Have any of you guys ran one before? I am refering to the 69 Z style. My father is contemplating buying one and putting it on his 69 Z but he has never fooled with them before. Any help would be appreciated, thanks. :bowtie:

I've never had the pleasure of driving one, but the original road tests of the 68 and 69 Camaros equipped with them indicated that they pretty much killed all low end performance on the little 302. If you didn't mind having the engine idling at 2000rpm and were willing to dump the clutch everytime you started out at 4000rpms, they were fantastic up to 10,000rpms.
If that don't make you smile, you ain't human.:p

His car is still set up from its street racing days so it curently idles at 1200rpm lol

a cross ram is just a layed over tunnel ram !!:) and be prepared to spend lot's of coin in purchasing one

Im not concerned weather its original GM or not. I've seen some Offy's and Eddy's go for 600-700 so not too too bad. Just got to buy 2 new carbs. but the end result is worth is:happy:

I talked to a guy who had one his 69Z car at a car show a few years ago,I second that Gary said it was a monster from 4500-8000 and needed to stay there in those rpm ranges,he HAD to run 110 grade fuel always during driving.

Full setups go big $$ - All original GM parts setups go over $20k, intake to air cleaner.

I'd say go for it, already kinda realizing what your in for. Just looked on Ebay and a couple of Offy's/Edelbrocks available... Seem to go for about 300 - 400 used (non orig. GM). There's a new Offy with linkage with a buy it now of 650. If you can wait till Carlisle I know of one guy who has them on a regular basis. Another place is racer's flea markets.

I have one on my '69Z...I use the stock compression, with GM off road cam (140 cam), Stahl headers . I run pump gas in it with out difficulty. It really wake s the 302 up. plus it looks cool. I ran the car with t eh stock 4 bbl, intake and cast iron exhaust (with the 140 cam in it then too) for almost 20 years before I switched to the crossram .http://members.cox.net/flowjoe/Z28/z282.jpg

Offy intakes are readily available through most parts houses...don't get sucked into the Ebay pricing gouge for those things... cosmetically they are the closest to GM...they have different linkage though. these guys http://www.pawinc.com/ used to have the best price on the crossram intake from Offy.

Here's Offy's catalog: http://www.exeterautosupply.com/Docs/Offenhauser%20catalog.pdf see page 26

summit sells the base for $343.39 http://store.summitracing.com/egnsearch.asp?Ntt=5893&x=0&y=0&searchinresults=false&Ntk=KeywordSearch&DDS=1&N=700+400429+115

and the top for $149 http://store.summitracing.com/egnsearch.asp?Ntt=5903&N=700+115+400429&Ntk=KeywordSearch

Here's a short video of a 69 like Flojoe's from one of the Gateway Camaro Club members at the Super Car Reunion,but with cowl induction.

http://i35.photobucket.com/albums/d160/62f79/th_acrossram.jpg (http://s35.photobucket.com/albums/d160/62f79/?action=view&current=acrossram.flv)

Here's a short video of a 69 like Flojoe's from one of the Gateway Camaro Club members at the Super Car Reunion,but with cowl induction.

http://i35.photobucket.com/albums/d160/62f79/th_acrossram.jpg (http://s35.photobucket.com/albums/d160/62f79/?action=view&current=acrossram.flv)
That's funny...it's yellow also!

That's funny...it's yellow also!


Looks like you have a twin in Missouri.

Here's Offy's catalog: http://www.exeterautosupply.com/Docs/Offenhauser%20catalog.pdf see page 26

summit sells the base for $343.39 http://store.summitracing.com/egnsearch.asp?Ntt=5893&x=0&y=0&searchinresults=false&Ntk=KeywordSearch&DDS=1&N=700+400429+115

Interesting combonations available. I like the Triple Webers

Contrary to what most people think, the GM and Offy style crossrams can actually work quite well at lower rpm without sacrificing everything up top. The 2 most important items in making these crossrams work are the carbs and cam timing. As far as the carbs go, the factory GM 4295 carbs are pretty much perfect out of the box--as they should be, since GM designed them for this intake.

