The Hillman & Chrysler Avenger Forum

Avenger Related => Technical => Topic started by: old white 73 on August 16, 2014, 10:32:38 AM

Title: motor rebuild
Post by: old white 73 on August 16, 2014, 10:32:38 AM
hi, i have a spare worn out 1500  here i want to rebuild & get some more torque from, not worried about top end power so much.
the block i've got has been bored out & with the amount of wear it's got it'll be over any avenger piston size once bores are tidied up & the rods are too corroded to use.
are there any other piston/rod combinations that can be used?i've heard a rumour that a ford crank can be made to fit?
is it viable to bore block out to 1600?
there'll be a cam change, twin carbs & manifolds, electronic ignition & a sierra 5 speed ( sitting in shed waiting to get extention housing shortened) any adive/ideas greatly appreciated, thanks
Title: Re: motor rebuild
Post by: JoKer on August 16, 2014, 05:22:53 PM
not sure what's wrong with the avenger crank?

Richrds 1500 is pretty peppy, bigger is not always better
Title: Re: motor rebuild
Post by: oldschool on August 16, 2014, 07:19:09 PM
The crank may have rusty journals making a grind necessary?
The rods are cast iron so will just have surface rust.
The 1500 and 1600 block are the same...just a 1.2mm bore increase from 1500 to 1600 so no problem to fit std or oversize 1600 pistons.
Title: Re: motor rebuild
Post by: old white 73 on August 16, 2014, 07:48:19 PM
crankshaft is good, main & big end bearings are still good enough to reuse if we want to, need suitable pistons to fill the holes once the bores tidied up, need rods too-old rods are stuffed though, badly corroded- engines been in a car parked under a shelter belt maybe 20 years.
Title: Re: motor rebuild
Post by: old white 73 on August 16, 2014, 08:27:09 PM
with different strokes though 1600 pistons wont go high enough?
Title: Re: motor rebuild
Post by: oldschool on August 16, 2014, 09:29:40 PM
Quote from: old white 73 on August 16, 2014, 08:27:09 PM
with different strokes though 1600 pistons wont go high enough?

Not sure...talk to Richard, I think he used 1600 pistons in his 1500...maybe had the block planed?
All Avenger rods are the same length.
Title: Re: motor rebuild
Post by: old white 73 on August 17, 2014, 12:40:50 PM
have found a 1300 crank in another motor, should be able to put that in 1500 block & bore it to suit 16oo pistons
Title: Re: motor rebuild
Post by: avenga on August 19, 2014, 09:48:12 AM
Quote from: JoKer on August 16, 2014, 05:22:53 PM
not sure what's wrong with the avenger crank?

Richrds 1500 is pretty peppy, bigger is not always better
Quote from: oldschool on August 16, 2014, 09:29:40 PM
Not sure...talk to Richard, I think he used 1600 pistons in his 1500...maybe had the block planed?
All Avenger rods are the same length.


My 1500 is more top end and power rather than low down torque.

I do run 1600 pistons in my 1500 and I did plane the block which does give me more torque than a standard 1500 but the cam and carbs are set up for mid-high range (3000-7000RPM). So more power overall but heaps more at the top end.

The general rule of thumb is more stroke will give you torque and shorter stroke will give you more top end power. The Avenger is very over square to begin with so it doesn't have that much stroke. so stroking it would help. I also used to use bigger Holden pistons in my race car which was bored out to around 1750cc.

Here is a dyno graph from my 1500

You can see the torque drops off a little just after the 3000 mark but then climbs up to it's peak just over 5000 RPM. A standard Avengers torque peak is around 3000-4200 RPM depending on the engine.

You can also set that the power curve is nice and smooth.

