1500 v 1600?

[streetracer75]

Hi I am new to this site and am in the process of trying to find one of these cars to buy. I have looked at a few and would like to ask if the 1500 or 1600 engine is better with regard to tuning potential?

I have looked at a 1973 Hillman Avenger 1500 GLS and a later 1975 1600 GLS. (I was originally wanting a GT but they are now almost impossible to find in the UK)

The idea is to tune it for fast street use (maybe Tiger performance) rather than race or track.

I would initially like to do this by "bolt-on" upgrades like air intake, 4-into-1, big bore exhaust, hot cam etc, before getting into any serious head or block work which will probably follow later.
Thanks.


Gary

[blekkja]

Rich will come along shortly: he has gone for a 1500 over the 1600 in his custom build because it is more streetable amongst other reasons. You are sacrificing top speed for low end. Depends how you plan to drive it. Also what ratio your diff is so you can get the sweet spots in the right range of speed.


I've a 1500 in mine and it does the job... never thought about replacing it. Well recently at least: it was only going to be in there as a short term measure while I rebuilt my hot motor. But I was having too much fun as is and it refuses to die.


Another option to think about is tracking down a south american 1800. These have a heavier block. It goes without saying as well, especially being in the UK, that you could pull the guts out of a Sunbeam and transplant them. But the stock motor is cool enough as it is.

[streetracer75]

Hi thanks for that. I am leaning towards the 1500 car. Somebody told me they have a higher compression and shorter stroke than the 1600 engine?

I guess I am looking for a little more bottom end grunt, rather than top speed.

[JoKer]

my tuned 1600 is almost unusable on the street

avenga's 1500 is/was daily street driven as far as I know

both are pretty much the same tune/mods, electric ignition, cam, twin dellorrto's, extactors, balanced flywheels/crank, polished/port matched intake/exhaust

[blekkja]

Yeah I think you want the 1500 then mate. I'm not sure if the UK is anything like us but here in NZ when you hit the magical 40 year mark everything gets cheaper and better too!


What are you thinking about in the carburettor side of things? Because I'd recommend considering running a big single. I've recently "upgraded" to twin 1.5 strombergs and I'm not sure if that was the best idea. While they give me a better feel on the open road I has a huge fan of the 1.75 stromburg I used to run. Way simpler and better at lower revs. Those only came out on one model year, 1976 from memory, but it could be worth investigating a weber or something.

[oldschool]

Unless you find a 1500 with twin carbs (GT/GLS) the 1600 engine is much better because even the single carb model has free flow manifolds and a hotter cam than the single carb 1500. Tip: Don't get a Chrysler 1600 either as it has the same wussy cam as the single carb Hillman 1500!
There's no need to change the cam if you get a 1500 or 1600 GLS/GT as they're good up to 7000 rpm while providing lots of low down torque.
The GT/GLS already has a lightened flywheel, so just the carbs/exhaust to modify to make a little flyer!!

[streetracer75]

Hey that's interesting. I didn't know the GT/GLS had a lighted flywheel?

Its definitely a GLS I am going to buy. Just a question of 1500 or later model 1600? I had started off looking for a GT but there just arn't any left here. As far as I know the GLS is the same in every respect other than trim level, so I figured it was the next best thing.

The car I have my eye on is a 1500 GLS with twin stromberg set up.

Does the GLS also have the upgraded "S" head that I keep reading about on here as well?

Thanks.

[oldschool]

All the 1500 GT/GLS twin carb motors had the 'S' head with slightly bigger inlet valves. They went back to the standard head on all 1600 motors, but the 1600 GT/GLS is still more powerful than the 1500 'S' GT/GLS because of that extra 100cc...lol

[streetracer75]

Ok now I am starting to build a picture of what I want and what would be best to start with to achieve this.

Other than the twin carbs, head and flywheel... what else did the GT/GLS have over and above the standard DL and Super models?

[JoKer]

amazing info in this thread!