Last year I built a crossram 302 for one of my customers. (it's covered in detail on my website, with a video of a dyno run at the end should anyone care to peruse) The engine was built completely to factory specifications save for SRP pistons, a set of Scat rods, and a cam that I don't care to discuss for several reasons. On a very conservative dyno with absolutely no tuning whatsoever, it cranked out 377 HP @ 6000 rpm and made over 300 ft.lbs of torque from 3000 to 6500 rpm on the very first power pull, with a peak of 355 ft.lbs at 4500 rpm. FWIW, at 4000 rpm it was making 352 ft.lbs, and at 5000 it was making 352 ft.lbs. (How's that for a "torque curve"???..more like a torque plateau if you ask me)

It's all in the overall combination. Don't look for one component to be the "magic bullet".
Eric

Contrary to what most people think, the GM and Offy style crossrams can actually work quite well at lower rpm without sacrificing everything up top. The 2 most important items in making these crossrams work are the carbs and cam timing. As far as the carbs go, the factory GM 4295 carbs are pretty much perfect out of the box--as they should be, since GM designed them for this intake.

Last year I built a crossram 302 for one of my customers. (it's covered in detail on my website, with a video of a dyno run at the end should anyone care to peruse) The engine was built completely to factory specifications save for SRP pistons, a set of Scat rods, and a cam that I don't care to discuss for several reasons. On a very conservative dyno with absolutely no tuning whatsoever, it cranked out 377 HP @ 6000 rpm and made over 300 ft.lbs of torque from 3000 to 6500 rpm on the very first power pull, with a peak of 355 ft.lbs at 4500 rpm. FWIW, at 4000 rpm it was making 352 ft.lbs, and at 5000 it was making 352 ft.lbs. (How's that for a "torque curve"???..more like a torque plateau if you ask me)

It's all in the overall combination. Don't look for one component to be the "magic bullet".
Eric
I read your write up.

I'm not asking you to divulge the cam grind you used but why not choose the grind that Chevy spec'd for the combination? (the "140" cam)...I saw that you only considered the stock Z cam (that cam is not really designed to work with the cross ram) before moving onto "third party" pieces .

I ran into the same issue with the valve cover clearance...what a pain. BTW, stock '69 valve covers should not have drippers.

PS...did you receive my Email RE the Qjets?

I read your write up.

I'm not asking you to divulge the cam grind you used but why not choose the grind that Chevy spec'd for the combination? (the "140" cam)...I saw that you only considered the stock Z cam (that cam is not really designed to work with the cross ram) before moving onto "third party" pieces .

I ran into the same issue with the valve cover clearance...what a pain. BTW, stock '69 valve covers should not have drippers.

PS...did you receive my Email RE the Qjets?
I passed on the Chevy cams for numerous reasons; the factory 30-30 cam already leaves too much on the table in regards to low end power, and the 140 wouldn't help matters much either in that regards. (unpopular fact of the matter is, the 302 is already grossly OVER-cammed from the factory for something that's going to see more street duty than racetrack. The cam specs on the `70 LT-1 should provide some insight as to why I hold that opinion)

This engine needed to have decent street manners as the customers intentions were to drive the car. I knew that I could pick up a considerable amount of low end power without sacrificing everything up top in the process with the right cam timing, of which neither of the Chevy cams offered.

In a nutshell, the factory Chevy cams were great in their day, but there's considerable room for improvement over them with a modern grind, (and here's the important part) [i]provided the engine is equipped with headers and a free-flowing exhaust system.

I have no doubt that with some very minor revisions, that engine would easily crest 400 HP without giving up any appreciable performance at low rpm. With a cam change (similar specs, but moving the LSA/lobe centers around a little bit) and some very minor clean-up on the ports/chambers, it could make 425 without any trouble at all, albeit at the expense of a little low rpm driveability.

But I digress...the intent of that build was to provide acceptable street manners without sacrificing everything upstairs.

Again, it's all in the combination. :bowtie:
Eric

p.s. no email yet

Email was sent to: Eric Jackson <sales@vintagemusclecarparts.com>
I just re-sent.

