25 replies to this topic

[Chris Wilson]

Looking to go nostalgic and build a fast road turbo Volvo 240 or 740. I have a new factory late "red block" with piston oil squirters. Have a new head casting coming. I want to stroke it from the stock 2.3 litre 96mm bore X 80mm stroke to either 2.5 litres with 96mm bore and 86mm stroke (which is a factory offering in the Penta marine version of this engine), or, more wildly, to just under 2.8 litres with 96mm bore and 94.5mm stroke. There is a stroker kit commercially available for 2.5 and 2.8 litres, billet crank, billet rods and nice lightweight Omega forged pistons specifically for high boost turbo application with a -11.3 cc dish. I have not found anyone in the UK with personal experience of the 2.8 stroker kit though. Is it too much stroke V bore size.....? I feel adding stroke is better than going bigger on bore, for two reasons. the 2.3 blocks don't have a massive reserve of bore wall thickness, so staying 96mm is safe. And 96mm bore is already quite big for a turbo engine with flame travel probably compromised if it were much bigger.

 

 

the head will be the 2 valve per cylinder single OHC, not the 4 valve per cylinder 16 valve DOHC head. I intend upping the exhaust valve diameter from 35mm to 38mm, but leave the stock 44mm intake valves alone. It will have a staggered duration aftermarket cam and run on Motec sequential injection and coil on plug direct ignition.

 

Anyone any thoughts on going 2.8 litre? I can't see me wanting to rev it much beyond 7250 RPM, and I am looking for as much area under the torque curve more than peaky top end power. if i got a genuine 380 BHP at the flywheel with a rook of torque I'd be happy.

 

Thanks for reading.

Edited by Chris Wilson, 06 February 2016 - 17:41.

[MatsNorway]

You wont be needing a stroker engine to get 400hp, thats no problem with 2.3 even with 8V. One quick google and you will find several vids and threads about 500hp+ builds.

 

Where in the world are you located? In Scandinavia there are several engine builders that would easily be able to build your engine or help you do it.

[Chris Wilson]

Hi, thanks for the reply, building the engine isn't a problem, it's just deciding wheter the bore / stroke ratio is too extreme. I have a turbo 1.6 Toyota 4A-GE engine, based on a pukka Formula Atlantic engine that gives 400 BHP, but it needs revving to infinity and has bugger all real torque

 

http://www.gtr.co.uk...ding-turbo.html

 

I am after as much area under the torque curve as possible with this Volvo engine and if stroking out to 2.8 litres helps get it, great, but I don't want to get into extremes of piston skirt loadings or anything due to too short a rod.

 

I should have added to my first post that the rod centre to centre length of the rods in the stroker kit is 150mm.

Edited by Chris Wilson, 08 February 2016 - 14:20.

[ray b]

http://forums.turbob...s.com/index.php

 

try those guys as somebody there has built one to the max

 

btw I would think a 4v head is basic help

[MatsNorway]

Im surprised you did not get more replies. Lots of people here that knows a thing or two about engines.

[Lee Nicolle]

Build too application. Short stroke will rev far freely but have less torque. The Penta will be a grunter as all boat engines are.

The long stroke sounds a handgrenade in every way and maybe a nice dyno queen but useless and thirsty for road application

Why put bigger exhaust valves in? Seems odd, generally bigger intakes help. And they are fairly small in the great scheme of things. Though obviously depends on the port, both intake and exhaust.

I know little about those engines apart from they are quite tough,, and heavy!

Chevy 2 midget engines were using over 1 3/4" intakes and 1.5 exhaust with [from memory] a similiar bore and stroke. A bloke I spoke too once used a volvo [70s]  and called a Chevy 2. Why? Who really knows. It went ok for the day.

 

I would dispute a turbo 4 AGE making 400, in my experience 300 is closer too the mark and they make near that n/a anyway.

As I often say 300 real and 400 in the pub! Dyno queens may but with huge boost that makes the engine a handgrenade.

[gruntguru]

Optimum valve ratio moves toward exhaust in blown engines and continues that direction with increasing boost.

 

400 from a turbo 4AGE? Easy.

 

Any NA that makes 300 can EASILY be boosted to 600. Only takes about 1 bar.

[Canuck]

1 bar of gold pressed Latinum!

There was an interesting article in Hot Rod mag a couple of years ago (I think McG mentioned it), where they boosted a 4.8L LS engine with increasing boost until they ran out of dyno time. IIRC, the final numbers were well over 1000 HP on a mostly stock engine. And of course, NRE's engine builds can be seen all over YouTube as they prowl the streets with 1300+.

[Chris Wilson]

Optimum valve ratio moves toward exhaust in blown engines and continues that direction with increasing boost.

 

400 from a turbo 4AGE? Easy.

 

Any NA that makes 300 can EASILY be boosted to 600. Only takes about 1 bar.

 

 

Bear in mind this is NOT a street engine, it's based on a very radical Formula Atlantic crank, custom rods, and pistons, custom cams, dry sumped, in a late supercharger ribbed block with custom steel main caps. It would give more, but I chickened out at 1.3 bar. As an N/A Formula Atlantic on 48DCOE side draughts it made about 275 BHP (at over 10,000 RPM....).

