Just aquired SBC ZCar! Newbie would enjoy thoughts on this c

[Guest jknust]

WOW.... I am glad I did some quick searching and found this forum... it is awesome! Even better, I just acquired a SBC 72 240Z and wanted to get some general thoughts about performance and value on this car (what a blast it is!!). I am a newbie when it comes to a SBC (although I have a great deal of experience with Z Cars), so I thought I might tap the resources of the HybridZ forum.

 

I posted details about the car here http://www.mazduh.com/default.asp#240z>http://www.mazduh.com/default.asp#240z (I am still going through receipts and digging up info and I am posting it there). If anyone likes... I can post the details here but thought my site would be easier.

 

My basic questions are (and I don't plan to use the NOS):

- What is the approximate HP/Torque of this motor?

- Where can I get "DeskTop Dyno" programs (and which is recommended)?

- Are the parts a good match? Is this motor "over-cammed" with .579 Lift and 324 Duration?

- I was told to shift at 6,800 by the previous owner (which this motor likes to rev to), how would you determine rpm limits and is this safe?

- What is a ballpark value of a car like this?

- Would this car be a better 1/8 or 1/4 mile car? What would be guestimated performance numbers with this setup for 1/8 and 1/4 mile?

- Some of the first things I plan to do are cage, racing seat and harness, more tire, different hood .... thoughts?

 

-¿oshua (one happy new HybridZ owner!)

 

BTW: This car sounds and looks mean and I get comments galore no matter where I drive it.... gotta love it!

 

[This message has been edited by jknust (edited March 27, 2001).]

[BLKMGK]

Okay - some comments

 

1) Hate the hood scoop but that's a personal thing.

 

2) Need you to please crawl under there and take MANY pics of the rearend setup and get LOT'S of details on how it was done. Pretty please!

 

3) You'll want to consider an overdrive tranny unless you don't hit the highway much. there are probably osme that would be VERY interested in knowing more about the clutch slave.

 

4) Motor is not in the JTR setback position. Weight distrobution will be a little "off" especially with iron heads. How does it drive? If the steering is really heavy this might be why. If it drives fine then it ain't broke I guess.

 

5) Would like to know what you've got for front brakes on that puppy. You may find you need more, drive it and see.

 

6) What radiator is that? How well does it cool?

 

Overall it looks damned nice! Knowing the previous owner is a big plus. That rear swap is one that I and others would be very interested in knowing more about too. More pics man, more pics. I'll host some of them if you need the space. Welcome aboard!

 

Oh, and I also like the red Base RX7. I've got a Base that was red and is now Ferrari Yellow Bunch of mods to it too. Nice to have yet another RX7 person on the board. We've briefly tossed around the idea of a 3rotor Z too! that would be an interesting ride to say the least.

[Guest Fast Frog]

jknust:

 

IMHO, it appears to me that your new acquistion is setup more for racing. Your compression ratio is a little hi for the street unless you've got some "knock" sensor like an MSD or other devise, or running 95-100 octane gas or additive. That's a lot of cam and a big carb for just street action, but once you've got some rpms on the clock-watch out!!!

 

P.S. You can get Desk Top Dyno 2000 from JEGS, and probably other auto supply warehouses. I've got Dyno 28 and 2000. Dyno 2000 is in a Microsoft Word format.

 

Have fun!!

 

[This message has been edited by Fast Frog (edited March 27, 2001).]

[Guest RON JONES]

Nice Car.I agree on the hood scoop,not my taste on a street car.Not to crazy about the wheels.Other than that I love it.I would also like to see some detailed pics of the rearend set up.And I know Myron wants to see those pics as well.

[Kevin Shasteen]

Your definately set up for racing & not for street. If all you're wanting is something to run at the strip then it sounds pretty rock solid w/M22 & the beefier rear end-(that all of wish we had).

 

I'm originally a 70 442 enthusiast so I kind of liked the hood/reminded me of the W-25 hood from Olds; still wish it were a little more "Low-Profile" & it would be perfect for the street as a sleeper as for now-the hood kind of gives you away/no sneaking up on poor unsuspecting victims! I liked the steering wheel as it reminded me of the Olds "Sport Steering Wheels" & was almost an identical match....liked that touch. Interior did look extremely clean/nice purchase!

 

What are the tire sizes; I know your site says 15's on the rims but what are the tire size dimensions? And yes/please please please obtain detailed pic's of the differential & axles!

 

Welcome to the site!

 

Kevin,

(Yes,Still an Inliner)

 

[This message has been edited by Kevin Shasteen (edited March 27, 2001).]

[Guest Anonymous]

Good looking car, yeah for me the prostock hood is a bit much, but thats a personal preference. Cam specs seem WAY to big for the street (usually 225 @ .050 is what I'd suggest for max street cam, but thats up to the individual and what they're willing to put up with). Also it would improve weight distribution to get the engine moved back to the 'JTR' position right against the firewall, several have made this conversion and from they're post doesn't sound to bad work wise.

