Jump to content

Kent Fr32 Or Fr33


Guest vacinc

Recommended Posts

Guest vacinc

Standard pinto, 45"s, RH 4 branch, was going to buy a head ( cant Justifie the price )

so what do i go for fr32, 2500 to 7000 or fr33, 3000 to 7500 , rally design seem to be the cheapest

any feed back would be app

Link to comment
Share on other sites

Guest STEVE OXON

same as me,standard pinto .45s 4branch with lagging. i have a spare injection head being suitable for unleaded.i have started polishing/tarting head up and have an fr32.which would be much more tractable i feel than something which only pulls from 3k.and will youre bottom end take it........... i mean how many miles has it done/will it take the extra 15bhp supposedly got from the cam.

hth

steve

Link to comment
Share on other sites

Standard valves won't benefit from the extra lift, just move the available power further up the rev range.

Standard inlet valve is 42. 1 when the valve diameter is y (in this case 42.1mm) then no further flow is achieved after the valve has reached x when x = 1/4 y ( in this case 10.525mm at the seat).

So when you pick the cam look at the lift as well as the duration, also with the higher lift cam check that you don't need to do head mods to fit.

Link to comment
Share on other sites

Guest salty_monk

I Have the FR32 on a standard head, works very well. I would say the 33 is prob overkill unless you have a big valve head & strengthened/balanced bottom end.

 

Dan :)

Link to comment
Share on other sites

Guest vacinc
I Have the FR32 on a standard head, works very well. I would say the 33 is prob overkill unless you have a big valve head & strengthened/balanced bottom end.

 

Dan :)

so a FR32 on a standard head, it is then. did you use a verner pully ?
Link to comment
Share on other sites

I've just put an RL 31 cam on my 2.1 pinto....

 

The reason I chose this was that it kicks in at lower revs than the FR range

 

will let you know later this week what the horsey power and drivability is like

 

cheers

 

Chris

Link to comment
Share on other sites

Guest salty_monk

Yes, no point in having a high lift Cam without one. Nigel had a good internet source for them or sometimes they come up on Ebay.

 

Dan :)

Link to comment
Share on other sites

Guest Stevieshood

Personally, I would go for the FR33 (or poss RL31), because you already have a 4 branch manifold and twin 45 DCOEs.

 

Although big valves are the way to go, you could easily port the standard head to get rid of the restrictive valve throats, exhaust ports, and valve seat recesses for not much money (just a high speed die-grinder, a few carbide bits, and some patience!). You will see between 150-160bhp and it works well with the standard bottom end up to 7300-7500rpm. All the DIY info you need can be found in "How To Power Tune Ford SOHC and Sierra Cosworth DOHC Engines for Road and Track" by Des Hamill.

 

Indeed, peak flow is achieved when the "valve lift curtain area" equals the "valve annulus area", which is about 1/4 of the valve diameter (actually its the inner seat diameter and valve stem diameter that need to be used, so in fact peak flow occurs ~9.7mm mean lift. However, due to the cam profile constraints, the peak valve lift has to go some way beyond this to ensure that the maximum area under the lift-duration/time graph is achieved.

 

I've done something pretty similar with my "205 block" engine, except I'm planning to retain the injection manifold, ditch the airflow meter, and use a Megasquirt ECU. Some calcs seem to suggest this will be ok up to my target bhp.

 

At the end of the day, its up to you what you want to achieve as a long term goal.

Link to comment
Share on other sites

Guest robin

I've got an injection engine running on bike carbs with an FR33. It goes like stink and it's not even been setup on a rolling road yet! The downside is poor low speed driving and the idle speed has to be increased. You just end up driving it as though it's a motorbike engine, keep the rev's up and it's fine. B)

Robin.

Link to comment
Share on other sites

I am a big fan of torque and whilst revs sound nice and defer gear changes, its the low down torque thats pushes you forward, the lower down you hit peak torque and the longer and flater the torque curves is the quicker your car is in the real world.

With light cars like ours you can afford to be a bit more cammy but don't go silly.

At a recent auto jumble there was a serious head and cam set up that gave 166bhp, a full working by Chris of CTM, wasted stem big valves, fully ported head and matched inlet and exhuast with twin 45's. That lot was 750 second hand.

With respect, Stevieshood, a bit of patience and a die grinder will be good for 10bhp extra.

Link to comment
Share on other sites

Guys,

 

My pinto was fully recon'd, stage 2 (injected head fully ported, big inlet valves, FR32, vernier cam, twin 40s with 36 mm chokes, & lightened & balanced.

It was well set up on a respected rolling road & put out 136bhp.

The head must have contributed 10bhp of that, so dont really expect much more than 125 with a standard head (no matter how much you polish it) even with 45s which will still need 36 mm chokes.

 

With that set up I wish Id gone for the FR33...the hood is pretty light & doesnt need too much torque.

But with a standard head, Id stick to the FR32, its still a huge improvement on anything Ford plonked in a Pinto.

 

Sorry to be a misery, but 150-160 will take serious money, replacment rods & bolts, a head with bigger inlet & exhaust valves, & a better exhaust than RHE's.

 

Dont worry, 125-135 will still be heaps of fun. :D

Bob

Link to comment
Share on other sites

Guest Stevieshood
With respect, Stevieshood, a bit of patience and a die grinder will be good for 10bhp extra.

 

Maybe, but I've seen several Pinto engines on standard valves, twin 40s, and an FR33 making 150bhp. Its nearly always in the quality of work/set up, and I'm sure that fuel injection and proper mapped ignition gets rid of most of the poor low speed torque, and gives a bit more peak power.

 

I will never understand why people spend so much money on their engine and then control the vital bits with technology from the 19th century. :wacko:

Link to comment
Share on other sites

Well folks

 

just back from the engine tuners at motorscope in Northallerton.

 

They have just spent an absolute fortune on a new set of rollers and are spot on

 

the figures on a 2.1 pinto , with a stage 2 head , RL31 cam and twin 40 delloto's with 34mm chokes came out as follows

 

Torque - 160lb.ft @5000 revs

 

Power at the fly wheel - 182bhp @ 6,400 revs :D :D

 

Power at the wheels 137.4 bhp @6,400 revs :D :D

 

I have still not got the grin off my face from the feeling that a 180bhp engine gives....

 

It can be summed up in one word

 

WOW!!!!!! D :D

Link to comment
Share on other sites

Guest old_timbo

Assuming that the power was measured at the rear wheels, that's a lot of power loss through the transmission! I recon it should be around 17% i.e. flywheel figure is more likely around 165BHP. How was the transmission loss estimated?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...