hi guys, i will start to build my pinto engine 2.0 from a mk3 cortina, it was standard, but will be rebored and i will use accralite forged pistons, will work the head, a good exhaust and first will a install a 38 dgav.
i like the piper 285 cams, but in the future, i will make it injection with jenvey bodies, my question is, the piper 285 will push fine with the jenvey bodies? what power should i have?
285 will be just fine with the bodies.
as for power, so much depends on compression ( note the accralites wont give you more, you need to skim the head and block to raise compression) and how good you head is, but its not unreasonable to have in the region of 150bhp IF everything else is correct
I just had 150 Bhp with IDF, should be little more with side draught. But you need correct head work.
BP285 will not work with 38DGAS. I can only recommend not to use 38DGAS in any combination unless all out racing.
i think the 285 with the jenvey bodies will work fine, i will work my head and skim the block ofc!
hi onyd, can you give a more detailed reason behind this please ?Originally Posted by onyd
i trust your statement but i am sure a lot of people use this combination (285 is a popular cam - or used to be) and its always good to hear your experience
i think its rather like when a say an HT1 is not a road cam, it isnt, but people do drive on the road with that cam, doesnt mean it actually works as a road camhi onyd, can you give a more detailed reason behind this please ?
i trust your statement but i am sure a lot of people use this combination (285 is a popular cam - or used to be) and its always good to hear your experience
i think what he really means is low speed carburation particulary during progression will be rubbish, it will work once the revs are up, but at lower speeds fr30, 134 are much much better profiles and you will probably get nearly as much power and an engine will will work really well throughout the rev range
BP285 cam should work just fine with a 38DGAS carb provided you adapt it for a 2 litre engine.
Weber used to have a suitable 38DGAS for the Pinto, partno. 1893000.
Fastroadcars sell a 38DGMS for a Pinto, see
http://www.fastroadcars.co.uk/store/...product_id=589
think that the dgas was a typo , originator said dgav.
There is no 38 DGAV so assume it's a 38DGAS, or a 32/36 DGAV but that's a bigger typo ...
i want to build with the 38, and put bodies in the future...
Believe me, 38DGAS is really silly on the road. It has been sold by Weber as a fast road replacement but it's totally old school tuning. I've also been using this carb for years. You loose all the nice progression of the 32/36DGAV and you need a very high tuned engine before the standard DGAV is out of flow. And if you do run out of flow, in worse case bore first choke 1 mm extra en the second choke 2 mm extra. This carb wil flow at least as much as the 38 DGAV and still road drivable like standard car. BTW, if you feel you need to "bore" the chokes, start with second step first because this will have little to no influence on normal driving and jetting.
I'm no longer willing to go into any more details, also don't need never tested positive results, the BP285 has to much valve lift at TDC. It will also make less power everywhere, unless you got a serious build head and your RPM target is always 3500 RPM and up. I know exact how a BP285 profile looks like and same for BP134. I not only work on Ford engine (as a matter of facts, I seldom work on Ford engines these day) but see the same results in all engine I have to tackle.
You ask advise, I give advice, do whatever you feel right but think about, it does cost us a lot of time and money to find out what does work or not, take your cake and eat it, it's free. I hope you got the picture. Please note, I've done what you are trying and failed or at least, we found a better option. Dyno tested and not only on Pinto. I wish I could fix all my problems this way by just asking on a forum. Problem is a lot of forums and lot of written books are full of mistakes. Even if you can proof it's wrong it's still right.
Dirk,
you have me puzzled here ...
First you say you don't recommend the 38DGAS unless all out racing.
But the 38 DGAS is not unlike the 32/36 DGAV just with 2 similar venturis (27 mm) and 38 mm throttles.
How can you recommend that carb for all out racing???
If you have a light foot then yes the progression of the DGAV is nice but the DGAS synchro-opening of the throttles is really suited to a cam with more poke (lift). We've been using the DGAS with good results for years even with a RL2 cam in the old days. Just change the air idle jets for use with a 2 litre engine.
Looking at the (current) Piper BP285 it is one step more "radical" than a std cam.
See list below from Piper website.
Yes it has more lift at TDC than a 134 cam but well, any cam will have more lift at TDC as a 134 cam!
And the latter is known as a "caravan-cam" ...
Timing of the 134 cam is 23/63 63/23 (266 degrees) with an advertised lift of 12.2 mm.
Timing of the 285 cam is 27/63 73/37 (270 / 290 degrees) with a lift of 11.8 mm.
So lift at TDC will not be that much higher wrt to the 134.
If you claim the 285 cam will need a well modified head and has no real power under 3500 rpm then I am sorry but you must have been doing something wrong here, or are considering another cam instead of the 285.
Grtz, Leon.
Forgot Piper cam spec list
I was saying the 38DGAS is good for racing only and this in engine running over 3500 RPM. I was not saying you where using BP285 in a race engine. The reason the DGAS is worse as 32/36 is because as you will no longer have progression and second, the full load valve is not working anymore as it should. So the first part of the running (road running we where talking about) is missing all of the advances of the 32/36. Second, the 38DGAS is not flowing much more air as the 32/36 in standard form and in most engine you will not even need more flow. And if you feel you do, just bore the original 32/36.
I've been using and testing both carbs, I do know them and keep telling 32/36 is the carb to go for.
BTW all nice text on this Piper cataloog as usual. The BP285 is advertised 270° inlet and 290° exhaust. BP135 is 266°. Believe me or not but the BP285 inlet profile is EXACT the same as the BP285 in my measures. The exhaust profile looks the same but made longer and sadly for a single carb setup little to much lift at TDC. So please all, stop discussions if you have never measured these profiles. Do you really want his guy buy second best?
i dont want any discussions, sorry guys, i just want to make a good injection engine for the road, no race, rally or nothing like that, i really like the 285, i will put the 38 because its new, and in the future go with jenvey burton kit for pinto... the 285 with the jenvey will work fine i guess?
yes it will, but you know you will need a programmable ecu to use them?
In the case of throttle bodies, I would also go for the BP285. That's a complete different situation compared to the 38DGAS story.
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