2V head shave

xrwagon

Well-known member
Ok so my 2V head on my 200 isn’t working out as good as i thought, we didn’t shave the head due to going supercharged, i have brought a manifold etc, but by the time i do it, i may as well do custom pistons. For now though a 250 2V head on my 68 200 has lost to much comp, its been breathed on, the manifold has been heavily modified, the pipes modified again, and I’ve gone 1 tenth quicker in the 1/8th mile and maybe 2 tenths in the 1/4, couldn’t pull the skin off a bowl of custard. Im pulling the had off Sunday and going to have it shaved, i have adjustable rocker gear etc, i need to measure piston to deck height, but from memory the head cc’ed at 54 or 52, a 200 stock comp is 9.2.1 with a steel shim head gasket, which i had on last log head but it got damaged. So will have the thick head gasket. Im thinking a 60thou shave. Next bottom end will be a 250, and thats only due to more parts availability and crossflow Ford compatibility, theres not much space for the pulleys etc, all has to be a one off on a 200. If i have the funds I’m going to whack a solid cam in, i have a manual and 3.5’s.
 
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xrwagon":11jq2o1s said:
Thank you, now the other issue, how to go faster.



xrwagon":11jq2o1s said:
Ok so my 2V head on my 200 isn’t working out as good as i thought, we didn’t shave the head due to going supercharged, i have brought a manifold etc, but by the time i do it, i may as well do custom pistons. For now though a 250 2V head on my 68 200 has lost to much comp, its been breathed on, the manifold has been heavily modified, the pipes modified again, and I’ve gone 1 tenth quicker in the 1/8th mile and maybe 2 tenths in the 1/4, couldn’t pull the skin off a bowl of custard. Im pulling the had off Sunday and going to have it shaved, i have adjustable rocker gear etc, i need to measure piston to deck height, but from memory the head cc’ed at 54 or 52, a 200 stock comp is 9.2.1 with a steel shim head gasket, which i had on last log head but it got damaged. So will have the thick head gasket. Im thinking a 60thou shave. Next bottom end will be a 250, and thats only due to more parts availability and crossflow Ford compatibility, theres not much space for the pulleys etc, all has to be a one off on a 200. If i have the funds I’m going to whack a solid cam in, i have a manual and 3.5’s.



Its okay. Well, not the going slower part, but you're stuck between new priorities, a normal place to be when using kick ar$e great gear on a stock engine. Its now more badly matched than a street 1970 Boss 429...its got all the great gear but parts of it are so down tuned, not of the bad bits are getting a chance to 'act up'. You know, "when I'm good I'm very good, but when I'm bad, I'm better..." theres no outlet for Marilyn Monroe to missbehave without some better acting conditions.

Principally, seven things are no happening.

Firstly, 1.The size of the huge 42.5 mm diameter intake ports takes the gas speed down, and any modification to the 2V intake will hurt its peak power potential. Grinding out intakes and smoothening them out is always the wrong move for a 3.3. The intake must have microtexture to keep fuel in suspension, and the stock Ford alloy casting is poor, and prone to leaking. Those things rob some of the mid range power between gear changes. 2-bbl Holleys are a little harder to set up, its common for them to need a flush out and extra attention, especially setting up the accelerator pump. The valve gear needs to be spot on with perfect lash and bleed down, DUI needs certain things(im sure its close though if one our our forum experts has been helping), and if compression is down, the extra 50 hp potential is being partly lost.

The power is hiding in

2. the stock cam (which worked better with the former heads moderate air flow and compression ratio, so you are now really undercammedand very under compressed without the extra compression from another 8 cc's of chamber. You can carry 11:1 with that cam and head, go down to a 40 cc chamber.But when you go supercharged, you'll then want the 60 cc chamber volume).
3. the intake changes,
4. the carb,
5. the ignition timing, and
6. some time might need to be spent checking the status of the timing chain, and its effect on the cam timing. 47 years does that...
7.You've possibly lost a little scavenging on the exhaust changes.