Understand these are just observations, and I mean to take nothing away from the car or your excitement of it, just things that may improve it or at least make it a little better street car (for the strip, the engine is definately the business by the looks of things..).

 

Respectfully,

 

Lone

[MYRON]

I am guessing that motor to be in the 450hp range. My previous motor had close to the same cam and better flowing heads. If you could get good traction mid 7's in the 8th

mile and high 11's in the 1/4 mile. I like the other guys would really like to see more on the R230 conversion...

 

Myron

[fl327]

yo youve got a wild car there big guy!

wow! youve got the scarab position like mine, finally someone else with the far in front engine setup, i personally dont feel the understeer, but no roadracing yet...

that hoodscoop is loud, but i bet that car has the guts to justify it, i hope. show us the R230! please please show us...

man that thing is crazy looking man!

congrats

 

ps. smoke em up!

[DavyZ]

Very cool car you've just acquired! Yes, I echo the thoughts of the other guys that this car is set up primarily for racing--which is not bad, but won't be as fun running on the street for any extended period of time. If you plan to just race the car, keep it as it is since it looks VERY effective for what it is meant to do.

 

Things you may want to consider if you will use this car for things other than "just" racing at the track:

 

1) Upgrade your tranny to a T56 if possible--the revs you will have on the street will be so much lower, you'll save your engine and your ears!

 

2) You could also use the JTR setback mounts to better balance the car's weight distribution. The "Scarab position" which your car has is o.k., but is not really the best for overall derivability--fortunately it is easily and cheaply corrected with the proper set back plates.

 

3) The hood scoop is good for allowing the carb and high rise intake plenty of room, but might be difficult to see around in traffic. A cowl induction hood would allow room and still give you visibility.

 

Don't take any opinions from the forum personally, since each of our cars is a personal expression of taste. What is good for you isn't good for someone else and vice versa--that's ok--this is America!

 

If you dig into the archives, you'll find answers to many questions regarding hood scoops, wheels and tires, roll cages, etc, etc.

 

I wish my Z looked as good as yours! You have a great car and should be proud! But please, POST PICTURES OF THE REAR END ASSEMBLY!!!! Welcome to the forum and enjoy the ride!

 

David

[Guest jknust]

MANY THANKS for the responses.... I will be taking the car to a local shop this weekend that I used to work for (The Z Doctor)... and still have keys to. I will have it on one of the lifts and will get more pictures at that time of the differential setup and post them to my site (along with more pics of the radiator, brakes, clutch setup, fuel cell, etc.). This is of course weather permitting for shop use this weekend.... they are calling for showers this weekend and I am determined not to drive the car in the rain if at all possible.

 

Again, this looks like a kick butt forum and I am looking forward to tweaking the car over the coming warm months and posting and replying here. I greatly appreciate all of the comments and thoughts!

 

-¿oshua (I did one phat Burn-Out during lunch today!)

 

[This message has been edited by jknust (edited March 29, 2001).]

[BLKMGK]

Drooling over the prospect of getting a look at those diff pics. Th eR230s are supposed to be much easier to get, posi, and actually cheaper than the hard to find R200 LSD. The trick has been figuring out an economical way to get them mounted! Pics of your install would surely help. Any details that you can provide about the halfshafts and effort put into installing it would be great.

 

I'm also interested in the clutch setup and radiator. Have you driven the beast on the road much yet? Understand about the weather - yucky here righ tnow that's for sure!

[brnin8r]

Hi all - fast forward many years, and I only put about 1,500 miles on this car. I had to reregister, it lost my account (says I was a guest?). I'm getting back into this car, and will get all those pics of the setup. Stopped by the 75-80 drag strip Saturday - might have something to do with it (girlfriend was even fired up and turning wrenches with me).

 

Anyway, last year it developed a miss in #6 (second from the rear, on passenger side), and just now got around to start tearing into the motor. Turns out the #6 exhaust valve pushrod got boogered up, and is shorter than the rest (not bent, but mangled, like it was beaten on the top). Interested in thoughts on what might have caused it, and where I should look next )b/c of the high lift cam?)? Pics posted below, and you can see the exhaust valve is "cleaner" then the rest on that #6 cylinder, and piston on #6 seems OK - no evidence of valve strike. Rockers on #6 seem normal too - just some strike marks though where the shorter rod came out of the socket. I'll have to find my notes, but I think in the compression check there were no obvious problems (all within about 5-10% of one another).

 

Trying to decide how deep to go into this, (just freshen everything up, look at different head options, whether to throw these 492 heads back on, etc.).

 

 

 

 

 

[jt1]

Check the rocker carefully, it's hard to imagine the pushrod being that bad and not hurting the cup on the rocker.

 

The lash could have got loose and it just beat itself to death, it may not have been oiling, or you could have lost that lobe on the cam. Just have to check and see.

 

492's were the primo head of the day, but there are better offerings now. It depends on what kind of shape they're in, your goals, and your budget.

 

John

[BillZ260]

While you have it apart you might as well make any changes, if any, that you have been wanting to make. It's also an opportunity to check everything. Since you didn't build the motor, it will make you a lot more in-tune with your car.

