Can someone list some V8 conversion info for me?

[Guest Anonymous]

I really love the 70-73 240 Z car. I am a car retard and can't install anything myself. I was thinking of a 350 engine for my Z car but I was hoping to get some of your views and recommendations for this.

1.)For all necessary modifications to make this work with safety and reliability, how much will it cost?

2.)How much should I expect shops to charge for the installation?

3.)Are these engines new or are used fine?

4.)How long is engine life?

5.)Fuel injected or Carburetor?

6.)Where to buy engines?

Please help, I want to buy asap!

[Guest Anonymous]

Oh yeah i almost forgot. what kind of 0-60 times and 1/4 mi. times should I expect? Is there a manual i can study so that i can learn to mod my own car instead of paying someone to do it?

[Tim240z]

DPG,

Best thing to start with is to use the search function on this site to find more info.

I think that if you have a professional mechanic do it for you (unless he's a very good buddy) will make the conversion very expensive As for motors, that is completely a function of your wallet size. You can buy a crate motor from GM/Ford etc or Summit Racing and the like, or get a junkyard special and either rebuild/build it or just drop it in and go. The reliability question is a function of what you put into it. If everything is new or rebuilt, then the sky's the limit. If you get JY special and drop it in, it's kinda the luck of the draw.

You'll find a ton of info on this site and help from the guys here

Get the JTR manual, it is more than worth it, I promise. $35 odd bucks will pay for itself 100 times over. There's a link to the JTR site on the index page of this site in the left nav bar.

Good luck, and try to do it yourself....As it's been said here a hundred times, this isn't rocket science, just takes a little research and planning.

Tim

[Guest Anonymous]

Thanks for the reply but I still am clueless on this matter. Can I have an estimate of what generally a shop would charge me for this? I don't know if it means $2000 or $10,000. And what is recommended, buying a crate motor from like Summit or hit the junkyard?

[383 240z]

That depends on want you wan't the shop to do? Turn key or just set in the motor and trans. The local custom shop and car crafters near me charge $90-$145 per hour not flat rate per houre worked The best bet is a crate motor a decent 350 from GM can cost as little as$1200 for a 300hp setup that only needs a dizzy,carb and headers. It even comes with a warrenty the local wrecker can only offer you a old (carbs havent been around for quite some time) motor with no history and a 30 second 30 feet what ever comes first garantee. Keith

[Dan Juday]

IMHO

Do it yourself: $2000 min.

Pay a shop:$7000 min.

There are no maximums!

 

Others here will disagree, I'm sure. Some claim to have converted for $1000 or less. But I think I'm at least in the ballpark.

[Peternell]

First, like it was said before get the JTR (Jag tha Run) manual and go from there. Excluding the ultra high dollar conversions on this board, I've seen the numbers of $2K-$6k (running engine vs crate engine and everything new) throw out as the parts cost and some wrench wizards doing the conversion in a weekend. That's with a LOT of good planning to have all the parts in place when the swap starts. Weekend conversions gotta be 2 good people working 12 hours a day (beer breaks included) so thats 48 man hours - beer breaks and reduced productivity due to the beer breaks = about 45 minutes of actualy work. More like ? 20 shop hours @ ? $60 per = 1,200 bones. Am I close guys??

 

How FAST do you want to go is closer related to how MUCH are you wiling to spend. Based upon your initial statement the $ to speed connection will be much closer than for many others. I see by your a profile your a banker, so you got $ just falling out of your pockets, right? Well your shop and the speed shops my see it that way. Don't assume the most expensive parts are needed, if some is good more is not always better.

 

Daily driver type ZV8 's on this have times from low 14 (stock 305) to mid 11's (healthy 350's/383's some with NOS) Heck there's someone from Texas that runs high 9's w/NOS and drives it one the street. Seems to be alot of daily drivers that run mid 12's and see a good deal of freeway time.

 

Oh yet, whatever trans you get make sure it has overdrive!

[Guest Anonymous]

Thanks a lot for the info. So I still am confused though. What range of hp does a 350 ci engine have? I want a Z as a car that I will garage for 50 years so I want something special like 350 hp. Plus I need big tools if I need to make this work by myself. What would I need to buy and how much will these things cost?

[DavyZ]

Typically, 350's have 250 to 350 hp. However, 350 to 500 hp is not uncommon either. You can build a 1000 hp 350 if you have the mean$ to do so. 350 hp is easily reached in a 350 Chevy with only a few modifications, and you can buy such engines from any number of engine builders on the web, in car magazines, and in the Bay Area. A Chevy engine can easily for 100,000 miles with no problems, but you have to take care of it.

