Took my car to RPM to get dynoed and only made 415 rwhp. The motor is a 408 with ported l92 heads, g5x4 camshaft, about 11.1 comp., mac mid length headers. The car is a 98 ss camaro automatic with vigilante 3400 convertor and 3.73 gears with nitto drag radials. Really expected 475 to 500 rwhp. Car was smoking alot when jeff dynoed it and I later found out it was sucking oil through pcv in the intake. I took the car to the track and ran 7.41 in eighth mile at 94.5 mph. I had to really baby the car out of the hole or it would go up in smoke. My best 60 ft. was 1.75. I am fairly new at this ls1 stuff. Is this good performance? Why is dyno number so low? I see you guys posting 450to 500 rwhp numbers with older heads. Any input or advice would be appreciated. I am going back to brewers speedway this saturday with new 26 inch ET street tires so the car will hook. I also just installed NOS system and might try a 150 shot. I will post results.

 

Either dump the PCV system or fix that somehow so it doesnt suck oil... that will hurt you..

415rwhp is LOW... with that setup. Something is wrong.

 

First I would imagine you're getting a ton of knock retard if there is oil in the intake track. Combine that with your mac mid-lengths, G5X4 really isn't going to help those heads shine, auto, and your converter and you can start to see it adds up.

What exhaust do you have? What intake? Seems like you have a big can of worms with all the mis-matched components.

Nate

 

IMO, you should figure out why your car is smoking, why its producing such low numbers, and track times before you go off and spray it. There's obviously something wrong if its smoking. I can't troubleshoot your car from a computer, but my guess whatever is causing it to smoke is probably why its not putting out the numbers on the dyno or the track.

 

I ordered a oil and air seperator to put in pcv line . Right now I just have a breather in passenger side valve cover.

 

Well you do have an automatic which dynos lower than a 6 speed. I also see you are running midlenght headers. That motor needs to breath beater. Swap to a long tube and you should see some gain there.

 

Don't bother. Just delete the PCV system entirely. Put a breather in the fill cap and plug all other holes. Done and done.

What exhaust do you have? What intake? Seems like you have a big can of worms with all the mis-matched components.

Nate

 

Ditch the MAC's and Nittos. They are pretty good for a bolt-on, stock cube car, but will not maximize your current setup. Get some long tubes and switch to MT ET DR's to hook better. That should give you a better idea how good your setup really is. I would hold off on the nitrous until you get the engine sorted out. Are you using the stock PCV system and still running cats?

 

Jack, get some damn ET Street radials and be done. It will hook and you will have yourself some 1.5 sixties.

BTW, this is Jamie and I'm going to drag your *** with my vette

 

The the exhaust is mack off road pipe with magnaflow cat back. The intake is the l76 intake and I used 36 pound injectors. Also have holley 90mm throttle body. What should my ET be at drag strip in a full body camaro if I had 500 rwhp?

 

I would assume an L76 intake.. yeah the G5X4 is kinda small for a 408... But it should still make more. Yes the Mac headers will hurt too... It could just be a mismatched combo. Buddy of mine gained 10rwhp by ditching the PCV cause his 402 was sucking oil badly... I removed my PCV as well.

 

I would think the cam would be ok in that combo. The X cams have fairly wide splits on them, so that should help with the poor exaust flow. However, the poor exaust ports coupled with the poor flowing mac mids is what is probablly causing the low numbers. Your severly choking the motor with a header that can barley support a stock LS1, much less a 408 with big heads. Figure out your PCV problem and get a nice long tube and your numbers should rise alot.

 

Those numbers are low my ls1 with stock heads makes 405rwhp all on the motor. what color is the smoke white, blue or black? is it burning coolant, oil or is it running too rich? all can hendre performance.

 

Get yours out the shop first then meet me at the track but leave that NOS bottle at home.

 

It's out of the shop and ready when you are, bottle or not.

 

I understand you have an L76 intake...what is in front of the intake? Stock maf? Dirty filter? That car is going to be severely choked with that exhaust. Post a dyno sheet so we can see where it is falling off. Also do you have a flow sheet for your heads? Who ported them? What size runner did you end up with? And lastly what rwtq did you put down through your locked verter?

Nate

 

Also how do you know you're at 11:1 compression? How much did you take out of your piston and how big of a chamber do your heads have?

Nate

 

You say "about 11:1 compression. What are the numbers? Pistons reliefs? Milled heads?

 

This isn't a mustangdyno is it? Can we see the graph? Did they tune it? How much timing? A/F ratio?

 

Has a fully ported stock MAF, clean k&n filter, heads were ported by a friend who I know does really nice work. He really did not do much at all on intake side except around the guide and throat area but on exhaust opened them up to gasket size. I didnt take time to get them flowed cause the progect took more time than I wanted already. Have had three sets of heads ported by same guy in past and always had very good performance from his work. Guys at RPM forgot to give me my dyno sheet but I remember it made 405 ft. lb. of torque at around 5200 rpm I think. I remember him telling me it was using 90 % of the injectors if that means anything helpful. And also remember him saying torque convertor was NOT locked.