guy
Part of things
Posts: 352
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Jul 11, 2006 13:22:55 GMT
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Well i have just got a head for my 1300 xflow and i want to get the most from it?
What are the easiest ways of gaing extra horses from my head??
I don't really have any serious tools so larger valves etc are out of the question??
Thanks
Guy
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Mk1 Escort slowly rusting into nothing! But safely stored in a dry garage. Mk2 Golf, Low n' Loud
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Jul 11, 2006 13:24:33 GMT
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is it good for unleaded? is it the GT/ghia head?
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guy
Part of things
Posts: 352
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Jul 11, 2006 13:27:16 GMT
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I believe its from 1600, the valves are 38.2 and 34mm. Larger exhaust valves than the Gt i think?
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Mk1 Escort slowly rusting into nothing! But safely stored in a dry garage. Mk2 Golf, Low n' Loud
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Jul 11, 2006 13:37:10 GMT
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Buy Vizard's book. *n
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Top grammar tips! Bought = purchased. Brought = relocated Lose = misplace/opposite of win. Loose = your mum
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Jul 11, 2006 13:37:48 GMT
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couldnt tell you tbh mate, easiest thing to do is match the ports, get the dremel out and grind them out so they give a smooth flow from manifolds to head, always a good idea to polish the outlet too, wouldnt bother with polishing the inlet as it usually makes it worse.
give it a skim too.
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Jul 11, 2006 14:08:02 GMT
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Buy Vizard's book. *n All hail the god of tuning. Polish stuff. Doesn't polishing the inlet smooth the airflow thereby reducing the quality of the air/fuel mixture?...or am I misguided!
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Peugeot 307sw - Suzuki SV650S - MX5.
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SkoCan
Posted a lot
Quando omni flunkus, mortati
Posts: 1,916
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Jul 11, 2006 14:13:59 GMT
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No, you've got it right. Just as Seventynine said. ;D
Polishing the intake reduces the turbulence in the flow, lowering the ability to keep the fuel in suspension.
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Jul 11, 2006 15:26:55 GMT
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No it doesnt Urban Myth The theory is sound but the difference is imeasurable in practice on a Calibrated engine dyno Zero difference in power, economy or anything else on the same engine same conditions with just the surface finish being different Been there done it Smooth ports are easier to do anyway ;D
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SkoCan
Posted a lot
Quando omni flunkus, mortati
Posts: 1,916
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Jul 11, 2006 15:47:14 GMT
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oh I'll take a point for correct theory then. What's my score now? ;D
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slater
Club Retro Rides Member
Posts: 6,390
Club RR Member Number: 78
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So tell me about heads??slater
@slater
Club Retro Rides Member 78
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Jul 11, 2006 17:02:22 GMT
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Its all theory.
Basicly the biggest tip i can give you is to remove some meterial from the top of the port and from around the valve guide boss. don't remove meterial fron the bottom of the port or waste your time polishing. Make sure its all smooth with no lumps and bumps too.
Its the shape that relly makes the differance.
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Jul 11, 2006 17:06:59 GMT
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I've seen stuff reported in a magazine where they took 6 or 8 top head modifiers / engine builders and asked them their experiances on various head mods (polishing ports being one of them) and reproduced the results in the mag. It was interesting reading. Even the professionals with 20-30 years in the trade building race and fast street motors disagree with each other on lots of (usually minor, sometime major) points. Some claimed there was a peformance decrease through polishing the inlet port. Nobody claimed a reduction through polishing the exhaust. Most said they did it because customers expected to see it done and they were paying after all... A couple claimed minor improvements due to improved heat retention and reduced coking of the port over time. Same for chamber polishing, although all agreed ceramic TBC technology was the way to go if heat management is your aim. I believe Vizard is of the opinion not to polish anything, and he's never sold me false yet You'd need to double check in his book (plug, plug) rifled hatching is apparently the way to maintain inlet port fuel suspension. Far beyond the capabilities of you or I with a dremel though
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1941 Wolseley Not Rod - 1956 Humber Hawk - 1957 Daimler Conquest - 1966 Buick LeSabre - 1968 Plymouth Sport Fury - 1968 Ford Galaxie - 1969 Ford Country Squire - 1969 Mercury Marquis - 1970 Morris Minor - 1970 Buick Skylark - 1970 Ford Galaxie - 1971 Ford Galaxie - 1976 Continental Mark IV - 1976 Ford Capri - 1994 Ford Fiesta
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guy
Part of things
Posts: 352
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Jul 11, 2006 17:15:58 GMT
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I read somewhere that even the rifled hatching doesnt do much, the theory is there but in practice it makes very little difference?? I may be wrong though i will try and find the arcticle on the web??
Thanks everyone, will vizards mini book help me because i have got that somewhere, i cant really afford a new book at the moment!!
Guy
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Mk1 Escort slowly rusting into nothing! But safely stored in a dry garage. Mk2 Golf, Low n' Loud
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guy
Part of things
Posts: 352
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Jul 11, 2006 17:36:02 GMT
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What was the spec of your 1380?? Do you know how much power it produced???
Guy
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Mk1 Escort slowly rusting into nothing! But safely stored in a dry garage. Mk2 Golf, Low n' Loud
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slater
Club Retro Rides Member
Posts: 6,390
Club RR Member Number: 78
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So tell me about heads??slater
@slater
Club Retro Rides Member 78
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Jul 11, 2006 17:43:17 GMT
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it runs a 234cam with a DGAV webber and GT manifold, Head was GT unit with stock GT valves. Bottom end was all standard parts but it was fully blueprinted to race spec. I never got it rolling roaded as i wanted to get twin 40s on it but never had the chance.
The car liked to rev alot! so would have benefitted greatly from the carbs and a 244cam i think.
Its going in my dads anglia for a bit now i think whilest he builds a lotus motor for it ;D
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guy
Part of things
Posts: 352
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Jul 11, 2006 17:48:49 GMT
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If you ever feel like selling it, i would give it a good home!
Guy
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Mk1 Escort slowly rusting into nothing! But safely stored in a dry garage. Mk2 Golf, Low n' Loud
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Jul 12, 2006 12:22:06 GMT
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Jul 12, 2006 15:36:44 GMT
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This is interesting! I got given a Sprint head today (minus valves unfortunately but replete with rocker assembly).
Inspired, I think I'm going to take my steel rule to it and see if it's flat. I figure all the valve seats should be nicely work harderened after it's life, so provided it's crack free, flat and otherwise free of damage I may get the dremel out.
I've got a few of Vizard's books, they really are ace. Got quite a few others too ;D
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guy
Part of things
Posts: 352
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Jul 12, 2006 15:40:31 GMT
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*Adds dremel and books to shopping list!
*looks into possibility of robbing bank
*but walks off to find the job paper!
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Mk1 Escort slowly rusting into nothing! But safely stored in a dry garage. Mk2 Golf, Low n' Loud
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Jul 12, 2006 20:28:20 GMT
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Amazed the old chesnut about 1100 pistons into 1300's and 1300 pistons into 1600's has not cropped up yet!
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