Big 6 Healey engine builder

[HealeyPassion]

Guys got a question for the racers.... who are the experts on Healey heads?... names/numbers? I'm considering an "improved" head for my 3L 6cyl... would prefer an improved cast head (I don't think the cost of an aluminum head would be cost effective for my non-racer Healey). Also, would think an effective header system would match up with the improved head. I have to believe the header technology has advanced since the factory race/rally headers.. so would be interested in who has really studied this area of the engine... improved extraction..primary/secondary lengths etc.

Okay, so what I'm hoping for is 20% with improved head and headers... is this unrealistic.

Thanks!!!
Steve
https://stevesaustinhealey.com

 

[HealeyRick]

Okay, so what I'm hoping for is 20% with improved head and headers... is this unrealistic.

Thanks!!!
Steve
https://stevesaustinhealey.com

Time to build a Nasty Boy!

 

[dougie]

Steve -

As you know the head/valves/valve train all need to work in harmony with the rest of your motor, i.e. cam, pistons, induction system. I found out the hard way with my first race motor build....you can't just start adding performance "gofast"
goodies without having a clear plan ands specific goals.

I did all the porting and polishing on my current iron race head, but I had it flow tested before and after so I had a good idea of where I needed to be to support the race tuned triple 2" SU HD8's and specific cam I run. Then it was to the chassis dyno for further testing and tweaks. So you want a 20% improvement....
In horse power, torque, top speed and where are you now?

I'm sure Richard (BoyRacer) will chime in, we use the same machine shop and dyno facility. He also has designed and produced (small batches) 6-cylinder headers which are the finest I've seen. I run a pair on my '57.

I could PM you the specific shops I mentioned, but it's a slippery slope you're on.

 

[HealeyPassion]

Dougie, I was hoping to hear from you... your machine looks super impressive (watched the videos). Believe me I do understand that it's a slippery slop. I've slide down it with my C5 Vette... 428 hp at rear wheels..etc. etc. from the stock block 5.7L... other than the lower end everything else is different.

But I digress... with my Healey I have the 6 injector efi dialed in ... it matches the BJ8 cam which Dema Elgin cut to improve the lobe separation just a bit to favor injection... so really don't want to touch that... engine balance is racer level. But.. head is stock as a rock... and stock cast headers (but match ported). The intake manifolds are factory tri-carb chamfered to match the ports. But all in all no improvements in head and headers. So my desire would be to JUST improve the head and headers.

We ran a stock, nice running, recently tuned BJ7 on a chassis dyno... then ran mine.. same dyno. The stock BJ7 put down 98 hp at the rear wheels... mine put down 131 hp. So that's where I'm starting.

Why my desire for 20%??... I went to the Texas Healey Roundup in Bastrop, TX in April... I live at 6,700'.. so it was like getting a free 20% hp boost running at basically sea level. That equates to about 20%... the car felt lighter and more responsive, of course... so I'd like it to feel like that where I live.

Thanks!!
Steve

 

[HealeyPassion]

Oh, and Dougie, those headers are absolutely beautiful. I'm wondering though if they are more for racing...i.e. high rpm. I'm thinking of something that maintains velocity for mid-rpm response.

Steve

 

[DerekJ]

Dougie,

Just out of interest, what made you chose the triple SU's over Webers?

I have a fast road set up with 2 HD8s at present. I may also go to an aluminium head and Race profile DWR cam and would fit 3 carbs. But which carbs? SUs or Webers. I wont be racing just doing hillclimbs and sprints so Im leaning towards the SUs. What are your thoughts and experiences on this. Ive got forged pistons but I dont really see myself going full whack for a steel crank and rods etc.

 

[andrea]

Hi Steve
Is really important that your engine must be race balanced, my engine run without needing the front damper-
I have the original flywheel to have one good reply at lower and middle rpm and improved camshaft for street top use(nearest to BJ8 phase)
I have 3 Weber 45 DCOE in the final configuration-
but your injection system will be sure better than my solution
My suggestion is don't exclude aluminum heads- it is easy
to work and have increased heath exchange rate-
ask more information to Lin Rose, that I remember have the aluminium head on his 3000
https://picasaweb.google.com/lh/photo/pZTwRRW5JX0svgWBBWn_ptMTjNZETYmyPJy0liipFm0?feat=directlink
https://picasaweb.google.com/lh/photo/4nnIjQRLvoPdjiwwTJfes9MTjNZETYmyPJy0liipFm0?feat=directlink
This is my 2,6 engine at the first start -equipped with the
3 Webers- some flames -but increasing the diameter of jets
and changing the electric fuel pump, solved the problem
I have poor fuel supply for the acceleration pump of the 3 WBS
Now the engine run quite- with a glass of water on it- also at
5000 rpm
Cheers
Andrea

 

[EV2239]

The camshaft is the only thing that makes 20%, the nest head in the business might give 10% if you were lucky.

You need more revs to get more power and cams do that.

Ash

 

[Superwrench]

Check out Denis Welch. They have a cnc ported cast iron head for exchange for yours, or they will do yours. Not too bad a price. They have some nice cams also. If you want more than 20% check out isystemsperformance.com. These guys helped NASCAR get 850 hp out of the small block chevy. Like Dougie says, everything has to work together. good luck

 

[John Turney]

on the exchange cast iron head. I have DW's aluminum one and several other of his bits. Talk to them and they can help you put together a package that should meet your needs. That's what they did for me.

