| ausmini https://ausmini.com/forums/ |
|
| 850 looking big bore https://ausmini.com/forums/viewtopic.php?f=2&t=91628 |
Page 1 of 1 |
| Author: | Phil 850 [ Sun Jan 24, 2016 10:30 am ] |
| Post subject: | 850 looking big bore |
Is it feasible to fit a small bore head on a big bore (1100S) to make the engine "look" like an original 850. I realise it would need chamber, valve and port work, but can you still get the original 1275 power ? |
|
| Author: | drmini in aust [ Sun Jan 24, 2016 11:42 am ] |
| Post subject: | Re: 850 looking big bore |
To use a smallbore head on a 1275 gasket, some water holes in the head need plugging & redrilling. See GR's project 68mm story on his website. I have just done this to a 202 head for a 68mm bore 998. Yes it can be ported to flow like a stock 940 head. (Edit) Why do this?? 
|
|
| Author: | Phil 850 [ Sun Jan 24, 2016 12:01 pm ] |
| Post subject: | Re: 850 looking big bore |
Why The most obvious thing about a big bore is the position of the thermostat housing. If I have a small bore head on the big bore in my 850 it will "look" more original. At a quick look in the engine bay it will look to the untrained eye like an original 850. |
|
| Author: | gtogreen1969 [ Sun Jan 24, 2016 12:09 pm ] |
| Post subject: | Re: 850 looking big bore |
Sleeper 850 |
|
| Author: | Phil 850 [ Sun Jan 24, 2016 12:29 pm ] |
| Post subject: | Re: 850 looking big bore |
gtogreen1969 wrote: Sleeper 850 The pro's will quickly look further and discover what's going on, but the uninitiated might not 
|
|
| Author: | drmini in aust [ Sun Jan 24, 2016 12:54 pm ] |
| Post subject: | Re: 850 looking big bore |
Make sure the head isn't decked much, these old smallbore heads are all corroded inside and the deck is much thinner than a 1275 one. |
|
| Author: | TK [ Sun Jan 24, 2016 1:56 pm ] |
| Post subject: | Re: 850 looking big bore |
You going to run a single HS2? I'd be more inclined to keep the bonnet closed and run a real free flowing 1275. |
|
| Author: | drmini in aust [ Sun Jan 24, 2016 2:08 pm ] |
| Post subject: | Re: 850 looking big bore |
1275 with an HS2 is a waste of time,IMO. But it'll climb hills good. 
|
|
| Author: | gtogreen1969 [ Sun Jan 24, 2016 2:27 pm ] |
| Post subject: | Re: 850 looking big bore |
I would go Twin HS2's and a Sticker on the rocker cover that reads "Sports M 850" |
|
| Author: | drmini in aust [ Sun Jan 24, 2016 2:35 pm ] |
| Post subject: | Re: 850 looking big bore |
I put a 1098 crank & pistons in a Sports 850 back in the 60s. With stock head & cam it didn't rev hard, but boy it had some torque. Good sleeper. |
|
| Author: | TK [ Sun Jan 24, 2016 8:17 pm ] |
| Post subject: | Re: 850 looking big bore |
My first car was a 72 Clubman with a tired 1098. The car was 100% stock. I was able to pick up a reco 1330cc that replaced the original. So I was running it with the original carb, that is a HS2 and exhaust. After about three months I saved up some money and then put on a set of Sprite SUs and extractor exhaust. It had twice the power!!!!! |
|
| Author: | PDJ [ Mon Jan 25, 2016 10:24 pm ] |
| Post subject: | Re: 850 looking big bore |
So you think that the thermostat position is more noticeable than a big carby or an engine number starting with a 12? Does seem a bit crazy to me . It'd definitely be different. |
|
| Author: | TK [ Mon Jan 25, 2016 10:58 pm ] |
| Post subject: | Re: 850 looking big bore |
maybe it will start with a 9? 
|
|
| Author: | Phil 850 [ Tue Jan 26, 2016 9:25 am ] |
| Post subject: | Re: 850 looking big bore |
Well, I've gone to the trouble of replacing my rod change box with a 4 synchro box and 850 diff so that I will have a Magic Wand gear lever so the interior looks more original . Was wondering what I could do in the engine bay to make it more 850ish. I'm not after total originality, just a bit more like an 850. It will still have the 1-3/4" SU and extractors (like a souped up 850) ! |
|
| Author: | min13k [ Wed Jan 27, 2016 12:04 pm ] |
| Post subject: | Re: 850 looking big bore |
just go with the full bore 1275 |
|
| Page 1 of 1 | All times are UTC + 10 hours |
| Powered by phpBB® Forum Software © phpBB Group http://www.phpbb.com/ |
|