(http://i871.photobucket.com/albums/ab274/avenga76/1975%20avenger/IMG_1224_zps5933672d.jpg) (http://s871.photobucket.com/user/avenga76/media/1975%20avenger/IMG_1224_zps5933672d.jpg.html)
Title: Re: motor rebuild
Post by: old white 73 on December 04, 2014, 07:15:08 PM
update time, got my grubby mitts on an engine out of a english gt that'd been parked up for 10 years, got it running before we pulled it out.
this gives me an 's' head & better cam & it has the early twin carbs with adjustable jets- i'd just bought carbs & manifolds off trademe about 2 weeks earlier.
where am i at now? had a look inside found a bit of scoring on some bearings & cam & followers are pitted so they're off to get dealt to.
reamed out the gt exhaust manifold exits & fitted it in the car- yea i'm still using  a single carb for now, why bother? its w.o.f time & rather than patch  the exhaust i got a new 1 3/4 into 2 inch built now, + the twin carbs aren't ready to fit yet
what depth should the duplex timing cover be? i found scoring from the chain on the inside & the cover i've got is same as the single chain one on the other spare motor
Title: Re: motor rebuild
Post by: oldschool on December 05, 2014, 09:05:56 AM
My Alpine also has a duplex chain with a single chain cover...from the factory.
With the sump off I measured the clearance between the chain and inside the cover...it's only 5 thou!
So any end float in the crankshaft will cause the chain to foul the cover...particularly when the clutch is pressed.
Mine is okay, yours will need new crankshaft thrust washers.
Title: Re: motor rebuild
Post by: old white 73 on December 05, 2014, 05:58:35 PM
that explains a lot, bigger potential disaster avoided- heads at engine shop having a swim in the acid, pulled the valves out & all the exhaust ones have stretched badly, hmmm another sign its had a hard life.
before the  new exhaust was fitted i got it on the rollers to give me a baseline, 45 shetland ponies at the wheels @ 5000 revs, crazy thing is it had 40 of them @ 2000 revs- explains why trips to dunedin are sooooo slow, saddle hill at mosgiel is 2nd gear, lol.

Title: Re: motor rebuild
Post by: oldschool on December 05, 2014, 11:57:52 PM
The single carb 1300's, Hillman 1500's and Chrysler 1600's had a similar mild cam, you don't gain much by revving them...lol
All Hillman 1600's had a hot cam....which is why they'll beat a Chrysler 1600 any day of the week!
Interestingly the Hillman 1600 SC produces more torque down low than the TC version...from faster inlet flow, while the TC puts out more HP at higher RPM's...from better breathing.


Title: Re: motor rebuild
Post by: Paddy75 on December 15, 2014, 04:50:20 AM
From the Avenger 1970-77 Haynes manual.

1500 SC/TC
Inlet opens: 35/44 BTDC
Inlet Closes: 69/78 ABDC
Exhaust Opens: 69/69 BBDC
Exhaust Closes: 23/23 ATDC

The MK1/Hillman 1300 had the same camshaft as the SC 1250 apparently. There was a 1250 TC also so assuming the 1300 TC or 1.75CD carried over the 1250TC camshaft also: SC/TC
Inlet Opens: 38/44 BTDC
Inlet Closes: 66/78 ABDC
Exhaust Opens: 72/69 BBDC
Exhaust Closes: 20/23 ATDC

Listed for the 1600cc MK1 Haynes states no difference to the 1500cc. Unless they fitted the 1500TC camshaft to the early 1600 as standard, although that maybe wouldn't be ideal as the 1500 was crt 9.2:1 and the early 1600 8.6:1.
The MK2/Chrysler was noted for having better fuel economy and that's probably because of higher gearing rather than a milder camshaft and a slight increase of crt to 8.8:1.

I think the blue Haynes 'Avenger 1970-81' gives the full range of valve timing, if I find it I'll check.

Also to set the exhaust valve clearance and closing position for checking timing; 1500 SC 0.1'' (2.54mm) 22 BTDC, 1500 TC  0.1'' 12 BTDC.

1250 & 1300: SC 0.1'' 25 BTDC. TC 0.1'' 12 BTDC.

1500 SC 0.1'' 22 BTDC, 1500 TC  0.1'' 12 BTDC.

1600 up to Series 7 (Hillman): SC 0.1'' 19 BTDC. TC/175CD 0.1'' 12 BTDC. - Yeh much hotter at 19 degrees compared to 25 on others.

1600 Series 7 on (Chrysler): SC 0.1'' 25 BTDC. 175CD 0.1'' 12 BTDC




Title: Re: motor rebuild
Post by: oldschool on December 15, 2014, 06:54:03 PM
Had a look in my blue Haynes manual and the Hillman 1600 valve timing up to the series 7 is:

Inlet Opens 44 BTDC
Inlet Closes 86 ABDC
Exhaust Opens 66 BBDC
Exhaust closes 20 ATDC

7 series on (Chrysler) valve timing is:

Inlet Opens 38 BTDC
Inlet Closes 66 ABDC
Exhaust Opens 72 BBDC
Exhaust Closes 20 ATDC

The ratings of factory cams are determined by the IVO/EVC and IVC/EVO overlaps...

1250/1300/1500 SC is (35 + 23) and (69 + 69) = 196 (Mild)
Chrysler 1600 SC is (38 + 20) and (66 + 72) = 196 (Mild)
Hillman 1600 SC is (44 + 20) and (86 + 66) = 216 (Hot)
Hillman 1500/1600 TC is (44 + 23) and (78 + 69) = 214 (Hot)

So if you put ANY 1600 Hillman cam in your 1300, it'll turn into a little flyer Paddy!
Title: Re: motor rebuild
Post by: Paddy75 on December 16, 2014, 07:28:39 AM
Good idea! I see there is a 1.75CD on ebay with the MK1 linkage, just need a four stud manifold I suppose.

