle. But it should be your first mod if you don't have T-tops, and your second mod if you do. With T-tops, the first mod should be subframe connectors.
Don't start with the cam. You'll gain nothing from an LT1 cam in a stock LO3.

Chevy86 IROC-Z

iTrader: (17)

Is your engine an lo3? a cheap but hard to find cam that will give you a gain is a 4th gen Z-28 LT1 roller cam. Depending on the year of the LT1 cam, you'll have to grind down the dowl pin because it is very long on certain cams. If your lucky, you can find one for $50 dollars. But be weary because these are sought out cams and some will cheat you to make a quick buck by selling you a cam that is not what they claim to be.

BluFBdy

iTrader: (1)

i ended up going with the LT1 cam for my next motor, its s budget build so hopefully itll work out for me, id suggest following the above info, Atilla knows what hes talkin about with the TBI's hes helped me out a few times, best place to start is your exhaust like he said

rednekwizard

Crane cams still has a compucam 2000, thats what i got in my 86 Z-28 and it works and sounds alot better than the stock one did, that and the fact that my camaro now has a 350 from an 86 vette, but still same ecm W/jet chip add-on.

Chevy86 IROC-Z

iTrader: (17)

Our TPI engines are exactly that same blocks. The difference between our stock tpis from the vette are the heads. Vettes had aluminum while we got cast iron up until the late 80's IIRC. I think the CompCam you got is very good, but you would benifit the same results from a 4th Gen Z-28 LT1 cam because they are very similar to that cam you mentioned. I got a LT1 in my 86 IROC too.

rednekwizard

The good thing was that when they blueprinted the vettes block they put iron heads and the stock intake setup on it, my only problem now is trying to figure out why i keep tripping code 34 and getting it to pass smog.
How are those 22lb injectors working, mine has the stock in it and I was thinking of yanking some 22's off of a vette I seen at the local yard and swapping them out.

Chevy86 IROC-Z

iTrader: (17)

My Bosch III's? Man they are tha bomb. I love em. If I had money to spend, I de buy another 8 for future emergencies. I got em for around $160 from one of 2 sellers. Code 34? follow this link to find out the causes of your code 34,,,,,, http://www.gnttype.org/maint/malf.html

rednekwizard

Yeah, I got the book with the code reader, but I can't seem to find a good maf to replace mine,busted clip on the maf, I think thats why its showing low voltage.
I have a bosch(0280213009), with the five pins instead of three pins that I see on the ones autozone and checker try to sell me.
I googled the part number and the only one available is 700+ dollars.

Chevy86 IROC-Z

iTrader: (17)

Troubleshoot
your MAF before you go and buy a new one.

Chevy86 IROC-Z

iTrader: (17)

If the problem is the MAF Sensor, try this troubleshooting method first.
https://www.thirdgen.org/forums/tpi/...uble-code.html