 

[Bob_Spidell]

Can't tell for sure from the photo, but it looks like all 6 primaries go to a single collector; does that mean this becomes (essentially) single exhaust? Or is it just the photo?

 

[dougie]

Can't tell for sure from the photo, but it looks like all 6 primaries go to a single collector; does that mean this becomes (essentially) single exhaust? Or is it just the photo?

Just the angle of the photo....there's 2 separate collectors.

Steve, I'm reviewing some of my build sheets and dyno runs to see what top end improvements helped the most.

Derek, my goal from the start for my '57 100-6 was to prepare and present a "period" vintage race car as one would have seen in the US in the late 50's and early 60's. It's prepared to FIA GT 2 regulations for production sports cars though, this does allow for Weber's. They didn't allow them in SCCA at the time however, and they governed most of the sports car races in the US. My car can still driven on the street and with the Ruddspeed manifold it has the period look that appeals to me. For true "all-out" performance Weber's would be the best choice, that's just not my intention.

 

[BoyRacer]

Power is made in the head, not so much with the cam. Keep your cam relatively mild. You do not want to over-cam the engine. For example, the Iskenderian T-3-6 grind, or something comparable, is perfect for a hot street car. You can find the specs on-line. Do NOT go any bigger with the cam unless you want your power band to be in the 6-7000 RPM range.

Advance the cam. This will give you more low-end torque. Especially since you have now up-rated your cam with more overlap that saps some of your low-end torque. I have offset keys so if you are interested - contact me with a PM.

As for the head, take it to any good, reputable, race engine prep shop and have them do a pocket port and open up the runners. If they do not have a flow bench, then do not use them.

You should replace those odd size British valves with larger American stainless steel swirl valves (less expensive and better quality than stock valves) that have longer stems so you can use good quality American springs (also less expensive) that will allow you to use more valve lift.

The stock rocker arm ratio is 1.43:1. Don't believe the cam grinders that claim it is 1.5:1. A higher ratio rocker will give you the breathing you need to get that 20%. You may need to notch your block for exhaust valve clearance. Contact me with a PM for more info on high ratio rockers.

My iron head race engine, with 11.3:1 compression, higher ratio rockers, a cam similar to the Isky T-3-6, advanced 4 degrees, makes 231 HP at 5800 RPM at the flywheel. Torque is over 200 ft lbs from 3000 RPM to over 6000 RPM. Sorry, we never measure anything under 3000 RPM ...it's a race motor.

If you do some or all of the above, you may need some good headers .... like the ones I make .... that are shown on Dougie's post.

 

[HealeyPassion]

Hey BoyRacer thanks for chimming in. I've PMed you with some more detail. So, you made those beautiful headers for Dougie!... look beautiful... and, I suspect, work great. These look like they incorporate some modern header techniques. I have to believe that old style works headers, while great in the day, are not the most effecient given what we now know about scavaging exhaust today.

I found what you said about the head extremely interesting! I'll have to check out the specs on the cam. The issue with performance cams and my efi is that injection systems like vacuum, which if I understand it correctly, is generated by lobe separation angle (LSA)... so when Dema Elgin cut my BJ8 cam he pushed the LSA as far as it would allow... engine runs great. So if the hot cam has little LSA, which is common with carb. engines, it won't work well on my engine. In fact, it is my understanding that one of the reasons slapping on efi to a hot cam engine never works out well is the LSA is to narrow to service the injection... results, poor throttle response, etc.

Cheers,
Steve
https://stevesaustinhealey.com

 

[DerekJ]

Thanks for the explanation Dougie, I also want to be able to drive my car regularly on the road so don't want to go too extreme. I like the the triple 2 inch SU set up. I think a lot of people probably switch to Webers when they don't really need to because, lets face it, they look pretty sexy under the hood.

Great comments re the head from Richard. I'll compare the Isky T-3-6 grind to my DWR8. I dont live that far from DWR so I'll have to go up there and have a chat to them. Jeremy Welch built the engine for my car which was owned by a friend of his at the time.

How powerful can you get? Three weeks ago I drove to a sunday afternoon park and show and pulled up next to a scruffy looking 3000. It was Healey blue, last painted about 15 years ago with a scratched, dull, navy blue hard top and filthy wire wheels. I noticed the Classic Marathon and Alpine stickers on the hard top and got chatting to the owner. Over the last 10 years he had put on just about everything you can throw at a Healey and this wolf in sheeps clothing came in at 298 bhp on his last dyno test!

 

[BoyRacer]

298 bhp? Hmmmm.
As a long time racer, I have heard many sayings. One of them is: "When the green flag drops, the bull***t stops."

 

[DerekJ]

That's a fair comment Richard however it does seem that getting close to 300 at the flywheel is where quite a few guys are at over here.

 

[bob hughes]

That's a fair comment Richard however it does seem that getting close to 300 at the flywheel is where quite a few guys are at over here.

Yup

I can second that, not from personal experience of course but an associate of mine builds them for a living and and races them, and that is what he is getting.

I suppose that you would expect that after spending over £14,000 just on the engine.



Bob

 

[DerekJ]

Bob
That wouldn't be Bill Rawles down there in Hampshire would it?

 

[BoyRacer]

I'm still skeptical. I've been racing a long time. Talk is cheap. Dyno sheets are better evidence. First question I have is: At what RPM are these engines making 300 HP? Secondly, what kind of torque are these engines making, and at what RPM?
We have another old saying here in the US: horsepower sells cars - torque wins races.