I did read your article/write up so get the gist of your "objections":bowtie: to original cams. Modern cams have a lot more theory under them (40 years of devlopment will do that:) ) but I get a kick out of the idea of running the vintage compression and cam (it's sort of a nostalgia/sound thing). I can't go into details on how exactly I did it (I promised someone who helped me spec it out that I wouldn't - I'm sure you'll understand) but my little 302 has great street manners, launches hard and pulls like a mad man from 3000 up (and very quickly I might add...I had driven the car for 20 years with the 4 bbl and stock exhaust manifolds and thought I knew it...added the cross-ram and the headers and it completely surprised me...hit 6500 before I knew it!:eek: ) and that's with the "140" cam, stock, un-ported heads and the Stahl 1 5/8" headers.

I should Dyno it then we could compare for fun (BTW, the 377 figure does not surprise me at all...in race trim the same combination gets towards the mid 400's - not bad for a little 302) Bottom line- the cross -ram is not for everyone but it can be very cool.

PS I enjoyed reading about your "little" project
I passed on the Chevy cams for numerous reasons; the factory 30-30 cam already leaves too much on the table in regards to low end power, and the 140 wouldn't help matters much either in that regards. (unpopular fact of the matter is, the 302 is already grossly OVER-cammed from the factory for something that's going to see more street duty than racetrack. The cam specs on the `70 LT-1 should provide some insight as to why I hold that opinion)

This engine needed to have decent street manners as the customers intentions were to drive the car. I knew that I could pick up a considerable amount of low end power without sacrificing everything up top in the process with the right cam timing, of which neither of the Chevy cams offered.

In a nutshell, the factory Chevy cams were great in their day, but there's considerable room for improvement over them with a modern grind, (and here's the important part) [i]provided the engine is equipped with headers and a free-flowing exhaust system.

I have no doubt that with some very minor revisions, that engine would easily crest 400 HP without giving up any appreciable performance at low rpm. With a cam change (similar specs, but moving the LSA/lobe centers around a little bit) and some very minor clean-up on the ports/chambers, it could make 425 without any trouble at all, albeit at the expense of a little low rpm driveability.

But I digress...the intent of that build was to provide acceptable street manners without sacrificing everything upstairs.

Again, it's all in the combination. :bowtie:
Eric

p.s. no email yet

Thanks for the help and ideas guys. Since some others posted pics of their Z's I figured we shouldhttp://img66.imageshack.us/img66/2952/dadscamaroqu0.jpg (http://imageshack.us) show ours. Circa 1978 lol

Thanks for the help and ideas guys. Since some others posted pics of their Z's I figured we should show ours. Circa 1978 lol
Is that Rallye Green?

Yes the car also was origionally equiped with a m22 trans and rear defroster.

Yes the car also was origionally equiped with a m22 trans and rear defroster.
You don't see that with black stripes very often...black vinyl roof I assume? What color was/is the interior?

Yes vinyl roof and black interior. Have you seen any other 69 z's with that original color combo of Rallye green and black stripes? I've only seen 1 or 2 :bowtie:

American Muscle/flowjoe,

Sorry for the hijack guys, but I have a question regarding this subject. As was covered previously the cross rams had a (questionable) reputation on their original small cube, high revving small blocks.

My question is: Does anyone have an idea as to how these manifolds perform when used in conjunction with more modern parts (heads, cam, etc) and/or even with larger displacement engines?

I love the look of these intakes & I would love to run an SY-1. I was just curious if more cubes would mitigate some of the tuning woes involved with their use.

Shane

That would be interesting to find out. I dont see why the intake would not work on a larger cube engine. However, this intake may not be the most efficient for power as the design is 40+ yrs old but looks wise it is hard to beat:bowtie:

Please go over to Team Camaro and hunt up SY1 and chat w/ him.

I ran the old -097 solid cam in my junk301 and loved it even if it is a little-bitty bugger!

pdq67

The Cross rams will always have a mystique about them and looks impressive to many.

I've played with many of them and have and Winters crossram on my 69 DZ. Like someone earlier stated, the old Duntov 30/30 cams were a bit much for the street and even with the better gas we had, they were still a handful to drive. Sure, they sounded impressive but cam profiles from the late 80's to current offer more drivability then what the originals could offer!

I've also got a couple of Offy's and Edelbrock STR-10's and SY-1's and by far the most headaches I've had was dialing in the Offy's with the Webber car set-up! The dual Holley's were a breeze! Not many people like the Edelbrock cross ram and even more people complain about the SY-1 as far as a bolt on and go manifold.

