John Scott

If anyone is considering a centrif. supercharger thats going to blow over 14 psi, definitely go with the 10 or 12 rib design from the start. Ever since I bumped up my boost with the 8 rib I can't get enough belt traction. ATI claimed my 2.75" pulley was borderline with the 8 rib. Tightening the belt to the snapping point is only giving me short belt life and at $27 a pop, its not worth it! The 12 rib offers 50% more traction than the 8 and you won't need to run as much tension. There are ways to brace the compressor for less slippage, but the smaller pulleys just don't have enough surface area. The cogged belts are really pricey and pretty much race only. Just getting into a good 16 17 psi pull and having it slip back to 10 is worse than a cold shower! JS [This message has been edited by John Scott (edited June 10, 2000).]

Rob I wouldn't mess up my jetting over a cold start issue. It would be over rich the rest of the time. Most of my projects have had choke-less carbs. A few minutes at idle and it will be on its way. I know your Z is snug in the garage in the winter...isn't it? Holley's regular carbs still come with chokes, even if they are manual. No rocket science, but they work. You could always save your elect. choked carb for the winter months....Or add a supercharger! They'll start year 'round! JS

Rob, Have you looked at the new 4150 PRO series Holleys? I know this isn't the answer, but if you want to try my 600 Dbl. Pmpr. for a weekend you'd be welcome. It wouldn't be that big of a deal to "pop it off". The jetting should be close for our altitude and you could see if the float bowl position makes a diff. Two hitches: My center stud is a littler larger than original. I didn't like it when mine blew out @ 7000 grand and smacked my hood! OW! Also has dual fuel inlets. You'll need a y fitting or dual fuel line. Let me know. JS

A really boneheaded simple way of determining your compression stroke for #1: Hold your thumb over the spark plug hole (or just loosen the plug slightly. Turn the engine over by hand. As it comes up to TDC you will hear air escaping past your thumb. Thats your compression stroke! BTW I don't feel timing tabs are hugely useful. They are only a reference point to start from. JS

Just a guess...did you get a 305? The stock bore of a 350 is 4 inches JS [This message has been edited by John Scott (edited June 07, 2000).]

I don't think you'll be sacrificing any accel. for milage. You just get a bonus gear of 5th for cruising. (5 and 6th for the T56). JS

A last shot in the dark. Kenne Bell makes a cockpit controlled pump voltage stabilizer. Says it will keep pump voltage within 1%, eliminates fule pressure drop off, adjustable between 1-50%. Never heard of the thing 'till I ran across it in a turbo mag. 909 941 0985 (tech) JS

FastFrog Thanks for Rons #s. I'll be in touch with him. Not that familiar with TBI. I hope it allows big #s. JS

Rick, Thanks for the boat load of info. I like answers like that! I have a lot to learn. We'll be in touch on this one. The Sy/Ty guys have been telling me to get with the program and go computerized FI. I always research way ahead of my bank account, but as with the countless other files of good info I get off this site, it will be put in the "GOTTA HAVE IT" box. Two more questions. 1)Is ther a way to hook up the knock sensor? The few times mine has protested, (years ago when I was tuning) Its been noticible. With more boost, by the time I hear it it could be too late. 2) When you talk about the MAP sensor and ECU, is a 3 bar part of the Accel system? I will definitly be running more than 15 psi boost. JS [This message has been edited by John Scott (edited June 05, 2000).]

Scott, found a guy who builds a custom chip for the turbo. Still shy of the 18 psi though. JS

. With an intercooler you could have a very drivable 800+ hp smallblock. ATI pushes that idea around. No, this isn't about the # of cylinders, but the application of power. From what I've researched, of the street projects currently posted, the GN has the hp potential. Ffrog: More intercooled boost? YIKES! ZD: just waiting on a couple of more parts, lightweight flywheel, clutch etc. JS [This message has been edited by John Scott (edited June 05, 2000).]

Good points Fast frog, and probably a matter of pref. how you like your power served. You will have a broader torque spread. We have a local 383 vortech pulling some impressive times. (Low 11s 3300 lb car Bandemier). My point is that I'm seeing 10s, and 9s out of 262 ci and smaller pulling 3500 lb cars. What would this equate to in a 2500 lb chassis?. These are engines that can be driven home after race day. Yes you would have to set the boost back down and street wars are limited to your octane levels. Yes their crutch is octane. If this were applied to a V8 it would be phenomenal. Turbo boost is more evenly distributed throughout the rpm range than our linear supercharged boost. I can't hit 8/10/14 psi off the line. Its more like 2 or 3. BTW 16 psi is attainible w/o octane boosters and intercoolers. Its dependent on the adiabatic effeciency of the system. I've run 14psi for years and recently decided 16 is safe for my system. I think the 18 was pushing it a bit. Now I just shift a little sooner. High boost readings don't necessarily mean the engine is seeing more fuel/air. Sometimes its just stacking up in the manifold or the mixture expanding from all the induced heat. I think turbo tech has come a long ways and we'll be seeing more record setting engines using this combo. I've never seen a blower wind up a 1.5 litre to 1000hp. I love my Procharger. I think more HP can be made with turbos. JS [This message has been edited by John Scott (edited June 04, 2000).]

