CYLINDER HEADS

[wjtom]

well i talked to edelbrock today.seems they have looked into making a cylinder head for the 4.0/258 but didnt think the demand was there.i told them they should rethink that with the amount of companies making strokers today and the amount of us doing these.plus the 258 guys looking for an upgrade.so give them a call and let them know there is a demand for a real performance cylinder head for the 4.0!

[Cheromaniac]

so give them a call and let them know there is a demand for a real performance cylinder head for the 4.0!

Preferably at a price well below the $2000+ that Hesco charge for their aluminum head.

[wjtom]

would seem by the conversation somewhere between the cost of one cylinder head and a pair of v8 heads.which would make sense.

[shawnxj]

should post up an email address for whoever is in charge of this so we can spam him into submission

[wjtom]

if you meant me,why?crane has a roller cam in the works that was suppossed to be available last year but they broke the hobbs for cutting the cam gear,edelbrock looked into making a head for these but didnt think the demand was there.if nobody calls these companies asking for this stuff it will never get made.personally id love to have a roller cam as there is no downside to them plus having options for heads would be nice.how about a pump gas 400hp 4.7?just like the cutout fender flares for the wj,enough phone calls and bushwacker finally made them.....

[I6FAN]

When the HESCO aluminum head first came out, I swear I saw an aluminum head offered by Patriot. And then shortly after, the only head available was HESCO's. Can anyone else verify this? Who makes the head for HESCO [overseas probably]? Is Patriot a casting house or just a finishing shop? You can get a really nice set of AFR heads for ~$1400; that's 8 set of valves and two machining set-ups. I can't see paying more than a grand for a single aluminum head; realistically $875-$950. Maybe a company like AFR could do something; they are pretty customer support savvy!

[SilverXJ]

IIRC the Hesco head was originally made by Patriot. Then Hesco bought the rights to it.

[Plechtan]

I have a Hesco head and it is really just a copy of the factory head. The flow numbers are nothing to write home about. It has some advAntages like less weight and the ability to run higher compression with regular gas. The Hesco head was made to sell through Mopar performance and had to be Emissions compliant. It has a CARB number and can be installed on vehicles in California. so it was not really designed as a radical improvment.

The general head design is not the greatest, A crossflow head would be much better. If you really want to get some HP onto of you stroker, i would just go with a turbo. Best bang for the buck.

You can spend a ton of money and if you are real lucky, you will get close to 300hp out of you totaly built stroker. more likely in the 260-275 hp range. On a well built motor with moderate modifications the turbo can get you way over 300 hp without a bunch of expensive parts. ( like $2,000 cylinder heads). Run it on E85 and you can get crazy HP.

I think 4.6 and 4.7 strokers are great. They can be built for a reasonable cost and are reliable and have a ton of torque. Once you try and build them into some high HP motor, you are just wasting your money.

Here is a comaprison for you, Built 4.6 motor, around 290hp and runs on premium fuel. Chevy trailblazer (stock) inline 4.2L motor, 290hp, runs on regualr gas. To make the Jeep motor perform like the chevy motor, all you need is a crossflow head, double overhead cams and 4 valves per cylinder. I don't think anybody is going to be making a head like that real soon for the jeep motor.
The Stroker is what it is, if you want big numbers, boost it. It is the only you are going to get large ammounts of ait through that cylinder head,

[Cheromaniac]

On a well built motor with moderate modifications the turbo can get you way over 300 hp without a bunch of expensive parts.

Yup. Just boost this engine combo and you'd easily exceed 300hp/400lbft:

4.6L modified "poor man's" stroker

Jeep 4.2L 3.895" stroke crank
Jeep 4.0L 6.125" rods
Keith Black UEM-IC944-020 forged pistons
9.25:1 CR
Stock 4.0 camshaft
Ported HO 1.91"/1.50" cylinder head
Mopar/Victor 0.043" head gasket
0.070" quench height
Ford 24lb/hr injectors for '87-'95 engines, Accel 24lb/hr injectors for '96-'04 engines, '98 Chevy LS1 25.2lb/hr injectors for '05-'06 engines
248hp @ 4900rpm, 306lbft @ 3250rpm ('87-'95 camshaft)
245hp @ 4800rpm, 315lbft @ 3000rpm ('96-'04 camshaft)

This is a great stroker build for a mild supercharger/turbo application with up to 6psi of boost. The 4.0L connecting rod/IC944 piston combination offers 155g less reciprocating mass than the 4.2L rod/677P piston combination (1275g v 1430g), thereby giving this engine a potentially higher rpm capability than the traditional "poor man's" stroker.

