Why are lines so jagged and the power just drops off. Timing was at 24.5, a/f seems pretty good. how do i improve high end power to about 5800-6k rpm? How are these numbers compared to stock #'s?

 

What are the cam specs and the rest of your full mod list?

 

all mods are in sig, do you want the full cam card listing? Compresion 10.2:1 Thanks

 

You will need a different intake if you want the hp to keep climbing.

 

I dont see headers?

 

I do not have headers and i do have 33lb injectors installed that i forgot to mention. My thinking after talking with cam grinder and head guy was that 1400.00 for dynatech and y-pipe with high flow cats was not worth 10-15hp! plus I have had bad luck with headers 30 yrs ago and they were leaking, lose bolts all the time. I will install them if some one can tell me how much I'm losing with them! I'm going to install some cnc ported stage 2 heads and try to have Charlie change a/f and timing a little! Stock truck intake flows 280cfm i'm told and the 280cfm will make more hp than 297rwhp. Ive learned alot from this forum and please correct my old way's thinking! I need to get this figured out soon. It seems to never end!

 

The more you do on the intake side, the more that stock manifolds are going to kill your numbers. You don't have to use a $1400 set of headers, buy some pacesetters and y-pipe for 1/3 that price. When you swap out your heads i bet you will see at least 20hp from headers. An LS6 intake would definetly help out your top end power as well.

Were the pushrods in your sig recommended by the cam manufacturer or did you use a pushrod checker to find the length you needed? I just very rarely see any combo that needs something besided a 7.400" pushrod. Also that cam is awfully small for a N/A 6.0 in my opinion.

Also, don't let an experience from 30 years ago deter you from doing headers now. Thick flanges and better gaskets, along with locking header bolts will make them worry free.

 

Its just a poorly matched setup.

Ive got a similar cam single patterns are designed for use with a good exhaust. Id expect more to the tune of 30-40rwhp from lt's and an open exhaust with no cats.
If you want to keep the stock exhaust Id be swapping the cam for an ls6, lpe gt2-3 or the good ole 210/218.

The cam doesnt make sense to me. I think the duration and lift is fine but the ve's he's using dont add up. If it were on a 110/110 it would have made alot more power throughtout the rpm range.

 

Get v-band clamps welded on and oyu wont have the leaking and bolt problems.

 

I used 7.400 at first because of the head mill job and gasket thickness, then the grinder also cut base circle down to compensate. then valve train was noisey when engine was hot and quite when cold (drove me crazy) its alitlle quieter know but not right. So new heads and poss cam again will be next if I can get some good advice from the forum insead of me just doing it my f----- up way. Will the pacesetters be noisey (echo sound) with cats in the y-pipe