Blue Whale Vortec TBI

BLUEWHALE.jpg (54590 bytes)

I am going to leave this project on the website a while longer as I have used it for reference for showing 4×4 guys the importance of good gearing and this project had some good low rpm horsepower data since it was a 5spd truck.  But the camshaft is impossible to find and these days I can get nearly the same power from a stock L31 vortec motor which is the most popular setup I do chips for anymore.

if you like your trucks big then this is your ride. Like Ken Beals’ extended cab and long bed, it just doesn’t get much bigger.  Surprisingly, I put this thing on the scales and it only weighed 4700lbs with 1/4 tank of fuel even with the heavy campershell.    This truck doesn’t have too many frills.  No carpet no power seats, windows or locks, and an original 5 speed NV3500 transmission and stock 3:08 rear gears, but it has some power where it counts; under the hood.   This project may interest many of you who are looking to keep your old truck but the engine is old and tired and you would like to replace that engine and have a truck that performs even better than the newer 300hp Chevy trucks without screwing up your gas mileage or taking on a big new truck payment. With gas prices the way they are, I find a lot of people are looking to this route for their old trucks.   This is just what Ken did with the Blue Whale and it’s turned out quite well.  Check out this project and see if it’s what you’re looking for.
Ken’s truck had 235,000 miles on it when he decided to swap out the original 350 for a low-mile 97 vortec engine.  He found it on ebay with just 34,000 miles on it when the balancer came off and damaged the nose of the crank and purchased it for just $250.  Ken bought a perfect standard used crank and balancer from Charlie Schildt in Staunton, Illinois, installed new Clevite rod and main bearings and a GM LT4 cam, put in a Summit high flow water pump and a double row timing chain, bolted it together and was ready to go.  But, after putting it all together in the truck, using “another guy’s” chips, he just couldn’t get it to run right.  Ken called me to discuss his issues and I tuned a chip for him that made his truck run a lot better but it just didn’t have the power it should have.   As it turned out, Ken was deploying to Iraq and I agreed to play with it and get it running the way it should while he was gone.  Now that I believe we are there, here is the configuration as well as the problems encountered with it.
1. Just a pretty much stock vortec 350 with the stock GM LT4 corvette cam and 1.5 rockers which is pretty close the same specs as the LT1 cam, but the LT4 is a little more aggressive on the exhaust lobes to help complement the excellent flowing intake side of the vortec heads.  The specs are 203/210 duration @ .050″ with .477/.480 lift (based on 1.6 rockers) on a 115 Lobe separation.  The 1.5 rockers get the lift down in the .450 to .460 range, right in the max safe limits of the vortec springs and guides.
Nice mild setup, no head porting or larger valves or anything like that. Sounds very stock but sure doesn’t behave stock other than perfect driveability and excellent gas mileage.
2. Ken went the 50 state legal route and used Edelbrock’s vortec TES headers for a 96-98 which has the provision for the EGR tube and has the tube plumbed to the GMPP intake but he used the carb intake with Holley 17-45 TBI to carb adapter instead of the TBI vortec intake.  Design is basically the same though.   While he had it apart, he installed a new Centerforce clutch and pressure plate as well.
3. For the throttle body, Ken went with a turbo city bored throttle body which I believe is a 46mm bore and used the Holley powercharger (salad bowl) on the bottom of his stock air cleaner with a K&N element and a straight tube no baffle to the fender.   This air filter setup which I have in my recommended modifications at the moment for the 4×4 guys proved to be very restrictive and cost us 18hp and 15lbs of torque on the dyno.  The current dyno graph was run with the lid off the air cleaner assembly.   This turned out to be just one of the problems I discovered with the Blue Whale.
