[logan1]

Ok so i have the following motor in my car right now:

The motor is installed in a 1970 Datsun 240Z

freshly rebuild Chevy 5.7L SBC 350.
4-Bolt main
Block has been bored 40 over
882 heads
Edelbrock RPM airgap intake
Holley 600cfm carb
New Comp 268 cam kit.
New flat top pistons providing a 9.5:1 compression ratio
M/T valve covers
New Black Coated Steet Rod Hugger Headers


I have the opportunity to buy a set of Patriot 23 degree heads for around $500.

Is it a good deal for these heads and should i buy them?
Will it provide me with a nice boost in performance?
Will i need to change my cam?
Will i need to upgrade my carb?

[cobalt327]

What is the port volume and valve sizes? If they're 185 cc and 2.02" intakes, it would be a decent match and will give a nice improvement. The 225cc ports and bigger intake valve wouldn't be a good match.

The cam and carb will work w/the smaller version. Long tube headers would be better.

[F-BIRD'88]

Any head change is a step up from a 882 head.

A cheap cylinder head is a cheap cylinder head. @ $500 for a alftermarket cylinder head (new?/Used?/used up?)
you will get about what you pay for and should expect no more.
New Patriots cost more than this....

And good cylinder heads are never sold off cheap.

A 600cfm carb is a restriction on any engine that makes more than about 350-360hp.

Cam....depends.... Its all in the details. A block hugger style short tube header is a power limiter.
The cam and exhaust system have to work together.

re: 882 heads....I have felt your pain... The best 882 cylinder head is a melted down 882 cylinder head.
great for hand porting skill practice thou.

[logan1]

I've sent the seller a few questions based on ur responses. Hopefully i get some answers soon. And i realize that you get what you pay for but like you said I can only upgrade from a set of 882's. Also I'm not sure but i figured that my current motor setup would make about 300hp at the flywheel.

[vinniekq2]

If the castings of these heads are still good,expect to do a valve grind,resurface and replace all the valve springs.There is a possibility that you may need a couple valves,and guides.Add all this in and consider new heads?Even new heads I would buy as bare castings then add or upgrade the quality of the valves and use the springs that the cam maker recommends

[cobalt327]

Originally Posted by logan1

I've sent the seller a few questions based on ur responses. Hopefully i get some answers soon. And i realize that you get what you pay for but like you said I can only upgrade from a set of 882's. Also I'm not sure but i figured that my current motor setup would make about 300hp at the flywheel.

If you and the heads aren't in the same place at the same time, beware of buying anything as expensive and as easily screwed up as a set of cylinder heads, sight unseen. You need to be able to fully inspect them, or have a machine shop do it if you're unsure.

[F-BIRD'88]

A great deal. Summit Racing Street & Strip® Cylinder Heads for Small Chevy SUM-162111 - SummitRacing.com

[logan1]

Originally Posted by F-BIRD'88

A great deal. Summit Racing Street & Strip® Cylinder Heads for Small Chevy SUM-162111 - SummitRacing.com

Well that makes the decision real easy. Guess im buying a new set of heads from summit. It'll probably be cheaper in the long run anyway.

[F-BIRD'88]

Its going to be like hitting the afterburner compared to the 882 heads.

[ap72]

Originally Posted by logan1

Well that makes the decision real easy. Guess im buying a new set of heads from summit. It'll probably be cheaper in the long run anyway.

Not that those are bad heads but shop around, there are a lot of options around a grand. BTW, I'm doing a sbc swap into a 280z, 302 sbc, t5 trans. any tips or insight? What did you do for mounts? I'm wanting to set mine as back as far as possible (no distributor).

[hcompton]

Are they used or new? New that is an ok price but used that is too much.

You can buy nice built procomp heads for around 600 a set new and bolt on ready. I think your heads now are too small and really need an upgrade. I would go bigger than 185cc intakes. 195 would be a better choice. I have pictures of the procomps i just purchased in my profile. They look nice. I was also told patriot are the same casting but truly not sure if that is the case.

Brodix dart wop and edelbrock all make a nice head around a grand all are pretty good in there own right. They will also make a nice improvement over the 882 even cut they are only ok. Unported it will be a major upgrade. One you will feel no matter what good flowing head you put on the motor.

268 cam is not that big but is not really tiny either with the air gap and long tube in a light car it should run good.

[techinspector1]

With 64cc chambers and 200cc intake runners, you'll be in a whole new operating range resulting from the increased static compression ratio of 10.2:1 and the need for increased revs to take advantage of the larger runners.

Always counsel with the tech at your favorite cam grinder for the proper cam to complement your combination of parts, but I'll get you started in the right direction with a suggestion......
If automatic, a 3000+ converter will be required. If manual trans, good to go. Either way, use a 750 double pumper and 4-something gears.
Assuming a flat tappet hydraulic camshaft.......
Crane Z-286-2
Lifters, Crane 99277-16
Fair idle, performance usage, good midrange HP, 3800-4200 cruise RPM, 10.25 to 12.0 compression ratio
advised.
Operating range 3000-6800 rpm's
Camshaft part number 113541/113542
Spring and retainer kit part number 11310-1
Duration @0.050 236/244
Duration @ advertised 286/294
Lobe separation angle 110
Intake opens 13 BTDC @0.050"
Intake closes 43 ABDC @0.050"
Exhaust opens 57 BBDC @0.050"
Exhaust closes 7 ATDC @0.050"
Intake lift 0.491"
Exhaust lift 0.497"
Here's the cam and lifters on Amazon.....

Amazon

Amazon

Installing the cam straight up, dynamic compression ratio will be 8.55:1. Good to go on pump gas.

Use these tips to insure longevity with a flat tappet camshaft.......
http://www.crankshaftcoalition.com/w...ips_and_tricks

Strongly suggest that you throw those shorty headers over the fence and install a set of 1 5/8" equal-length long-tube headers, with an X or H pipe before the mufflers.

[ap72]

Originally Posted by techinspector1

Strongly suggest that you throw those shorty headers over the fence and install a set of 1 5/8" equal-length long-tube headers, with an X or H pipe before the mufflers.

I'm guessing he's using shorty headers with a single 3-4" exhaust, at least that's about the only affordable option I see on a 280z.

[techinspector1]

Originally Posted by ap72

I'm guessing he's using shorty headers with a single 3-4" exhaust, at least that's about the only affordable option I see on a 280z.

Not if you own a Sawzall!!!!
One of the guys on the Datsun forum suggested that these will work....
http://www.speedwaymotors.com/Garage...SBC,54467.html

[logan1]

Originally Posted by ap72

Not that those are bad heads but shop around, there are a lot of options around a grand. BTW, I'm doing a sbc swap into a 280z, 302 sbc, t5 trans. any tips or insight? What did you do for mounts? I'm wanting to set mine as back as far as possible (no distributor).

Why do a 305sbc when you can get a 350 or a 383? DO you mean 302SBF?

The JTR engine mount kits a really good for the money and they will make the T5 shifter line up with the hole in the transmission tunnel (lil modification required). Also with the JTR kits you end up something line a 52/48 weight distribution with is excellent. You dont really need to go through the trouble of remote locating you distributor.