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How to calculate engine volume ? The engine have its original 1498cc with 90mm bore. So, when the small V4 is made for Group 2 under 1600cc class, there is lot of room to bore up. That specific engine have 92mm bore which make total engine volum like this: 3,14(pii) x (46(half of sylinder bore) x 46 (half of sylinder bore)) x 58,86 (1,5 liters V4 engine stroke) x 4 (number of sylinders) / 1000.   Simply, isnt ?

Result is ca 1564cc. So its long way under limits. 93mm bore will give ca 1599cc, which is optimal.

Plastigage is good way to check bearing clearance. I have made it allways, and newer been any problem with too tight or loose clearance. Its nice and good to know which is the clearance value, so you can better choose whether you need shorter or longer test driving period before you start really bush the engine in the forest stages. I prefer lit bit more clearance to secure that engine doesnt stuck and it will round easily RPMs up.

Plastigage is like a tiny rope made in wax. You can find it for example thru local engine machinery shop, there is different size to choose.

You just put some piece of plastigage under bearing towards Crankshaft and tight bearing cap as mentioned in Workshop manual. Saab V4 manual has good step by step instructions.

After you open the bearing cap, you can easily measure the clearance value by using plastigages own measuring scale.

Same clearance checked also from conrods. Notice new ARP conrod bolts tight with ARP own grease. Tightening step by step three times up to 40NM ( ARP value 38NM).  Nice to see, if it works (without Loctite glue). Conrod bolts are one weakpoint in V4 when rew high RPM. In this photo, notice steel balance shaft gear.

Old stuff from 70´s; original Saab rally camfollowers and NOS Saab Works Finland camsaft. I really like to see how Old School engine works against those Escort´s which are developed during 30 years much far away from which those cars were in a past.

AE 5B1. The name AE gomes from AYA-10 ex driver Aarno Erola, who has a engine machining workshop those days. There made all machining to Saab Works Rally Team Finland. More near really historic rallying it could not be, or what you think ?

Cam followers are old ones, just grinded in machining workshop to the right convex shape. These are lighter and stronger than V4 standard lifters.