Chevy & GMC Vans

How long ago did you talk with the vendor on those Pro coms? If it has been over 6-8 months then it is a different world in product. They are made in Astrallia.

4.10 and remember mine is a AWD so it is front and rear. Power range? Not really sure. I don't want to run over 5800 rpm so the cast crank should be ok. I would like to get the most HP and torque out my setup not that i'm going to race it or do the strip. 350 to 400 hp if I get the chip, programming and the TBI stuff worked out. The cam really isn't a full out race but it is more than street performance.

Remember this is a do and learn project....

Planning on 31" tires...

I would get either a new style head or and old style head and not worry about a dual bolt pattern head.

I have had the most fun with Vortec style heads (stock, GM performance and Edlebrock). I have run the Edlebrock 200cc Etec heads and they flowed better than any other head I have ever used. I have run them in a few different combinations of engines (350,396,406), different cams and also some different compression ratios (9.0-1, 9.5-1, 10-1, 10.5-1, 11.5-1). They worked well untill I ran my ultra high compression engine combo in the summer and damaged it while on holidays. I had a hard time getting the proper fuel for it...AV gas worked well but I had a fun time begging for it! Add to that we broke a few rads, diffs, CV shafts and then over heating it and damaged a fire ring. It was fun combo to drive but it broke too many parts. I am now running a smaller engine with less compression and a different cam. It makes more low end torque but less top end hp. Still over 450 hp. It does almost the same 1/4 mile time as one of the high hp cams that I have tried. I am using 65cc GM performance cast iron Vortec heads on this combo. I changed springs and retainers to run more cam. These heads work well but do not make quite as much hp as the Edlebrock ETec 200s.

If you can afford some Etec heads and a new Dual plane Dual quad Vortec style manifold you could make some serious hp with a 383. I guess it depends on how much your budget will allow. Or just keep taking your time and buy a piece here and a piece there till you get what you want. Go with a high lift roller cam with short duration. I had great results from useing Competition Cams. They have come out with many new cam profiles in the last few years so you can almost build anything you can dream up now!

Jinmajay wrote:How long ago did you talk with the vendor on those Pro coms? If it has been over 6-8 months then it is a different world in product. They are made in Astrallia.

4.10 and remember mine is a AWD so it is front and rear. Power range? Not really sure. I don't want to run over 5800 rpm so the cast crank should be ok. I would like to get the most HP and torque out my setup not that i'm going to race it or do the strip. 350 to 400 hp if I get the chip, programming and the TBI stuff worked out. The cam really isn't a full out race but it is more than street performance.

Remember this is a do and learn project....

Planning on 31" tires...

Jim-I spoke to them last month.

I looked at the GM parts direct site and found two sets of heads:

Page one fast burn heads.Kind of pricey:

http://www.gmpartsdirect.com/results.cf ... 1&pkgid=33

These have 210cc intake runners and again I think it is abit big.Really a good read thro and it includes statements about 383's and test results.

Page two cast iron vortec heads. part number 12558060
Has 1.94 intake valves/150 exhuast.Seems kind of small.

Not sure which heads Rocky is talking about.Maybe he could post the part number.

Jeg's has a listing for the GM vortec heads and they have a 170cc intake runner.

http://www.jegs.com/p/GM+Performance/749896/10002/-1

Here from Summit is the Edelbrock E-tec heads.

http://store.summitracing.com/partdetai ... toview=sku

Yepper-I am picky about heads.It is a 200cc intake runner
and to me means the difference between them starting to come in at 3,000rpm vs one that come in at 2,000rpm with 195cc intake runners.I like heads with a sizeable intake valve(2.02 or 2.05) and a good middle point cc intake runner.Keeps the volume up and still have a smooth idle given what cam is in use.As far as a cam choice,with the extra cubes if a stroker,you can go bigger and still have a smooth idle.

Well alittle beat tonight,going to surf some more and then early bedtime.Talk to you soon.

Gary

Are the Etec heads worth twice the price? The Vortec heads just don't flow enough for this project.

The comp cam I purchased has a .510" lift on intake/exhaust and the advertised duration 276/290 and 220/230 at 050" of lift. Comp cam says that it is not to be used with computer control but I believe that means at factory settings. Its not a huge power producer but it is ay better than stock. The Etec 210 intake runners are really big for the amount of HP Im looking for. Is there a negitive effect if the runner size is too large?

And do they make a dual quad intake for vortec style heads? I thought most carb intakes were for pre vortec motors.

Jinmajay wrote:Are the Etec heads worth twice the price? The Vortec heads just don't flow enough for this project.

The comp cam I purchased has a .510" lift on intake/exhaust and the advertised duration 276/290 and 220/230 at 050" of lift. Comp cam says that it is not to be used with computer control but I believe that means at factory settings. Its not a huge power producer but it is ay better than stock. The Etec 210 intake runners are really big for the amount of HP Im looking for. Is there a negitive effect if the runner size is too large?

And do they make a dual quad intake for vortec style heads? I thought most carb intakes were for pre vortec motors.

Too large of a intake runner takes the torque curve and moves it up in a rpm range.What I am suggesting is a almost off idle beginings of the torque curve so it is almost always in the normal street driven rpm ranges.

