veedubdude Posted May 19, 2008 Report Share Posted May 19, 2008 (edited) Ive just been searching about on vagcat to see the differences between the heads of the 1.4 16V 75, and 100bhp, and the 1.6 16V 125bhp. Ive come across some interesting part number similarities, so just thought Id post up with quite a few posts being about cams recently! Whilst the 1.4 75bhp, and 1.4 100bhp use the same exhaust cams. The 1.4 100bhp uses an inlet cam not used on anything else, and the 1.6 125bhp uses an exhaust cam not used on anything else! All valve springs, inlet, and exhaust valves are the same! (Which brings me to assume the 1.4 75bhp are restricted to a 6K RPM redline (instead of 7k RPM on the 100bhp) because the aluminium bottom end may not be up to it, rather than the head) The cams on the 1.4 100bhp are supposed to be slightly wilder... and I can full well believe it if the 1.6 125bhp uses the same inlet as the 1.4 75bhp. So what I draw from this (someone else correct me if they see different) - is that using the 1.4 16V 100bhp head, on the 1.6 16V block is going to give the best combo of the later engines - steel block instead of aluminium, and nicer inlet cam with no VVT. (This is of course excluding the older polo 1.4 16V head which is a better set-up as has been discussed before... The valve springs in this head are also the same as the later blocks, but the cams both have different part numbers. How the cams compare to the later blocks I do not know for definite - but comparing my 1.4 16V 75bhp, against the 1.4 16V 100bhp(early polo AFH) the cams in the early head are pretty mean after about 4kRPM, just seems to take off! How they compare to the later 1.4 16V 100bhp cams I do not know, but suspect they would be very similar.)This may be of use to some of you, or no use at all, but there ya go! Just wanted to write it down somewhere as a reference to the 'how do I get the other 25bhp out of my 75bhp 1.4 to make it the 100bhp 1.4' lol ### EDIT: Just checked some of the part numbers on ETKA instead of vag-Cat (which is a copy of etka) and some of the cam part numbers are different - God knows why?!?! The inlet on the 1.4 75bhp is not the same as the inlet on the 1.6 125bhp. Ive deleted some of the info above to show this. Looking at the proper ETKA, there is actually very little cam swap over, and a hell of a lot of different cams considering they are the same engines ### Edited May 24, 2008 by veedubdude Quote Link to comment Share on other sites More sharing options...
Tigz™ Posted May 19, 2008 Report Share Posted May 19, 2008 What a great thread!where did you find this info?I did hear a few years back that the sports cams were more extreme, thats why the sport is hopeless lower down the rev range. I think I may try it on the Lupo. Are you going for it? Quote Link to comment Share on other sites More sharing options...
veedubdude Posted May 19, 2008 Author Report Share Posted May 19, 2008 (edited) I used vagcat.com, and with the different engine codes I just sifted through the part numbers to cross reference them!I dont know what to do at the moment! All I know is I need to rebuild my engine onto the lupo GTi block Ive got, because I now have no faith in the aluminium block! I was sure it would be the head which was the main weak link to higher revs, but obviously not!I dont want to spend the money on upgrading to the AUB (1.4 100bhp) head, because ideally I want to go onto the AFH head away from hydraulic tappets. I think the first step for me is to get the engine running and in on the GTi block, get it run-in, and then look at how I can adapt the AFH head on with new cams and vernier. Its all about the AFH! It looks so much nicer as well tbh! Think Im going to give mitch a PM now as he's the only guy Ive seen with the AFH head on the later block.If I where you I'd keep what you've got get it mapped and see how it runs - save the map, and then swap the heads and re-tune, see what the difference is! Then report back and let us all know which is better, lol. Then if the AUB head isnt as good, at least you can swap the other straight back over no problems!Ive just thought, all Ive heard about the heads being weak on the later models, Ive never actually seen a post on anyone's breaking?! Ive heard numbers of around 200bhp is about tops of what they'll take, but is there actually any proof of that, or is it speculation?! Edited May 19, 2008 by veedubdude Quote Link to comment Share on other sites More sharing options...
Blackrat Posted May 20, 2008 Report Share Posted May 20, 2008 haha thats quite a concoction of swopping cams eh ... would like to know what the 100hp inlet cam does on the gti Quote Link to comment Share on other sites More sharing options...
Tigz™ Posted May 20, 2008 Report Share Posted May 20, 2008 Fancy giving me a hand swapping them over and we'll find out? Quote Link to comment Share on other sites More sharing options...
simpo Posted May 20, 2008 Report Share Posted May 20, 2008 Your going to end up with two purple heads at this rate , do it though. I have access to a polo gti engine that im considering putting in when im 21 so the information could be very helpful. Quote Link to comment Share on other sites More sharing options...
Lee_ Posted May 20, 2008 Report Share Posted May 20, 2008 Very good info, would be very interesting to see the results of the 100bhp inlet cam on a GTi. Quote Link to comment Share on other sites More sharing options...
dougless Posted May 20, 2008 Report Share Posted May 20, 2008 This seems perfectly logical. VW have always used parts for one vehicle to develop another. The original Type 2 was developed from the Beetle (Type 1). It make sense to share parts around as much as possible. I think this is a great piece of detective work; I expect some people are going to have some fun with this knowledge. Quote Link to comment Share on other sites More sharing options...
veedubdude Posted May 20, 2008 Author Report Share Posted May 20, 2008 I wonder if just swapping the inlet on its own would make a bigger difference to swapping inlet and exhaust... ? I guess they're designed to work in pairs so should probably swap both over for the biggest improvement! Quote Link to comment Share on other sites More sharing options...
