John Scott

If your car doesn't pass then re-tune for emmission day. 8 degrees!! Get your timing up! Try 16 degrees and see what happens. You'll have to set your idle back down, and maybe take some advance out of the mechanical, but I bet it runs lots better. Colorado is experimenting with roving emmission vans. Set up on on ramps and other busy roads. Yes its the emmission police! Still experimental, but works like photo radar. If it "sees" a bad polluter it zaps the licence #. Bummer for some of the big cammed hotrods. Good for the air. I'm all for getting the oilburners and really gross polluters off the road. Most of us should have pretty effecient engines....WAIT A MINUTE! did I read that right. Your pulley size should be a 7 1/8" diam. for the water pump and 6 3/4" for the crankshaft pulley. Those are the standard sizes for the smallblock. Hmmm... JS [This message has been edited by John Scott (edited May 06, 2000).]

The guy I talked to liked the big bore short stroke design of the 377. He wanted to do something a little different for his camaro. His performance #s are pretty amazing for the weight of the vehicle. 11.1 @ 118. Aprox low 420s hp at Bandemiers 6000' altitude. Closer to 500 @ sea level. He's running a lot faster than some of his bigger cube camaro buddies. Maybe he just hit a good combination. I know he has Brodix heads, but they're untouched, as is. He knows he can bump the hp #s up but likes where it is as a street/strip car. I'm not knocking the other motors, I just thought it was an interesting set up. JS [This message has been edited by John Scott (edited May 06, 2000).]

From what I understood there are bearing spacers. Basically a bearing double stack! I would agree this sounds like odd design, but one friend of mine is in his 4th year of hard racing with no failures. In his case its a really fast reving engine with plenty enough torque to pull it through the 1/4 w/ a 2 speed. JS

Drax, good to hear your off to a positive start. Hope it all goes smoothly. Keep the progress reports coming. JS

Had a long talk with the local racers the other afternoon. After discussing the 383 and the 377 (400 w/ 350 crank), I was wondering why this isn't a more popular engine for the wheel spin happy Zs. The 383 is a superior torque motor, and gobs of hp, but w/ the light weight of the Z, wouldn't the 377 be a good choice? Its said to be very reliable. Every indy, exotic, competition engines, i.e. RACE, hot cycles etc have the over square design of the 377. Bigger bore/stroke. As I understand it the 377 allows more high end hp and the bigger bore is better for flame propagation, piston speeds. etc. At 6000 ft this combo. with some good heads and cam produce a high 10/ low 11 in a 3300 lb street driven car. Anyone consider this engine, or is it too obscure? [This message has been edited by John Scott (edited May 05, 2000).]

Since this occurred when you changed pumps... By all means check the float levels. The higher pressure might be raising the gas level before the needle/seat can shut the flow down. How are the needle/seat? Anything get in when changing the pump? Just a trickle should spill out of the sight plugs at idle. (fire extiguisher handy?). If you're getting a gusher out of the sight plugs and the float adjustment isn't helping, get the heavy duty needle seat/ assem. When your car hiccups or bogs, is it putting out black out the tailpipes, usually a too rich mixture transition from idle circuit to power, (my guess) or nothing, a too lean? Is 7 psi too high for idle? I'm not that familiar with the settings on the Blue pump. I've always run a regulator. Hope you find the trouble. (Probably see you over in the Fuel Delivery forum!) JS [This message has been edited by John Scott (edited May 05, 2000).]

CorZette: A mild cam, hotter than stock, can use a more agressive timing curve. Timing is never going to be the same for different engines. Without a run to a dyno or track, its going to be a trial and error approach. I'd shoot for about 12-16 initial (with the vacuum advance, if you're running it, disconnected when checking). If your balancer wheel isn't degreed up to 40 or so you'll have trouble getting the full advance #s down. Try raising the timing in 2 degree increments until you JUST notice detonation on the top end. DONT RUN IT THERE OR YOU'LL TRASH YOUR RINGS, PISTONS etc. Then back it of a couple. If you have access to a track, continue backing it off until performance decreases. You don't always make more power at the edge of detonation. (blower motors, for example, make more right at the edge, but its a risky game) With more initial advace its easier to adjust your idle/ and mixture circuit on the carb, too. Ideally you want to set your initial advance to an optimum level, good strong low end, not too hard to crank, AND your total mechan. advance usually in by 3000- 3500rpm. Put in more initial, sometimes you have to take out the total on the other end to keep it from pinging. Chevs. with around 9:1 comp. ratio like about 16 initial and 20-22 (read at the crank) more mechanical for a total of about 38 degrees. These are ball park figures. so try what seems to work. Listen carefully for detonation! Since stock distributers usually have too much advance built into them, get one of the spring/weight/limiter kits. Most come with fair instructions. Mallorys have set screws in the distrib. plate. My car idles great @ 700 rpm in gear due to my wide lobe sep. angle on my cam. In contrast my last big block was still sputtering @ nearly 2000 rpm in gear, and wouldn't really smooth out 'till 4000! 7-800 should be ok for a mild cam. JS [This message has been edited by John Scott (edited May 05, 2000).] [This message has been edited by John Scott (edited May 06, 2000).]