[Jim K in PA]

With this quench height and compression ratio, the combo below would be a premium fuel only setup, yes?

Yup. Just boost this engine combo and you'd easily exceed 300hp/400lbft:

4.6L modified "poor man's" stroker

Jeep 4.2L 3.895" stroke crank
Jeep 4.0L 6.125" rods
Keith Black UEM-IC944-020 forged pistons
9.25:1 CR
Stock 4.0 camshaft
Ported HO 1.91"/1.50" cylinder head
Mopar/Victor 0.043" head gasket
0.070" quench height
Ford 24lb/hr injectors for '87-'95 engines, Accel 24lb/hr injectors for '96-'04 engines, '98 Chevy LS1 25.2lb/hr injectors for '05-'06 engines
248hp @ 4900rpm, 306lbft @ 3250rpm ('87-'95 camshaft)
245hp @ 4800rpm, 315lbft @ 3000rpm ('96-'04 camshaft)

This is a great stroker build for a mild supercharger/turbo application with up to 6psi of boost. The 4.0L connecting rod/IC944 piston combination offers 155g less reciprocating mass than the 4.2L rod/677P piston combination (1275g v 1430g), thereby giving this engine a potentially higher rpm capability than the traditional "poor man's" stroker.

[Cheromaniac]

With this quench height and compression ratio, the combo below would be a premium fuel only setup, yes?

Nope. My stroker has the same CR and a 0.088" quench but it'll run comfortably on 91 octane even on 120*F summer days. I've even run it on 87 octane in the "winter" months.

[jsawduste]

With this quench height and compression ratio, the combo below would be a premium fuel only setup, yes?

Nope. My stroker has the same CR and a 0.088" quench but it'll run comfortably on 91 octane even on 120*F summer days. I've even run it on 87 octane in the "winter" months.

Careful Dino. I`d be cautious about fuel blending between your country and ours. Not sure how the "additive packages" between the 2 countries would compare. As it is you see a difference between summer and winter blends in your own country.

Over here we are faced with fuels that are laced with varying degrees of ethanol and I`d wager quite different formulations then what you run. Honestly, I really do believe the success or failure of the "poor mans" recipe has a lot to do on how its fed.

Just saying, OK ?

[Jim K in PA]

I was just going to say something similar with respect to what "premium" is and how it is categorized as such. My question was a bit vague in that respect.

I think it would be a stretch to run a 9.25:1 CR iron headed stroker with a quench of .088" on US 87 octane fuel without detonation.

I think an aluminum headed stroker with a 9.5:1 CR and a quench under .050" will run on US 87 octane fuel without detonation on normal advance curves.

That's my intended build plan, anyway.

Careful Dino. I`d be cautious about fuel blending between your country and ours. Not sure how the "additive packages" between the 2 countries would compare. As it is you see a difference between summer and winter blends in your own country.

Over here we are faced with fuels that are laced with varying degrees of ethanol and I`d wager quite different formulations then what you run. Honestly, I really do believe the success or failure of the "poor mans" recipe has a lot to do on how its fed.

Just saying, OK ?

[dwg86]

I ran 9.25 scr / 7.8 dcr with .043 quench, polished combustion chambers. No detonation running 87 octane...not even in hot Atlanta summer weather.

[jsawduste]

I ran 9.25 scr / 7.8 dcr with .043 quench, polished combustion chambers. No detonation running 87 octane...not even in hot Atlanta summer weather.

Ahh but your compression numbers are relatively low and the quench is within the respected numbers. Secondly (or is it thirdly) the chassis set up will have a play in things also. A vehicle with low numerically final drive ratio vs. a higher numerically ratio loads the engine differently.

With no disrespect to Dino, I have and will continue to be critical of the PM strokers. There is simply to much compromise and way to many variables to generate a one size fits all mentality.