Edited by Chris Wilson, 10 February 2016 - 14:43.

[Fat Boy]

 

I would dispute a turbo 4 AGE making 400, in my experience 300 is closer too the mark and they make near that n/a anyway.

As I often say 300 real and 400 in the pub! Dyno queens may but with huge boost that makes the engine a handgrenade.

 

250 was not particularly difficult on those engines N/A with limited compression, cams, valves and RPM. 400 out of a turbo engine is really not much of a stretch at all.

 

Keeping the guts of the thing on the inside might be a trick, but that's more an issue of RPM than actual power in the range we're talking.

[Lee Nicolle]

 

Optimum valve ratio moves toward exhaust in blown engines and continues that direction with increasing boost.

 

400 from a turbo 4AGE? Easy.

 

Any NA that makes 300 can EASILY be boosted to 600. Only takes about 1 bar.

 

 

Bear in mind this is NOT a street engine, it's based on a very radical Formula Atlantic crank, custom rods, and pistons, custom cams, dry sumped, in a late supercharger ribbed block with custom steel main caps. It would give more, but I chickened out at 1.3 bar. As an N/A Formula Atlantic on 48DCOE side draughts it made about 275 BHP (at over 10,000 RPM....).

 

A Pacific engine would never suit turbo. High comp and a lot of RPM

. For turbo you would have to use different pistons and probably head too. Different cams and less RPM so it does not spew internals all over the shop

1.3 around 20lb? hardly a reliable boost anyway. Ideal for dyno queens. May be ok for drags where doing a meeting without a meltdown is amazing! I love these figures,, 600hp RB30 Nissans that have useless power and explode every second start. 1000hp Chevs that on a racetrack go slower than a 500hp n/a engine,,,, and usually make big oil downs too.

I have raced against 400hp [500 in the pub] real turbo 2.2-2.5 l engines in Sports Sedans and they can be fast but balk them off the corners and you do not see them again! As they get off boost and become about a 100hp! They can turn decent lap times by themselves but seldom in traffic. Usually with about 10 lb so they do not explode every lap!

A friend used those engines in a 1.6 offroad buggy, 8000 rpm all the time but in the end the main advantage was the light weight of the engine in comparison the the torquier L series Nissan.

And all the internal stuff cost more than I would spend on a Chev too for double the power.

[Chris Wilson]

The Atlantic engine, when turbo charged, got different cams, different valve springs, lower compression turbo pistons, different heftier rods, a big intercooler, and was put on a single throttle body injection.

 

It's all in the build I linked to earlier. Very different to when it was an N/A. Even got a late supercharger block (much stiffer) with custom steel main caps.

[gruntguru]

 

A Pacific engine would never suit turbo. High comp and a lot of RPM

. For turbo you would have to use different pistons and probably head too. Different cams and less RPM so it does not spew internals all over the shop

1.3 around 20lb? hardly a reliable boost anyway. Ideal for dyno queens. May be ok for drags where doing a meeting without a meltdown is amazing! I love these figures,, 600hp RB30 Nissans that have useless power and explode every second start. 1000hp Chevs that on a racetrack go slower than a 500hp n/a engine,,,, and usually make big oil downs too.

I have raced against 400hp [500 in the pub] real turbo 2.2-2.5 l engines in Sports Sedans and they can be fast but balk them off the corners and you do not see them again! As they get off boost and become about a 100hp! They can turn decent lap times by themselves but seldom in traffic. Usually with about 10 lb so they do not explode every lap!

A friend used those engines in a 1.6 offroad buggy, 8000 rpm all the time but in the end the main advantage was the light weight of the engine in comparison the the torquier L series Nissan.

And all the internal stuff cost more than I would spend on a Chev too for double the power.

I sometimes wonder what you are doing hanging around a Formula One technical forum.

[desmo]

If F1 did the smart thing and mandated pushrod Chevy V8s instead of hybrids...

[Lee Nicolle]

Dont laugh, recreating the now very favored past,, F5000 which on some tracks were faster tan 3 litre F1.

Sound far better too than 1.5 V6 turbos with megaphone exhausts and cost about 2% of the current engine costs.

Ferrari may well complain!

[Lee Nicolle]

The Atlantic engine, when turbo charged, got different cams, different valve springs, lower compression turbo pistons, different heftier rods, a big intercooler, and was put on a single throttle body injection.

 

It's all in the build I linked to earlier. Very different to when it was an N/A. Even got a late supercharger block (much stiffer) with custom steel main caps.

So what was left of the Atlantic engine? Just a 4AGZE supercharged race engine with a turbo.

As for all the supposed hporsepower numbers I have driven past all the hi tech lo speed hairdryer engines with supposedly far more power  with a simple tough and reliable carby Chev. That did 2500 racing ks and was then updated a bit. Engines built simply and [comparitivly] cheaply.

Modern very hi tech turbo engines in such as the Sports Cars raced last weekend at Bathurst are fairly reliable cars BUT cost a whole lot of money!

