Just wait till sean gets his beast rolling then you will get all the numbers and track times you want!:TU: But then again seans combo is going to be pretty radical lol so it wont be the best to judge off when he does get the skylark rollin:beers2: . Hey mark why is your car not running I thought I seen in a thread somewhere you dont have a tranny in it?What happened?To much :3gears: and she gave out on ya:TU: .
boost spooling also depends on youre rear gear ratio, youre turbos will actually spool up quicker if you have a 2.56 compared to a 3.42
Out of curiosity, why is this? Hadn't thought of that before. My initial feeling is that it would be the other way around. Devon
Well the good news is that I will run the stock 70 350 with the Turbos for a little while before dropping in the good engine, trans and rear end. I hope to chassis dyno the car with stock 350 and 8 psi.
Well, it's really only true if the tires will hold it. The thing about turbos is that they build boost based on engine load, not just rpm. If a car has good traction and runs a higher gear ratio, the engine lugs down compared to lower gears, which causes the turbo to respond at lower rpm. If the tires spin before the engine lugs, it won't bring the boost in as quick. That's why if you watch turbo cars at the drags, the turbos usually won't build boost in the water box until the tires are good and warm and start to pull the engine down. It is a balancing act though. Even with the quicker spooling and torque of the turbo, you don't want such a high gear ratio that it is doggy out of the hole. The hybrid turbos come on so hard that even with my 4.56 gears, I get boost immediately if I punch it.
What is the highest that you've boosted so far? I'll be doing the same thing soon with a stockish 350 and what to know if you've found a breaking point yet.
Thanks...that makes more sense now. Guys, we really need to be clear about things like this. The Turbo V6 guys have been doing this for many years, but here on V8Buick we are new to this stuff and can only rely on what you tell us. Devon
10psi on 87 octane. Only once, and for about 2 seconds. Didn't like that on cheap gas. 8psi runs great on pump gas no intercooler. I might slap an intercooler on this winter so I can run 12psi all the time. It's no so much the boost that kills them (to a point), but the tune, or lack thereof.
The breaking points of the 350 have been found already: The stock 73-80 rods are strong until about 600 hp maybe more if kept under 6200 rpm (lighter pistons help as well), the crank has held over 800 hp, the block is good up over 1000 hp. For this reason mark and I are using the $1300 forged rods and forged pistons in our good engines. I plan to keep my 350 under 7000 rpms, it is fully balanced, rods are 90 grams lighter than stock each, pistons are very light as well, all balanced, ARP everywhere for fasteners.
I have ran my car at the track(3500ft) and it ran a best of 7.83 at 93mph lifting at the MPH cones. Sorry but that's what you do in bracket racing when you take the stripe by 3 car lengths. Anyway, I know you don't like should be numbers but in my 4200 lb car that works out to 575 hp. I must also tell you that the car hit 4psi real fast and took until almost the finish line to hit 6psi. When I fed my numbers into the desktop dyno it said that the car should run low to mid 11's on a the measly boost that I am running in the quarter. My car ran very consistent until I decided to shift at 4500rpm instead of 4000rpm. It starts building boost almost instantly and is not peaky at all. I have ridden in marks car and it feels a lot like mine. His is on 8psi and mine is on 6psi. I think I know where you are coming from. It's kinda like "put this carb on or put this cam in and trust me you will gain 100 horse's" I have been there many times. All I can say is that mine works and marks 350 works as well as mine. I fully expect to see the 10's in my 4200 lb car on 12psi. I am one of marks first customers. I have had him fix the first turbo manifolds that I had a local shop build me that I will be running on my 67 lark. And I will be using one of his 350 kits in my 69 lark. Nothing says more than a repeat customer. I would say get your fuel curve correct and you won't be sorry. If you would like to talk in more detail the you can PM me your phone number and I will call you. I forgot to mention that this car ran 9.05's before 6psi and now 7.80's after 6psi thats 1 1/4 seconds. Good luck.
You all need to be running alky kit on these cars. It would help out tremendously! They two or three companies out there with great kits.