 

If you plan on doing this conversion yourself, you will save yourself (and others) a whole lot of time by buying the JTR manual--the book goes into detail about everything you have asked about and gives detailed instructions about what goes into a swap and what can be expected. Why do you want to pursue this? I'm not trying to be sarcastic or dissuade you from doing what you want, but there is a lot of work involved in a conversion and everything you tackle (or pay to have someone else to do) is custom--trouble shooting is part of the game and that means time and a certain amount of required expertise.

 

You may want to seriously consider buying a V8Z. At least you will get to drive the car firsthand and forego the expenses involved with buying a bunch of tools and possibly paying for someone else's labor.

 

As for tools needed if you do this yourself, I would consider this to be a minimum:

 

Engine hoist

Wrench sets

Socket sets and wrenches

5 pound hammer

Screwdrivers

Prybars

Breakerbar

Torque wrench

Caliper

Measuring tape

etc, etc, etc.

 

Also, you'll need parts too:

 

Engine, transmission, new exhaust system, JTR kit, radiator, fan, etc.

 

This is a major project, but it is not impossible. Please purchase the JTR book, read it several times, use the search function on this forum to look up subjects you have questions on, and read, read, read! Good luck with your project.

 

As for 0-60 times, with 350 hp, I would think that 5 to 6 seconds sounds about right, maybe less. The transmission makes a difference, as does tire size & compound, and gearing. The more powerful Z's on this board are running 0-60 times in 3 to 4 seconds. I'm sure that Z's running the quarter mile in the 10's or better are easily in the 2 second range. I guess it depends on what you want to get out of your car and how much money you have.

[Guest Anonymous]

Always good to see someone new getting in. I am doing a 72 with a 325Hp SBC and a fairly resto at the same time. I know quite a few hot-rod guys and when I talked to them about my ideas the one thing I heard over and over was what do you want to do with this car when its done and what does the car have to do for you!! At first it seemed like an obvious answer,GO LIKE HELL AND LOOK GOOD. Now I am getting close to hitting the road, I Know what they meant!! Do you want to drag race road race or rally cruise and look good handle with the best of them speed, handling, comfort ride the list can go on and on. The point is, a moderate do over can be made to do most things well, but, the more extreme you go in one, the more you will have to give in other areas.Give it some thought, what do you want the car to do, once you know that, alot of the other questions will be answered and the project will be a lot more enjoyable : Live long and GO like HELL!!!!!

[74_5.0L_Z]

I have a 1974 260Z with a stock Mustang 5.0L and T5 tranny. The car only runs 13.20s at 104 in the quarter. My times are slow compared to many of the more modified cars on this site. But, a 13.20 quarter mile equates to a 4.6 sec 0 to 60. This speaks volumes about the capabilities of the Z car with even a modest V8.

[Guest Anonymous]

Don't overlook the use of the Scarab style mounting for the engine instead of the JTR or the MSA kit. Use of either of these two methods requires cutting off the factory hood latch mechanism in order to use a rear mounted distributer as well as dictates a requisite dropping of the entire engine and transmission back and downward to effect trans to tunnel clearance. Even then you may have to take a "5 pound" hammer to the tunnel to make it fit.

It you do NOT want to lose ground clearance under the oil pan, mount the oil pan lower than the front crossmember, cut the latch off or massage the tunnel, seriously consider the Scarab style mounting point. The mounts are inexpensive and easily made from 2x2 inch thickwall square tubing. No cutting is required, accept to enlarge the OEM motor mounting hole in the suspension cross mount. Cost: under $10.00 including fasteners.

Mounting the engine with no back set of any kind will allow the reuse of the factory reinforced trans mounting area as well as allow you to change from say a 350 to a 700R4 without additional changes to exhaust and all other ancilliary connections from the chassis to the drivetrain.

There are a bunch of good ideas in the JTR book but I think anyone considering a conversion should look at all available options before deciding on a particular method of conversion.

AC and heater connections in some cars protrude further away from the firewall than the set back kits allow for clearance between the engine and these components. A decision should be made in advance as to whether you wish to retain these items. The heater tubes at the firewall exit directly behind the passenger side valve cover and connection to them is made much more difficult in the set back positions.

Weight shift gains by moving the engine rearward 3.5 inches (JTR) and 2.5 inches, (MSA) are negligible. The JTR book admits that the amount is probably no more than 50 pounds depending on how much aluminum componentry is used on the engine proper. Most early Z cars were approximately 2 percent heavy in the nose anyway and with the V-8 this percentage goes up only slightly regardless of engine position. Our gas tanks hold between zero and 125 pounds of fuel which is a constantly changing weight behind the rear axel. This discussion of weight shift versus engine mounting position just isn't that critical when all relevant variables are factored in. I have done all three types of kits in the last 15 years, and for all practical purposes I wouldn't want to have live on the difference in steering effort or handling between the various kits. They are all good in some ways, but not in others. All hot rodding is basically a study in compromises. You simply have to decide what kind of a result you want,where you want this car to play afterward and then target that type of installation.