Oh and how much boost were they using? About half of what is claimed for 400hp 1.6 Toyotas!

[Catalina Park]

Dont laugh, recreating the now very favored past,, F5000 which on some tracks were faster tan 3 litre F1.

 

Sorry Lee, you mean that some old F1 cars on control tyres were slower than F5000 on free tyres.
When F1 cars were allowed to freely run with F5000 they just ran away from them.

[Lee Nicolle]

Sorry Lee, you mean that some old F1 cars on control tyres were slower than F5000 on free tyres.
When F1 cars were allowed to freely run with F5000 they just ran away from them.

???? They ran F1 cars with 5000s in what? the 79 Oz series and where were the F1s? Making up the numbers.

In both the UK and US 5000s lapped faster than F1 on some tracks. Not even at the same meeting.

The 'Purists' seem to forget that F1 3L engine,s were decidedly short on straight line grunt. Tracks that suited that is where the 5000s would shine.

[imaginesix]

Im surprised you did not get more replies. Lots of people here that knows a thing or two about engines.

 
 

I would dispute a turbo 4 AGE making 400, in my experience 300 is closer too the mark and they make near that n/a anyway.
As I often say 300 real and 400 in the pub! Dyno queens may but with huge boost that makes the engine a handgrenade.

Lesson learned. In order to get a strong response rate in the tech forum, just say something plainly wrong.

1/2 of all tech posts are probably driven by a supercharged Lee.

[MatsNorway]

Hehe. He gets them going from time to time.

[gruntguru]

I will have to bite now.

 

I recall watching a Rothmans series race for F5000 at Surfers Paradise International raceway in '78 or '79 and seeing two obsolete Cosworth powered F1 cars finish 1 2 ahead of a field of F5000s.

[Lee Nicolle]

I will have to bite now.

 

I recall watching a Rothmans series race for F5000 at Surfers Paradise International raceway in '78 or '79 and seeing two obsolete Cosworth powered F1 cars finish 1 2 ahead of a field of F5000s.

I suspect most will remember differently. I cannot remember them winning at all. Just made up the  front running numbers,, as for obsolete they were no more than a year old. Most of the local 5000s were quite a bit older!

I watched that series on TV. The AIR round at least is on You Tube

[Lee Nicolle]

Back on subject on my scrounge for some tyres last weekend I had a look at a very good midget. Excellent set up, Two engines, 3 diffs, 3 front axles plus the usual spares of consumables such as shocks and radius rods. He islooking for a top driver as the last one had a big accident [shown on bookface]  and his wife has put her foot down. In this case probably with reason as he broke his back last big one.

Fontana  alloy engine very loosely based on a Sesco Chev [327 cut in half]. 4 130 bore and 3.1 stroke and 386hp @ 9000 rpm. 2 valve fuel injected race engine.Very high compression on methanol.

These are very strong engines and also very tough as they run 2-3 times a week in the Super Series.

No 400hp turbo Toyotas and they are legal!!

 

It probably answers the very long stroke question too, the 86mm Penta stroke probably best suited to the application.

Edited by Lee Nicolle, 23 February 2016 - 08:36.

[gruntguru]

 

I suspect most will remember differently. I cannot remember them winning at all.

I was there. Surfers Paradise International Raceway 1979. https://en.wikipedia...#Series_results

Kennedy won the race in a Wolf WR4. He and Lees (Ensign) led for most of the race until Lees retired.

 

The Wolf was an early 1978 model. The Ensign 1977. Neither design was particularly successful when they competed in F1 - even with the likes of Jodi Sheckter (Wolf) and Clay Reggazoni (Ensign) at the wheel.

[Catalina Park]

I was there. Surfers Paradise International Raceway 1979. https://en.wikipedia...#Series_results
Kennedy won the race in a Wolf WR4. He and Lees (Ensign) led for most of the race until Lees retired.
 
The Wolf was an early 1978 model. The Ensign 1977. Neither design was particularly successful when they competed in F1 - even with the likes of Jodi Sheckter (Wolf) and Clay Reggazoni (Ensign) at the wheel.

The team bought two Wolfs, WR3 and WR4, and an Ensign (MN09) they were all 1977 models. (though WR4 didn't make it's debut till early 1978 it was still the same design as the four WR1 to WR4 cars)
David Kennedy drove Wolf chassis WR4 in the four races, he got a third at Sandown, retired at Adelaide after an accident, 1st at Surfers and retired at Oran Park.
Geoff Lees drove the Ensign in the first two races, it got a Second at Sandown, Retired at Adelaide. He switched to the Wolf WR3 at Surfers where it retired (accident) and DNS at Oran Park.
John Goss almost raced the Ensign at Oran Park.

The Wolf WR1 to WR4 was a fairly successful design in 1977. Jody Scheckter won three races with car WR1. That particular chassis never finished a race lower and 3rd place in its 11 finishes. (it won it's debut GP in Argentina, won Monaco even finished third at Monaco in 1978)

Edited by Catalina Park, 24 February 2016 - 08:18.

[gruntguru]

Thanks CP - good info.