Guest Anonymous Posted October 27, 2001 Share Posted October 27, 2001 I did the math, figured out all the parts I'll need (less a few miscelleneous pipe fittings I can get from the hardware store) and put together my budget. Provided that the camaro deal falls through, I'm going to build a v8 Z (or ZX) within my budget of 3500 dollars. The only hurdle is that in order to stay in my budget (everything other than this was price checked) I will have to either find a decent 280z for 700 dollars, or find a decent 280zx for 1000 dollars (ZX conversion is actually cheaper than Z because of some differences in the process of the conversion). The engine will be a 350 with the northernautoparts.com street performance kit (hyper pistons), new water pump, new plugs, thick Accel plug wires, K$N Air filter, new t-stat, Sportsman II heads, Summit Roller Rockers, Holly 600cfm carb, single plane weiand intake, and tall valve covers. Oh, and a hipo Accel HEI. The tranny will either be a muncie four speed or a th400 with shift kit and B&M shifter. I'll likely use the muncie so that the hydralics will be ready in case I decide to put in a t56 down the road (hope so! LOL!). A concern I have is the tires/wheels... will stock datsun work, or will I need wider ones? How much HP should that motor put out? What kind of quarter mile times should I expect? And how would it stack up to a 600 horsepower '79 camaro?? Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted October 27, 2001 Share Posted October 27, 2001 I'd think it would be in the 12's at least, probably low 12's, probably closer to the 11's thats where alot of the HybridZ's are at, probably be close with a 600 hp camaro, it weights probably 3000 pounds or more, but he probably has you by 150-175 hp. My guess (without the aid of Scotties Calcubobulator) is it would be pretty close, maybe the difference of reaction time. (purely speculation of course, YMMV) Stock tires will work, but to run a 600 hp camaro your going to need width which means either using a cut down 280z spring and raising the bottom spring mount, or using like a coil over kit to have the adjustment. This will clear the way for more tire, I think Scottie-GNZ ran some pretty serious tire on a cut down 280z springs as I recall. You didn't mention what cam so HP estimate is difficult at best. Also need to know the compression ratio etc. One built like that with the right cam would probably spin a pretty easy 400-425 hp maybe more depending on cam choice and compression ratio. Carb, I've changed my views lately I think to the camp that says SLIGHTLY bigger is better. I'd go with a 750cfm Holley since your using a open plenum manifold. Reason for my change of heart is a formula I saw that showed the 350 air requirements, and it was like 670cfm (slightly bigger than the 600's and 650's people run.). Jetted correctly, it'll work great and give you more top end for sure (depending on the cam of course), just a opinion/sugestion anyway. Regards, Lone [ October 27, 2001: Message edited by: lonehdrider ] Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted October 27, 2001 Share Posted October 27, 2001 Well, I id some figuring up, and if I get enough added money to my budget to buy the actual tranny, and get a 280zx for $600 (or a 280z for $475), and use stock rocker arms instead of roller rockers, I can put in a t56. Would this be a good idea? I like the idea of six gears and the gas mileage related with that... But will dropping the roller rockers be a bad idea??? Hmmmm... Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted October 28, 2001 Share Posted October 28, 2001 That would be 280ZX 2+2 springs. That mod is detailed in the JTR manual or at least in the ancient version I have. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted October 28, 2001 Share Posted October 28, 2001 For a budget swap of 3500.00 bucks, a T56 six speed will eat half of that before you turn around twice. Its a nice transmission, but hard on the budget. Regards, Lone Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted October 28, 2001 Share Posted October 28, 2001 Thanks Scottie, I didn't know they were 2+2 springs, but I think I remember seeing it in JTR's book as well, but didn't recall the specifics. You had what 275's in there or something? Regards, Lone Quote Link to comment Share on other sites More sharing options...