Blackrat Posted May 20, 2008 Report Share Posted May 20, 2008 I wonder if just swapping the inlet on its own would make a bigger difference to swapping inlet and exhaust... ? I guess they're designed to work in pairs so should probably swap both over for the biggest improvement!on the old skool 16v we used to cut the vernier section off an exhaust cam and use it as a inlet cam , the duration was different and there was an increase in performance ...you wouldnt need to swop both, but imo you would need to check the lift, if there is too much you gonna bend em valves Quote Link to comment Share on other sites More sharing options...
veedubdude Posted May 21, 2008 Author Report Share Posted May 21, 2008 So you reckon if the lift is ok, just swap the inlet cam? Quote Link to comment Share on other sites More sharing options...
veedubdude Posted May 21, 2008 Author Report Share Posted May 21, 2008 More interesting information! Ive just had information through from a guy in Germany who was running an AUB turbo, with ported head, standard pistons w/ decomp plate, and standard AUB head internals (1.4 16V 100bhp). It was running around about 250bhp, with no problems! I dont know how true the HP figure is, but the guy uses it for racing. I think its like the hillclimb events in this country the way he describes it.(The block was also the AUB block - aluminium with the water jacket around the whole piston, not seperated water jacket like the steel GTi block. So if the alu block can take that punishment, the GTi block (at a guess) can take a whole lot more)So, checking out the hydraulic rocker arm part numbers - the arm itself and the hydraulic equaliser are the same part numbers throughout the range of engines! Good times Quote Link to comment Share on other sites More sharing options...
vworks41 Posted May 21, 2008 Report Share Posted May 21, 2008 Great info!! whos guna be the first to give it ago then? Quote Link to comment Share on other sites More sharing options...
veedubdude Posted May 21, 2008 Author Report Share Posted May 21, 2008 Im in the process of purchasing some sport cams for the time being... And Im hoping to have the car at inters... Quote Link to comment Share on other sites More sharing options...
veedubdude Posted May 22, 2008 Author Report Share Posted May 22, 2008 Oh yeah just remembered! Another reason for the 75bhp over the 100bhp, is the fuel pressure. Unless I had a dodgy fuel pressure regulator before I swapped (which I dont believe as she was RR'd at 85bhp), the 75bhp engines runs at about 2.5bar, whilst the lupo GTi fuel rail, pressure regulator etc. I replaced it with ran at 3 bar. Quote Link to comment Share on other sites More sharing options...
Daz Smith Posted May 23, 2008 Report Share Posted May 23, 2008 (edited) I knew a guy that was into Fords and they used to do something like a 1.8 head on a 2.0 block or whichever way round it is!! Don't really know that much about it but sounds good what you've discovered!!!Daz Edited May 23, 2008 by Daz Smith Quote Link to comment Share on other sites More sharing options...
Niche Posted June 21, 2008 Report Share Posted June 21, 2008 What a great thread!I did hear a few years back that the sports cams were more extreme, thats why the sport is hopeless lower down the rev range.I wondered why they were hopeless in lower revs too. So this explains why some people say the 1.4 16V 75BHP feels nippier than the 1.4 16V 100BHP block. Quote Link to comment Share on other sites More sharing options...
Vside Posted August 2, 2008 Report Share Posted August 2, 2008 Im looking at getting the 16V 100hp but from what i read am thinking the 75hp ones better am I right? What one would others choose?? Quote Link to comment Share on other sites More sharing options...
Frankie Posted December 27, 2009 Report Share Posted December 27, 2009 (edited) . Edited December 27, 2009 by Frankie Quote Link to comment Share on other sites More sharing options...
Clairey Posted December 27, 2009 Report Share Posted December 27, 2009 I knew a guy that was into Fords and they used to do something like a 1.8 head on a 2.0 block or whichever way round it is!! Don't really know that much about it but sounds good what you've discovered!!!Dazyeh 1.8 head on the 2.0 block! the 1.8 engines are more revvy than the 2l the 2l block dont have as much grunt at the bottom end as the 1.8 does but more higher up where the 1.8 runs out! so the 1.8 would be more suited to quarter miles where as the 2l would be for 30-120 runs Quote Link to comment Share on other sites More sharing options...
MarkS Posted December 29, 2009 Report Share Posted December 29, 2009 Great thread Has anyone tried the sport inlet cam in a GTi yet? Quote Link to comment Share on other sites More sharing options...
Petar001 Posted November 17, 2011 Report Share Posted November 17, 2011 You can not put inlet cam from 100 or 75hp 1.4 engine because GTI has VVT that stand for Variable valve timingso this is not possible For sureBUt you can Put head from 1.4 16 100hp to GTI block with some modifications and you can get 250 as someone said because 100hp doesnt use VVTFor Gti there is only one option sport cams from Schrick and i think catcams has it too Quote Link to comment Share on other sites More sharing options...
Kam Racing Posted November 18, 2011 Report Share Posted November 18, 2011 We've just developed cams for N/A Gti models with CatCams which we believe should give gains of 7-8% based on the difference between these and standard ones. The blanks are all made so we're just waiting on the rolling road data from the tester for confirmation of the performance gains before putting them for sale.. Quote Link to comment Share on other sites More sharing options...
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