3.4L compression ratio..(and more cam frustration) VIPER inside!

[camaro28]

Viper,

First off, I am looking to getting the heads machined (shoulda done that when the motor was apart.. blew a head gasket). While i've got the heads off again, I might as well get em machined down to bump the compression. Can you tell me how much i can SAFELY get milled off the heads? Ive got the same cam as you got, heads have not been milled as far as i know/can tell. Any ideas?

Second, Im still running the stock tb, ported and polished some. Car still idles like ****, runs really really rich at idle. i got a BBK adj. fuel press. regulator.. got the FP at abotu 40-41 PSI. Ive got a small hole drilled in the tb plate, which helped a tiny bit. what are my options? bigger hole in the TB plate? I cant adjust fuel pressure any lower (regulator wont allow it). any suggestions? Thanks

[Tiago]

big cam will do that since we dont have programming.

tune your fp down to about 30 psi

[camaro28]

see, thats the thing,, i cant lower it any lower than about stock, as the BBK fuel pressure regulator just simply wont go lower than that.


Should i sell the BBK press. reg. and buy another one? IS there a specific brand that will let me go LOWER FP than stock?

[Tiago]

I know my Holley AFPR can go down

[camaro28]

hmmm, maybe i should sell my BBK one then. You got a link for the Holley AFPR? Perhaps a part number?

[3.4 slow to go]

Running this rich? the TPS was out of wack, might want to check/adjust. never know.

[camaro28]

hmm, possibly.. i never had stuff falling out of the tailpipes though, just black smoke at idle, and the plugs kept fouling out. How do you adjust the TPS?

[3.4 slow to go]

Ordered the sensor probe & injector/harness tester from SunPro & used the probe to adjust the tps. It eliminated all that crap shooting out the tail pipes. A new MAF also helped (but it never passed nazi e-check so I said F-it, I'll just put the 3800 in) . My plugs fired, but were always covered in black soot. Those bosch supers must be pretty impressive.

[mattsv6]

i have experemented with adyusting the tps and it does nothing once you shut the key off. o tried slotting the holes on the tps and it mad eit alot leaner, but once i shut the key off it resets itself. the problem is that the tps signal is just a reference voltage and you are tricking the computer into making it leaner. and btw, i had the same trouble with my bbk afpr, jsut take the old mounting ring off the stock fpr and use that as a spacer under the bbk piece. worked for me. and also make sure you didnt ruin the fpr diaphragm

[CamaroL32]

Like matt said just use the mounting ring from the stock regulator as a spacer for the BBK one. I had to grind down the lip on the edge of the stock ring to make it work, but other than that it worked fine.

[camaro28]

good call guys, sounds like a plan!

Ill get the heads machined and get the car back together and see what happens..


Now whose got some info for me about how much of the head i can get milled off without having mr. valve meet mr. piston. [img]smile.gif[/img]

[3.4 slow to go]

how much CR are you lookng for? After a certain amount milled from the heads, you're gonna need the base manifold milled to maintain a good seal. Intake gaskets can only compansate for so much.

I'd go maybe .030 max on them. Doesn't sound like a lot, but it is. & if you want, go .015 off each side of the manifold.

[viper98885]

I had my heads milled .005". I went with new pistons to mess with teh CR, not with the head milling.

AS far as the fuel pressure, you need to find some way, to get it lower. I have the Holley AFPR and it works fine, and I keep my fuel pressure around 30 psi or so unless I am racing, then I will turn it up a little. You should try to space it if possible.

Your other option would be to install the Holley Commander 950 Engine Management System Kit, you know, it you have an extra $1000 sitting around somewhere.

[ November 08, 2003: Message edited by: viper98885 ]</p>

[cammed3800]

where can you get the holly afpr?

[viper98885]

You can get it from us.