Scottie, Glad to see your out thrashing it. First round runs are pretty misleading. One of our local street "heros" ran a 14 sec. with his supercharged Vette on his first outing. Everyone smurked. He has the same set up, but dialed in now. Runs low 11s high 10s all day. Drives it to work year 'round. BTW I hear some of those Sy/Ty guys getting 14psi or so off the line. Awesome 60' times! JS

John, my carb is a temperamental SOB, too. Sounds like you had a lean stumble going into WOT. The richer accel. pump shot must have helped. I don't think you are masking a fuel line problem. I believe the stock lines can handle quie a bit of hp with enough pump. A big healthy 383 like some are running will of course need some garden hose size lines. A high RPM TOP END miss under load/ predetonation/ loss of power would be more indicative of fuel starvation. Low end stumbles, transitions to WOT, surging under cruise, stopping/ cornering etc are more carb tuning problems. You need to keep 4-5 lb at the carb at all rpms. Maybe even higher with smaller lines. (Mine runs about 4.5 to 5 lb at idle and kicks up to 14+ under boost.) Higher pump pressures make it idle rough, sloppy off line, because of fuel bypassing the needle/ seat. A good pump and regulator should keep up with a mild small block. It seems you could spend hours if not days finding the right combination. Good luck! JS [This message has been edited by John Scott (edited June 04, 2000).]

Any one else been feeling prehistoric with their carbureted engine? Even plain old FI seems mundane. I know they do the job, and can run really well, but after spending a few hours reading about the turbo technology out there, visiting the turbo websites, all I can say is its humbling. Knowing ther are only two american made turbo engines worth mentioning, that really can put out the power, (Syclone, Grand National) I honestly think for a street driven car, the project with the most hp potential is/will be Scottie's GNZ. I've read the engine "recipes" for 6-700 hp turbo'd 4.3s (700 they claim is the limit on a stock block and crank) and the @#$% Buick can make even MORE! These are ultra high boost, 27+ psi, engines that can still be driven around like mom's car when they're not rolling up the pavement. You can't put that kind of HP in a naturally aspirated V8 w/o big cams, high comp, etc. Listen to the 700 hp GN idling at the staging lights next to the 10 sec V8 it's about to beat, and you'll see my point. The biggest shortcoming of the 4.3 is its computer system whereas the buick upgrades seem to have no limitations. If anyone can apply this to a V8 you'd be pushing F1 like #s, and still be able to drive cross country. The new ceramic bearing fast spool up turbos make turbo lag a thing of the past. HP is a twist of the waste gate knob. If I had the $$, knowledge, there would be no question. I'd have the baddest turbo'd 1000 hp car on the planet. JS [This message has been edited by John Scott (edited June 04, 2000).]

One or both of you migh give me some advice here. Being computerized FI illiterate: Rick, how does your after market FI system work with the supercharged boost? How much freedom do you have with the fuel curves. Lets say driving from 4000 to 13000ft altitude, will it sense the change and adjust accordingly? I'm playing w/ the idea of the Syclone double batch FI system It has the L98 corvette throttle body. Wondering if it could be run from an aftermarket system like yours?? Scott, do you know if the Sy/Ty injection system can be run from aftermarket computer systems? Stock system upgrades for high 18+ psi boosts? Thanks! [This message has been edited by John Scott (edited June 05, 2000).]

Looking a little ahead here, but what should I shoot for when adjusting the clutch pedal freeplay. I've never had a clutch in the car before and have nothing to go from. Ditto with the slave pushrod. I'll be using the T5 bellhousing and slave. Thanks JS

N.W.M.S...... your olds info is commendable...(John remember F is for fast, later letter, better head,..got it) and I used to play with these. Too many years ago! Did you or do you run the beasts? I remember how my cheapie engine stand would bend under the massive weight. My fist engine rebuild, back in '76, a guy named "Shorty" a dark man with a little beret, about 5' by 5', lifted my block (a 400) out of my mom's T-bird trunk! JS [This message has been edited by John Scott (edited June 03, 2000).]

I honestly can't remember which heads were the most desirable, but I thought A/Bs. in a LARGE letter cast into the head. Joe Mondello, now probably run by his son, Bernard(I think) would know. There phone #s are still listed in perf. magazines. In any event, there cool engines that make lots of power at relatively low RPMs. Never seen guide plates on an Olds. Just the wierd trunion rocker mounts. JS JS

Myron, what is the casting letter on the heads on the 455? A, B, C,...? [This message has been edited by John Scott (edited June 01, 2000).]

Mike, adapter plate should be coming any day now. No charge. You can by me a beer someday! Seen plenty of 10 and 11 second Olds in full bodied Cutlass/F85s/442s...at 6000ft. The best "stock" engine I ever had was the 425 ci out of a 67(?) Toronado. BIG lifters bores allowed killer camshafts. My main gripe was they were expensive to build and hated high RPMs. Funky trunion rockers with adjustable pushrods! Remember the 70 W30s? Knew a guy who put a stock 455 in a camaro and ran low 12s @ 6000ft. JS [This message has been edited by John Scott (edited June 01, 2000).]

Go with a ratched one for sure. The 700's detents are small and easy to overshoot with the cheapie shifters...like I have. Nothin' wrong with autos. Some prefer them. I raced them for years in my 442 Olds. Hard to beat the consistancy. I'll always have one in my 24k/year truck. JS

Sure sounds like a fuel sloshing problem. Rob was experiencing a similar problem at his last autoX. He runs a holley, and is going to try different floats, (center hung). Maybe another member is running the Edlebrock carb. and has a cure. If not, I'd give Edelbrock tech line a call and see if they have a remedy for you. JS

Fast Frog, You've been a hard core standard trans man for ever, haven't you? The autos are all in one piece, i.e. case, bellhousing cast in one. The first gear ratio in the 700 with 3.54s is like running a 4.30 rear with a turbo 400. Its a short trip to 2nd. If a 5.0 mustang can go 150mph, less hp higher weight, and assuming you have the aerodynamics to try it, it should be easy. JS

3.06, 1.62, 1.00, .70. .....if my math is correct, 150 mph would take only 5000 rpm with 3.54s. (what gears are you planning on running?) You'll be shifting out of third 6500rpm @ 136 mph. ( a little less accounting for slippage. None when locked up in fourth) JS