You'll get there.

And to show you there are no hard feelings, you can contact me on the spawn of balzebub, um, facebook...https://www.facebook.com/profile.php?id=100009639076135

There. You forced me to the dark side, Azza. PM me on ucp.php?i=pm&mode=compose&u=130, and I'll putcha on my friends list.

Yoo nasty....
 
Yeah i figured most of this, I’ve gone overkill on flow and exhaust, I’ve heard of this happening now to a few guys, should have known prior, would have been good, i figure for the blown combo that custom dished pistons will add some help with lowering the comp if i shave this head, I’m playing devils advocate, so with the alloy head on a 200 are they having similar issues. I reckon I’ve got just under 100 hp, not the 120 i thought i might have, now i have to play catchup, have egg on face for doing this conversion and going 1 tenth quicker, plenty to check on.
 
Great exhausts are around everywhere, so its common for engines to over scavange now. It happesn in NASCAR, AVESCO and on your car...the ideal power curve is stalling, and driving your torque rpm and power rpm points very close together.

Brad Gridwood used to reduce his exhasut size on some 186 triple carbed rails. Put lowly GTR CAST IRON TWIN OUT HEADERS ON INSTEAD OF PROPER TUBING HEADERS and got more toque and more power.

viewtopic.php?f=5&t=5554
Case 1: Holden Six, 202 cubic inch (1971 to 1980) . Head 9 port, engine is a miniture 230/250 with same bore spacing as FordS 144-250 I6's

Test one: Guy comes into Speed shop with an Eccon Rail with a 202 engine which won't past the 10.99 cut off for entry into the class. It has tube headers, triple SU 1.75" carbs, a worked head, 11.2:1 compression and HEI ignition. Dyno triggers 210 hp net at 4750 rpm, and torque peaks at the same 4750 rpm as 190 lb-ft. This shouldn't happen if the cam is sorted. Normally peak torque is at about a third this speed ( 3600 rpm). So the 308 degree high lift screemer cam is removed and replaced with a Waggot E3, a cam known for good results.

Test Two: the new cam is set at 22 thou lash, and the carbs get some ram tubes placed on them to smoothen the entry of air into the carbs. Dyno reads 222 hp at about 5700rpm, and now produces 205 lb-ft from over 5000rpm to 195 lb-ft at 3000 rpm. Something is not right with the exhast tunning. The torque peek should still be at a lower rpm.

Test Three: Six dyno runs are done with lesser valve clerances until 10 thou lash gives 236 hp at 5250 rpm. Over 219 lb-ft at 5000 rpm. Still looks to be an issue with the exhast system.

Test Four: Some bright spark grabs a set of old cast iron twin branch headers, used on the touring car special XU1 GTR. These on there own, with some tubing pipes running from them, loose 9 hphave shortened tubular pipes running off them for the dyno test. From 3000 to 4000 rpm, there is now an extra 20 lb-ft extra, but maximum power is only 227 hp at 5250 rpm.
Test Five: The dyno operator tries an old motor cycle trick...painting the tubes in acrylic paint, runs the engine at hi rpm, and cuts the tube where the paint stops burning off. Suddenly, during the last run, a mighty 254 hp @ 5250 rpm appears. At 2500 rpm, there is another 42 lb-ft there! The torque peek is now much lower at about 3800 rpm.

Now, do the sums. 202 cubic inches, times 5250 rpm, divided by some factor, gives 252 hp. What is it? 4208. At the start, it was only 4570. This makes the engine tunned to almost a "full-house, gas flowed, carb'd 300 degree + cammed motor". All this form a day on the dyno!


One thing you can do right away is weld up the combustion chambers.