[oldschool]

Ok now I am starting to build a picture of what I want and what would be best to start with to achieve this.
Other than the twin carbs, head and flywheel... what else did the GT/GLS have over and above the standard DL and Super models?

The GT/GLS motors had double valve springs, so easy to check if the cars had a transplant?!
Just shine a torch in the oil filler hole and see if there's double valve springs in there...lol
They also used the Lucas 43D non-vacuum dizzy, had extra bracing between the sump and gearbox and between the x member and chassis (see Scarlet thread for photos) along with larger rear wheel cylinders.
The dash was completely different of course and included two speed wipers, two speed heater fan and dimming dash lights, but no clock!
I put a Chrysler clock in my GLS (Alpine) where the heater switch was and moved that back to the original Super position under the dash, can see a photo in my thread.

[oldschool]

What are you thinking about in the carburettor side of things? Because I'd recommend considering running a big single. I've recently "upgraded" to twin 1.5 strombergs and I'm not sure if that was the best idea. While they give me a better feel on the open road I has a huge fan of the 1.75 stromberg I used to run. Way simpler and better at lower revs. Those only came out on one model year, 1976 from memory, but it could be worth investigating a weber or something.

Yeah those 1.75" CD's/SU's are a good idea. Pretty well impossible to find factory ones, just get a Rover 3500 1.75" one and modify the 1.5" inlet manifold to suit, similar to what Azza1600 did.
The twin 1.5" carbies do have a bad rep...less torque than a single and hard to tune.
The tuning problem is caused by worn throttle spindles upsetting the mixture and causing rough running, particularly at idle...my Alpine idles like it's got a lumpy cam...haha
A poor design really, the throttle cable connects to a lever on the side of the spindles...in effect pulling them 'towards' the cable mount...a recipe for rapid wear.
What's needed is a neutral 'rotary' motion to minimise wear and that's what the DL/Super had with their mechanical throttle linkage.
Many of those cheapie Avengers still have no wear in their throttle spindles!
While the mechanical linkage was good for the carby, it was trying for the driver, often causing 'bunny hop' starts in manual Avengers as it was over sensitive and affected by engine movement.
When the Chrysler model came out all Avenger throttles were cable operated...it helped with smooth starts...but no good for the carby!
They did make an attempt to lessen the problem by installing a half-round cable guide on the throttle spindle to get a more rotary motion.
To fix the problem completely two 'diametrically opposed' throttle cables are required, which is what expensive cars like Ferrari used!

[avenga]

I like the 1500's better. as the others said, it has a higher compression ratio and shorter stroke.

Mine has an 'S' head so it has the bigger values and the double valve springs. I have also ported and blue printed the head, along whith extractors, dual dellortos etc.

I am making above Tiger power and it is very streetable.

I used to race a bored out 1600 and I agree with Joker, 1500 for the street and 1600 for the track.

1975 Hillman Avenger 1500 Dyno Run

[streetracer75]

The GT/GLS motors had double valve springs, so easy to check if the cars had a transplant?!
Just shine a torch in the oil filler hole and see if there's double valve springs in there...lol
They also used the Lucas 43D non-vacuum dizzy, had extra bracing between the sump and gearbox and between the x member and chassis (see Scarlet thread for photos) along with larger rear wheel cylinders.
The dash was completely different of course and included two speed wipers, two speed heater fan and dimming dash lights, but no clock!
I put a Chrysler clock in my GLS (Alpine) where the heater switch was and moved that back to the original Super position under the dash, can see a photo in my thread.

Did the GT/GLS also have a dupelex timing chain?

[streetracer75]

I like the 1500's better. as the others said, it has a higher compression ratio and shorter stroke.

Mine has an 'S' head so it has the bigger values and the double valve springs. I have also ported and blue printed the head, along whith extractors, dual dellortos etc.

I am making above Tiger power and it is very streetable.

I used to race a bored out 1600 and I agree with Joker, 1500 for the street and 1600 for the track.

1975 Hillman Avenger 1500 Dyno Run

That's interesting that most of you seem to think the 1500 is a better option. Your car looks a real beast!