Stroker 304 Project Build

Greg Taylor · #1 01-02-2009, 08:52 AM

Hey guys,
Finally staring a thread for the stroker 304 I'm building up for my '89 Grand Wagoneer, with a goal of getting 20-MPG out of the AMC V8 in a 4,500 lb. Jeep, with a decent increase in power over a stock AMC 304/360. My 304 is being stroked with a 390 crank, aftermarket forged 401 rods and custom Diamond Racing forged pistons. Net result is approx. 330 cubes and an engine that should put out 300+ HP (not that it matters for a Jeep, but torque should be great!).

I have researched various technologies for improving performance and MPGs and am implementing some of them in this build ... being a guinea pig, so to speak, for those that have shown some interest in them for their AMC builds, but didn't want to jump in head first.

Technologies being employed for engine build:
1) Higher Compression for increased efficiency
2) Cylinder Head Grooves to address detonation with increased compression
3) AMC-specific piston designed for better burn and power
4) Fish Carburetor ... known for an average of 30% more power & 20% more MPGs
5) Swirl Port head design
6) Unique cam design for minimizing overlap ... somewhat resembles a Miller-Cycle engine camshaft design (longer intake duration), which works well with the Fish Carb
7) Roller Rockers
8) Frantz oil filter ... won't make better MPG's or power, but will help keep the engine really clean inside.

Listed below are my build specs and a few of the technologies I am using. I am also including pictures on this thread, as the build-up proceeds.

**** BUILD SPECS - 330" AMC V8 ****
BLOCK: 1979 AMC 304 V8 (milled for Zero-Deck)
Bore : 3.83” (stock 304 is 3.75”)

CRANK: NOS AMC 390 Forged crank (cross-drilled)
Stroke : 3.574” (stock AMC 401)

RODS: 5.858” long AMC 401 I-beam rods 1.001” bushing for floating pin
PISTONS: Custom forged Diamond Racing pistons (Special design for AMCs)
Result in 9.8:1 compression with 58-cc heads

CAM: Crower Turbomaster Hydraulic flat tappet for AMC V8
Advertised Intake Duration : 278
Advertised Exhaust Duration : 260
Intake Duration @ 0.050” lift : 212
Exhaust Duration @ 0.050” lift : 200
Intake Valve Lift w/1.6 Rocker Ratio : 0.461”
Exhaust Valve Lift w/1.6 Rocker Ratio : 0.426”
Lobe Separation : 114

LIFTERS: Rhodes anti-pump up hydraulic lifters (variable duration)
Low RPM = 190 PSI Cranking Pressure
High RPM = 177 PSI cranking pressure

HEADS: 1979 AMC 360 heads. ~58cc Chambers
Heads will incorporate combustion chamber grooves which allow use of 87 octane gas on 10:1 motors … may run E85 at some point

VALVES: Small Block Chevy conversion (w/undercut stems)
INT: 1.94” diameter (stock AMC 304 is 1.787”)
EXH: 1.50” diameter (stock AMC 304 is 1.406”)

ROCKER ARMS: Scorpion 1.6:1 Aluminum roller rockers for AMC V8 (Pedestal-mount setup … modified Ford Pedestal)

HEAD GASKET: Felpro Hyperblue 0.048” compressed thickness for AMC 304
(was originally going to run ROL Xtreme 0.045" thick 360-390-401 gasket ... really trick ... just not on the smaller 304 bore!)

INTAKE MANIFOLD: Offenhauser 360 Equa-flow intake for AMC V8 with Quadrajet pattern

CARBURETOR: Brand new 2.0” bore Fish Carburetor (new limited production run) ... ... very unique & rare carb ... out-performs any other carb in power and MPGs, and can switch between multiple fuels with only minutes of adjustment. Carb has NO JETS.

EXHAUST: Doug Thorley Tri-Y Headers for Full Size Jeeps. 3.0” single exhaust. Modified for Lambda O2 sensor port

TRANNY: TF727 and a Jeep NP208 T-case (2.69 low range)

DIFFS: 3.31:1 Dana 44’s

TIRES: 31x10.5x15 BFG T/A’s

**** PICS ****

jaber · #2 01-02-2009, 09:30 AM

THANK YOU. I cant wait to see how this goes. PLEASE, keep the updates comin'...

yankeedog · #3 01-02-2009, 09:53 AM

thank you my hero

tgreese · #4 01-02-2009, 10:01 AM

Quote:

Originally Posted by Greg Taylor

...torque should be great!...

