2013/09/03 20:43:17
Cabbageman
Hi guys an gals.
I'm new to forum so bear with me
I have recently built up a 1700 xflow with some good gear 711m block forged accralites modified to give 10.7 to 1 static compression kent 234 cam kit all fully balanced,ported flat head with standed valves,twin throttle bodies from jenvey with omex ecu wasted spark ignition all in a mk 2 cortina. Recently had it tuned on dyno and made a touch over 100 hp at the wheels.
I was hoping for a bit more than that an noticed that at about 5800 rpm the cam run out of puff.
I have decided to go for a new cam profile and would ask for some advice, i am thinking of a kent 244 butt think this may still be a bit small for my intentions just wondering if anyone has used the kent 254 with good results
Your thoughts much appreciated
2013/09/04 08:29:58
Matt75
What type of driving do you do in the car?  
 
This will determine the best cam to suit your needs.  No point getting a monster cam making power above 4k when it's your daily driver.
 
Cheers,
 
Matt
2013/09/04 16:31:09
Cabbageman
Na not daily driver does get driven on road but usually to an event, hill climb circuit track day ect.it is nice to drive but just feel as though there is more to get out of the little beast.
2013/09/07 09:25:39
Smcka
I had basically the same spec motor on 45's with a 234 cam and again, no go after 5,800 (too bad Kent advertise them good to 7,000+/-). Mine made 101 at the wheels.
I would definitely go to the 244 cam at a minimum. I didn't look at the 254 at the time so not sure on that.
 
The limit will be revs; I buzzed mine to 7,000 with 6,500 regular limit but the pistons are the deciding factor on these as they are so heavy. As you have forged then you can probably do 7,000 constant (assuming the motor has been built to take that) so maybe 254 is the go.
 
I'd get on the UK forums, they tend to go sicker in cam than us and if you believe their figures of 180Hp for a street motor then they should be using a bigger cam than us.
 
I've also been advised that Piper do a good grind so maybe look at their offerings as a comparison.
2013/12/04 07:22:33
Muzza52
What distributor are you running ?
Is it an original unmolested unit from the 70s or 80s ?
Leaded fuel burned at a much slower rate than todays unleaded fuels.
So, the old dizzys advance curve (rate of advance) and amount of advance are too great for unleaded.
An engine will not develop full power as a result (i.e. quite a lot of power is "lost") when running an original distributor.
This is aside from the "pinking" issue.
I have the dizzys "regraphed" to suit the cam and fuel. Invariably, the vacuum advance is disconnected as it is just not needed.
I use Performance Ignition Services here in Melbourne... not sure where you are or if there are other specialist guys in other cities. 
With Performance Ignition Services, I advise them what cam and fuel I will be using and they set the dizzy up accordingly.
Otherwise, any of the new electronic distributors made for unleaded would suit.
 
This may not be your issue, but it is generally overlooked.
Have seen 10% to 15% increases on the engine dyno just by swapping out to a regraphed dizzy.
That was with 351 and 250 motors, but the issue would be the same for 1600xflows or the 2l OHC.
2013/12/14 07:22:40
hendo
I have only just seen this post, so you may have sorted the issue but I think the biggest restriction is the size of the valves and chambers. I know you said you had them ported but that only suits the valve thats in there at the time. I had two engines with the same spec block and cams, one had a superflow head (Hoxton park Sydney) and the other a sureflow (Sydney) the super flow had larger valves and the drive difference was very noticeable, both where very good and made the engine breath better. on the down side, because the area behind the valve was larger, at low revs if you wide opened the throttle the air flow almost stalls, so you have to get used to that when driving in traffic. 

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