I flattened the oil pan badly on a standard speed bump in a parking lot at very low speed, in the only JTR kit I have done. Pulling the motor a second time and replacing the pan for free was a lesson I will not soon forget. (It was a brand new TransDapt chrome oil pan)

I personally appreciate the simplicity and overall clearances that the Scarab or straight up mounting position allows for virtually all areas around the engine. A simple change of trans cooling lines can be a far more lengthy and difficult task with either of the set back positions, as well as the fact that header options are reduced if one wishes to use full length style headers.

I like the idea of being able to retain the larger harmonic balancer, full size flywheel, starter, as well as the manual fuel pump.

From front to back, no portion of the engine or trans (accept for part of a header tube) is any lower than the front suspension crossmember.

Hillclimb and autocross results I have seen and participated in, do not indicate any clear winner as far as one kit design having an advantage over any other. There are just too many variables to accurately compare them.

I have been noticing lately what the weight distribution is for some of the new muscle cars and I was surprised to see that a couple of the front engine rear drive cars are as much as 10 pecent heavy on the nose! For the average Z car, that would equate to @250 pounds over the front end. The best percentage difference I read about was the Corvette and it has a 2 percent diff.

The best to worst case scenario for weight shift between all kits is approx. 50 pounds, with the heaviest "shift" readings being 150# and the "lightest" being 100#. Factory stock my 1971 was apporximately 50# nose heavy to begin with.

With the use of many aluminum parts, the total difference in curb weight before and after conversion was less than 100 pounds total. (2355 vs. 2440)

For me the most important considerations were not the weight issues, but cost, ground clearance, ease of maintenance after the fact and the fact that I wanted to use Hookers full length Super comp header on a 350 platform of 400 plus HP.

The car has given a good showing of itself by making six final rounds and three wins in Pro class, as well as posting three back to back hillclimb victories and one new hill record over a two year period. The condition of Idaho's "wonderfully" maintained highways in the mountains around where I live factored into the ground clearance decision as well.

If you can, get a look at cars which are already converted using whatever kit, and make some measurements looking closely at the various areas and issues I mention here.

"Measure twice, cut once."

[Guest Anonymous]

How do I change gearing ratios to make it fats. I am looking more for a fast street car with a little drag in it. I guess maybe I should buy one instead of making one. How often does troubleshooting come up in these cars? What do I look for when I buy a V8Z and how much are they selling for as an estimate? Best place for finding one? You guys are the best!@

[Modern Motorsports Ltd]

"How do I change gearing ratios to make it fats. "

 

Add a donut holder on your console

Seriously though...do you have the JTR book on order? fine reading even if you never acquire a V8Z.

 

For improved acceleration you want to numerically increase your differential (rear end) gears. ie. changing from a 3.54 to a 3.9 will increase your rate of torque application and subsequent acceleration. HOWEVER, V8Z's have lots of torque already and I'd recomend to anyone building one to try their stock ratio first (unless you're building serious power and know all the ins/outs etc). Often traction is limited in your first 2-3 gears with a mild (ie. 300-350hp) V8 let alone one prepped more, so increased gearing is NOT typically needed.

 

To change your rear gears you only have to change out your differential for one of higher numerical gears. You'll often see hipo Z's reducing their rear gear ratios for greater range and topend as some are destined for truly high speed

 

If you have mechanical interests that you've never explored and have the hobby time it can be very satisfying to build your own ride. Noone to blame or compliment besides yourself. A truly unique feeling that's hard to explain. But nothing wrong with using your checkbook as your main tool either. We all have our fav. tools

[Guest Anonymous]

Niles Crankshaft service, in Nampa Idaho has a 1978 280Z V-8 for sale.

386 Chevy stroker 400 block, 350+ stroker crank

Phase 6 heads with full porting, etc. etc.

The owner of Niles Crankshaft is an old hot rodder from way back and does some very nice work. He has put hours of time into the engine as well as everything else in the car. The list of money no object parts in this car is impressive.

It isn't much to look at as he never painted it but it is a solid rust free chassis and turnkey at this time.

For what is in the car, and the fact that it was professionally built, the price is very reasonable.

It is not advertised, but I talked to him this week, and he said that it is for sale.

If interested Niles can be reached at:

(208) 465-0118.

Be advised this is a mid ten second car as it sits.