Yep, I'd think so. Please update as you move along!

Any thoughts about the oversquare ratio 3.83/3.574 = 1.072 and fuel economy?

Jeeptech says the 401 crank is a 3.68 stroke. I presume the 390 is different?

Greg Taylor · #5 01-03-2009, 07:29 PM

Hi guys,
I'll keep the pics and updates coming along as we make progress ... right now we're waiting on the heads to be done at the machinist. Might be a week or two for that, depending on his work load.

The 390 crank has a stroke of 3.574".

As for oversquare ... the stock 304 is 3.75/3.44 = 1.0901, which is pretty close to what I'm building. With a smaller bore piston in the hole, there will be less piston rock and less rotating mass than a 390 or 401, so it should rev faster.

It will be interesting to see what the HP and torque numbers are for this 330" AMC V8. C & D Performance in Texas has built a Super Street AMC 304 engine (not stroked) that puts out 370-HP & 405 ft/lb torque. They have built theirs nearly identical to my short block, except that they are running a roller cam, with probably alot longer duration and lift than I will be ... remember ... I'm also going for MPGs with this thing, LOL! Check out their Super Street AMC engine at www.c-dperformance.com ... scroll down about two-thirds on their main page to see it. If I am remotely in the area of about 330-HP, I'll be pleased as punch, especially if I get the MPGs up, also.

Greg Taylor · #6 01-03-2009, 07:34 PM

Guys,
I just pulled this from Wikipedia ....

A piston engine is undersquare or longstroke if its cylinders have a smaller bore (width, diameter) than stroke (length of piston travel). This can be a negative trait, since a longer stroke usually means greater friction, more stress on the crankshaft, and a smaller bore means smaller valves which restricts gaseous exchange; however, with the aid of modern technology, these are not the large problems that they used to be. An undersquare engine usually has a lower redline than an oversquare one, but it may generate more low-end torque. In addition, a longstroke or undersquare engine can have a higher compression ratio with the same octane fuel compared to a similar displacement engine with a higher bore/stroke ratio. This also equals better fuel economy and somewhat better emissions. An undersquare engine does not overheat as easily as similar oversquare engine. Engines can be modified with a "stroker" crankshaft, which increases an engines stroke from stock, increasing torque.

jpcoutts · #7 01-03-2009, 07:39 PM

This will be interesting. I hope it goes smoothly and fast so we all can see the results!

jeepjerry · #8 01-03-2009, 08:29 PM

Where did you get your Diamond pistons from? Did you have them made? They aren't Alfano Performance pistons are they?

Greg Taylor · #9 01-03-2009, 08:41 PM

Quote:

Originally Posted by jeepjerry

Where did you get your Diamond pistons from? Did you have them made? They aren't Alfano Performance pistons are they?

Yes, they're Nick's design. I was going to buy them direct through Diamond, since they're about 30 minutes from where I work/live, but Nick got them for me at a better price and a higher end design piston than Diamond would have sold me direct. Either way, they're still pricey, LOL!

jeepjerry · #10 01-03-2009, 09:03 PM

Quote:

Originally Posted by Greg Taylor

Yes, they're Nick's design. I was going to buy them direct through Diamond, since they're about 30 minutes from where I work/live, but Nick got them for me at a better price and a higher end design piston than Diamond would have sold me direct. Either way, they're still pricey, LOL!

Yeah, They arent cheap. Im running them in the 360 we're building for my javelin. After seeing what happened to a 390 he was rebuilding for a Rebel machine with less than 2000 miles on the previous rebuild and grenadeing a cast piston, I opted to go with the forged. I got a nice slightly used crane cam for free out of it because the customer went roller.

They are nice pistons for sure.

Greg Taylor · #11 01-09-2009, 05:05 PM

Hey guys,
We're still waiting on the cylinder heads to be completed, so the post is still in limbo land.

Also, I'm switching to the Holley Street Dominator intake, instead of the Offy 360 intake.

More information and pics to come in about a week.

jeepjerry · #12 01-09-2009, 05:43 PM

Why do you want to go with a Holley Street Dominator? More torque?

The runners on the Holley are very small compared to an Offy 360 or even stock. The SP2P runners are small also but are bigger than the Holley.

Just wondering.

I am anxious to see how this motor is going to run. I think its going to do pretty good.

