69 Mustang

I'm putting a little 355 together. 10:1 Compression. Worked Vortec Heads, SDPC intake, AS&M runners, ported base, 58 MM TB, 30 Lb injectors. here lies the problem. I wanna put a decent sized cam in there. My biggest choice right now seems to be the Comp Cams XE-268-14 at 224 230 on a 114* LSA. Would it take a custom grind? Such as a 226 236 on a 114*? or is that far too much cam for the computer to deal with? I'll be learning to burn my own chips, only cause I can't really afford a DFI system. heck, I can't really aford half the motor. But ain't that the way it always is. Any help and advise is appreciated. Thanks!

Grim Reaper

You should be able to tune that okay if you are burning your own eprom. Are you using MAF or SD?

new87

You dont have to worry about the cam messing with the computer, EVERYTHING else you have done is going to make it loose its mind no matter what cam you use. With all of your other mods you are going to need a custom PROM. Just to cover myself a bit, the computer may let the car run but not very well.

69 Mustang

I have MAF. If possible, I wanted to stick with it. For some reason, no matter what was going wrong with the car, it seemed to run well. I've run 15.7's in Limp Home .

So 87.. you're saying there's no way to get the car running optimally? i would thing all the other mods I have listed are standard for a TPI build up, Save for the Vortec heads and large cam.

fly89gta

iTrader: (1)

thats always the way it is Nate

a 114 isn't THAT bad for a TPI computer, talk to PK he'll probably tell you the same thing, you're gonna need a good chip regardless if u go with that cam or not...

Guest

I'm running a cam thats almost identical to that one. It will run with the stock chip, I'd suggest starting with an 89 chip with the VATS turned off and go from there. Its going to be a little rich at idle, so thats probably the first problem you will want to address.

new87

You are going to be flowing way better than any stock TPI. If you get your full timing and A/F ratio programed properly then you will be much happier. That stock chip just wont cut it. I did a cam swap and gained .5 sec's, with extra tuning I picked up another .5 secs. You got a hell of a combo there dont reck it with a stock chip.

69 Mustang

What I was trying to say in regards to the computer is, not if it needs a chip. Lord knows I would need one. But rather if the bigger cam will send the computer into fits regardless of the chip I get. PK was saying that I'd need at least a 114* LSA or else the computer registers the individual vaccum pulses and makes the computer go haywire. Are there any Cam NO-NO's I should know about with the TPI? Like don't go over .700 lift?

new87

I'm sorry, I see what you are asking now. That is a big one to much lift and the computer will throw a knock code. As far as the LSA just stay above 109 and you should be fine.

Guest

Knock code? From a cam? Thats a new one.

I would not worry about things like knock codes, or running bad to not running at all. Thats not going to happen. You can run up to about 218ish duration on the intake side and the chip will compensate fine. Beyond that, it will need a little messing with to get running right. I'm not sure theres any real limit as far as the ECM goes, but there is as far as using a TPI on top. The cam you suggested is far from ideal to use with a TPI setup, a smaller one would make more sense. Maybe with the heads, base (that I have not yet seen up close) and those runners it will work fine.

Chip tuning, to me, is sort of an aside. Any car will benefit from tuning, and the ones that are farther away from stock will benefit more than stock engines. They will all run, however.

new87

That was my problem after my cam install, but I guess I should try to work and answer question at the same time. I just didnt have my timing set right and that was my problem.

Grim Reaper

Tim (Traxion) is running a bigger cam with AFRs and a Miniram quite nicely on his 350. He is using SD, so with SD you will definitely have a solution.

But, since you are getting into eprom burning and the equipment all works with MAF and SD (you just have to buy the $8D TDF from Tunercat for $20) - try using the MAF first. Costs nothing and you may find it works fine. I have a friend using a similar cam (112* LSA though) with his MAF 383 Miniram with AFR 195s Competion Ported w/2.05 intakes. The only "tricky" part was compensating for lack of fuel (once the MAF was max'd @ 5,000 rpm). All we did was add more fuel via the PE %Change AF Ratio vs RPM table. He hasn't dyno'd his engine yet (will do that this spring) but he expects peak HP somewhere around 6,200-6,400 rpm.

We started with the 1989 ARAP Bin (like Madmax suggested above) and "tweaked" from there. We initially were planning to switch to SD, but the MAF has been working so well, we have put that off. As I said, you got nothing to loose starting with the MAF and if you do find driveability problems, then you can easily switch to SD.

360Iroc

i run a 264 cam in my trans am and dont have a problem on a hypertech chip, the only problem i has was the knock sensor picked it up, so i replaced it with a higher resistince sensor, everything runs fine, the cam is a comp 264 with .487/.495" of lift