Help me ballpark horsepower/torque on the 2.7 L build

[Tdskip]

Good morning and hope everybody’s had a good weekend so far. There’s obviously a lot going on right now so I hope people are taking care and staying safe.

As a detailed in another thread here I have a 2.7 L engine that Brothers in SoCal is helping me put together. I’m building this engine has a bit of a science project, not really chasing numbers or looking for bragging rights or anything like that. I’ve enjoyed the processing learned a lot, but it would be handy for planning purposes to get some idea of the horsepower/torque that this build is likely to result in.

There’s still some measuring and checking to do but if we assume;

2.7L displacement
2.0L heads ported and matched to larger displacement
8.5 to 9 CR
Street grind can, torque and mid-range grind
Dual Weber 44IDF

Where do you think that will put me?

I know there’s been some mention me to this but is there a cam profile that you would recommend for this.

Hope it is OK to start a new thread – this seems to be a fairly popular topic over the years so I wanted to pull it out rather than have it buried in the other discussion.

Thanks!

[wreck]

my guess would be 150 to 160 WHP . As long as you have a fairly good exhaust . You can put quite a large duration cam in a big type 4 and still have a very streetable engine as long as you match the compression to the cam . I've a 2600cc (103x78) with a 274 degree cam at 0.050 with 10.5 to 1 comp . With good throttle management it willl pull up a hill in 3rd gear at 2000 rpm . Thats in a Ghia that weighs 1000kg .
the 44's will be limiting it .

[Tdskip]

Thanks @wreck , appreciate the response.

I bet the Ghia really goes!

[wreck]

it's fun . So far only run on an 1/8 track , best time was 8.48 , on street tyres with a stock 215mm sachs clutch . I've upped the head flow and upped the cam slightly since then .

The great thing about large type 4's is the torque and the fact you can have a daily driven high performance air-cooled engine that can survive in a warm climate .

[Tdskip]

Glad you are enjoying it - I am looking forward to the torque too, being able to roll on power coming out of a turn is hugely enjoyable.

Thanks again, stay safe.

[falcor]

I think you should do a bit better than 160? thats what I get from my 2,3 litre with a Web 163/86b cam and 10:1 compression.
I dont know carbs at all but arent 44's 44 mm in diameter? If so thats 21% more surface area than my 40 mm ITB's.

[MegaRookie]

My first thoughts would be around 170 crank hp. This is also depending on the match of the components you mention + valve size, exhaust, how well the CR matches the cam and how well it is ported.

Ps. It is also depending on the dyno you go to Some are realistic and some are giving you more hp for your money.

[Tdskip]

Good morning, thanks for the response @falcor. You are running higher compression than I think I will be, but sounds like you have a very healthy engine.

@MegaRookie - thanks for the thoughts, and I will try to find a friendly dyno. Ha. I'm more just curious about the likely range than chasing any specific number, have one more project that I am trying to decide what to do with and how this one shapes up will help direct that.

I am likely leaving some power on the table by using the 44 IDF from what I can tell / have learned but I am more focused on drivability which I believe these will provide.

[falcor]

Yes but I think your 0.5 liters of engine size more will do alot more than my 2 points of compression does.
My guess is 175 hp +/- 15 hp depending on the supporting mods such as quality of headwork and exhaust etc.

[Tdskip]

Good morning. Brothers is porting my heads, think I need to focus on exhaust now since that will likely be a limiting factor. Thanks for the reminder on that.

[Steve Arndt]

If you still have 42x36 stock size valves you may hit around 150 hp.

[Tdskip]

Hi Steve - plan is to go bigger than stock, will be done as part of head prep. Great consideration however, thanks!

[wreck]

it would be interesting what professionals (Brothers) recommend and get flow wise out of your heads , if you can share that data .

after a little development I ended up with 47mm intake and 40mm exhaust valves . I think 40mm exhausts are as big as you can go , I had an issue with a porous bubble in the port wall just under the seat , lucky, I was able to fix the leak without welding in a simple manner ,maniseal and wedge of aluminium flat bar held in by the header flange . The hole showed how thin the port wall was with 40mm valves . I guess that is why 38mm is a popular size .
My exhaust flow is about 185cfm at 28" at 0.550" . Intakes flow 230cfm at the same lift . There is room to open the intakes up more but I'd loose air speed and also if you can't get it out don't put it in .

[Tdskip]

I will be happy to share what I find out after talking with Botheers and pass along what they recommend.

[Bills914-4]

Hello , I'll share my old 2800cc ( 10 years ago ) it made 180 hp & 185 torque
under 6000rpm @ the wheels on a chassis dyno, add 15% for flywheel h.p.
I was told & later learned it was under carbed and under cammed ( for me )

If I rebuilt this exact motor again I would not go more than 9.5 c.r. , if you go high on
c.r. go bigger on cam dur. on big motors ,(I currently run 320 adv. dur. )

84 x 103
48 x 38 self ported NON-welded heads
EMW J grind cam ( 106 lobe angle, [email protected] / 307 adv. x .500 lift with stock rockers
45 dells
10 to 1 c.r.
mallory unilite
1 7/8 C.F.R. tangerine exhaust

chasiss dyno.jpg