[ChadTanner]

Hey guys,I try to answer all of your questions in some kind of ramdom order.

It's been over a year,since I have purchased any kind of regrind from Delta,but at that time the 4.9 cam had a $40 core charge,so after shipping and after the core was credited,the total was about $170.

My custom grind has 12 degrees more duration@.050'' lift,that is the only difference between it and the delta street cam.I wanted a noticable lump in the idle,which the other cam does not have with only 5 degrees over stock.I did not want to go as high as 220 like the E303,because it may be too hard to tune the caddy ecm and or may not have enough low rpm vacuum to use the caddy ISC,as It's desigined for a substantial and stable vacuum source,unlike a common IAC.

I hate to think,but would think my grind will yeild some kind of Gain.

About the 180 degree headers,I like the even fire sound,I've seen and heard many SBC engines installed in kit cars,with a "bundle of snakes",they do sound very "euro" or "V12",as opposed to "muscle car" or "bob truck".

The Delta "street cam" is a drop in cam,It's only 5 degrees over stock,which makes the overall duration still less than most stock V8s and it has no noticable lump in the idle.The cam does however yeid real world gains in TQ and HP due to the substantial increase in net valve lift.It requres no ecm tunning and does not change the RPM range.

Changing the rpm range of the 4.9 is a huge subject,here is a post, I made on another forum that would be very relavent to this subject.

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Turbocharging the 4.9 is a very interesting subject.I've done alot of research and put alot of thought into it,over the past few years.There has been so much Discussion about turbocharging the 4.9,that I am amazed that only one person has completed one.I guess the aggravation of tunning such a beast,deters many from attemping the project,but I can understand,if a person was looking for all out power,there are so many eaiser alternatives.
It's not a project for people that want to go fast for cheap,or the people that want to go fast on a unlimited amount of money. I guess that leaves a small group of innovative tinkers,The kind of intelligent creative people,you use to could read about in poplar mechanics,and there is always going to be a few total "nutjobs" like myself.

I praise "PBJ" for what he and rockcrawl done with the 4.9,untill someone overshadows them,they will be famous,till the day,the last 4.9 goes to the aluminum recycling plant.

The problem I have with all the 4.9 performance threads and turbocharging discussion,It's the same thing over and over.People say,,I want my 4.9 to breathe on the top end,and I want to accomplish this by adding a turbo,that will have some lag,and spool late.This makes great sense,because the 4.9 is a torque monster,and has plenty of tire shredding getty up of the line.Who would notice any boost lag? then the turbo will spool late and make this boat anchor breathe at high rpms.

It's the same story with the NA performance 4.9 guys,I want the engine to breathe on the top end,and make more useable power.I want to change the cam profile to move the power band higher into the rpm range,The engine makes so much low rpm torque,that I would like to trade some of that for some high rpm "useable" horsepower.If I could mod the engine to rev to 6500 rpm,look how much useable power I can make.

All of this should make sense to everyone,as this is just hotrodding basics,this has been the standard of making usable power since the birth of hotrodding.Anyone even thinking about modifying an engine knows all this stuff.The first thing you learn in hotrodding 101,is a engine is a air pump.You can obvoisly flow more air by modding the pump to turn faster.

Aside from all this basic knowledge,there is so much proof. All the 4.9 dyno sheets,showing the performance gains of custom cam grinds,ported heads,larger valves,custom throttle bodies,and ect.Also the proven real world results,like some 4.9 NAs running low to mid 13 second qaurter mile times,and the mind blowing sub 12 sec her86gt,now thats some respectable gains!!!!

Why would anyone dispute such cold hard facts?

I guess this is where you confirm your suspicions of me being a Nutjob. After two years of researching the 4.9 ,along with hands on experience tinkering with them.I have never seen anyone effectively move the peak horsepower up the RPM range,more than a few hundred rpms.That was only achieved with a large cam "220 degrees @.050 ramp" Some people would consider that a race cam.With minor to major porting, a small cam,larger valves,etc and everything else someone could think of bolting on,It seems the peak torque and peak HP are almost in the exact same place they were from the factory. Although they have been increased,they have not moved up in the RPM range.Aside from the peak power levels not being moved,the rate of which the hp falls off at high rpms,is not changed that much.Even pete's turbo 4.9 dyno shows what I call the "big plunge"

Now your wondering what I'm going to say about the quarter mile times "real world results".I know it's only my opinion,but I'm convinced of it. Pete's turbo 4.9 made 12sec passes because of the torque and horsepower gains in the engines original power band.meaning from the converter stall speed up to not much more than 4100 RPM. Is increased power in the 4.9's stock RPM range "usable power" ???I sure think so,and I am convinced that car was proof.

After so many talented people have had their burrs inside a 4.9 head and intake manifold and including all the other flow improving mods.I have seen no proof of any substantial gains above 4500 rpm.This is why I must ask....Why would anyone consider reving the 4.9 over 4500 rpm?

Another belief of mine is,,The intake and exhaust pulses caused by the geometry of the 4.9 is hindering the flow at higher RPMs,I also think the 1990 4.5's geometry would flow more air through the same head at high rpms,but I have not seen many dynos of that engine to be sure,but it sure looks good on paper.

If your still not sure if I'm nuts yet,this will seal the deal!!
My ideal for turbocharging the 4.9,is to use a small turbo that spools quickly,making max boost at about 3000 rpm.I know thats crazy!!! I think amplifying the peak torque and peak HP in their respectable rpm range,will yeid huge gains,but is that "usable power"??? Like I said before,I think this power is what made pete's car run a sub 12 sec pass.