[BLKMGK]

I'd have to argue that building a JTR setup requires banging the trans tunnel - certainly not with my T56. Flywheel is as big as what the T56 requires and my starter is looking a bit portly as well although it's suppposed to be a "mini". I can't speak to the weight aspect though and would LOVE to see some corner weights of a Scarab setup car. Let's also remember that where the stick comes up in a Scarab based stick car is a decent amount FORWARD of where you might like it. With the JTR setback the stick is centered nearly perfectly

 

I will say this though - swapping in a V8 to a Z is pretty easy on the scale of automotive projects. I'm NOT a super-mechanic by ANY stretch and I did it using the JTR manual and some help here. I did nearly ALL of the work on my own using a built motor. Heck, I swung the motor over the fender and into the car by myself one late night. My only previious experience had been bolt-on stuff on my Mustang and pullingreinstalling that car's motor. This was as easy if not easier than doing that stuff but having an experienced friend around would be a good idea....

 

Edit: DUH, does NOT require much banging of th etunnel (smack!!)

 

[ October 12, 2001: Message edited by: BLKMGK ]

[Guest Anonymous]

Man! Now I want to do my own conversion. Is the manual easy enough for a five year old to do the conversion? What do i look for in a used V8 Z?

[labrat]

Well, i don't know if it's easy enough for a five year old, but if you know what all the parts are and what they do, then you shouldn't have too much trouble. At least you have everyone here to help you out if it gets too hairy!

[Guest Anonymous]

Five year old, umm, not unless he's a gifted engineer to be. It does require some automotive mechanic abilities. The more you have the less problems you have when one bracket doesn't want to fit or is just a little 'off' and you have to resort to cunning and rework.

 

The engine you use is up to your budget and what you want the car to do. Do you want a drag car? Or is it a street/strip or primarily a street car? All of these factors will tell you what you want basically. I have probably down on the low scale of V8Z HP at probably 250 and even at that low a number, the car isn't what I'd call a slug by any means.

 

What do you intend to do with the car, and perhaps we can make suggestions. Good luck with whatever it is you decide to build.

 

Regards,

 

Lone

[Guest Anonymous]

Speaking of corner weights, how many of you got a chance to see Dustin Rinehart's beautiful black 400 Chev powered 240 at Mt. Shasta this year?

In a field full of experienced drivers and outright race cars, Dustin took TTOD by almost half a second over the next closest anything. This year was a repeat of his performance of last year when he also set the top time of day.

For anyone who believes that corner weight is an indicator of handling you should know this. Dustin's 400 is mounted over 5 inches further forward than a JTR style mount. In all honesty I must admit that I have always tipped the handling question in favor of the JTR cars. I also read the book and with no imperical data to compare with, I too assumed that far better handling went hand in hand with equal weight balance front to rear.

Watching Dustin dominate a huge class of full on 510 autocross cars as well as Z's gave me pause to consider that my own success with my full forward mount (3.5 inches forward of JTR) car had not been a fluke.

Over the last several years, I have had a great time competing in numerous hillclimb events against a two driver JTR car which on paper should have left me in the dust. This vehicle is well prepared with cockpit adjustable braking and much more. Both of the JTR car's drivers have competed for many years in the car. We ran exactly the same tires and compounds, transmission configuration and rear end ratios. Yet in the only hillclimb that the JTR car has won, the margin of victory was only .062 of a second over my car. In the events which my Scarab car won, the margin of victory was measured in full seconds. The Scarab car set a new hill record at Teton Hill Climb in 1998. My brakes are and suspension are bone stock, while his is a well sorted 2+2 boostered, Toyota calipered set up.

I have read all the archives I could find on this board and I couldn't find good hard data regarding the actual corner weight differences between Scarab mounting position cars and the MSA and JTR cars.

As an engineer by vocation and training I question virtually everything and like to observe from real time results what works best.

Does anyone have any first hand data of corner weight versus handling results from either slow speed(autocross) or high speed (hill climb)events?

I know what the on paper indications are, but do these promises really actually make it to the pavement in V-8 Z conversions?

I am looking for solid performance data, not supposition or instinct. BLKMGK brings up a good point, I too would LOVE to see the corner weights differences between the cars.

From my first hand observations, the promise of far better handling in the JTR cars simply hasn't manifest itself in the various race venues I have watched and participated in.

I know that the discussion of weight balance is as old as the conversions themselves, but would anyone be willing to weigh their cars and perhaps post the results under a separate topic heading? I really would like to have several final weight results to ascertain the actual measured total weight gain or loss over the front axel between the various mounting points. A description of the actual componentry used in the conversions would be helpful as well.

Any one else interested in this beside me?

I have good reasons to ask, as I am in the middle of converting a 75 280 to a 4.3 and a T56 combination. I am concerned that the major loss of weight up front may actually result in a handling problem at high speed.

Any one got good data on this swap as well?

Thanks in advance.