Greg Taylor · #13 01-09-2009, 07:30 PM

I've run the Street Dominator in the past on both a mild-built 401 (Edelbrock cam, Hedman headers, HEI, 4-bbl) and very mild stock 360 (Edelbrock TES headers, TFI, 4-bbl). It's a really nice intake for torque and makes ample power for the stock RPM range. The 401 setup ran a Holley 570-cfm Street Avenger and a Poweraid carb spacer. It performed awesomely!

The Offy I was going to run does have huge runners, but it's single plane, so torque would suffer in low-mid RPMs ... as would MPGs. The Street Dominator will keep port velocity up, generating more torque and better MPGs.

My buddy helping me build the stroker is also running it on a built 304 in his 69 Javelin. 9.5:1 compression, Edlebrock cam, 425-cfm Carter 4-bbl & Jeep AW4 2wd tranny. I will tell you, that 304 runs like a nicely built 360 ... it acts like the 5.0L Mustangs as far as performance and grunt. It will light the tires off nicely and absolutely flies.

I think a lot of AMCers don't like the Street Dominator, or the SP2P, because air flow suffers above 4,800 RPM and power drops off. Race and Street Racers would benefit from a bigger intake for higher RPM use. Jeeps however, benefit from the smaller runners, netting more torque and MPGs in the low-mid RPM ranges. The Holley still seems to perform in the upper RPMs, as well.

I also have an Edelbrock SP2P, but am opting for the Holley intake. The SP2P will be going up for sale ... perfect for a rock crawler.

jeepjerry · #14 01-09-2009, 07:40 PM

Makes Sense! Can agree with that.

I suppose the runners cant flow less than the intake valve will let through anyways.

Im in the process of putting together a 73 304 to put in my Cherokee. Its got stock internals with fairly low mileage and is in great condition. I lapped the valves quick and put new seals in. Its getting a Crower RV cam, SP2P intake, headers, and an edelbrock carb. The way you say that Javelin runs makes me think that my 304 will push my cherokee fine.

Greg Taylor · #15 01-09-2009, 07:46 PM

Jerry,
Your 304 should run just fine with that combo in the Jeep. The only difference I can really see is that Rick's 304 has 290 pistons in it, making it 9.5:1 compression ... I assume you're running the 8.3:1 pistons.

If you need a SP2P, I have one available.

Greg Taylor · #16 01-09-2009, 07:53 PM

Guys,
Here are a couple more forum posts on the Holley Street Dominator intake. Both speak well of it ... which is my experience as well!

http://www.ifsja.org/forums/vb/showthread.php?t=3865

http://www.ifsja.org/forums/vb/showthread.php?t=14135

jeepjerry · #17 01-09-2009, 07:54 PM

Yeah its the stock 8.3:1 which isnt terrible, could be 7.5:1.

Ive got the intake already but thanks for the offer!

Should have mine running in a few weeks, just have to get a double roller timing chain and intake gasket from Nick and finish assembling it.

Greg Taylor · #18 01-09-2009, 08:02 PM

Yeah, 7.5:1 would be worse, LOL ... of course, my stroker was originally going to be 7.8:1 ... and turboed to about 25 lbs boost.

Post up some pics when you get a chance!

jeepjerry · #19 01-09-2009, 08:02 PM

Quote:

Originally Posted by Greg Taylor

Guys,
Here are a couple more forum posts on the Holley Street Dominator intake. Both speak well of it ... which is my experience as well!

http://www.ifsja.org/forums/vb/showthread.php?t=3865

http://www.ifsja.org/forums/vb/showthread.php?t=14135

Hmm, they favor the Holley over the SP2P. Nick Alfano offered to sell me a Street Dominator cheap a while back but i passed on it.

Oh well the SP2P will be better than a 2 barrel on my 304.

Greg Taylor · #20 01-09-2009, 08:23 PM

Quote:

Originally Posted by jeepjerry

Hmm, they favor the Holley over the SP2P. Nick Alfano offered to sell me a Street Dominator cheap a while back but i passed on it.

Oh well the SP2P will be better than a 2 barrel on my 304.

For what Nick builds, the Holley is inadequate ... not enough RPM range. Give him a call and *ask* about it again, LOL!

If I weren't running the Fish carb, then I would be running an Offy Dual Port 360 intake with a Quadrajet. The Offy d-port isn't suited well for the Fish carb, since it's a SINGLE BARREL design. Check it out at :

http://s246.photobucket.com/albums/g...a/Fish%20Carb/ ... this is a 1 5/8 bore carb. I'll be getting a NEW 2.0" bore carb & adapter, which will look like this :

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