1991 TBI Setup Need tech HELP!

**dyeager535** · 10-01-2013

I don't know exactly what cam is in my Dad's 454, but I can tell you (and Mark can as well lol) that with a "computer friendly" (lie) cam, Edelbrock intake, and headers, it was about 20% lean. Took a fair bit of work adjusting the fuel pressure to get fueling back in line, and with as much work as I had to do to try and get fuel pressure up, any more fuel needed and it would have required a change of the fuel pumps.

On the potentially helpful side, I learned that if you have the OE 454 fuel pressure regulator that has the "window" where you can see the spring (some you can't), you can shim the spring until it's a hair less than at coil bind, and you will get as much pressure from the pump as it will deliver.

**Trentec** · 10-01-2013

The thought I have is that this engine is 52 cubic inches smaller (402) so maybe the fuel would be in the adjustable range. The last tune I had in it was bad rich pulled hard but left a cloud...lol What you said makes sense that part combo should have netted at least a 20% power increase or more. The intake needs to be changed due to an obstruction on the stock intake the EGR stuff I think but it's wide and flat and will collect puddles of fuel. So his thinking is that he wanted a cam and if he has to pull the intake off he's not doing it twice and I can't argue that point. That was the smallest cam at least in the group I looked at. my question is really about how friendly that particular cam is to the computer. Because power is nice but drivability ultimately is going to be more important.

**Fast355** · 10-02-2013

That should not be a hard cam to tune. I tuned more cam on a tighter lsa in a 305 running a 7747. Should idle all day at 650 rpm.

I think the rpm range of that cam is a lie or typo however I just don't see it making much power over 5,000-5,500 rpm. Definately not enough duration for 7K.

**Trentec** · 10-02-2013

5000 is all it will ever see and hardly even that, didn't think it would do much more with the 650 or so cfm. It's a lot more cam than stock so it should give him a little more pop. I just wasn't sure how the system would handle it.

Thanx for the input!