250 crossflow hot up

[Fknclevo 3]

5kish at a crossflow can stretch the budget 

but want is the best go if i dont really want to be changing pistons and bumping comp up

what’s the biggest/cam i can run hydraulic v solid

want to throw a big cam and supporting mods (roller rockers springs etc etc)

ice ignition kits available good or no?

600 holley 4 barrel and manifold?

have a 650 mechanical secondary’s here to big?

even if i dejet

good balancer and flywheel?

arp rod bolts needed or not?

if its not crazy more expensive dont mind throwing more money at it for big cam big comp just dont how worth it really is?

looking for a car that’ll light the tyres up and just give it a bit more go

what would good cam operating range be 

seen cams like crow cam 14806 is this way to big for standard comp?

 

[deankxf 20,694]

1 hour ago, Fknclevo said:

seen cams like crow cam 14806 is this way to big for standard comp?

https://crowcams.com.au/product/ford-crossflow-solid-1

 

1 hour ago, Fknclevo said:

5kish at a crossflow can stretch the budge

I don't think $5k will go far these days. if you need to upgrade the diff, exhaust, trans, converter also. you'll be way off. 

 

I don't have the answers, but with a cam that big will surely need MUCH more compression to compensate . (you could ask Crow, they did reply to My questions on a different cam once)

Also, what diff ratio are you going to use? i had a crossflow 30yrs ago that was 2500-5500 rpm range with 2.92 diff ratio and auto and stock converter and it was like starting off in second gear until it got to about 40kmh then came to life. a 2500 high stall or manual would have helped a lot. 

can you even get a 3500 high stall for what trans you are using if Auto? (likely going to cost a LOT also)

 

 

RPM Range	Part No.	Duration				with 1.73 Rocker		Lobe Sep Angle	Lash
		Advertised		@.050”
		IN	EX	IN	EX	IN	EX		IN	EX
3500 - 6500	14806	281°	294°	245°	255°	0.564	0.585	108	.018"	.022"

 

 

"FITTING NOTES"
 

Must use performance springs.

Must use performance retainers.

Machining required to fit these components.

Must use performance seal.

Converter stall speed should be equal to or greater than the minimum RPM of the cam power range

 

 

[Fknclevo 3]

15 minutes ago, deankxf said:

https://crowcams.com.au/product/ford-crossflow-solid-1

 

I don't think $5k will go far these days. if you need to upgrade the diff, exhaust, trans, converter also. you'll be way off. 

 

I don't have the answers, but with a cam that big will surely need MUCH more compression to compensate . (you could ask Crow, they did reply to My questions on a different cam once)

Also, what diff ratio are you going to use? i had a crossflow 30yrs ago that was 2500-5500 rpm range with 2.92 diff ratio and auto and stock converter and it was like starting off in second gear until it got to about 40kmh then came to life. a 2500 high stall or manual would have helped a lot. 

can you even get a 3500 high stall for what trans you are using if Auto? (likely going to cost a LOT also)

 

 

RPM Range	Part No.	Duration				with 1.73 Rocker		Lobe Sep Angle	Lash
		Advertised		@.050”
		IN	EX	IN	EX	IN	EX		IN	EX
3500 - 6500	14806	281°	294°	245°	255°	0.564	0.585	108	.018"	.022"

 

 

"FITTING NOTES"
 

Must use performance springs.

Must use performance retainers.

Machining required to fit these components.

Must use performance seal.

Converter stall speed should be equal to or greater than the minimum RPM of the cam power range

 

 

i have toploader to go behind it and bg diff with 28 spline axels mini spool and 3.55 gearing i also have a overkill fuel system that it won’t need that i can put in it if i have.

it’s mainly 5kish for engine parts the rest is a different budget

[Boingk 884]

Hi mate, best bet would be to go through the whole engine. I've been down this path and the best bang for the buck was having a set of 200ci pistons for a 1966 Mustang in the block. Cheap casties, but they bumped the compression right up to 11:1 or so with the alloyhead motor.

That let me run the entry level Crow mechanical flat tappet camshaft for a more aggressive ramp rate, it had about 232@50 and 570 lift from memory, so equivalent to about a 250@50 hydraulic or so. To run that cam I needed rockers, springs, retainers and pushrods. The pistons gave me the compression I needed for it to not be a dog off the line.

 

Along with a 3" single exhaust, long oval straight-through truck muffler and turndown at the diff it had extractors, intake, ADL2 ignition through a Blaster solid state coil and Holley Brawler carb on an Aussiespeed intake.

 

The thing went like the clappers with a four speed manual behind it in my XF ute, about the same as a modern BA-BF XR6 (non-turbo) which isn't bad for an old pushrod job.