Any cross rams will require some careful thinking and matching of the components. Often the manifolds will require some fuel dams, flow guides or some sort of epoxy work to help. In most cases, the plenum is too large and many overlook the need to have a larger pump shot of the accelerator pump to get less of a bog. Some people have made some "stuffers" to take up the volume so that the carb signal is stronger and more consistent.

If you only think of a cross ram as a laid down tunnel ram, you'll be missing the fact that the air/fuel mixture has some pretty tight turns to make even though the ports may be large and have a long straight shot to the cylinders.

Some of the best engines I've had fun with, have all been larger in displacement. 377's have the larger area and the ability to rev to take the advantages of a good set-up cross ram. Long 6.0" rod 383's can be set-up to run well but two of the best combos I've had fun with has been a 396 & 427 small block with a SY-1 and a single 800 Holley. Very responsive and strong low end but even more midrange to upper rpm torque with very snappy throttle response.

The newer Hydraulic roller cams work well for high performance street but for more response and performance, modern solid rollers are the way to go!

Yeah! Cross Rams are fun, you just got to be willing work on them to get the right combo!

Yes vinyl roof and black interior. Have you seen any other 69 z's with that original color combo of Rallye green and black stripes? I've only seen 1 or 2 :bowtie:

I had a friend with one years ago...fully restored but I think it was white striped. To be honest, It is not one of my favorite colors but you don't see it very often. (I know someone with a '68 Z in Rally green and a someone with a 68 396 car).

Check out this chart:
http://www.camaros.org/exterior.shtml#ColorPercentages

I think that the fuel puddling is addressed with the cast ridges in the base of the intake...especially with the current version of the Offy. To be sure that is an issue with this design in general at idle and very low speeds..personally it has never manifested itself on my car in real world driving situations (although I have no doubt it is most likely happening).

The cross ram is a design that GM went back to in the '80s with the cross fire intakes/engines. It uses the same base casting but with the dual throttle bodies in a modified top plate (and an HEI and engine management "stuff". I think now it is kind of a "dead" technology.

The really cool thing about the '68/69 cross rams is that they were designed specifically for the Z/28 Trans am racing program and nothing else. GM threw a lot of resources at a very specialized item with very limited application and only one purpose...win Trans Am races against Ford. It is one of those pieces laden with mystique and Z/28-ness. I've wanted one ever since I bought my Z in '84) and foudn out that the cross ram existed. Jsut took me 19 yera to get aroudn to doing it...:)

The Cross rams will always have a mystique about them and looks impressive to many.

I've played with many of them and have and Winters cross-ram on my 69 DZ. Like someone earlier stated, the old Duntov 30/30 cams were a bit much for the street and even with the better gas we had, they were still a handful to drive. Sure, they sounded impressive but cam profiles from the late 80's to current offer more drivability then what the originals could offer!

I've also got a couple of Offy's and Edelbrock STR-10's and SY-1's and by far the most headaches I've had was dialing in the Offy's with the Webber car set-up! The dual Holley's were a breeze! Not many people like the Edelbrock cross ram and even more people complain about the SY-1 as far as a bolt on and go manifold.

Any cross rams will require some careful thinking and matching of the components. Often the manifolds will require some fuel dams, flow guides or some sort of epoxy work to help. In most cases, the plenum is too large and many overlook the need to have a larger pump shot of the accelerator pump to get less of a bog. Some people have made some "stuffers" to take up the volume so that the carb signal is stronger and more consistent.

If you only think of a cross ram as a laid down tunnel ram, you'll be missing the fact that the air/fuel mixture has some pretty tight turns to make even though the ports may be large and have a long straight shot to the cylinders.

Some of the best engines I've had fun with, have all been larger in displacement. 377's have the larger area and the ability to rev to take the advantages of a good set-up cross ram. Long 6.0" rod 383's can be set-up to run well but two of the best combos I've had fun with has been a 396 & 427 small block with a SY-1 and a single 800 Holley. Very responsive and strong low end but even more midrange to upper rpm torque with very snappy throttle response.

The newer Hydraulic roller cams work well for high performance street but for more response and performance, modern solid rollers are the way to go!

Yeah! Cross Rams are fun, you just got to be willing work on them to get the right combo!