[DavyZ]

Welcome back to the forum---at least you kept the car!!

 

If you wiped out the cam lobe as jt1 suggested, I'm sure you know to replace it Actually, if you don't have the cam specs and don't know exactly what you have in there, why not replace it anyway with something that you know will work very well with your combination of parts? It's just a suggestion. EDIT: you seem to have some of the specs, but what the heck, new parts coming to your door is like Christmas in July

 

I have seen bent push rods, but not a butchered one like yours. That is very ugly and would make me want to tear further into the motor...

 

Davy

Edited June 30, 2009 by DavyZ

[hoov100]

my guess's no oil, the lash was too tight, or the lifter failed which caused it to stick up?

[dr_hunt]

That is pretty common with higher spring pressures and what appears to be stock pushrods if it gets alittle loose. I've seen that pretty frequent on engines that don't really have all the right parts. Might check the studs on those heads you might have one pulling out. Some chrome moly hardened pushrods are in order. If those are stock then when you put it back together you should check the geometry and buy the appropriate length pushrod.

 

IMO the best combination would be a set of dart iron eagle heads in the 76 cc chamber size. Matched with those pistons you would be near 10:1 which with the right cam would be perfect. Then you get screw in studs, guide plates and some better flowing heads worth about 70 more HP than you have now!!

 

Those rocker arms are the lower end crane versions or appear to be. The cups on those are replaceable and are damn tough, but like someone mentioned, check them over.

 

If your spinning it to 6800 then you might invest in a set of eagle rods, have it all balanced and then put it all back together. Hydraulic cams available now spin 7000 with ease given the right valve train, springs and titanium retainers.

[240Z8_Dad]

Hi all - fast forward many years, and I only put about 1,500 miles on this car. I had to reregister, it lost my account (says I was a guest?). I'm getting back into this car, and will get all those pics of the setup. Stopped by the 75-80 drag strip Saturday - might have something to do with it (girlfriend was even fired up and turning wrenches with me).

 

Anyway, last year it developed a miss in #6 (second from the rear, on passenger side), and just now got around to start tearing into the motor. Turns out the #6 exhaust valve pushrod got boogered up, and is shorter than the rest (not bent, but mangled, like it was beaten on the top). Interested in thoughts on what might have caused it, and where I should look next )b/c of the high lift cam?)? Pics posted below, and you can see the exhaust valve is "cleaner" then the rest on that #6 cylinder, and piston on #6 seems OK - no evidence of valve strike. Rockers on #6 seem normal too - just some strike marks though where the shorter rod came out of the socket. I'll have to find my notes, but I think in the compression check there were no obvious problems (all within about 5-10% of one another).

 

Trying to decide how deep to go into this, (just freshen everything up, look at different head options, whether to throw these 492 heads back on, etc.).

 

 

 

 

 

 

Any reason on the thread hijack?? :hijack:Please start a new thread, Mods, you agree??

[brnin8r]

Any reason on the thread hijack?? :hijack:Please start a new thread, Mods, you agree??

 

I guess I don't follow, it was an update to this thread getting thoughts on this car:

- I'm the OP (I'm the same person - forum dropped my account, I guess b/c it was so old, so I reregistered)

- It's the same car

- It's the same general concept (learning more about the car I acquired, getting thoughts about it from members)

 

I thought by posting in the same thread it would easily show the history and background of the car. The only thing that is off is the long timeframe. I looked at forum rules, and don't see anything about that and how is it I hijack my own thread? Curious.

[brnin8r]

All - I appreciate the advice and comments. Motor and trans are out, and I am thinking what to change. One thing for sure, the shifter on the M22 (always hit my hand against dash grabbing third). I think my goals for the car are a weekend/test & tune drag car. 1/4 mile strip (75-80 drag strip) is 10 miles from here, and I want to drive to and from, but have some fun there. On a nice day, might take the car to work (about 5 miles away) - but will not be a daily driver by any means. So I guess I'm looking for a budget track car, but enough street drivability to get to and from the drag strip. I'd be really really happy in the low 10's or high 9's (but realize it may take awhile and more $ to get there).

 

jt1 - thanks. I'll get a closeup pic of that specific rocker.

 

BillZ260 - thanks. Good advice, got me thinking I should go further still.

 

DavyZ - thanks. Supposedly this is the cam in there: Competition Cams 12-615-5 (314B-8) SOLID 314-1 324-1 276 286 .557 .578 108° (http://www.compcams.com/products/212-225.pdf). But who knows (will look for markings).

 

hoov100 - thanks. Will be checking lifters soon.

 

dr_hunt - thanks, very informative. Will check studs. What pushrods do you recommend? Looking at the pistons stamped with L2304 030 seems like they are TRW Forged (not the "Keith Black Forged" I was told verbally?). With those Dart Heads, those pistons, what cam do you recommend? If I'm going to buy new heads, should I maybe try to go aluminum, and lose a little weight (or is $$ way up there then for a comparable head)? I appreciate your input!