My wife and my first date was at the dragstrip, 18 years ago this July! She turned into a gearhead when we bought her first project car her senior year of highschool, a '68 cougar. Two cougars later, she could do a fair job of changing the lifters, adjust the rockers, and put up a good conversation what duration and lift were. She could even tell if a car was running a solid lifter cam by the way it sounded! When she went to college she checked out books, w/o my knowing, on internal cumbustion engines. No wonder she knew about hp and torque! She loved big cams and loud pipes. She was hell on tires too. Years later when our son was born everthing car-wise for her stopped. She took up her old passion of gardening. She gets a rose bush, I get a blower. Fair trade?? She gets(I build) a perrenial bed, I get new seats. See it works! You know that fountain and water garden? Did I hear T56?? (don't get me wrong, it's still THATDAMNCAR most of the time!) Kids will definitly change your outlook on life and prioritize your budget. You don't have to give up your car projects, but it does take LOTS longer to make additions/upgrades. I will never put my car above my family, but it is understood that it is an important part of being who I am. Put the $$ in your car while you can, (house payments, college ed. funds, remodels etc. are expensive!)THEN find someone who is understanding of your interests! JS

Myron, They make some cool plates for the smallblock/ v6. Thanks for the idea. See! Lots of solutions to put the 4.3 in the Z. Oh yeah, the V6 isn't recommended to have soild mounts. Some kind of damper or bushing would be necessary. John [This message has been edited by John Scott (edited May 09, 2000).]

Believe me, there's plenty of us out there that are survivng in our Z cars without much more than engine/transmission transplants. For those of you fortunate enough to have the money/ time/ and passion for the project, and I mean this sincerely, more power to you. If you are going to push it to the limit, top end racing or whatever, then yeah you need to be concerned with every detail and safty issue. Ditto if you need 450 hp. If you want a fast street car that can give you a lot of bang for a buck, then you can do that too, with out the high dollars. Some will shun a high powered Z with a original chassis, but come on, if you are running some decent hp in a light car, then living without risk isn't in your future. My .02 says build a car the best your wallet will let you. BTW I wouldn't trust a rusted out Z with a Yugo motor in it. A sound chassis can give plenty of good support for a street machine. Personally I don't think anyone can come up with a magic hp number that turns the Z unsafe. I think a large part of that will be who gets behind the wheel. Who did the wrenching? Who did the welding?. Did you remember to tighten your mounts? How about your lug nuts? If I had $100K to spend anywhere, it would go straight into my Z. I don't, but I've been enjoying the hell out of it for many years now with few complaints. Do your best with what you have, learn from it, improve it when you can and most of all, enjoy it! JS [This message has been edited by John Scott (edited May 04, 2000).] [This message has been edited by John Scott (edited May 04, 2000).]

One other thing to check. With the cap off, before it gets hot, can you see fluid moving through the radiator when the thermo. opens? Check for blockages. I had a really hot big block that had a slight compression leak into the coolant causing the fluid to foam, resulting in overheating. Also the advance thing works. Just don't overdo it. Also don't forget to then take out the unneeded timing at full advance or you'll be predetonating. Shoot for mid 40 degrees total in before 3000. The 20 initial seems high, but works for some of the bigger cams. I'd try at least 16+ to start with. Should perk up your low end too. If cranking is hard, a start retard is avail. from Summit. Different engine combinations like different timing curves. You'll need to experiment. Good luck! JS

Since I don't have the popular JTR mounting system in my ride, I'm wondering where the engine is placed height-wise in the chassis. Could some one measure from two given fixed points, say the top of the bellhousing, where it peaks in the middle the the top of the rain channel on the sheet metal directly above it, or top of steering rack to center of crank or water pump centlerline. Any fixed points. I'm curious how low the mounts place the engine. JS

A crossmember, probably would be the best solution for support and rigidity. JS

Drax, What is your definiton of cheap for an IC? Performance #s, $$. Just curious. They don't give the new ones away at ATI. JS [This message has been edited by John Scott (edited May 01, 2000).]

Tanks are bulky too.

Im going to use the ATI designed intercooler for the Procharger. They claim their two row will be more than enough for 4-500hp applications. They make a bigger 3 row, but claim it will be overkill. I think it is about as big as my radiator. About 24", 3" deep. When I get the clutter of my trans cooler out of the way it should fit pretty well. JS

Good point Pete, Yeah, I discussed that with a chassis builder who was building my mounts and crossmember. Front mount engines can put a lot of stress on the bell housing. Usually some additional support is recommended at the bell area. We figured, and hopefully we were correct, (so far so good) that the shorter v6 could get by with just the front mounts. They are in a similar location from the bellhousing forward as the v8. I'm going to try and post some pics of my mounting system to give a clear idea of what I've done. I really like being able to drop my oilpan, crank, and all w/o pulling the engine! JS [This message has been edited by John Scott (edited April 29, 2000).] [This message has been edited by John Scott (edited April 29, 2000).]

