I need 350HP out of my 289. How can I do it?

[Jwink25]

I would like to get about 350HP out of my '67' 289. I will have the engine block reworked and have the internals balanced.

 

I was thinking on using:

 

Roush World Class heads

Comp 280 Magnum cam

I'll be running about 9.5 to 1 CR

Edelbrock Performer RPM manifold

Headers...whatever will fit.

 

Can anyone give me an idea what this setup could get me? Any hints or tips would be great. I have never built up a 289 before. Also, this car will see mostly street action with a few trips to the strip. So good drivablity should be taken into account. I don't mind a ruff idle...just not to rough. Anyone ever run a 280 Magnum cam before?

 

Thanks!

 

Jason Winkfield

[blueovalz]

I don't have any numbers in front of me, but 350hp on a stroke of less than 3" is going to require some RPM, which is why I love this motor. The good thing about a lumpy cam in a small lightweight car (like our Zs) is that drivability is usually not a problem, even with an aluminum flywheel. I'm not an expert here, but will give some suggestions which I found works well on the 289. An old Torker intake (not the TorkerII) is a real good intake, and will provide a broad range (considering it is a single plane intake) all the way up to 7k. The F4B is also an excellent dual plane intake too. I would stick with a carb in the 650 range, but I very successfully us an old 780vs (3310) that works very well. I'm running a cam that has 250 degrees duration at .050 with net lift of .544" on 112 separation. It is a mild (by solid roller standards) solid roller cam. With this cam, 10.3 compression ratio, Victor Jr, 780cfm, 1.75" medium length tube headers, and Motorsport J302 heads (BTW, there are some on EBay for sale). I've been told by my cam grinder that he did not feel he was overstating this combo at being around 377hp.

[Kevin Shasteen]

As Terry illuded to your small displacement engine w/3" or less of a Stroke is going to require "HIGH RPM" to obtain your 350hp goal.

 

In order to obtain a 350hp rating w/such a small displacement you will need to rev up to at least the 6.5-7k rpm's. This means your low rpm will be pathetic; as you claimed-driveability is preferred....dont think you can have both!

 

If driveability is an issue I would not use the 280 cam as idle will be in the 850-900rpm neighborhood and low rpm idle Dynamic Compression Ratio (DCR) will stink if all you are shooting for is a 9.5:1 Static Comp.Ratio (SCR). DCR & SCR should compliment each other....not oppose each other.

 

If you were to go w/the 280H cam your Intake Valve Closing (IVC) would occur at 66* ABDC. In a 289 (with a 2.870" Stroke, 5.155" Rod, 1.608 Piston Compression Height...then as that IVC occurs your cylinder would only have .762% Volume Remaining in the cylinder: the amount of Volume Remaining after IVC is effected w/Displacement. The less displacement of the engine-the greater % of Volume Remaining as a requirement also increases; likewise-more displacement means you can get away with less % of Volume Remaining after the IVC occurs...such as in a big block.

 

Anyway, back to your engine. This minimal amount of Volume Remaining would require at least a 10.5:1 to 11.0:1 SCR so that low rpm [driveability] would not suffer...but with that SCR you are pushing the Pump Gas limits; better make sure you are running Alluminum Cyl.Heads.

 

If (low rpm engine vacuum) low rpm driveability is a concern then maybe you should think about a

260, 262, 268H Cam instead.

 

If most of your driving will be done on the street and this car is also your main source of transportation-an engine that has a poor Dynamic Compression Ratio (DCR) is not what you want. Why put in a cam whose power comes into play after 4500rpm's; you said yourself most of your driving will be on the street(?). With a smaller cam your engine will still rev to 6k; it will merely be your limit which also means your power range will be 3.5k rpm's....much better for the street.

 

FWIW: the Xtreme Energy 262 Cam would allow for a nice idle at/or around 650-750rpm's and would still require a 10:1 SCR but offers an 8.5:1 DCR. This also requires a Total Combustion Chamber Volume of 64.88cc's. This means your Quench, Compressed Head Gasket cc's, Piston Dome/Dish cc's and Combustion Chamber cc's must add up to a total of 64.88cc's to obtain this 10:1 SCR and with the 262cam allows for an 8.5:1 DCR. All this translates into a good low idle with great engine vacuum at that low idle: AKA: Good Low Rpm Driveability.