4. For fuel, Ken had already installed a set of 454 injectors which looks like, based on this project and the Black Magic project, today we run this configuration with stock 350 injectors running at 18psi of fuel pressure utilizing my custom chip kit. The stock fuel pump turned out to be one of the main issues when this truck was brought to me to fix.  Even with this mild setup we were loosing fuel pressure quick by the time it got to 3500 rpms under WOT. I installed one of pumps from my kit and the fuel pressure went to a constant 28psi which is too high so the adjustable regulator had to be altered showing just how weak that stock pump was.
5. Exhaust.  This turned out to be another one of the major issues with this truck since I took on the project. When it arrived, I would have sworn the plug wires were crossed or something major was wrong with the ignition system as it obviously wasn’t running right but the data recorded with the laptop all looked fine.  I checked the plug wires 2 or 3 times and I changed the plugs and I even removed the headers and did a compression test on the motor.  At a glance, Ken’s exhaust made good sense; efficient mid-length headers, 3” high flow CAT to a 3” Flow Master muffler.  However, while I was messing with those headers, I noticed the shop that had connected Ken’s headers to the CAT had made their own Y pipe and ran dual 2.25″ pipes and just T’d the passenger-side pipe into the driver-side pipe and then ran the single 2.25 driver-side pipe on back and flaired it for a 3″ cat, then ran 3″ back to a flowmaster and then stock duals from there back to behind the right rear wheel.  This setup isn’t all that different from the crap that GM did to the TBI Camaros so I didn’t know if it was really a problem or not but I knew how much the new Y pipe setup worked on the Black Magic truck so I asked Ken if he would like to experiment a little with a new exhaust setup as we both suspected the exhaust system.  He agreed and I had the muffler shop run dual 2.25″ pipes (should have run dual 2.5″) back to 2 flowmonster mini 2.25″ cats and then back to 1 awesome Dynomax Ultra muffler which has dual 2.25″ inlets and outlets but has an X pipe built into the muffler so I can get some exhaust scavanging through that muffler.  Exhaust was a little quieter than expected but sounds nice and the performance is night and day difference.  I would say this truck picked up even more hp than the Black Magic truck did with the exhaust change.   Ken had already done a 3-wire heated 02 conversion which is always recommended on all projects.
So if your going to make any real power with these TBI trucks you definitely need to change out the exhaust.
6. This truck is still using the factory mechanical clutch fan, radiator, and standard accessory pullies and Ken has never had an overheat problem with this engine, even when pulling his 4,000 lb camper on hot summer days.  The only modification Ken did was to swap the original steel accessory cradle for the 90-95 aluminum accessory brackets and eliminate the AIR pump.   I did install an MSD Blaster coil in his truck along with some AC Delco R44LTS plugs gapped at .040″ to ensure there wouldn’t be any ignition issues.
This motor should be relatively inexpensive to build since there is no expensive machine work done to the heads…it’s basically a stock vortec 5.7 long block with an LT4 cam.

This truck pulled 255hp and 315lb of torque at the rear wheels on 87 octane gas and if you figure a 15% loss through the drivetrain which I think is a bit too conservative on a truck with an 8 ft long 2pc driveshaft you get 300hp and 370lbs of torque at the flywheel. This is pretty close the stock horsepower of a new 5.3L V8 (which I don’t think you can achieve without premium fuel), but the torque is substantially better.   Not only is there gobs more torque but check out how flat that torque curve is.  That thing is pulling 270lbs of torque at just 1600 rpms where I started the dyno pull and by 1800 rpms it had 300 rear wheel lbs of torque which is better than the stock 7.3L turbo diesel that I strapped onto this same dyno for my tests on the website.   This combo should make a sweet 383 combo too for some really impressive torque numbers.   Just for reference, a stock 210hp 300lbs torque at the flywheel 350 pulls around 150hp and 250lbs of torque at the rear wheels.  I had another customer dyno a bone stock truck for me before he went modifying it.  This motor also pulled strong to well over 5,000 rpms.  For a sweet street setup, if you’ve got the stock 5 speed transmission, try this setup with 2:73 gears and you’ll have plenty of power with all that torque and gas mileage easily into the 20s.