Yes the 4.3 and the smallblock v8 have the motor mounts in the same location, in reference to the FRONT of their engines. You could conceivably use the JTR kit which would achieve having the FRONT of the v6 exactly where the front of the v8 is placed. The problem is that the v6 is shorter by 1 cyl/bank so the transmission and all its mass come forward into the engine compartment. This would be a simple swap for it would allow access to the bellhousing bolts and great tunnel clearance, and you'd need a longer than my 19" driveshaft. BUT, you lose the great handling/balance potential of placing it against the firewall. Setting the engine as far back as I did placed the chevy mounts WAY behind the Datsun pad locations. My rear bias is slightly heavier in the rear, even more so than the V8 swap. The handling benifits will be superior with my or similar placement. JS [This message has been edited by John Scott (edited April 29, 2000).]

If you do go the carb. route, then the Procharger will be the best system. It's compact and simple to run. A streetable 6 really needs a power adder to be a good performer. JS

Thanks everyone for the replies and suggestions, Drax, no intercooler yet, but I just got the dimensions (they're big!) and pricing info last week. As I said earlier, I'm at the edge now for pump gas and need a buffer. I think I'll follow Ron's suggestion or go with a 50/50 mix. I built my engine with the intentions of driving it hard. My builder spent a lot of time making sure it could take lots of abuse. I should have opted for the 4 bolt back then, but I was convinced that I'd never see more than 10 psi. I don't plan on always pushing this much boost, but as easy as it is to swap drives for race days, I need to be doing some experimenting, and if I don't push it, I'll never know what it is cabable of. I thought I'd be happy with 8 psi 5 years ago! I'll always want more! The intercooler is suppossed to add another 10% hp at a few lb lower psi. and will definitely give me all the room to 20+ to play with. I won't run over 18 until I get the 4 bolt upgrade, about a $500 machine/parts bill. By then I can re-ring/ bearing, and give the insides another good look. Now, has anyone gone to a Dynojet or similar facility? JS [This message has been edited by John Scott (edited April 28, 2000).]

Thanks, Pete. I am familiar w/ the book and the placement of the jtr mounts. Still the motor mount similarities of the 4.3 and smallblock, in the JTR's mount position, would place the TRANSMISSION of the V6 swap closer to the front of the car by more than 4" than in the v8. The front of the engines will be in the same location. If you go from the back of the engine placement, mine is like the v/8 placement, then the mounts are out of reach of the Datsun pads. In fact, the Datsun mount pads are well in front of face of my engine. Finally got the JTR book for future reference. JS [This message has been edited by John Scott (edited April 28, 2000).] [This message has been edited by John Scott (edited April 28, 2000).]

I guess I should have given a little more info. The effective c.r. was given to me by Procharger as the max. allowable for THEIR system on pump gas with 7.5:1. 16 psi with 7.5:1 piston c.r. will give a "safe" effective ratio of 13.0. For example a 9.5:1 engine can only see 7 lbs. boost max. The lower the piston comp ratio the higher the effective. Thats why I went with the ultra low c.r. Intercooling is a much higher # for 7.5:1, 25+ psi ON PUMP GAS! Roots type blowers are well under these figures. I don't think ATI wants a bunch of lawsuits over their claims. At 16 psi, there is no detonation on premium fuel. I've pulled my engine apart on three different occassions while running the 14 psi, and other than when I was going through my tuning phase,(lots of abuse/ too much timing, lean jetting) everything looked great. Pistons/rings were fine, rod bearings showed a slight indication of detonation. Since then, I've got my tuning pretty well dialed in and I'm on 4+ years of pretty hard driving. Lately, with the boost change, and since I'm somewhat over their recommendations, I'm running 104 octane booster, until I can figure how much race gas/prem. to run. When I get it to the strip I don't want to be choking it down with over rich fuel. I know some people blend their fuel. Just trying to figure out how much to run to bump the octane #s a few notches. JS [This message has been edited by John Scott (edited April 27, 2000).]

I'm not aware of any kits for the v-6. I blocked up my V6 on 2x6s in the desired position, and designed my own. Motor mounts are pretty easy to fabricate and can be done at a welding shop for very little. I think Scottie-GNZ's mounting pads were welded to the frame rails under the 6's stock motor mount location or you can use the stock Datsun mount locations and Datsun motor mounts that bolt into the front of the engine, similar to the old 50s chevy, I think. If you or anyone wants some basic drawings of mine I can send them. (4.3 chev) Once you get the engine where you want it, the rest of the swap is like any other. JS [This message has been edited by John Scott (edited April 27, 2000).]

Drax, its what you do with it that counts. It would be a sin to leave it stock! Make it the baddest techno- Z motor on earth! GO FOR IT! JS [This message has been edited by John Scott (edited April 27, 2000).]

I talked the the folks at Motorsport and really like the rear deck lid spoiler they have. It is taller than the BRE style and they claim it will add some good downforce. They also claim it needs to be blended into the body or it looks like crap! I've seen so many 'glass attempts gone wrong, peeling, cracking, spiderwebbing of paint, etc. it scares me. Anyone have a fool proof method of permanently bonding this to my deck lid? I don't want any problems downt the road. Thanks! JS