Parko762 3 Posted July 22, 2019 After some info. Looking at building a solid street 4.1 carbie fed and curious as to the best cylinder head to use eg c1, c2 or other, i have a c1 casting and a c2 and intend larger valves and nessicary port work so with this in mind will it make any difference which i start with? Not after a specific power more just a very solid amount of torque. Any info would be appreciated as i cant seem to find a whole lot of info on the old bangers. Share this post Link to post Share on other sites
deankxf 20,231 Posted July 22, 2019 @ando76 is the expert on these things, the head mob i used knew what each was and had a preference for one or the other, but i cannot remember which what or why. Share this post Link to post Share on other sites
slydog 7,873 Posted July 24, 2019 Theres no best head just best for combination. In my finding using a good porter is more important as you get what you pay for there. Good porter can make any head work. But for the sake of it...I have used both on mine and both get extreme chamber mods to work. Small chambers with compression and small cams are rattlers. So with that in mind and not knowing the rest of the combo (small hyd cam,2 barrel carb extractors and maybe a ignition?) I would choose the C1. Share this post Link to post Share on other sites
Parko762 3 Posted July 24, 2019 I dont have a setup in mind i will research that at a later date its just i have 2 running engines and just at intend to use the one with the less ideal head as the one to get it registered and driving while i do the nessicary work and preparation to the second. But the basic idea will be a camtech CT142 517 and nessicary work to match or perhaps a custom turbo efi setup unsure yet just want something torquey and yet plenty of punch on the open road. Share this post Link to post Share on other sites
gerg 10,871 Posted July 24, 2019 I have very limited knowledge on these but I do know that somewhere along the XF range, possibly when they went unleaded, there was an issue with the combustion chamber design, in that a swirl wing cast into the chamber was found to be a hot spot that caused detonation. The fix was to remove the head and mill this lump of alloy flat. Dropped compression a bit but that was the known cure in the day. Sent from my CPH1903 using Tapatalk Share this post Link to post Share on other sites
deankxf 20,231 Posted July 25, 2019 1 hour ago, gerg said: I have very limited knowledge on these but I do know that somewhere along the XF range, possibly when they went unleaded, there was an issue with the combustion chamber design, in that a swirl wing cast into the chamber was found to be a hot spot that caused detonation. The fix was to remove the head and mill this lump of alloy flat. Dropped compression a bit but that was the known cure in the day. Sent from my CPH1903 using Tapatalk My head that was done up had that removed by the CNC porting program the head mob had i can't remember the casting number, but it was on a 1987 carby XF 1 gerg reacted to this Share this post Link to post Share on other sites
gerg 10,871 Posted July 25, 2019 My head that was done up had that removed by the CNC porting program the head mob had i can't remember the casting number, but it was on a 1987 carby XF Yeah that makes sense, the EFI head had a plain footy-shaped chamber without the wing, and came in at 8.89 compression. Carby ones were around 9.1 or 9.2, not sure what they were after milling that lump off, probably below 9.Sent from my CPH1903 using Tapatalk Share this post Link to post Share on other sites
deankxf 20,231 Posted July 25, 2019 1 hour ago, gerg said: Carby ones were around 9.1 or 9.2, not sure what they were after milling that lump off, probably below 9. mine had flat tops.. poor choice on My part(didnt choose a big enough cam.) and was around 11:1 i don't think it was zero decked, but the block was surfaced as was the head. 1 gerg reacted to this Share this post Link to post Share on other sites
slydog 7,873 Posted July 27, 2019 There was the biggest problem with peoples understanding of the long stroke xflow from days gone.Cyl pressure spikes are extreme and small cams with big comp make em rattle but the fix was camshaft design not the cyl head. 1 deankxf reacted to this Share this post Link to post Share on other sites
ando76 4,354 Posted August 2, 2019 The camtech you have chosen is a nice 218@.050 with .510 lift and a stock 110 lobe sep. Either the c1 or c2 will work just fine. A good seat cut and some minor bowl works will make it sweet. I put together a similar combo for a customer in Ipswich but it was slightly bigger at 240@.050 and .510 and solid (tighe 140T). Because of the bigger duration and overlap I was able to give it 11.7:1 Comp and it loves life. It's a 2 barrel deal with ultraflow manifold and 500 Holley. Made 198rwhp on Zok's performance's dyno and a big flat torque line. Both the c1&c2 have a sharp point where the intake and exhaust swirls meet in the chamber. Rolling that over reduces the chances of detonation. Good luck with the build. 1 deankxf reacted to this Share this post Link to post Share on other sites
Parko762 3 Posted August 2, 2019 Thanks for the advise fellas, that build will be a while away while i cut the rust out of the old girl no point building an engine till i can put it in the darn thing... 2 ando76 and deankxf reacted to this Share this post Link to post Share on other sites