 

I think if you're not putting money into a new block with a bit of machining for some basic cast pistons and new bearings you'll probably be disappointed.

 

If you aren't running new pistons, I'd be looking more at the 14550SS as a maximum which has the following:
Performance cam heaps of bottom end & mid range, Street /Stock speedway :: 2200 - 5200rpm :: 141550S :: 290 295 duration :: 219 224 @50 :: .510"in .510"ex :: 106 lobesep

 

That would give you a good streetable engine without opening her right up. You'll still probably need springs and pushrods, though, or you'll just end up with a mess when the stock pushrods bend - assuming they havent already on the stock motor! They are a very long pushrod compared to most basic automotive engines, especially V8's, and aren't terribly durable once you get over about 4500rpm.

 

TLDR?

 

So, intake and reasonable carby - I'd highly recommend a 4412 (Holley 500cfm two barrel) on the stock manifold or a slightly improved unit. Easily and widely available and beats the pants off the tiny little 350 which is too small IMO. I wouldn't spend $800 on the Aussiespeed manifold as its better spent elsewhere at this level. Throw a basic HEI style dizzy on or get a timing box and run it from the TFI style (EFI) dizzy so you can set your ignition curve properly. Get extractors and sort the exhaust. Now decide on the camshaft (note above) and install the supporting mods.

 

That's about it.

 

It won't be a world beater but it'll sure have a lot more get up and go than the current 100hp lump in there, and feel/sound a lot more aggressive on the road. The 3.55 rear end will get old quick, though, as you'll pull significant revs on the highway. I would leave it til dead last and see how you go with the stock 2.92 unit.

 

Cheers - boingk

 

EDIT: Saw you had a 650 mech-sec. Perfect but I'd be wary of using the back barrels too much. I ran a 650 on my solid cam job and it was way too much carb for it.

[Fknclevo 3]

On 3/8/2024 at 11:09 AM, Boingk said:

Hi mate, best bet would be to go through the whole engine. I've been down this path and the best bang for the buck was having a set of 200ci pistons for a 1966 Mustang in the block. Cheap casties, but they bumped the compression right up to 11:1 or so with the alloyhead motor.

That let me run the entry level Crow mechanical flat tappet camshaft for a more aggressive ramp rate, it had about 232@50 and 570 lift from memory, so equivalent to about a 250@50 hydraulic or so. To run that cam I needed rockers, springs, retainers and pushrods. The pistons gave me the compression I needed for it to not be a dog off the line.

 

Along with a 3" single exhaust, long oval straight-through truck muffler and turndown at the diff it had extractors, intake, ADL2 ignition through a Blaster solid state coil and Holley Brawler carb on an Aussiespeed intake.

 

The thing went like the clappers with a four speed manual behind it in my XF ute, about the same as a modern BA-BF XR6 (non-turbo) which isn't bad for an old pushrod job.

 

I think if you're not putting money into a new block with a bit of machining for some basic cast pistons and new bearings you'll probably be disappointed.

 

If you aren't running new pistons, I'd be looking more at the 14550SS as a maximum which has the following:
Performance cam heaps of bottom end & mid range, Street /Stock speedway :: 2200 - 5200rpm :: 141550S :: 290 295 duration :: 219 224 @50 :: .510"in .510"ex :: 106 lobesep

 

That would give you a good streetable engine without opening her right up. You'll still probably need springs and pushrods, though, or you'll just end up with a mess when the stock pushrods bend - assuming they havent already on the stock motor! They are a very long pushrod compared to most basic automotive engines, especially V8's, and aren't terribly durable once you get over about 4500rpm.

 

TLDR?

 

So, intake and reasonable carby - I'd highly recommend a 4412 (Holley 500cfm two barrel) on the stock manifold or a slightly improved unit. Easily and widely available and beats the pants off the tiny little 350 which is too small IMO. I wouldn't spend $800 on the Aussiespeed manifold as its better spent elsewhere at this level. Throw a basic HEI style dizzy on or get a timing box and run it from the TFI style (EFI) dizzy so you can set your ignition curve properly. Get extractors and sort the exhaust. Now decide on the camshaft (note above) and install the supporting mods.

 

That's about it.

 

It won't be a world beater but it'll sure have a lot more get up and go than the current 100hp lump in there, and feel/sound a lot more aggressive on the road. The 3.55 rear end will get old quick, though, as you'll pull significant revs on the highway. I would leave it til dead last and see how you go with the stock 2.92 unit.

 

Cheers - boingk

 

EDIT: Saw you had a 650 mech-sec. Perfect but I'd be wary of using the back barrels too much. I ran a 650 on my solid cam job and it was way too much carb for it.

thank you for your advice i will takw this onboard