The 1300GT gave 69bhp with twins and 67bhp with the single CD175, I guess that had the hot camshaft. The camshaft sprocket is different on the 1250/1300cc so I guess you'd keep the 1600cc sprocket.

The Chrysler valve timing is very different from the Hillman by the looks of things, I guess this was to broaden the torque curve for higher overall gearing.

I know where one of my Grandfathers 1600 engines is lying in a ditch and have been meaning to pull it out and dismantle - well I assume its a 1600, could be a 1500 and as soon as you see the valve springs it tells you. Oh yeh, I forgot the manifolds! The 1600's all had twin downpipes and a more formed inlet. He had a 1500GL as well as a couple of 1600 Supers.

Anyhow I want to re-ring the pistons as there is a bit much blow out of the rocker, not too bad but a new set of rings is always a good precaution. Duh! I forgot also I have a set of 1300 pistons as well! Dunno if they are 8.6 or 8.8:1 the guy selling them stated 'Chrysler Avenger,' so maybe they are 8.8:1.

What I really ought to do is pick up a spare 1300 engine (they can be got for next to nothing) and build at me  leisure. I see a guy on ASOC runs a 1300 with 1300 pistons on a 1250 crank plus a supercharger, that must be some fun! 67bhp will do me just fine!

I don't think there was a hotter version of the 1300 on the MK2 or Sunbeam - what was the point I suppose!?

Pardon me for gazumping your thread Old White.
Title: Re: motor rebuild
Post by: oldschool on December 16, 2014, 08:55:14 AM
Yep all the TC 1250/1300/1600 Hillman's had the hot cam Paddy.

Here's a NOS Hillman 1600 SC hot cam on eBay for $40 quid.

http://www.ebay.co.uk/itm/Avenger-Sunbeam-Unused-Camshaft-71268711-believed-1300-or-1600-specification-/301071298009?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item46193f6dd9 (http://www.ebay.co.uk/itm/Avenger-Sunbeam-Unused-Camshaft-71268711-believed-1300-or-1600-specification-/301071298009?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item46193f6dd9)

I've confirmed the 71268711 part number is for a Hillman 1600 single carb.
71268712 is the part number for the twin carb Hillman.
Title: Re: motor rebuild
Post by: old white 73 on December 20, 2014, 10:56:39 PM
all this cam info is really handy guys, wish i'd checked the part no. of the 1 i sent away- should be ok though. got the head back & have ground out the exhaust ports abit to match the manifold i'm using, theres a 4mm diameter difference between them. something else i've found is the heads inlet ports are slightly smaller than the intake manifold ports, a 1mm dia difference with a dd1 (1500) manifold & a 2mm difference with a dd2,(1600?) thinking of putting a chamfer on the edge to help airflow while leaving the rest of the port alone-good or bad idea, opinions welcome & yes im using the dd1.
anyone else noticed the twin strombergs appear not to have ram tubes at the carb mouth like the singles do?- another addition i have in mind to try on the dyno later
Title: Re: motor rebuild
Post by: oldschool on December 21, 2014, 01:50:21 PM
My 1600 Alpine TC has a DD1 inlet manifold...am not sure what the difference between a DD1 and DD2 is!
A good idea to match up the inlet manifold and head ports to smooth the flow...we called it blueprinting in the old days!
The ram tube helps breathing at full throttle on the SC motor with its restrictive manifold...not needed on the TC as breathing is already far superior with the twin branch manifold.
Title: Re: motor rebuild
Post by: JoKer on December 22, 2014, 11:49:50 PM
hang on super chrger?
Title: Re: motor rebuild
Post by: old white 73 on January 07, 2015, 09:58:50 PM
think we've found some suitable valves in my scrap pile, mazda fe 2l are about the right length, 2mm taller above collet groove, just a few thou bigger in the stem which will let us ream out the guides to suit.
inlet valve head needs trimmed alot but exhaust isn't too far off for what we want
Title: Re: motor rebuild
Post by: JoKer on October 11, 2015, 01:52:43 PM
wow thats good info right there :P
Title: Re: motor rebuild
Post by: old white 73 on October 14, 2015, 08:13:28 PM
& we can use the s heads double springs with the mazdas valve caps, still waiting/looking for the right toyota motor to rob crank & maybe flywheel out've, by the way met a bloke who's stretched an avenger out to 2L with a cortina crank, apparently a fair bit of machining involved- went into a rally car.
theres also a dark red avenger running round otago he's stroked to 1700 offset grinding the the big ends, another x-race motor