Calling Aiton Buchan if you're out there, regarding low down torque.

[jakesmig]

Aiton,
Read your article in the December mag and notice you run a Holley carb with a large dia. filter & you miss low down torque / power. I used to run with a 3.5RV8 with an Eddelbrock 4 barrel carb with the same type of filter and also seemed to suffer in the lower range rpm. The staff at RPI Engineering in Norfolk advised that the RV8 didn't like the volume of air that the filter allowed and suggested closing off some of the element.
This I tried using the old faithfull gaffer tape, working up to closing off about 75% of the filter. I certainly noticed a real improvement low down and no loss high up.
Don't know if this would be the same for the Stag V8 but it may be worth a shot.
Bye the Bye, what size is your Holley carb, my RV8 had a 600cfm. Holley when I bought it which was too big for the 3500RV8 so I changed to the 500cfm Eddelbrock which ran much smoother. Downside, the bores in my V8 were shot & it pumped out more oil through the old rope seal behind the flywheel better than the Torrey Canyon dumped in the Channel. New seals never lasted verry long so I changed to a 3.9RV8 with fuel injection before I got to the ultimate gaffer tape solution.

Regards,
John

[V Mad]

Aiton,
The staff at RPI Engineering in Norfolk advised that the RV8 didn't like the volume of air that the filter allowed and suggested closing off some of the element.
Regards,
John

Building torque in an engine is all about getting the max amount of air (mixture) into the cylinders. Blocking the inlet is certainly a novel way to do that. Maybe the mixture was too weak and a larger jet would have been good?

What you say about 'big' carburettors thoough has some bearing on lack of torque at low revs; with a very large venturii the gas flow is just too low. A 390 4bbl is not a bad size for the 3.5 engine.

I read Mr Buchan's article and he asked quite a few questions, unfortunately he did not give a contact so we could send out comments.

[Staggering About]

Aiton is a local member but he's not very active. The pics in the mag are 2 years old. I've sent him an email telling him about this post. I've also asked his permission to send you his address. I'll be in touch if he does.
Alan
Grampian Convener.

[AitonB]

Queries in magazine - Low Torque

I have a 390 Holley fitted. I wouldn't say the torque is particularly low just not so good as before at low revs. ( I did get jets for the Stag engine fitted). I have heard this before and there is a trade off against performance gains elsewhere. I think the issues I have are around tuning. I have been recommended various "experts" who have ended up leaving car worse than before. It is difficult to find mechanics who have even seen a carb never mind set it up. Have had better success with colour tune at home.


regards
Aiton

[Speedytriple3503]

I have a 390 Holley fitted. I wouldn't say the torque is particularly low just not so good as before at low revs. ( I did get jets for the Stag engine fitted). I have heard this before and there is a trade off against performance gains elsewhere. I think the issues I have are around tuning. I have been recommended various "experts" who have ended up leaving car worse than before. It is difficult to find mechanics who have even seen a carb never mind set it up. Have had better success with colour tune at home.


regards
Aiton

I have to agree with Aiton here. Although my Stag runs standard strombergs I have a TR which runs a mildly modified 4.6L RV8 and this has had a Holley 390 on it now for some years. The carb is perfectly big enough to cope with the extra capacity so a 390 on a Stag would, I think be about right size wise. As Aiton says, the real issue is finding someone who is skilled enough to tune and set the thing up properly. I went through a couple of "experts" before finding a place that knew what they were doing and deal with Holleys on a regular basis - not cheap but the results were good. Prior to that the car had been left running too rich so it failed the MoT or had a tendency to hesitate on acceleration.

[Guest]

I went through a couple of "experts" before finding a place that knew what they were doing and deal with Holleys on a regular basis - not cheap but the results were good. Prior to that the car had been left running too rich so it failed the MoT or had a tendency to hesitate on acceleration.

Mines got a RV8 with Mallory twin-point dizzy and an Edelbrock carb (I thought it was a Holley), and I too struggled to find someone who knew how to set it all up right. I found a company about 25 miles from me in Hants and was just wondering who you used?

[Speedytriple3503]

Mines got a RV8 with Mallory twin-point dizzy and an Edelbrock carb (I thought it was a Holley), and I too struggled to find someone who knew how to set it all up right. I found a company about 25 miles from me in Hants and was just wondering who you used?

Hi. I used a company called GRL motors in Woking. Run by a guy called Ian Smith. As I say, he wasn't cheap but did transform the car and (touch wood) I haven't had to touch the carb since, which is kind of the point with a fixed jet carb to my mind.

Some years ago I went to the Airey Tuning Co nr Alresford. The guy there was very good with SUs and the like (had those on the car then). Not sure If he is even around these days or knows Holleys or similar but he did know his way around other carbs.

Mike

[Guest]

Hello Mike,

Thanks for that. Tom Airey knows his stuff and is, as far as I know, still in business. I called him about my issue and the only way he wanted to do it was for a fixed fee of £250.00 to get it all set-up and then tested on his dyno - which was too strong for me.

I used Pauls Place near Wickham, Hants. They set up the dizzy (my local garage couldn't get it to run properly with the vacuum advance connected and wern't that interested in researching how too) and carb jetting (again the local garage didn't have much of an idea) and charged about £100 I think it was. Really transformed the car and I would recommend them to anyone.

Ian

[Speedytriple3503]

That's interesting. I have a friend who lives in Swanmore with a Stag which needs the carbs doing.Will pass on the details to him as it's local for him. Mike

[Guest]

It's right on his doorstep - Shedfield is the actual address. If he goes there, mention that Ian with the purple Stag gave the recommendation