pparaska Posted October 28, 2001 Share Posted October 28, 2001 quote: Originally posted by lonehdrider: Carb, I've changed my views lately I think to the camp that says SLIGHTLY bigger is better. I'd go with a 750cfm Holley since your using a open plenum manifold. Lone, I agree, as long as you're going with a vacuum secondary carb, a 750 on a 350 works well. Heck, the primaries flow less than a Rochester 2 barrel! And the 3310 is a much nicer design than the smaller side hung float carbs, IMO. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted October 28, 2001 Share Posted October 28, 2001 Yeah, wish I had bought the 3310 instead of the 1850 600 I bought, hindsight I guess. The 1850 uses a metering plate instead of a secondary metering block and main jetc. Its ok, but not as flexible. I may convert it to a 4150 using holley's kit, its about under 100.00 to change it over to a secondary metering block (well the kit is like 30.00, but then you have to have the fuel bowl and a few other things). Oh well, if we all bought the right parts, there wouldn't be all those great used parts to buy huh? Regards, Lone Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted October 28, 2001 Share Posted October 28, 2001 If the Holley manual is to believed, it would take a 454 to fully open the vacuum secondaries of a 3310. The chart shows a 350 having a difficult time of this, in virtually any combination of compression, cam etc. After I reviewed this chart, I borrowed a 4779 750 cfm manual secondary carb and after two timed runs on the 3310, switched to the 4779. (I had previously jetted the 4779 in the shop to the same CO readings on the primary side.) The result was a 3/10ths faster E.T. average for the next three time trials. Most of the improvement was after the eighth mile mark. Three tenths may not sound like a lot, but it equates to approximately three car lengths improvement at the end of a 1/4 mile race. The 3310 was replaced that same day and run two more times to verify the result. The car slowed back down to the old E.T.'s I had previously spent many hours contouring the secondary opening of the 3310 with a quick change spring kit. (This after accidentally catching more than one diaphram assy with one or more of the vacuum pot screws and ruining them.) I weighed the needs of the car to perform at the track vs. the street and decided that essentially they were one and the same. If I wanted gas mileage I would simply have to keep my foot out of the secondaries. The trade off between the two carbs seems to defeat the purpose of making ones car the quickest it can be. Memories of the "ones that got away" aren't soon forgotten. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted October 29, 2001 Share Posted October 29, 2001 Allow me to clarify, I did not mean that the t56 would fit my budget, I meant that I could within the 3500 dollars get everything except the actual tranny (clutch, flywheel, ect) and then come up with the money for the tranny outside my budget. The reason my low budget would work at all is I already have a 71 350 (with only 40k on it too!) and a muncie four-speed! Hehe, well I'm definately going to be building a Z now. The camaro deal fell through. Oh well, I'll be better off with a Z anyway. Quote Link to comment Share on other sites More sharing options...
pparaska Posted October 29, 2001 Share Posted October 29, 2001 Kim, thanks for that info on vac vs mech. secondary 750 holley's. If you were 98% street, would you pick the vac secondary (3310) or the mechanical (4779)? I guess if you set the tip in for the mechanical at 3/4 pedal or more, and learned how to not tip into it unless you were at 5000+rpm, the 4779 would be fine on the street. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted October 29, 2001 Share Posted October 29, 2001 Pete, This year the car has been 100% street driven. The 1500 mile round trip to Shasta in July netted mileages of everything between 15.6 and 19.7 with 17.2 being the average. As you said, the tip in point is everything. I have always liked the instant gratification of explosive throttle response. The gear split of the turbo 350 allows for the car to be easing down the boulevard at 30 mph, but a stab of the throttle results in an instantaneous downshift to first gear and an rpm increase which gives a feeling like you just got rearended by a catapault. No clutch to depress, no shifter to shift, just immediate 400+ hp on tap. The governor holds first to 5800 and then lets second go at 6200 which is a feeling I have never grown tired of. The combination of gears and manual secondary make this car accelerate like few other street cars in our area. (Plus it doesn't look fast.) FYI: The 700R4 gear split would not let such a down shift to happen above 15 mph. Many times I found myself with the four barrel wide open, trying to pull away with the 1.67-1 something second gear of the 700R4. What a dog! I wish they made a 700 with T350 gear splits. The manual secondary carb also responds more quickly because of the extra kick of the secondary accelerator pump action. The other reason I take issue with so many vacuum secondary carbs is that you are stuck with Holley's estimation of your needed fuel curve in the secondary side due to a metering plate vs. a metering block. Holley is very stingy about metering block info which might prove useful in tailoring these plates for optimum performance. The flexibility of a the manual secondary Holley carbs is excellent IMO. Everything from custom tailoring of the accel pump volume vs. duration to predictable power valving (as opposed to colored springs of unknown vacuum depression in the Carter/Edelbrocks) and external float level adjustment to name just a few. EFI is smooth, but I miss the raw kick in the pants that a properly setup four barrel delivers when stepped on! If there is a better responding carb than this 4779 I haven't found it yet, but I am always looking. By the way, if anyone is having difficulties with the 4700 series secondary carbs wanting to fuel foul spark plugs under full throttle, I found out why. The PVRC (power valve restriction channel) in the metering blocks of the 4700's is WIDE open. (.120+ diameter holes times 2!. I built my own PVRC pilot jets and drilled them to .045 inch. The 1050 Dominators only have a .062 inch PVRC's and the 750's had .120+ right out of the box! When one realizes that the power valve circuit richness only needs to be increased by 30% at most over the cruise mixture, these PRVC channels increased fuel richness through the power valve some 400%! No wonder the plugs fouled and the oil after just a few passes could almost be used for fuel. Quote Link to comment Share on other sites More sharing options...
pparaska Posted October 29, 2001 Share Posted October 29, 2001 Kim thanks for that description/analysis. Kinda wish I had a mechanical 750 now. BTW, you can convert the 3310 to have a rear metering block with jets. But you still wouldn't have the accel. pump. Quote Link to comment Share on other sites More sharing options...
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