 

Just my thoughts: take it or leave it; hope it helps.

 

Kevin,

(Yea,Still an Inliner)

[Jwink25]

Thanks for the info. guys!

 

Jason

[Guest Anonymous]

This is what I was considering doing for my Mustang before I found a 351W. I don't know if it would work, but it should.

Turn the 289 crank for 2.1" SB Chevy rod journals and use narrowed Chevy 400V8 rods with KB #355 (331 SB Ford stroker) pistons. Use mildly ported late '80s 5.0L heads with hardened seats, stainless valves and Crane/Comp. Cams roller tip rockers for the 68cc chambers to lower compression to around 8:1. Install a single plane intake and fashion an adapter plate to mount a turbocharger from a '79-'83 Buick V6 at the carb flange. Replace the Q-jet with a Holley spreadbore 4bbl with a 50cc accelerator pump. Tap the oil lines to and from the turbo, use an hv oil pump with an ARP shaft, install an hp fuel system and feed the turbo from cast iron manifolds and a stainless Y-pipe. 10-12 lbs of boost should get you 350hp easily even with a stock cam and be very driveable.

[Breeze77z]

Sorry if this is irrelevant to the 289, but my dad used to work with Summit, TrickFlow more specifically. And their test-mule GT mustang equipped with Twisted Wedge Heads, FPP E303 Cam, TrickFlow Street Upper and Lower FI intake, and 60mm TB was pushin 360hp at the flywheel (in house dyno...nice:)! ). 347 Stroker put it into low 400's, and small 6-10psi supercharger boost put them into the 500's. Oh, it had a MSD ignition box too (the common one, the name slips my mind right now). I don't know any numbers for a carb setup, but if anybody wants more specific numbers for the FI i will be happy to ask my dad again.

 

That mustang GT was runnin 12.75 in the 1/4 (with blower i think? but maybe not), so i'm sure a Z would do just nicely.

Pat.

[Guest Anonymous]

You could find an 87-92 5.0 HO engine,these had forged TRW pistons and a roller block.A hydro roller cam will get better drivability,more horsepower,better idle and pull better vacuum at idle.302 HOs had low tension rings,these do not wear out the bores.Most times a new oilpump,a ring and bearing kit will bring one back to life.The only machine work is running a hone in the cylinders and cleaning up the block.

 

My combo consists of reringed 1990 model roller shortblock,a Trick Flow Stage 1 cam,Torker 289 intake (the one blueovalz mentioned),Edlebrock 600 CFM carb and a set of CNC ported 87-95 run of the mill non-Cobra Mustang heads(casts E7TE).These have stainless 1.90 I and 1.6 E valves,solid bronze valve guides and the springs on the base set of heads are good enough for the TFS #1 cam.

 

This mild combo put down 256 rwhp,assuming a 17% loss for the AOD trans is about 310 fwhp.This tune was done with a remote tach and a vacuum guage in the back yard.I assemble all my engines myself.This was just two dyno runs to get the power curve.No tuning was done.

 

I could add some better headers,more agressive cam,replace the stock stamped 1.6 rockers with roller rocker with a 1.7 ratio and add a Holley 650 double pumper carb.I could get a dyno tune done and that should hit the 350 fwhp mark.

 

This link will bring you to a site that has a 400 fwhp 302 build up

http://www.jason.fletcher.net/tech/sherman/sherman.htm ,it uses a similar Isky 280 cam.Its worth a look see.

 

Using the great flowin' iron Roush heads,I feel your 289 will make the power with 10-1 comp.Remember all a 302 is a 289 with another .013 stroke.Not really enough to make a big difference in power between the two.Its only 13ci,a 302 would need 1.32 hp per ci,a 289 would need 1.38 to make 400 fwhp.You can get these numbers with carful parts selection.