Add 13 cc of metal, raise the cr with a 47 cc chamber. That will get you back more than 6% more power for everypoint you go upwards. Intake CFM of the closed chamber head is much better than the open chamber head. SEE http://victorylibrary.com/mopar/otto-c.htm

https://www.youtube.com/watch?v=wBrH6Jt9aKA

Its used on 351 C and Lima 2.3, Ohve head valve HSC/HSO 2.3 (LIKE THE ONE IN THE VIDEO.HINT HINT.) and Pinto 2.0 heads, since they are kind of detonation prone, and have some really poor flame front and mixture motion issues due to ports which have a lousy short turn radius. The 2v head is a semi closed chamber heart combustion chamber, sort of like the 2.3 HSC, its got some space to attempt to propigate swirl.
 
xrwagon":1lq80xxy said:
I’m playing devils advocate, so with the alloy head on a 200 are they having similar issues. .

the alloy head has much smaller inlet ports than a 2V head. its not a direct copy.

and alloy head has better exhausts flow

may have even bee designed for a 200ci -with meat to make the ports work on 250ci- when opened up - some one can chime in

and the benefit of 40 years of experience in what port sizes/shapes, combustion chambers work.

its all to with what revs your power is designed for :

as exctasy said - mismatch on the components (cam ,comp, ports,exhaust design/size, valves )and its a dog all round:

260 fpm (generally the notional velocity on a flow bench -where it all works for max power ) port velocity on a 2v 250 ci designed (for example) for 6000rpm equates to 7500-8000 when same head on a 200ci.

(6000rom was just an example - not sure what velocity a 2v head is designed for when on a 250)

and I think that's the ford 250ci 2v standard engine problem - from factory it had same cam and springs as the log head/precrossflow - so no real extra RPM in the engine as designed

what are you revving your 200 to ? I suspect its not 7500rpm :)


maybe you could get some z spar putty and fill in the inlet ports on your 2v to bring port velocity in line with your capacity and revs....
 
Nothing wrong with what you've done. It's just under cammmed, and under compressed. It'll take a 290 cam, with 470 lift, and 11.2:1 compression, a 4.11:1 pintara diff crown wheel and pinion, and then blow the pistons before giving flat 15 quarters with 90 mph tap speeds with that combo.


Meantime, Check for clutch slip.

Normally, a stouter combo blows the main seal, and does a "Gelignite Jack Murray 48 Ford V8 Grey Ghost Impersionation"...oil down creating clutch slip. The Borg Warner 3 sped has nice 2.95, 1.69, 1:1 ratios, and when a manual is dynoed, you'd expect just a head addition to drive the horsepower up from about 67 stock rear wheel hp to 103 hp, about 36 rear wheel hp. Then you look at bumping up the cam and compression, and dropping in the demon diff like Crosley has in his.

A good cam and compression bump up can make all the difference. The cam alone can give gave 14 extra rear wheel horsepower with just another 10 degree duration at lash, and another 25 thou lift at the valve. There is another 4.7 rwhp with 10.2:1 compression hike, one point up.


Unlike the Aussie 200 tall decks, the early short deck engine is restricted by a 250 style conrod to stroke ratio; the 7.803" 200 doesn't have the specific horspower per cubuc inch of the 9.38" deck engines.

In all 1971-1992 Fords, the little engine would just pull another 25% more revs to compensate for the lack of toque and power. The 3.3 would only be 9% down on power on the 4.1 anyway, as it carried more revs, maxiumum poweris at 4200 rpm, not 3600 rpm.


The little 200 won't pull the 25% extra revs the long rod 200 engine does over the 250. (5500 rpm verses 4500 rpm at max revs).

That means it needs a lot more cam aggression to get it moving. That's why Ford put the hotter cam in the 1985 EFI 4.1...the stock 256 degree cam used since the year dot on 200, 250, and 250 2v's wasn't able to elevate the 1982-1984 4.1 EFI into anthing more than a 16.9 second 1/4 mile plodder. The XF Spack 4.1 EFI doled out 16.3 quarters and another 5 km/h with its better cam. The car had a redline 300 rpm lower than the XE, yet with a bigger cam. The 1972 XA GS 250 2V did flat 16.9 second quarters, so did the 1982 4.1 S-pack EFI. That means that the 170 hp gross 250 2V was no more powerfull than the 149 hp net EFI XE 4.1. The cam alone gave 14 extra horspower.