Here is some formula's to look at to define torque/hp:

http://www.revsearch.com/dynamometer/to ... power.html

Check out this link for a buildup using GM Bowtie Vortec Performance heads. http://www.superchevy.com/technical/eng ... index.html

I used these heads for one of my last combinations. I installed different springs and retainers from Comp Cams as the stock ones were just barely suitable for my cam choice. These heads would work very well with your stroker.
https://store.gmperformanceparts.com/st ... 25534446-->

Here is a link to Edelbrock for their RPM and Etec heads.
http://www.edelbrock.com/automotive_new ... _rpm.shtml

I see the GMPP heads are 225 intake, Wow! I need to use a calculator to give me an idea as to what to shoot for on the intake runners. You guys must be one of them GM union workers $1500 buck for a set! Maybe I can wait until after the the failure of the bailout. Might could pick up some parts for cheap?

GEJ wrote: And do they make a dual quad intake for vortec style heads? I thought most carb intakes were for pre vortec motors.

Too large of a intake runner takes the torque curve and moves it up in a rpm range.What I am suggesting is a almost off idle beginings of the torque curve so it is almost always in the normal street driven rpm ranges.

Here is some formula's to look at to define torque/hp:

http://www.revsearch.com/dynamometer/to ... power.html[/quote]
Good site Gary!
This is neat.
Horsepower = torque x rpm / 5252

Here's an interesting bit of trivia; below 5252 rpm any engine's torque number will always be higher than its horsepower number, and above 5252 rpm any engine's horsepower number will always be higher than its torque number. At 5252 rpm the horsepower and torque numbers will be exactly the same.
:-k I didn't know that!~

Jim-
Here is the formula to figure out engine RPM while I talk to Rocky.

http://www.csgnetwork.com/multirpmcalc.html

Just plug in the values and it will give you the RPM's.

Did you guys get your Christmas cards yet?

Your the greatest!

2966 RMP with 4.10, auto and 31" tires. Does that seem high?

Jinmajay wrote:2966 RMP with 4.10, auto and 31" tires. Does that seem high?

Well here is the speed formula given rear end ratio and tire size,etc.That is the whole point of a higher gear ratio to get the power band at a lower MPH.The 4.10's will surely raise the RPM's sooner.It is not for a cruise over 65 mph highway long term.The 3.73's on the other hand isn't a bad trade off and gives you cruise speeds at 65mph and over long term.The point here is to tailor build a engine to the things you want the most.This is all part of the links section on this forum.

http://www.csgnetwork.com/rearendgearcalc.html




I think there are two approaches to building a street driven van.One being a hot rod that gas mileage isn't a concern,a higher torque curve isn't important,just getting as much as you can out of it is the main goal.The second approach is a daily driver that might not be as strong in the higher RPM ranges,but gives outstanding gas mileage,a more conservive build that gives outstanding perforance,has a torque curve within every day RPM driving ranges.One member here on this board that I have always looked up to for this kind of build is certainly SoCalli V8.With the Edelbrock system intake(which costs lots new,but you might be able to find used at a good price),cam choice,gearing,he still gets over yrs of use 22 mpg and has more than enough power to do whatever towing he wants.The other is Lockdoc with the crate build he did on the van Skippy bought.The other thing that has grabed my attension is Locdoc's honest opinion that mods you do add wear to parts like larger tires effect on parts.So the planning you do now is very important to what you want and the choices of what you want for the long run.From what I have read about Rocky's vans,he has surely built vans for max output given a street driven vans and a hot rod.One of the things I am looking into is,if given the raised intake runner of the new Vortec,gives a daily driver a torque curve in the lower RPM ranges.I am still digesting the link Rocky posted.So it is up to you to decide what kind of build you want.Either way-I bow to the build to someone who has gathered the info and followed thru with a game plan for the results they wanted.

Just use the speed formula and that will tell you how far away you are from the beginings of the torque curve.If it works out to be @ 55mph 2950 then expect using larger intake port runners to start at 3000 grand to 3500.There is a difference between torque beginnings and peak torque output.What I contend is street driven vans goal should be to get as much torque off idle as you can.There is torque is effect you want.A example of this is a brief ride I got in ZZ and Peter was driving.He burbed the gas acouple of times and oh ya you knew it was a 502 that would plant you into the seat.

Well it's getting late,ttyl.

Jinmajay wrote:2966 RMP with 4.10, auto and 31" tires. Does that seem high?

Don't forget you still have a 30% overdrive. Using the same formula and you will see just over 2000 RPM's at 65 MPH.

LiftedAWDAstro wrote:

Jinmajay wrote:2966 RMP with 4.10, auto and 31" tires. Does that seem high?

Don't forget you still have a 30% overdrive. Using the same formula and you will see just over 2000 RPM's at 65 MPH.

I thought he had accounted for the overdrive with his results. #-o

Rocky reminded me with my build of a 3/4 kickdown valve to use on my 700R4.I don't know what you could do to your newer style tranny to have the same results so it wouldn't kickdown until you pressed on the gas peddle 3/4's of the way and have the torque work for you.Let make this even more interesting.Look at the shift points and what would be the RPM's you going thru to have the torque curve work effectively for your normal driving around town.It does sound kind of expensive with a conroler of some sort,but yet still part of a combo to build for.I know Peter has something like that,but I am unsure how it works for electronic style trannies like yours.

Jim:plse note during these builds how good I and others are at spending other peoples money.(mainly your money that is):yawinkle:

The Compushift controller is for electronic transmissions and works great. Best money I ever spent. But yeah, it's pricey at $1,100. I think there are other outfits that make aftermarket controllers, but I can't vouch for their operation.