Or remember the Big Valve Brock head option in the 4-speed manual 1985 VK Calais....on a Brock Commodore SS, 14.9 or even 14.4 second quarter miles, 237 km/h, but without the Wade 169 cam, and headers, just 16.3 second quarter miles, no different to the 1978 4 speed SLE 5.0 VB commodore, top whack down 47 km/h. Hp down to from 252 hp net at flywheel to about 169 -183 hp, a 43% power drop.

Some combos just do that.

Sam Blumstein at Chevy Offroad and Marine said it best...there are no wrong cam combinations, only wrong engine combinations.

The engine you have is like a 290 hp Gross Boss 302...it should do 14.5 second quarters, but if you slapped on a set of 8.9:1 compression open chamber 4v 351C heads and no longer had 10.7:1 compression, and derated the cam from a high lift 290 degree solid to a low lift 302 2V Cleveland 256 degree hydraulic cam, you'd go from the stock 330 flywheel net hp to about 207 hp net, a loss of 55%.


Undercammed, under compressed, you've lost the potential to gain the power in air flow the head can support.

I'd slap a Aussie version of the 274 cam Crosley uses in his 205 hp 200, and spike the compression up to the 10.5:1 or more Mustang Geezer uses.
 
Ive ordered a billet solid cam from Clive cams, 2V head will be shaved for 9.5.1, new faced solid lifters, Rollmaster or JP timing set, new valve springs, specs of the solid to follow, we changed our mind again. But its a mild solid, more designed for the wagon, weight, gearing than specific for the motor, so marry up the tow. Just had to bite the bullet, (that hurt .303 casing) will end up doing some things twice.
 
ok guys, all my bits are here and ready for install, the 2V head now achieves 9.8.1 comp and has a decent set of valve springs that will go to 515 lift, the new Clive billet solid cam is fairly mild, have new refaced lifters and the roll master timing set, al i have to do is remove the balancer tomorrow and i can start the install, I’m not that mechanically minded and haven’t changed a camshaft for many years, i hope i have the engine at TDC for starters, i removed the dissy today and it wasn’t pointing at number one for the rotor like i thought but piston was where it should be. I have a performance engine builder coming around to install the cam and degree it in, its ground on a 110 lobe centre, should this be advanced 4 degrees? I also got some hardened washers for the head bolts. I will leave the cam install up to my guru friend.
 
xrwagon":a594gh3g said:
ok guys, all my bits are here and ready for install, the 2V head now achieves 9.8.1 comp and has a decent set of valve springs that will go to 515 lift, the new Clive billet solid cam is fairly mild, have new refaced lifters and the roll master timing set, al i have to do is remove the balancer tomorrow and i can start the install, I’m not that mechanically minded and haven’t changed a camshaft for many years, i hope i have the engine at TDC for starters, i removed the dissy today and it wasn’t pointing at number one for the rotor like i thought but piston was where it should be. I have a performance engine builder coming around to install the cam and degree it in, its ground on a 110 lobe centre, should this be advanced 4 degrees? I also got some hardened washers for the head bolts. I will leave the cam install up to my guru friend.

Sounds like you might of been 180 degrees off if the distributor when you pulled it if it wasn't on number one, ie so wasn't on the compression stroke. Good luck on the cam install :nod:
 
Cam specs are last, i pulled the harmonic balancer off, timing cover, timing set in there of unknown mileage was very slack to say the least. I took the cam plate off and thought the cam would just slide out, i take it i am missing something, as far as dissy being 180 out, i am unsure, removing the balancer made sure that all got mucked up. Here are specs of cam 110 lobe centre solid cam, 214@50 423 lift. Nothing outrageous. Its called a Clive Cams 157 grind and its a brand new billet.
 
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